Science.gov

Sample records for methylcellulose

  1. 21 CFR 172.874 - Hydroxypropyl methylcellulose.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Hydroxypropyl methylcellulose. 172.874 Section 172.874 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Multipurpose Additives § 172.874 Hydroxypropyl methylcellulose. The...

  2. 21 CFR 172.874 - Hydroxypropyl methylcellulose.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... CONSUMPTION Multipurpose Additives § 172.874 Hydroxypropyl methylcellulose. The food additive hydroxypropyl... provide for such use if: (a) The additive complies with the definition and specifications prescribed in..., protective colloid, stabilizer, suspending agent, or thickener, in accordance with good...

  3. 21 CFR 172.874 - Hydroxypropyl methylcellulose.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... CONSUMPTION Multipurpose Additives § 172.874 Hydroxypropyl methylcellulose. The food additive hydroxypropyl... provide for such use if: (a) The additive complies with the definition and specifications prescribed in..., protective colloid, stabilizer, suspending agent, or thickener, in accordance with good...

  4. 21 CFR 172.874 - Hydroxypropyl methylcellulose.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... CONSUMPTION Multipurpose Additives § 172.874 Hydroxypropyl methylcellulose. The food additive hydroxypropyl... provide for such use if: (a) The additive complies with the definition and specifications prescribed in..., protective colloid, stabilizer, suspending agent, or thickener, in accordance with good...

  5. 21 CFR 172.874 - Hydroxypropyl methylcellulose.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... CONSUMPTION Multipurpose Additives § 172.874 Hydroxypropyl methylcellulose. The food additive hydroxypropyl... provide for such use if: (a) The additive complies with the definition and specifications prescribed in..., protective colloid, stabilizer, suspending agent, or thickener, in accordance with good...

  6. LT-HSC Methylcellulose Assay

    PubMed Central

    Kerenyi, Marc A.

    2016-01-01

    Hematopoietic differentiation is a highly complex process originating from an extraordinary population of cells called long-term repopulating hematopoietic stem cells (LT-HSCs). The unique feature of all stem cells, including HSCs, is their exceptional ability to divide asymmetrically giving rise to two different kinds of offspring. One daughter cell becomes an LT-HSC itself (self-renews) to maintain the LT-HSC pool, whereas the second daughter cell pursues a differentiation fate to ultimately give rise to terminally differentiated mature blood cells (Orkin and Zon, 2008). Quantification of phenotypic LT-HSCs can be performed by multi-color flow cytometry and the gold standard for assessment of LT-HSC self-renewal and function is competitive bone marrow transplantation (Miller et al., 2008). Although these methods are irreplaceable to determine LT-HSC abundance and functionality, they have their disadvantages and limitations. For example, competitive bone marrow transplantation is typically monitored as a function of peripheral blood donor contribution over 12–16 weeks. While reduced peripheral blood donor contribution by itself signifies impairment in the stem/progenitor cells compartment, it cannot unambiguously discriminate between reduced LT-HSC self-renewal, impaired LT-HSC differentiation or compromised progenitor cell differentiation. Here we describe an LT-HSCs methylcellulose colony-forming assay, as a fast complementary in vitro method to directly assess LT-HSC differentiation capacity. As described in Kerenyi et al. (2013), this technique acts as a powerful tool to differentiate between LT-HSC or progenitor cell differentiation defects.

  7. Bacterial culture preservation in frozen and dry-film methylcellulose.

    PubMed

    Suslow, T V; Schroth, M N

    1981-11-01

    Forty-seven of 61 bacterial cultures, including strains of Pseudomonas, Xanthomonas, Erwinia, Agrobacterium, Corynebacterium, Serratia, Klebsiella, and Escherichia, remained viable after storage in frozen methylcellulose or in dried methylcellulose for up to 38 months. Pathogenicity remained intact for those strains tested. Bacteria were grown on a solid medium and then removed and placed in 1.0% methylcellulose (cellulose methyl ether) to make a final suspension of 10 colony-forming units (CFU) per ml. For storage in dried form, the bacteria-methylcellulose suspension was placed in a petri dish and dried in a forced-air incubator. After 24 h of storage at 25 degrees C, viable populations of 10 CFU/mg (equivalent to 10 CFU/ml) were recovered. Populations of 10 to 10 CFU/mg were recovered after storage of up to 38 months. Similar results were obtained in frozen methylcellulose. Survival was greatly enhanced when the growth medium for the bacteria was potato dextrose peptone rather than nutrient agar, yeast dextrose calcium carbonate peptone, or King's medium B. Addition of 0.1 M MgSO(4) to the methylcellulose suspension and to the resuspending liquid also increased survival and recovery from storage for some strains. Methylcellulose storage should be a simple, inexpensive, and reliable method of maintaining cultures for short or long periods of time. PMID:16345889

  8. Properties of Novel Hydroxypropyl Methylcellulose Films Containing Chitosan Nanoparticles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this work, chitosan nanoparticles were prepared and incorporated in hydroxypropyl methylcellulose (HPMC) films under different conditions. Mechanical properties, water vapor and oxygen permeability, water solubility and scanning and transmission electron microscopy (SEM and TEM) results were ana...

  9. Mechanism of misoprostol stabilization in hydroxypropyl methylcellulose.

    PubMed

    Kararli, T T; Catalano, T; Needham, T E; Finnegan, P M

    1991-01-01

    The stability of misoprostol oil is significantly improved in a hydroxypropyl methylcellulose (HPMC) dispersion (1:100). In order to understand the enhanced stability of misoprostol oil in HPMC, the physical state of misoprostol oil in HPMC films was investigated using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and transmission IR (TIR). Further, to determine the effect of polymer structure and the mobility of both water and misoprostol on misoprostol stability, the rate of misoprostol degradation was investigated in the misoprostol/HPMC dispersion (1:100) at 55 degrees C. The water sorption isotherm of the dispersion at 55 degrees C was determined, at seven different relative humidities, ranging from zero to 81%. The DSC and DMA measurements indicated that misoprostol oil, up to 29% in dry weight, is molecularly dispersed in the glassy HPMC. The TIR studies showed no evidence of complexation between misoprostol and HPMC. Stability studies of the misoprostol/HPMC (1:100) dispersion indicated that the first-order rate constants for misoprostol degradation increased in a concave-up fashion as the water content of the dispersion increased. Below two percent water content, the rate of misoprostol degradation was found to be minimal. Overall, it is suggested that misoprostol is stabilized in the dispersion by being molecularly dispersed in HPMC. Further, the glassy state of HPMC should reduce the mobility of misoprostol and water, leading to a minimal rate of degradation for misoprostol at low moisture levels. PMID:1746334

  10. Agarose and methylcellulose hydrogel blends for nerve regeneration applications

    NASA Astrophysics Data System (ADS)

    Martin, Benton C.; Minner, Eric J.; Wiseman, Sherri L.; Klank, Rebecca L.; Gilbert, Ryan J.

    2008-06-01

    Trauma sustained to the central nervous system is a debilitating problem for thousands of people worldwide. Neuronal regeneration within the central nervous system is hindered by several factors, making a multi-faceted approach necessary. Two factors contributing to injury are the irregular geometry of injured sites and the absence of tissue to hold potential nerve guides and drug therapies. Biocompatible hydrogels, injectable at room temperature, that rapidly solidify at physiological temperatures (37 °C) are beneficial materials that could hold nerve guidance channels in place and be loaded with therapeutic agents to aid wound healing. Our studies have shown that thermoreversible methylcellulose can be combined with agarose to create hydrogel blends that accommodate these properties. Three separate novel hydrogel blends were created by mixing methylcellulose with one of the three different agaroses. Gelation time tests show that the blends solidify at a faster rate than base methylcellulose at 37 °C. Rheological data showed that the elastic modulus of the hydrogel blends rapidly increases at 37 °C. Culturing experiments reveal that the morphology of dissociated dorsal root ganglion neurons was not altered when the hydrogels were placed onto the cells. The different blends were further assessed using dissolution tests, pore size evaluations using scanning electron microscopy and measuring the force required for injection. This research demonstrates that blends of agarose and methylcellulose solidify much more quickly than plain methylcellulose, while solidifying at physiological temperatures where agarose cannot. These hydrogel blends, which solidify at physiological temperatures naturally, do not require ultraviolet light or synthetic chemical cross linkers to facilitate solidification. Thus, these hydrogel blends have potential use in delivering therapeutics and holding scaffolding in place within the nervous system.

  11. Effects of coating rectangular microscopic electrophoresis chamber with methylcellulose

    NASA Technical Reports Server (NTRS)

    Plank, L. D.

    1985-01-01

    One of the biggest problems in obtaining high accuracy in microscopic electrophoresis is the parabolic flow of liquid in the chamber due to electroosmotic backflow during application of the electric field. In chambers with glass walls the source of polarization leading to electroosmosis is the negative charge of the silicare and other ions that form the wall structure. It was found by Hjerten, who used a rotating 3.0 mm capillary tube for free zone electrophoresis, that precisely neutralizing this charge was extremely difficult, but if a neutral polymer matrix (formaldehyde fixed methylcellulose) was formed over the glass (quartz) wall the double layer was displaced and the viscosity at the shear plane increased so that electroosmotic flow could be eliminated. Experiments were designed to determine the reliability with which methylcellulose coating of the Zeiss Cytopherometer chamber reduced electroosmotic backflow and the effect of coating on the accuracy of cell electrophoretic mobility (EPN) determinations. Fixed rat erythrocytes (RBC) were used as test particles.

  12. TiO2/methylcellulose nanocomposite films for photocatalytic applications

    NASA Astrophysics Data System (ADS)

    Rosu, M. C.; Suciu, R. C.; Dreve, S. V.; Silipas, T. D.; Bratu, I.; Indrea, E.

    2012-02-01

    TiO2/methylcellulose (MeC) nanocomposite films were obtained by wet-chemical techniques using MeC and/or additives (acetylacetone, polyethylene glycol and Triton X-100). Thin films were obtained by spin-coating the colloidal suspensions on conductive indium tin oxide (ITO) glass, followed by a heat-treatment. The effect of MeC and additives on TiO2 nanoparticles dispersion was investigated by FTIR microscopy and X-ray diffraction (for structural and morphological properties), UV-VIS absorption spectroscopy and spectrofluorimetry (for optoelectronic properties) and wet technique adhesion test (for mechanical integrity). The composite film with methylcellulose and additives has good integrity and better adhesion to ITO substrate, without losing its photocatalytic activity. The results of these experiments showed that such nanocomposite films are interesting candidate for applications in the field of photocatalytic degradation of organic pollutants.

  13. Size-exclusion chromatography of ultrahigh molecular weight methylcellulose ethers and hydroxypropyl methylcellulose ethers for reliable molecular weight distribution characterization.

    PubMed

    Li, Yongfu; Shen, Hongwei; Lyons, John W; Sammler, Robert L; Brackhagen, Meinolf; Meunier, David M

    2016-03-15

    Size-exclusion chromatography (SEC) coupled with multi-angle laser light scattering (MALLS) and differential refractive index (DRI) detectors was employed for determination of the molecular weight distributions (MWD) of methylcellulose ethers (MC) and hydroxypropyl methylcellulose ethers (HPMC) having weight-average molecular weights (Mw) ranging from 20 to more than 1,000kg/mol. In comparison to previous work involving right-angle light scattering (RALS) and a viscometer for MWD characterization of MC and HPMC, MALLS yields more reliable molecular weight for materials having weight-average molecular weights (Mw) exceeding about 300kg/mol. A non-ideal SEC separation was observed for cellulose ethers with Mw>800kg/mol, and was manifested by upward divergence of logM vs. elution volume (EV) at larger elution volume at typical SEC flow rate such as 1.0mL/min. As such, the number-average molecular weight (Mn) determined for the sample was erroneously large and polydispersity (Mw/Mn) was erroneously small. This non-ideality resulting in the late elution of high molecular weight chains could be due to the elongation of polymer chains when experimental conditions yield Deborah numbers (De) exceeding 0.5. Non-idealities were eliminated when sufficiently low flow rates were used. Thus, using carefully selected experimental conditions, SEC coupled with MALLS and DRI can provide reliable MWD characterization of MC and HPMC covering the entire ranges of compositions and molecular weights of commercial interest. PMID:26794765

  14. Properties of novel hydroxypropyl methylcellulose films containing chitosan nanoparticles.

    PubMed

    de Moura, M R; Avena-Bustillos, R J; McHugh, T H; Krochta, J M; Mattoso, L H C

    2008-09-01

    In this study, chitosan nanoparticles were prepared and incorporated in hydroxypropyl methylcellulose (HPMC) films under different conditions. Mechanical properties, water vapor and oxygen permeability, water solubility, and scanning and transmission electron microscopy (SEM and TEM) results were analyzed. Incorporation of chitosan nanoparticles in the films improved their mechanical properties significantly, while also improving film barrier properties significantly. The chitosan poly(methacrylic acid) (CS-PMAA) nanoparticles tend to occupy the empty spaces in the pores of the HPMC matrix, inducing the collapse of the pores and thereby improving film tensile and barrier properties. This study is the first to investigate the use of nanoparticles for the purpose of strengthening HPMC films. PMID:18803724

  15. Radiation effects on hydroxypropyl methylcellulose phthalate in aqueous system

    NASA Astrophysics Data System (ADS)

    Xu, Ling; Yue, Zhiying; Wang, Min; Zhai, Maolin; Yoshii, Fumio; Seko, Noriaki; Peng, Jing; Wei, Genshuan; Li, Jiuqiang

    2007-12-01

    A water-insoluble cellulose derivative, hydroxypropyl methylcellulose phthalate (HPMCP) hydrogels, was converted to Na type to form hydrogel in paste-like status by radiation crosslinking. Mechanism for radiation crosslinking of cellulose-derivatives in paste-like status was discussed. Crosslinkers, i.e. methyl N, N-bis-acrylamide (MBA) or ethyleneglycol dimethacrylate (EGDMA) has been used to decrease gelation dose (Dg) of synthesis HPMCP hydrogels and improve its mechanical properties. HPMCP-MBA hydrogels were found to be more rigid and HPMCP-EGDMA hydrogels were more flexible. Swelling degree of HPMCP hydrogel in many kinds of salt solutions followed Hofmeister series, which is ubiquitous in polyelectrolyte hydrogel. Specific reswelling was observed in concentrated KF solution, implying a very strong F - binding ability of benzyl group. The comprehensive results obtained in this study will be utilized on the design of HPMCP-based controlled release system.

  16. Dietary hydroxypropyl methylcellulose increases excretion of saturated and trans fats by hamsters fed fast food diets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The hypocholesterolemic and hypoglycemic effects of hydroxypropyl methylcellulose (HPMC), a semisynthetic nonfermentable soluble dietary fiber, are well established. However, effects of HPMC on dietary saturated fatty acids and trans fatty acids are largely unknown. This study investigated the eff...

  17. The characterization of hydroxypropyl methylcellulose through the analysis of its substituents

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The methyl and hydroxypropyl substituents in hydroxypropyl methylcellulose (HPMC) affect the resulting gel properties. These substituents in five HPMC gels were characterized using Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, small-amplitude oscillatory shear measurements, a...

  18. Improved barrier and mechanical properties of novel hydroxypropyl methylcellulose edible films with chitosan/tripolyphosphate nanoparticles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chitosan/tripolyphosphate nanoparticles were prepared and incorporated in hydroxypropyl methylcellulose (HPMC) films. FT-IR and transmission electron microscopy (TEM) analyses of the nanoparticles, mechanical properties, water vapor permeability, thermal stability, scanning electron microscopy (SEM...

  19. Structure and phase behavior of aqueous methylcellulose solutions

    NASA Astrophysics Data System (ADS)

    McAllister, John; Schmidt, Peter; Lodge, Timothy; Bates, Frank

    2015-03-01

    Cellulose ethers (CE) constitute a multi-billion dollar industry, and have found end uses in a broad array of applications from construction materials, food products, personal care products, and pharmaceuticals for more than 80 years. Methylcellulose (MC, with the trade name METHOCEL™) is a CE in which there is a partial substitution of -OH groups with -OCH3 groups. This results in a polymer that is water-soluble at low temperatures, and aqueous solutions of MC display gelation and phase separation at higher temperatures. The nature of MC gelation has been debated for many years, and this project has made significant advances in the understanding of the solution properties of CEs. We have characterized a fibrillar structure of MC gels by cryogenic transmission electron microscopy (cryo-TEM) and small angle neutron scattering (SANS). Using light scattering, turbidity measurements, and dynamic mechanical spectroscopy (DMS) we report that MC microphase separates by nucleation and growth of fibril aggregates, and is a different process from LCST phase separation.

  20. Thermally responsive wettability of self-assembled methylcellulose nanolayers

    NASA Astrophysics Data System (ADS)

    Yokota, Shingo; Matsuyama, Kana; Kitaoka, Takuya; Wariishi, Hiroyuki

    2007-03-01

    Thermo-responsive cellulosic nanolayers were prepared from methylcellulose (MC), which is known to have a unique lower critical solution temperature. Thiosemicarbazide (TSC) was selectively introduced into the MC reducing end groups, and the corresponding MC-TSC derivative was spontaneously chemisorbed on an Au substrate at 4 °C to give MC self-assembled monolayers (SAMs). Linear MC chains were stably fixed onto the Au substrate, yielding an MC-SAM of thickness ca. 15 nm with a root mean square value less than 1 nm. The MC-SAM surface exhibited thermally responsive wetting characteristics; the water contact angle was found to rise and fall around 70 °C, possibly due to the solid-state phase transition of the MC nanolayers resulting from the inherent gelation of MC molecules in water. Such wetting behavior was shown to be reversible following repeated heating and cooling. The MC-SAM immersed in salt solution revealed lower phase transition temperatures, and an increase in sodium chloride concentration ranging from 0.0 to 1.0 M brought about a dramatic decrease in the apparent phase transition temperature from ca. 70 to 30 °C. For the purposely designed MC nanolayers, such controllable wetting properties are expected to prompt growing interest in the applications of cellulosic biopolymer interfaces.

  1. Characterization of paraffin oil emulsions stabilized by hydroxypropyl methylcellulose.

    PubMed

    Futamura, Taiki; Kawaguchi, Masami

    2012-02-01

    To study the relationship between emulsion stability and polymer emulsifier concentration, the preparation of paraffin oil emulsions by hydroxypropyl methylcellulose (HPMC) was carried out with HPMC concentrations below the overlapping concentration (C(*)) of HPMC. The stability of the emulsions incorporating HPMC was investigated by measuring the creaming velocity, volume fraction of emulsified paraffin oil, oil droplet size, and some rheological responses such as the stress-strain sweep curve and strain and frequency dependences of dynamic viscoelastic moduli. The paraffin oil was almost emulsified by HPMC above C(*)/20: the volume fraction of paraffin oil in the emulsion was higher than 0.72. Increasing in the HPMC concentration led to decreases in both the average oil droplet size and creaming velocity and an increase in the yield stress. All emulsions behaved as solid-like viscoelastic matter. Additionally, the measured dynamic storage moduli were compared with those calculated from a relationship based on functions of the volume fraction of oil in the emulsions and Laplace pressure; good agreement between the measured and calculated moduli was obtained. On the other hand, at HPMC concentrations below C(*)/50, the emulsified paraffin oil became unstable and the oil and the HPMC solution eventually separated. PMID:22138268

  2. Development of photocrosslinked methylcellulose hydrogels for soft tissue reconstruction.

    PubMed

    Stalling, Simone S; Akintoye, Sunday O; Nicoll, Steven B

    2009-07-01

    A variety of materials have been used as fillers for soft tissue augmentation. In this study, methylcellulose (MC), a water-soluble derivative of the polysaccharide cellulose, was modified with functional methacrylate groups and photocrosslinked to produce hydrogels for potential application in plastic and reconstructive surgery. Purified macromer (5% theoretical modification, 2.3% actual) was resuspended in 0.05wt.% of the photoinitiator, 2-methyl-1-[4-(hydroxyethoxy)phenyl]-2-methyl-1-propanone, cast into custom molds, and exposed to long-wavelength UV light for 10min to form gels. Photocrosslinked MC hydrogels at varying weight/volume percentages displayed equilibrium weight swelling ratios (wet weight/dry weight) and elastic moduli of 30+/-3 to 17+/-2 and 8.48+/-0.25kPa to 23.21+/-1.55kPa, respectively, demonstrating the formation of stable gels with tunable properties. Human dermal fibroblasts grown in the presence of MC hydrogels in vitro exhibited no significant changes in cell viability after 5days of co-culture, indicating that the materials are non-cytotoxic. Higher weight percentage MC hydrogels (6%) implanted subcutaneously in CD-1 mice maintained their integrity and original dimensions after 80days in vivo, eliciting a mild inflammatory response with no observed inflammatory exudate, minimal vascular infiltration and thin translucent fibrous capsule formation of approximately 50microm in thickness. Taken together, the material and biological properties of photocrosslinked MC hydrogels suggest that they may be of use in soft tissue reconstruction. PMID:19303378

  3. Stability of methylcellulose-based films after being subjected to different conservation and processing temperatures.

    PubMed

    Tavera Quiroz, M J; Lecot, J; Bertola, N; Pinotti, A

    2013-07-01

    Methylcellulose films with and without sorbitol addition were developed. The major objective of this study was to attempt insights into the stability of the methylcellulose-based film properties after having been subjected to freezing, storage or a combination of both procedures. The importance of the sorbitol concentration and process temperature was also to be elucidated. As-prepared film solubility decreased at 100 °C, as a result of the methylcellulose thermogelation property when the samples were exposed to high temperatures. By analyzing the film pattern behavior and its properties 0.25% w/v sorbitol concentration turned out to be an inflexion point. The moisture content as well as the mechanical and thermal properties made this fact evident. Moreover the elastic modulus (Ec) and glass transition temperature (Tg) did not undergo significant changes for higher plasticizer concentrations. The methylcellulose film properties remained more stable in the presence of sorbitol, which would act as a protective agent due to its hydrogen bonding capacity. This stability is crucial for film and coating applications in the food industry. PMID:23623115

  4. Solution blow spun Poly(lactic acid)/Hydroxypropyl methylcellulose nanofibers with antimicrobial properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Poly(lactic acid) (PLA) nanofibers containing hydroxypropyl methylcellulose (HPMC) and tetracycline hydrochloride (THC) were solution blow spun from two different solvents, chloroform/acetone (CA, 80:20 v/v) and 2,2,2-triflouroethanol (TFE). The diameter distribution, chemical, thermal, thermal stab...

  5. Hybrid Crosslinked Methylcellulose Hydrogel: A Predictable and Tunable Platform for Local Drug Delivery.

    PubMed

    Pakulska, Malgosia M; Vulic, Katarina; Tam, Roger Y; Shoichet, Molly S

    2015-09-01

    Design of experiment is used to develop a hybrid methylcellulose hydrogel that combines physical and chemical crosslinks, resulting in an injectable, in situ stiffening, and long-lasting material with predictable swelling and rheological properties. Chemical crosslinking is complete prior to injection, allowing for ease of use and storage. Controlled release of two relevant protein therapeutics and biocompatibility of the hydrogel are demonstrated. PMID:26184559

  6. Nanoparticle suspensions enclosed in methylcellulose: a new approach for quantifying nanoparticles in transmission electron microscopy

    PubMed Central

    Hacker, Christian; Asadi, Jalal; Pliotas, Christos; Ferguson, Sophie; Sherry, Lee; Marius, Phedra; Tello, Javier; Jackson, David; Naismith, James; Lucocq, John Milton

    2016-01-01

    Nanoparticles are of increasing importance in biomedicine but quantification is problematic because current methods depend on indirect measurements at low resolution. Here we describe a new high-resolution method for measuring and quantifying nanoparticles in suspension. It involves premixing nanoparticles in a hydrophilic support medium (methylcellulose) before introducing heavy metal stains for visualization in small air-dried droplets by transmission electron microscopy (TEM). The use of methylcellulose avoids artifacts of conventional negative stain-TEM by (1) restricting interactions between the nanoparticles, (2) inhibiting binding to the specimen support films and (3) reducing compression after drying. Methylcellulose embedment provides effective electron imaging of liposomes, nanodiscs and viruses as well as comprehensive visualization of nanoparticle populations in droplets of known size. These qualities facilitate unbiased sampling, rapid size measurement and estimation of nanoparticle numbers by means of ratio counting using a colloidal gold calibrant. Specimen preparation and quantification take minutes and require a few microliters of sample using only basic laboratory equipment and a standard TEM. PMID:27141843

  7. Nanoparticle suspensions enclosed in methylcellulose: a new approach for quantifying nanoparticles in transmission electron microscopy.

    PubMed

    Hacker, Christian; Asadi, Jalal; Pliotas, Christos; Ferguson, Sophie; Sherry, Lee; Marius, Phedra; Tello, Javier; Jackson, David; Naismith, James; Lucocq, John Milton

    2016-01-01

    Nanoparticles are of increasing importance in biomedicine but quantification is problematic because current methods depend on indirect measurements at low resolution. Here we describe a new high-resolution method for measuring and quantifying nanoparticles in suspension. It involves premixing nanoparticles in a hydrophilic support medium (methylcellulose) before introducing heavy metal stains for visualization in small air-dried droplets by transmission electron microscopy (TEM). The use of methylcellulose avoids artifacts of conventional negative stain-TEM by (1) restricting interactions between the nanoparticles, (2) inhibiting binding to the specimen support films and (3) reducing compression after drying. Methylcellulose embedment provides effective electron imaging of liposomes, nanodiscs and viruses as well as comprehensive visualization of nanoparticle populations in droplets of known size. These qualities facilitate unbiased sampling, rapid size measurement and estimation of nanoparticle numbers by means of ratio counting using a colloidal gold calibrant. Specimen preparation and quantification take minutes and require a few microliters of sample using only basic laboratory equipment and a standard TEM. PMID:27141843

  8. Organic/inorganic hybrid synaptic transistors gated by proton conducting methylcellulose films

    NASA Astrophysics Data System (ADS)

    Wan, Chang Jin; Zhu, Li Qiang; Wan, Xiang; Shi, Yi; Wan, Qing

    2016-01-01

    The idea of building a brain-inspired cognitive system has been around for several decades. Recently, electric-double-layer transistors gated by ion conducting electrolytes were reported as the promising candidates for synaptic electronics and neuromorphic system. In this letter, indium-zinc-oxide transistors gated by proton conducting methylcellulose electrolyte films were experimentally demonstrated with synaptic plasticity including paired-pulse facilitation and spatiotemporal-correlated dynamic logic. More importantly, a model based on proton-related electric-double-layer modulation and stretched-exponential decay function was proposed, and the theoretical results are in good agreement with the experimentally measured synaptic behaviors.

  9. Preparation and characterization of SiO2/TiO2/methylcellulose hybrid thick films for optical waveguides

    NASA Astrophysics Data System (ADS)

    Yang, Jun; Zhang, Xinyu; Wang, Pei; Ming, Hai; Wu, Yunxia; Xie, Jianping; Zhang, Junying

    2005-07-01

    SiO2/TiO2/methylcellulose composite materials processed by the sol-gel technique were studied for optical waveguide applications. With the help of methylcellulose, an organic binder, SiO2/TiO2/methylcellulose hybrid thick films were prepared by a single spin-coating processes. After annealing at 70 Celsius degree for an hour, 2.5-?m crack-free and dense organic--inorganic hybrid optical films with a refractive index of 1.537 were achieved. Optical losses of plane waveguide made up of those films and ordinary slide glass substrate are around 0.3 dB/cm at 650 nm. Scanning electronmicroscopy (SEM) and UV-visible spectroscopy (UV-VIS), have been used to characterize the thick films.

  10. A Coarse Grained Model for Methylcellulose: Spontaneous Ring Formation at Elevated Temperature

    NASA Astrophysics Data System (ADS)

    Huang, Wenjun; Larson, Ronald

    Methylcellulose (MC) is widely used as food additives and pharma applications, where its thermo-reversible gelation behavior plays an important role. To date the gelation mechanism is not well understood, and therefore attracts great research interest. In this study, we adopted coarse-grained (CG) molecular dynamics simulations to model the MC chains, including the homopolymers and random copolymers that models commercial METHOCEL A, in an implicit water environment, where each MC monomer modeled with a single bead. The simulations are carried using a LAMMPS program. We parameterized our CG model using the radial distribution functions from atomistic simulations of short MC oligomers, extrapolating the results to long chains. We used dissociation free energy to validate our CG model against the atomistic model. The CG model captured the effects of monomer substitution type and temperature from the atomistic simulations. We applied this CG model to simulate single chains up to 1000 monomers long and obtained persistence lengths that are close to those determined from experiment. We observed the chain collapse transition for random copolymer at 600 monomers long at 50C. The chain collapsed into a stable ring structure with outer diameter around 14nm, which appears to be a precursor to the fibril structure observed in the methylcellulose gel observed by Lodge et al. in the recent studies. Our CG model can be extended to other MC derivatives for studying the interaction between these polymers and small molecules, such as hydrophobic drugs.

  11. Miniaturization of cellulose fibers and effect of addition on the mechanical and barrier properties of hydroxypropyl methylcellulose

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cellulose fibers were miniaturized by microfluidics technology and incorporated in hydroxypropyl methylcellulose (HPMC) films to study the effect of the addition of such fibers on the mechanical and barrier properties of HPMC films suitable for food packaging applications. The particle size of the f...

  12. Hypocholesterolemic effects of hydroxypropyl methylcellulose are mediated by altered gene expression in hepatic bile and cholesterol pathways of male hamsters

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hydroxypropyl methylcellulose (HPMC), a semi-synthetic non-fermentable soluble dietary fiber (SDF) modulates plasma lipoprotein profiles and hepatic lipid levels. HPMC is not absorbed by the body but its presence in the intestinal lumen increases fecal fat, sterol, and bile acid excretion and decrea...

  13. Histology of a novel injectable filler (polymethylmethacrylate and cross-linked dextran in hydroxypropyl methylcellulose) in a rat model.

    PubMed

    Lee, Young Bok; Park, Sae Mi; Song, Eun Jong; Park, Jun-Gyu; Cho, Kyoung-Oh; Kim, Jin Wou; Yu, Dong Soo

    2014-08-01

    A novel injectable filler of polymethylmethacrylate (PMMA) and cross-linked dextran in hydroxypropyl methylcellulose was introduced in the commercial filler market. For soft tissue augmentation, safety and biocompatibility should be evaluated and the stability at the implantation site should be assessed using histologic evaluation. In order to evaluate the biocompatibility of the novel soft tissue filler, PMMA and cross-linked dextran in hydroxypropyl methylcellulose was subdermally injected into the skin of Sprague-Dawley Rats. Histologic evaluation was performed at 13 weeks and 12 months after the injection. Inflammatory cell infiltration, neovascularization, and fibrosis were scored according to defined grading systems. The mean score of the histologic evaluation was 5.7 and 3.9 at 13 weeks and 12 months, respectively. At 12 months after injection, the PMMA and cross-linked dextran in hydroxypropyl methylcellulose appeared to be kept in place through fine fibrous capsules. The mixture of PMMA and cross-linked dextran in hydroxypropyl methylcellulose can be safely applied for soft tissue augmentation with longevity of greater than 12 months. PMID:24684519

  14. Development of crosslinked methylcellulose hydrogels for soft tissue augmentation using an ammonium persulfate-ascorbic acid redox system.

    PubMed

    Gold, Gittel T; Varma, Devika M; Taub, Peter J; Nicoll, Steven B

    2015-12-10

    Hydrogels composed of methylcellulose are candidate materials for soft tissue reconstruction. Although photocrosslinked methylcellulose hydrogels have shown promise for such applications, gels crosslinked using reduction-oxidation (redox) initiators may be more clinically viable. In this study, methylcellulose modified with functional methacrylate groups was polymerized using an ammonium persulfate (APS)-ascorbic acid (AA) redox initiation system to produce injectable hydrogels with tunable properties. By varying macromer concentration from 2% to 4% (w/v), the equilibrium moduli of the hydrogels ranged from 1.47 ± 0.33 to 5.31 ± 0.71 kPa, on par with human adipose tissue. Gelation time was found to conform to the ISO standard for injectable materials. Cellulase treatment resulted in complete degradation of the hydrogels within 24h, providing a reversible corrective feature. Co-culture with human dermal fibroblasts confirmed the cytocompatibility of the gels based on DNA measurements and Live/Dead imaging. Taken together, this evidence indicates that APS-AA redox-polymerized methylcellulose hydrogels possess properties beneficial for use as soft tissue fillers. PMID:26428151

  15. Removal of paraquat pesticide from aqueous solutions using a novel adsorbent material based on polyacrylamide and methylcellulose hydrogels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This research studied the characteristics of poly(acrylamide) and methylcellulose (PAAm-MC) hydrogels as a novel adsorbent material for removal of pesticide paraquat, from aqueous solution, with potential applications in curbing environmental risk from such herbicides. PAAm-MC hydrogels with differe...

  16. Characterization of antioxidant methylcellulose film incorporated with α-tocopherol nanocapsules.

    PubMed

    Noronha, Carolina Montanheiro; de Carvalho, Sabrina Matos; Lino, Renata Calegari; Barreto, Pedro Luiz Manique

    2014-09-15

    Biodegradable and antioxidant films based on methylcellulose (MC) and α-tocopherol nanocapsule suspension (NCs) were developed. MC and NCs films were prepared by a casting method in three different proportions. The mechanical, wettability, colour, light transmission, antioxidant and release characteristics of the films were studied. The addition of NCs to MC films decreased the tensile strength (TS) and the elastic modulus (EM) (p<0.05) but increased the percentage elongation at break (%E) and thickness (p<0.05). NCs films showed a higher hydrophobicity when compared to that of film control. Lightness and yellowish color were intensified in the NCs films which, in their turn, demonstrated high antioxidant activity and excellent barrier properties against UV and visible light. A burst and prolonged release of α-tocopherol to food simulant was also reported. PMID:24767092

  17. Interaction between hydroxypropyl methylcellulose and biphasic calcium phosphate after steam sterilisation: capillary gas chromatography studies.

    PubMed

    Bourges, X; Schmitt, M; Amouriq, Y; Daculsi, G; Legeay, G; Weiss, P

    2001-01-01

    The purpose of this study was to check the chemical stability of an injectable bone substitute (IBS) composed of a 50/50 w/w mixture of 2.92% hydroxypropyl methylcellulose (HPMC) solution in deionized water containing biphasic calcium phosphate (BCP) granules (60% hydroxyapatite/40% beta-tricalcium phosphate w/w). After separation of the organic and mineral phases, capillary gas chromatography (GC) was used to study the possible modification of HPMC due to the contact with BCP granules following steam sterilisation and 32 days storage at room temperature. HPMC was extracted from IBS in aqueous medium, and a dialytic method was then used to extract calcium phosphate salts from the HPMC. The percentage of HPMC extracted from BCP was 98.5%+/-0.5%, as measured by UV. GC showed no chemical modifications after steam sterilisation and storage. PMID:11556737

  18. Interaction between hydroxypropyl methylcellulose and biphasic calcium phosphate after steam sterilisation: capillary gas chromatography studies

    PubMed Central

    Bourges, Xavier; Schmitt, Michel; Amouriq, Yves; Daculsi, Guy; Legeay, Gilbert; Weiss, Pierre

    2001-01-01

    The purpose of this study was to check the chemical stability of an injectable bone substitute (IBS) composed of a 50/50 w/w mixture of a 2.92% hydroxypropyl methylcellulose (HPMC) solution in deionised water containing biphasic calcium phosphate (BCP) granules (60% hydroxyapatite/40% β-tricalcium phosphate w/w). After separation of the organic and mineral phases, capillary gas chromatography (GC) was used to study the possible modification of HPMC due to the contact with BCP granules following steam sterilisation and 32 days of storage at room temperature. HPMC was extracted from IBS in aqueous medium, and a dialytic method was then use to extract calcium phosphate salts from HPMC. The percentage of HPMC extracted from BCP was 98.5% ± 0.5% as measured by a UV method. GC showed no chemical modifications after steam sterilisation and storage. PMID:11556737

  19. Relationship between morphologies and mechanical properties of hydroxypropyl methylcellulose/hydroxypropyl starch blends.

    PubMed

    Wang, Yanfei; Zhang, Liang; Liu, Hongsheng; Yu, Long; Simon, George P; Zhang, Nuozi; Chen, Ling

    2016-11-20

    Edible films from the blending hydroxypropyl methylcellulose (HPMC) with hydroxypropyl starch (HPS) have been developed. This work focuses on the relationship between morphologies and mechanical properties of such systems. To aid understanding of blend morphology, a new technique used to identify the two phases through dying of the HPS by iodine has been developed, which provided a simple and convenient way to clearly distinguish between HPMC and HPS phases. It was found that the blend system is immiscible and there is phase transition point depending on blending ratio and solution concentration. The lower transparency point of the blend and phase transition reign of HPMC from continuous phase to separated phase correspond with the variation of tensile modulus. The modulus and elongation decreased with increased solution concentration, which is correlatable with the morphologies present, where it was found that the HPMC gradually changed from a continuous phase to a distinct phase. PMID:27561503

  20. The shear dependence of the methylcellulose gelation phenomena in aqueous solution and in ceramic paste.

    PubMed

    Knarr, Matthias; Bayer, Roland

    2014-10-13

    The gelation temperature of methylcellulose (MC) in aqueous solutions as well as in aqueous ceramic paste depends on the applied shear. Rheological investigations in oscillation vs. shear mode show lower gelation temperature at low shear rates as for the corresponding angular frequencies. Above a critical shear rate the gelation temperature is shifted to higher temperatures. The paste extrusion process uses MC as a plasticizer and runs under high shear conditions. When extruding close to the gelation temperature of the MC in the paste, crack formation and other defects can occur. The upwards shift of the gelation temperature with increasing applied shear gives a larger temperature window during the extrusion process. The understanding of the shear influence on the gelation temperature is important to design the optimal process conditions. PMID:25037332

  1. Effects of Methylcellulose on Cellulolytic Bacteria Attachment and Rice Straw Degradation in the In vitro Rumen Fermentation

    PubMed Central

    Sung, Ha Guyn; Kim, Min Ji; Upadhaya, Santi Devi; Ha, Jong K.; Lee, Sung Sill

    2013-01-01

    An in vitro experiment was conducted to evaluate the effect of methylcellulose on the attachment of major cellulolytic bacteria on rice straw and its digestibility. Rice straw was incubated with ruminal mixture with or without 0.1% methylcellulose (MC). The attachment of F. succinogenes, R. flavefaciens and R. albus populations on rice straw was measured using real-time PCR with specific primer sets. Methylcellulose at the level of 0.1% decreased the attachment of all three major cellulolytic bacteria. In particular, MC treatment reduced (p<0.05) attachment of F. succinogenes on rice straw after 10 min of incubation while a significant reduction (p<0.05) in attachment was not observed until 4 h incubation in the case of R. flavefaciens and R. albus. This result indicated F. succinogenes responded to MC more sensitively and earlier than R. flavefaciens and R. albus. Dry matter digestibility of rice straw was subsequently inhibited by 0.1% MC, and there was a significant difference between control and MC treatment (p<0.05). Incubated cultures containing MC had higher pH and lower gas production than controls. Current data clearly indicated that the attachment of F. succinogenes, R. flavefaciens and R. albus on rice straw was inhibited by MC, which apparently reduced rice straw digestion. PMID:25049909

  2. Studies on methylcellulose/pectin/montmorillonite nanocomposite films and their application possibilities.

    PubMed

    Saha, Nayan Ranjan; Sarkar, Gunjan; Roy, Indranil; Rana, Dipak; Bhattacharyya, Amartya; Adhikari, Arpita; Mukhopadhyay, Asis; Chattopadhyay, Dipankar

    2016-01-20

    Films based on methylcellulose (MC) and pectin (PEC) of different ratios were prepared. MC/PEC (90:10) (MP10) gave the best results in terms of mechanical properties. Sodium montmorillonite (MMT) (1, 3 and 5 wt%) was incorporated in the MP10 matrix. The resulting films were characterized by X-ray diffraction and transmission electron microscopy, and it was found that nanocomposites were intercalated in nature. Mechanical studies established that addition of 3 wt% MMT gave best results in terms of mechanical properties. However, thermo-gravimetric and dynamic mechanical analysis proved that decomposition and glass transition temperature increased with increasing MMT concentration from 1 to 5 wt%. It was also observed that moisture absorption and water vapor permeability studies gave best result in the case of 3 wt% MMT. Optical clarity of the nanocomposite films was not much affected with loading of MMT. In vitro drug release studies showed that MC/PEC/MMT based films can be used for controlled transdermal drug delivery applications. PMID:26572465

  3. Antimicrobial and Antioxidant Activity of Chitosan/Hydroxypropyl Methylcellulose Film-Forming Hydrosols Hydrolyzed by Cellulase.

    PubMed

    Zimoch-Korzycka, Anna; Bobak, Łukasz; Jarmoluk, Andrzej

    2016-01-01

    The aim of this study was to evaluate the impact of cellulase (C) on the biological activity of chitosan/hydroxypropyl methylcellulose (CH/HPMC) film-forming hydrosols. The hydrolytic activity of cellulase in two concentrations (0.05% and 0.1%) was verified by determination of the progress of polysaccharide hydrolysis, based on viscosity measurement and reducing sugar-ends assay. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging effect, the ferric reducing antioxidant power (FRAP), and microbial reduction of Pseudomonas fluorescens, Yersinia enterocolitica, Bacillus cereus, and Staphylococcus aureus were studied. During the first 3 h of reaction, relative reducing sugar concentration increased progressively, and viscosity decreased rapidly. With increasing amount of enzyme from 0.05% to 0.1%, the reducing sugar concentration increased, and the viscosity decreased significantly. The scavenging effect of film-forming solutions was improved from 7.6% at time 0 and without enzyme to 52.1% for 0.1% cellulase after 20 h of reaction. A significant effect of cellulase addition and reaction time on antioxidant power of the tested film-forming solutions was also reported. Film-forming hydrosols with cellulase exhibited a bacteriostatic effect on all tested bacteria, causing a total reduction. PMID:27608008

  4. Gelatin/hydroxypropyl methylcellulose matrices - Polymer interactions approach for oral disintegrating films.

    PubMed

    Tedesco, Marcela P; Monaco-Lourenço, Carla A; Carvalho, Rosemary A

    2016-12-01

    Oral disintegrating film represents an optimal alternative for delivery system of active compounds. The choice of film-forming polymer is the first step in the development of oral disintegrating films and the knowledge of molecular interactions in this matrix is fundamental to advance in this area. Therefore, this study aimed to characterize gelatin and hydroxypropyl methylcellulose (HPMC) films and their blends as matrices of oral disintegrating films. The films were produced by casting technique and were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, mechanical properties, contact angle, time disintegration and bioadhesive strength. Differential scanning calorimetry showed that enthalpy of fusion and melting temperatures of the blends films were lower than those of the gelatin film, which may be associated with the lack of intra-chain interactions also observed in the Fourier transform infrared spectra. In blends, a less compact cross-section structure was observed in scanning electron microscopy images compared with isolated polymer films. The addition of HPMC increased the elongation, hydrophilicity and in vitro bioadhesive force and decreased in vitro disintegration time, important properties in the development of oral disintegrating films. Although the mixture of the polymers showed no synergistic behavior, this study may contribute to the development of new applications for polymeric matrices in the pharmaceutical industry. PMID:27612760

  5. Influence of hydroxypropyl methylcellulose edible coating on fresh-keeping and storability of tomato.

    PubMed

    Zhuang, Rong-yu; Huang, Yao-wen

    2003-01-01

    The effect of application of cellulose-based edible coating, hydroxypropyl methylcellulose (HPMC) to mature-green tomatoes on the firmness and color was investigated. Tomatoes were stored at 20 degrees C for up to 18 days. Firmness decreased as storage time increased in all treatments. However, application of HPMC edible coating delayed softening of tomatoes during 18 days of storage at 20 degrees C. At days 7, 13 and 18, the firmness of tomatoes coated with HPMC was significantly (P < or = 0.05) greater than the firmness of uncoated tomatoes. The study also confirmed that HPMC coatings could significantly (P < or = 0.05) delay the changes in color of tomatoes stored at 20 degrees C. The ripening of tomatoes from the pink stage to the red stage was successfully retarded. HPMC coating could extend the shelf life of fresh tomatoes. The retardation of the rate of loss of firmness could reduce the economic loss that would result from spoilage by mechanical injury during transportation of tomatoes. PMID:12656352

  6. Characterization of trilayer antimicrobial diffusion films (ADFs) based on methylcellulose-polycaprolactone composites.

    PubMed

    Boumail, Afia; Salmieri, Stephane; Klimas, Emilie; Tawema, Pamphile O; Bouchard, Jean; Lacroix, Monique

    2013-01-30

    Novel trilayer antimicrobial diffusion films (ADFs) were developed for food applications. ADFs were composed of two external layers of polycaprolactone and one internal layer of nanocrystalline cellulose (NCC)-reinforced methylcellulose (MC) matrix. Two antimicrobial mixtures (formulations A and B) were incorporated in the MC layer and compared via the evaluation of film properties. Resulting ADFs were inserted as diffusion devices into vegetable packages, and samples were stored at 4 °C for 14 days. Microbiological diffusion assays in the presence of ADFs were performed on pathogenic bacteria. From this, the study focused on characterizing the structural, physicochemical properties and total phenols (TP) release from ADFs. This TP release was determined by Folin-Ciocalteu's method and by FTIR analysis. Results indicated a controlled release of antimicrobials into the headspace (16.5% for formulation A and 13.4% for formulation B). Good correlations (≥90%) between both methods allowed validating an innovative, accurate, rapid FTIR procedure to quantify the diffusion of TP. SEM micrographs showed fibrillar structure due to NCC and a more compact network due to antimicrobials. Encapsulated antimicrobial formulations induced color changes without affecting visual attributes of films. ADFs containing formulation B exhibited the highest tensile strength (17.3 MPa) over storage. PMID:23286547

  7. Synergistic effect of salt mixture on the gelation temperature and morphology of methylcellulose hydrogel.

    PubMed

    Bain, Mrinal Kanti; Bhowmick, Biplab; Maity, Dipanwita; Mondal, Dibyendu; Mollick, Md Masud Rahaman; Rana, Dipak; Chattopadhyay, Dipankar

    2012-12-01

    Gelation temperature of methylcellulose (MC) can be altered by adding different additives. Pure MC showed sol-gel transition at 60°C. Sodium citrate and sodium tartrate were used alone and in combination to see the effect of individual salt and combination of salts on the gelation temperature of MC. The gelation temperature of all the binary and ternary combinations of MC and salts were measured with different methods such as test tube tilting method (TTM), UV-vis spectroscopy, viscometry, and by rheometer and also the morphology of gels were characterized with the help of environmental scanning electron microscopy (ESEM). It was observed that when 0.1 M sodium citrate (NaC) and 0.1 M sodium tartrate (NaT) were used separately, the gelation temperature of MC was reduced up to 44°C and 47°C respectively but when mixture of NaC and NaT (0.1 (M) NaC and 0.1 (M) (NaT)) were used the gelation temperature was further reduced to 36°C. It was clear from ESEM images that when NaC and NaT were used separately the formation of network was not distinguishable. But, well-connected network structure was observed when a mixture 0.1 M NaC and 0.1 M NaT was used. PMID:22884434

  8. 3D patterned stem cell differentiation using thermo-responsive methylcellulose hydrogel molds

    NASA Astrophysics Data System (ADS)

    Lee, Wonjae; Park, Jon

    2016-07-01

    Tissue-specific patterned stem cell differentiation serves as the basis for the development, remodeling, and regeneration of the multicellular structure of the native tissues. We herein proposed a cytocompatible 3D casting process to recapitulate this patterned stem cell differentiation for reconstructing multicellular tissues in vitro. We first reconstituted the 2D culture conditions for stem cell fate control within 3D hydrogel by incorporating the sets of the diffusible signal molecules delivered through drug-releasing microparticles. Then, utilizing thermo-responsivity of methylcellulose (MC), we developed a cytocompatible casting process to mold these hydrogels into specific 3D configurations, generating the targeted spatial gradients of diffusible signal molecules. The liquid phase of the MC solution was viscous enough to adopt the shapes of 3D impression patterns, while the gelated MC served as a reliable mold for patterning the hydrogel prepolymers. When these patterned hydrogels were integrated together, the stem cells in each hydrogel distinctly differentiated toward individually defined fates, resulting in the formation of the multicellular tissue structure bearing the very structural integrity and characteristics as seen in vascularized bones and osteochondral tissues.

  9. 3D patterned stem cell differentiation using thermo-responsive methylcellulose hydrogel molds.

    PubMed

    Lee, Wonjae; Park, Jon

    2016-01-01

    Tissue-specific patterned stem cell differentiation serves as the basis for the development, remodeling, and regeneration of the multicellular structure of the native tissues. We herein proposed a cytocompatible 3D casting process to recapitulate this patterned stem cell differentiation for reconstructing multicellular tissues in vitro. We first reconstituted the 2D culture conditions for stem cell fate control within 3D hydrogel by incorporating the sets of the diffusible signal molecules delivered through drug-releasing microparticles. Then, utilizing thermo-responsivity of methylcellulose (MC), we developed a cytocompatible casting process to mold these hydrogels into specific 3D configurations, generating the targeted spatial gradients of diffusible signal molecules. The liquid phase of the MC solution was viscous enough to adopt the shapes of 3D impression patterns, while the gelated MC served as a reliable mold for patterning the hydrogel prepolymers. When these patterned hydrogels were integrated together, the stem cells in each hydrogel distinctly differentiated toward individually defined fates, resulting in the formation of the multicellular tissue structure bearing the very structural integrity and characteristics as seen in vascularized bones and osteochondral tissues. PMID:27381562

  10. Fluorescence study on the aggregation of collagen molecules in acid solution influenced by hydroxypropyl methylcellulose.

    PubMed

    Ding, Cuicui; Zhang, Min; Li, Guoying

    2016-01-20

    The effect of hydroxypropyl methylcellulose (HPMC) on the aggregation of collagen molecules with collagen concentrations of 0.25, 0.5 and 1.0mg/mL was studied by fluorescence techniques. On one hand, both the synchronous fluorescence spectra and fluorescence emission spectra showed that there was no change in the fluorescence intensity of collagen intrinsic fluorescence when 30% HPMC was added, while it decreased obviously when HPMC content ≥ 50%. From the two-dimensional fluorescence correlation analysis, it was indicated that collagen molecules in 0.25 and 0.5mg/mL collagen solutions were more sensitive to HPMC than those in 1.0mg/mL collagen solution. On the other hand, the pyrene fluorescence and the fluorescence anisotropy measurements indicated that HPMC inhibited the collagen aggregation for 0.25 and 0.5mg/mL collagen, but promoted it for 1.0mg/mL collagen. The atomic force microscopy images further confirmed the effect of HPMC on collagen with different initial states. PMID:26572350

  11. Processing and characterization of chitosan/PVA and methylcellulose porous scaffolds for tissue engineering.

    PubMed

    Kanimozhi, K; Khaleel Basha, S; Sugantha Kumari, V

    2016-04-01

    Biomimetic porous scaffold chitosan/poly(vinyl alcohol) CS/PVA containing various amounts of methylcellulose (MC) (25%, 50% and 75%) incorporated in CS/PVA blend was successfully produced by a freeze drying method in the present study. The composite porous scaffold membranes were characterized by infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), swelling degree, porosity, degradation of films in Hank's solution and the mechanical properties. Besides these characterizations, the antibacterial activity of the prepared scaffolds was tested, toward the bacterial species Staphylococcus aureus (S.aureus) and Escherichia coli (E.coli). FTIR, XRD and DSC demonstrated that there was strong intermolecular hydrogen bonding between the molecules of CS/PVA and MC. The crystalline microstructure of the scaffold membranes was not well developed. SEM images showed that the morphology and diameter of the scaffolds were mainly affected by the weight ratio of MC. By increasing the MC content in the hybrid scaffolds, their swelling capacity and porosity increased. The mechanical properties of these scaffolds in dry and swollen state were greatly improved with high swelling ratio. The elasticity of films was also significantly improved by the incorporation of MC, and the scaffolds could also bear a relative high tensile strength. These findings suggested that the developed scaffold possess the prerequisites and can be used as a scaffold for tissue engineering. PMID:26838875

  12. 3D patterned stem cell differentiation using thermo-responsive methylcellulose hydrogel molds

    PubMed Central

    Lee, Wonjae; Park, Jon

    2016-01-01

    Tissue-specific patterned stem cell differentiation serves as the basis for the development, remodeling, and regeneration of the multicellular structure of the native tissues. We herein proposed a cytocompatible 3D casting process to recapitulate this patterned stem cell differentiation for reconstructing multicellular tissues in vitro. We first reconstituted the 2D culture conditions for stem cell fate control within 3D hydrogel by incorporating the sets of the diffusible signal molecules delivered through drug-releasing microparticles. Then, utilizing thermo-responsivity of methylcellulose (MC), we developed a cytocompatible casting process to mold these hydrogels into specific 3D configurations, generating the targeted spatial gradients of diffusible signal molecules. The liquid phase of the MC solution was viscous enough to adopt the shapes of 3D impression patterns, while the gelated MC served as a reliable mold for patterning the hydrogel prepolymers. When these patterned hydrogels were integrated together, the stem cells in each hydrogel distinctly differentiated toward individually defined fates, resulting in the formation of the multicellular tissue structure bearing the very structural integrity and characteristics as seen in vascularized bones and osteochondral tissues. PMID:27381562

  13. Development and evaluation of wound healing hydrogels based on a quinolone, hydroxypropyl methylcellulose and biodegradable microfibres.

    PubMed

    Agubata, Chukwuma O; Okereke, Chiadikaobi; Nzekwe, Ifeanyi T; Onoja, Remigius I; Obitte, Nicholas C

    2016-06-30

    Ofloxacin is a synthetic antibiotic of the fluoroquinolone class, with activity against gram-positive and gram-negative bacteria. Wound healing involves a complex interaction of cells and processes which can be improved using appropriate wound- dressing materials. The aim of the present study was to develop and evaluate wound healing hydrogels containing hydroxypropyl methylcellulose (HPMC), ofloxacin and biodegradable microfibres from surgical sutures. The hydrogels were formulated by air-drying mixtures of dilute dispersions of micronized sutures (polyglycolic acid, Vicryl® and catgut), ofloxacin and HPMC gel. The prepared hydrogels were evaluated for gel fraction, swelling capacity, breaking elongation, particle size and morphology, and chemical interactions. Furthermore, in vivo wound healing activities were studied in rats using excision wound model and histological examination. The percentage gel fraction was ≥50% in all the batches, the percentage swelling ratio was within the range of 531.8-1700% and the percentage breaking elongation was found to be in the range of 70-120%. The chemical interaction studies using Fourier Transform Infra Red (FTIR) spectroscopy showed that there was no interaction between the drug and excipients used. Ofloxacin-loaded hydrogels containing dilute microfibres of the sutures showed 95% wound size reduction after fourteen days. These formulations also caused high collagen deposition after twenty one days of wounding, with minimal scar formation. Ofloxacin hydrogels containing HPMC and micronized suture fibres can be applied for effective wound healing. PMID:27094907

  14. Synthesis of surfactant-free hydroxypropyl methylcellulose nanogels for controlled release of insulin.

    PubMed

    Zhao, Di; Shi, Xiaodi; Liu, Tianqun; Lu, Xihua; Qiu, Gao; Shea, Kenneth J

    2016-10-20

    A facile controlled-release nanogels delivery system has been developed by using hydroxypropyl methylcellulose (HPMC) hybrid nanogels as encapsulation shell materials, which were synthesized by surfactant-free polymerization in aqueous solution. The effects of reaction time and cross-linker concentration on the size of the nanogels have been studied. The results showed that in a certain range, the particle size decreased with increasing reaction time and increasing concentration of cross-linker. Meanwhile, at the feeding ratio 0.05/1 of HPMC/methacrylic acid (MAA), the LCST of prepared nanogels at pH=6 was close to the body temperature, which can be used as sustained insulin delivery system. Besides, the HPMC nanogels loaded with insulin had a high drug loading of 21.3% and a high entrapment efficiency of 95.7%. The release behavior of the insulin nanogels can be adjusted by pH and temperature which will have potential applications in controlled release delivery system. PMID:27474648

  15. Photochromic Properties of Tungsten Oxide/Methylcellulose Composite Film Containing Dispersing Agents.

    PubMed

    Yamazaki, Suzuko; Ishida, Hiroki; Shimizu, Dai; Adachi, Kenta

    2015-12-01

    Tungsten oxide-based photochromic films which changed reversibly in air between colorless- transparent in the dark and dark blue under UV irradiation were prepared by using methylcellulose as a film matrix and polyols such as ethylene glycol (EG), propylene glycol (PG), and glycerin (Gly) as dispersing agents. Influence of the dispersing agents and water in the films on the photochromic behavior was systematically studied. Under UV irradiation, absorption bands around 640 and 980 nm increased and the coloring rate was the following order: Gly > EG > PG. An increase in the amounts of dispersing agents or water accelerated the coloring rate. By increasing the water content of the film, a new absorption peak appeared at ca. 775 nm and the Raman spectra indicated a shift of W-O-W stretching vibration to lower wavenumber which was due to the formation of hydrogen bonding. All absorption spectra were fit by three Lorentz functions, whose bands were ascribed to various packing of WO6 octahedra. After the light was turned off, the formation of W(5+) was stopped and bleaching occurred by the reaction with O2 in air to recover its original transparent state. We anticipate that the biodegradable photochromic films developed in this study can be applied in recyclable display medium and especially in detachable films for glass windows whose light transmission properties are changed by sunlight, i.e., for usage as an alternative of smart windows without applying voltage. PMID:26552031

  16. Modeling Anisotropic Self-Assembly of Isotropic Objects: from Hairy Nanoparticles to Methylcellulose Fibrils

    NASA Astrophysics Data System (ADS)

    Ginzburg, Valeriy

    Spontaneous symmetry breaking and formation of anisotropic structures from apparently isotropic building blocks is an exciting and not fully understood topic. I will discuss two examples of such self-assembly. The first example is related to the assembly of ``hairy'' nanoparticles in homopolymer matrices. The particles can assemble into long strings (they can also form other morphologies, as well) even though the shape of each particle and the distribution of ligands on the particle surface is spherically symmetric. Using the approach developed by Thompson, Ginzburg, Matsen, and Balazs, we show that presence of other particles can re-distribute the ligands and effectively ``polarize'' the particle-particle interaction, giving rise to the formation of 1d particle strings. In the second example, we consider aqueous solutions of methylcellulose (MC) polymers. It has been shown recently that at high temperature, the polymers form high-aspect ratio ``fibrils'' with diameter ~15 nm and length in the hundreds on nanometers. Using coarse-grained Molecular Dynamics (CG-MD), we propose that the ``fibrils'' are result of one-dimensional self-assembly of single molecule ``rings''. Each MC polymer chain is forced into a ring because of the balance between internal chain rigidity (favoring more expanded configuration) and unfavorable polymer-water interactions (favoring more collapsed conformation). We also develop a theory predicting rheology and phase behavior of aqueous MC, and validate it against experimental data. Both examples show that anisotropic self-assembly can show up in unexpected places, and various theoretical tools are needed to successfully model it. Funded by The Dow Chemical Company through Grant 223278AF. Collaborators: R. L. Sammler (Dow), W. Huang and R. Larson (U. of Michigan).

  17. Affinity-based release of chondroitinase ABC from a modified methylcellulose hydrogel.

    PubMed

    Pakulska, Malgosia M; Vulic, Katarina; Shoichet, Molly S

    2013-10-10

    Chondroitinase ABC (ChABC) is a promising therapeutic for spinal cord injury as it can degrade the glial scar that is detrimental to regrowth and repair. However, the sustained delivery of bioactive ChABC is a challenge requiring highly invasive methods such as intra-spinal injections, insertion of intrathecal catheters, or implantation of delivery vehicles directly into the tissue. ChABC is thermally unstable, further complicating its delivery. Moreover, there are no commercial antibodies available for its detection. To achieve controlled release, we designed an affinity-based system that sustained the release of bioactive ChABC for at least 7days. ChABC was recombinantly expressed as a fusion protein with Src homology domain 3 (SH3) with an N-terminal histidine (HIS) tag and a C-terminal FLAG tag (ChABC-SH3). Protein purification was achieved using a nickel affinity column and, for the first time, direct quantification of ChABC down to 0.1nM was attained using an in-house HIS/FLAG double tag ELISA. The release of active ChABC-SH3 was sustained from a methylcellulose hydrogel covalently modified with an SH3 binding peptide. The rate of release was tunable by varying either the binding strength of the SH3-protein/SH3-peptide pair or the SH3-peptide to SH3-protein ratio. This innovative system has the potential to be used as a platform technology for the release and detection of other proteins that can be expressed using a similar construct. PMID:23831055

  18. Effects of Methylcellulose on Fibrolytic Bacterial Detachment and In vitro Degradation of Rice Straw.

    PubMed

    Kim, Min Ji; Sung, Ha Guyn; Upadhaya, Santi Devi; Ha, Jong K; Lee, Sung Sill

    2013-10-01

    Two in vitro experiments were conducted to evaluate the effect of methylcellulose (MC) on i) bacterial detachment from rice straw as well as ii) inhibition of bacterial attachment and fiber digestibility. To evaluate the effect of MC on fibrolytic bacterial detachment (Exp 1), in vitro bacterial cultures with 0.1% (w/v) MC solution were compared with cultures without MC after 8 h incubation. The effect of MC on inhibition of bacterial attachment was determined by comparing with real-time PCR the populations of F. succinogenes, R. flavefaciens and R. albus established on rice straw pre-treated with 0.1% MC with those on untreated straw after incubation for 0, 6 and 12 h (Exp 2). The major fibrolytic bacterial attachment on rice straw showed significantly lower populations with either the addition of MC to the culture or pre-treated rice straw compared to controls (p<0.05). Also, the digestibility of rice straw with MC was significantly lower compared with control (p<0.05). The F. succinogenes population did not show detachment from rice straw, but showed an inhibition of attachment and proliferation on rice straw in accordance with a decrease of fiber digestion. The detachments of Ruminococcus species co-existed preventing the proliferations with subsequent reduction of fiber degradation by MC during the incubation. Their detachments were induced from stable colonization as well as the initial adhesion on rice straw by MC in in vitro ruminal fermentation. Furthermore, the detachment of R. albus was more sensitive to MC than was R. flavefaciens. These results showed the certain evidence that attachment of major fibrolytic bacteria had an effect on fiber digestion in the rumen, and each of fibrolytic bacteria, F. succinogenes, R. flavefaciens and R. albus had a specific mechanism of attachment and detachment to fiber. PMID:25049729

  19. Effects of Methylcellulose on Fibrolytic Bacterial Detachment and In vitro Degradation of Rice Straw

    PubMed Central

    Kim, Min Ji; Sung, Ha Guyn; Upadhaya, Santi Devi; Ha, Jong K.; Lee, Sung Sill

    2013-01-01

    Two in vitro experiments were conducted to evaluate the effect of methylcellulose (MC) on i) bacterial detachment from rice straw as well as ii) inhibition of bacterial attachment and fiber digestibility. To evaluate the effect of MC on fibrolytic bacterial detachment (Exp 1), in vitro bacterial cultures with 0.1% (w/v) MC solution were compared with cultures without MC after 8 h incubation. The effect of MC on inhibition of bacterial attachment was determined by comparing with real-time PCR the populations of F. succinogenes, R. flavefaciens and R. albus established on rice straw pre-treated with 0.1% MC with those on untreated straw after incubation for 0, 6 and 12 h (Exp 2). The major fibrolytic bacterial attachment on rice straw showed significantly lower populations with either the addition of MC to the culture or pre-treated rice straw compared to controls (p<0.05). Also, the digestibility of rice straw with MC was significantly lower compared with control (p<0.05). The F. succinogenes population did not show detachment from rice straw, but showed an inhibition of attachment and proliferation on rice straw in accordance with a decrease of fiber digestion. The detachments of Ruminococcus species co-existed preventing the proliferations with subsequent reduction of fiber degradation by MC during the incubation. Their detachments were induced from stable colonization as well as the initial adhesion on rice straw by MC in in vitro ruminal fermentation. Furthermore, the detachment of R. albus was more sensitive to MC than was R. flavefaciens. These results showed the certain evidence that attachment of major fibrolytic bacteria had an effect on fiber digestion in the rumen, and each of fibrolytic bacteria, F. succinogenes, R. flavefaciens and R. albus had a specific mechanism of attachment and detachment to fiber. PMID:25049729

  20. Thermo-responsive methylcellulose hydrogels as temporary substrate for cell sheet biofabrication.

    PubMed

    Altomare, Lina; Cochis, Andrea; Carletta, Andrea; Rimondini, Lia; Farè, Silvia

    2016-05-01

    Methylcellulose (MC), a water-soluble polymer derived from cellulose, was investigated as a possible temporary substrate having thermo-responsive properties favorable for cell culturing. MC-based hydrogels were prepared by a dispersion technique, mixing MC powder (2, 4, 6, 8, 10, 12 % w/v) with selected salts (sodium sulphate, Na2SO4), sodium phosphate, calcium chloride, or phosphate buffered saline, to evaluate the influence of different compositions on the thermo-responsive behavior. The inversion test was used to determine the gelation temperatures of the different hydrogel compositions; thermo-mechanical properties and thermo-reversibility of the MC hydrogels were investigated by rheological analysis. Gelation temperatures and rheological behavior depended on the MC concentration and type and concentration of salt used in hydrogel preparation. In vitro cytotoxicity tests, performed using L929 mouse fibroblasts, showed no toxic release from all the tested hydrogels. Among the investigated compositions, the hydrogel composed of 8 % w/v MC with 0.05 M Na2SO4 had a thermo-reversibility temperature at 37 °C. For that reason, this formulation was thus considered to verify the possibility of inducing in vitro spontaneous detachment of cells previously seeded on the hydrogel surface. A continuous cell layer (cell sheet) was allowed to grow and then detached from the hydrogel surface without the use of enzymes, thanks to the thermo-responsive behavior of the MC hydrogel. Immunofluorescence observation confirmed that the detached cell sheet was composed of closely interacting cells. PMID:26984360

  1. Effect of methylcellulose on the formation and drug release behavior of silk fibroin hydrogel.

    PubMed

    Park, Cho Hee; Jeong, Lim; Cho, Donghwan; Kwon, Oh Hyeong; Park, Won Ho

    2013-10-15

    In this study, methylcellulose (MC) was used to control the gelation time of silk fibroin (SF) aqueous solution. The gelation time was measured using a Vibro Viscometer at 50 °C. Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and a texture meter were used to investigate the effect of MC on the hydrogelation of SF solution. SF/MC hydrogels could be formed by the addition of MC, although their gelation time was increased with MC content. To examine the conformational change of SF/MC hydrogels, time-resolved FT-IR spectra were obtained at constant temperature using a custom-made IR chamber. From FT-IR spectra focused on the amide I peak position, the transition of SF molecules in SF/MC solution from a random coil to a β-sheet structure was inhibited in the presence of MC molecules. In addition, the drug release of SF/MC hydrogels loaded with 5-aminosalicylic acid was studied in 2-dimensional (2-D) and 3-dimensional (3-D) conditions in vitro. The drug release behavior of SF or SF/MC hydrogels was measured using UV-Vis spectroscopy. The release rate of 5-aminosalicylic acid in SF/MC hydrogel was lower than that of SF hydrogel, which may be closely associated with the hydrophilic interaction between MC and 5-aminosalicylic acid. This approach to controlling the sol-gel transition and the drug release of SF hydrogels by the addition of MC will be useful in the design and tailoring of novel materials for biomedical applications. PMID:23987461

  2. Physicochemical and morphological properties of poly (acrylamide) and methylcellulose hydrogels: rffects of monomer, crosslinker and polysaccharide compositions, polymer engineering and science

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper describes the physicochemical (mechanical and swelling) and morphological characterization of poly (acrylamide) and methylcellulose (PAAm-MC) hydrogels synthesized with different formulations by the free radical polymerization method. The structure-property relationship of the PAAm-MC hyd...

  3. Physical and sensory properties of all-barley and all-oat breads with additional hydroxypropyl methylcellulose (HPMC) ß-glucan

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hydroxypropyl methylcellulose (HPMC) is a substituted cellulose that reduces serum cholesterol at modest intake levels. HPMC has also been used for decades in gluten-free breads at a level to optimize loaf volume. Because consumers resist the consumption of whole wheat breads, we evaluated the sen...

  4. Ibuprofen microencapsulation within acrylamide-grafted chitosan and methylcellulose interpenetrating polymer network microspheres: Synthesis, characterization, and release studies.

    PubMed

    Bulut, Emine

    2016-06-01

    This study deals with the development of interpenetrating polymer network (IPN) microspheres of acrylamide (AAm) grafted onto a chitosan (CS) backbone and methylcellulose (MC). Chitosan-graft-polyacrylamide (CS-g-PAAm) was synthesized by cerium (IV) ammonium nitrate-induced free radical graft polymerization. The grafting percentage was found to be 50.58%. The synthesized graft copolymer and MC were used to prepare microspheres by the water-in-oil (w/o) emulsion-crosslinking method, and crosslinked with glutaraldehyde (GA) as drug delivery matrices of ibuprofen (IBU). The release of IBU from microspheres decreased when the amount of CS-g-PAAm in the polymer matrix and amount of crosslinker added were increased, while it increased with the increase of the IBU/polymer ratio. PMID:25749277

  5. Durability and synergistic effects of KI on the acid corrosion inhibition of mild steel by hydroxypropyl methylcellulose.

    PubMed

    Arukalam, I O

    2014-11-01

    The performance of hydroxypropyl methylcellulose (HPMC) as safe corrosion inhibitor for mild steel in aerated 0.5M H2SO4 solution was appraised by weight loss, impedance and polarization measurements. Results indicate that HPMC functions as a good inhibitor in the studied environment and inhibition efficiency increased with increasing concentration of inhibitor and temperature. Time-dependent effect of the inhibition efficiency reveals that inhibition efficiency increased with time up to the fourth day after which it waned, but improved on addition of KI. The synergism parameter evaluated confirmed the synergistic effect of KI and HPMC. Impedance results clearly show that HPMC inhibited the corrosion reaction via adsorption onto the metal/solution interface following Freundlich adsorption isotherm. Polarization results indicate that HPMC acts as a mixed-type inhibitor with predominant cathodic effect. Theoretical study using density functional theory was employed to establish the correlation between the structure (molecular and electronic) and the inhibition efficiency. PMID:25129747

  6. Edible films from methylcellulose and nanoemulsions of clove bud (Syzygium aromaticum) and oregano (Origanum vulgare) essential oils as shelf life extenders for sliced bread.

    PubMed

    Otoni, Caio G; Pontes, Silvania F O; Medeiros, Eber A A; Soares, Nilda de F F

    2014-06-01

    Consumers are increasingly demanding foods with lower synthetic preservatives. Plant essential oils are natural compounds with remarkable antimicrobial properties and may be incorporated as emulsions into water-soluble polymers to form antimicrobial films. Coarse emulsions (diameters of 1.3-1.9 μm) and nanoemulsions (diameters of 180-250 nm) of clove bud (Syzygium aromaticum) and oregano (Origanum vulgare) essential oils were produced through low-speed mixing and ultrasonication, respectively. Methylcellulose was added for film-forming purposes. Both essential oils reduced the rigidity and increased the extensibility of the methylcellulose films, effects that were even more pronounced for nanodroplets. Both essential oils lessened the counts of yeasts and molds in sliced bread during 15 days, and droplet size reduction provided a further improvement in antimicrobial properties. Due to increased bioavailability, less preservative content might be used and still deliver the same antimicrobial efficiency if encapsulated in smaller particles. PMID:24815228

  7. Rheological response of methylcellulose toward alkanediyl-α,ω-bis(dimethylcetylammonium bromide) surfactants with varying spacer length.

    PubMed

    Shah, Rais Ahmad; Chat, Oyais Ahmad; Maswal, Masrat; Rather, Ghulam Mohammad; Dar, Aijaz Ahmad

    2016-06-25

    The modulation of properties of methylcellulose (MC) by cationic gemini surfactants with varying spacer lengths was studied employing tensiometry, rheometry and turbidimetry. Surface tension measurements anticipate that the gemini surfactant with longer spacer chain length saturates MC at lower concentrations owing to its greater hydrophobicity compared to shorter spacer analogues. Rheometric and turbidimetric measurements suggest that at very low concentrations of gemini surfactants, ion-dipole type of interactions between MC and gemini surfactants promote the extension of polymer chains which is manifested by an initial increase in the low shear viscosity and gelation temperature of MC-gemini surfactant systems, and lowering of turbidity. Such interactions were found to be stronger in case of 16-4-16 than 16-5-16, and almost absent in case of 16-6-16 surfactant system. However at concentrations above CAC, hydrophobic forces operative between MC and gemini surfactants were found to be more for 16-6-16 than that of 16-5-16 and 16-4-16. The final levelling of MC viscosity in presence of all the three gemini surfactants and the variation of gelation temperature suggests the solubilization of network junctions in the surfactant micelles. Moreover, the presence of gemini surfactant strongly affects the interaction of MC with a model hydrophobic drug rifampicin.The results highlight the importance of gemini surfactants and their spacer length in controlling the structural dynamics of MC and its effective use in pharmaceutical and food industry. PMID:27083805

  8. In Situ Observations of Thermoreversible Gelation and Phase Separation of Agarose and Methylcellulose Solutions under High Pressure.

    PubMed

    Kometani, Noritsugu; Tanabe, Masahiro; Su, Lei; Yang, Kun; Nishinari, Katsuyoshi

    2015-06-01

    Thermoreversible sol-gel transitions of agarose and methylcellulose (MC) aqueous solutions on isobaric cooling or heating under high pressure up to 400 MPa have been investigated by in situ observations of optical transmittance and falling-ball experiments. For agarose, which undergoes the gelation on cooling, the application of pressure caused a gradual rise in the cloud-point temperature over the whole pressure range examined, which is almost consistent with the pressure dependence of gelling temperature estimated by falling-ball experiments, suggesting that agarose gel is stabilized by compression and that the gelation occurs nearly in parallel with phase separation under ambient and high-pressure conditions. For MC, which undergoes the gelation on heating, the cloud-point temperature showed a slight rise with an initial elevation of pressure up to ∼150 MPa, whereas it showed a marked depression above 200 MPa. In contrast, the gelling temperature of MC, which is nearly identical to the cloud-point temperature at ambient pressure, showed a monotonous rise with increasing pressure up to 350 MPa, which means that MC undergoes phase separation prior to gelation on heating under high pressure above 200 MPa. Similar results were obtained for the melting process of MC gel on cooling. The unique behavior of the sol-gel transition of MC under high pressure has been interpreted in terms of the destruction of hydrophobic hydration by compression. PMID:25984597

  9. The influence of substituted phenols on the sol:gel transition of hydroxypropyl methylcellulose (HPMC) aqueous solutions.

    PubMed

    Banks, Simon R; Pygall, Samuel R; Bajwa, Gurjit S; Doughty, Stephen W; Timmins, Peter; Melia, Colin D

    2014-01-30

    The influence of the physicochemical parameters of substituted aromatic molecules on the phase transition from sol to gel of hydroxypropyl methylcellulose (HPMC) has been investigated using a homologous series of substituted phenols. Using a turbimetric methodology, concentration dependent suppression of phase transition temperature of HPMC was observed for phenol and its derivatives, including methyl-, nitro- and chloro-substituted molecules. Although no strong direct relationship between single molecular physicochemical properties of the phenolic compounds (such as pKa, LogP and other molecular descriptors) and ΔCPT was found for the compounds tested, a successful prediction of behaviour could be obtained by using a combination of parameters. This suggested that the interaction mechanism between HPMC and the substituted aromatic moiety is a complex summation of the different molecular physicochemical properties. Identification of these potentially deleterious chemical moieties may be of value in a pharmaceutical context when considering preformulation of drug structures containing them. An incompatibility between drug and polymer may be indicative of deleterious effects resulting from formulation with hydrophilic matrix dosage forms containing cellulose ethers such as HPMC. PMID:24299892

  10. A novel white film for pharmaceutical coating formed by interaction of calcium lactate pentahydrate with hydroxypropyl methylcellulose.

    PubMed

    Sakata, Yukoh; Shiraishi, Sumihiro; Otsuka, Makoto

    2006-07-24

    We have found that a white film forms on tablets when a coating solution consisting of hydroxypropyl methylcellulose (HPMC), polyethylene glycol (PEG 6000) and calcium lactate pentahydrate (CLP) is used. The white film has also been found in casting film consisting of HPMC and CLP, and the surface state of coated tablets has been shown to be strongly affected by addition of PEG 6000. The aim of the present study was to investigate the mechanism of formation of this white film in order to derive an appropriate film prescription. Interaction among the base ingredients of the film was investigated using differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and Fourier transform-infrared (FT-IR) spectroscopy. The casting film formed with HPMC and a large excess of PEG 6000 was found to be crystalline in form. In contrast, the amorphous film consisting of HPMC, PEG 6000 and excess CLP exhibited the crystallinity film by an excess addition of CLP. Although the crystalline film had many cracks, the amorphous film appeared to be excellent as a tablet coating. The most probable interaction sites between HPMC and CLP were demonstrated by FT-IR analysis of casting films consisting of HPMC, CLP and PVP. PMID:16621357

  11. Optimization and Evaluation of a Chitosan/Hydroxypropyl Methylcellulose Hydrogel Containing Toluidine Blue O for Antimicrobial Photodynamic Inactivation

    PubMed Central

    Chen, Chueh-Pin; Hsieh, Chien-Ming; Tsai, Tsuimin; Yang, Jen-Chang; Chen, Chin-Tin

    2015-01-01

    Photodynamic inactivation (PDI) combined with chitosan has been shown as a promising antimicrobial approach. The purpose of this study was to develop a chitosan hydrogel containing hydroxypropyl methylcellulose (HPMC), chitosan and toluidine blue O (TBO) to improve the bactericidal efficacy for topical application in clinics. The PDI efficacy of hydrogel was examined in vitro against the biofilms of Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa). Confocal scanning laser microscopy (CSLM) was performed to investigate the penetration level of TBO into viable S. aureus biofilms. Incorporation of HMPC could increase the physicochemical properties of chitosan hydrogel including the hardness, viscosity as well as bioadhesion; however, higher HMPC concentration also resulted in reduced antimicrobial effect. CSLM analysis further demonstrated that higher HPMC concentration constrained TBO diffusion into the biofilm. The incubation of biofilm and hydrogel was further performed at an angle of 90 degrees. After light irradiation, compared to the mixture of TBO and chitosan, the hydrogel treated sample showed increased PDI efficacy indicated that incorporation of HPMC did improve antimicrobial effect. Finally, the bactericidal efficacy could be significantly augmented by prolonged retention of hydrogel in the biofilm as well as in the animal model of rat skin burn wounds after light irradiation. PMID:26340623

  12. Pharmacokinetic and milk penetration of a difloxacin long-acting poloxamer gel formulation with carboxy-methylcellulose in lactating goats.

    PubMed

    Escudero, Elisa; Marín, Pedro; Cárceles, Carlos M; Ramírez, María J; Fernández-Varón, Emilio

    2011-04-01

    The single-dose disposition kinetics of difloxacin were determined in clinically normal lactating goats (n=6) after subcutaneous administration of a long-acting poloxamer 407 gel formulation with carboxy-methylcellulose (P407-CMC). Difloxacin concentrations were determined by high performance liquid chromatography with fluorescence detection. The concentration-time data were analysed by non-compartmental kinetic methods. Plasma and milk elimination half-lives after P407-CMC dosing were 35.19 h and 33.93 h, respectively. With this formulation, difloxacin achieved maximum plasma concentrations of 2.67±0.34 mg/L at 2.92±1.20 h and maximum milk concentrations of 2.31±0.35 mg/L at 4.00±0.00 h. The area under the curve (AUC) ratio AUC(milk)/AUC(plasma) was 0.89 after P407-CMC administration. It was concluded that a 15 mg/kg dose of difloxacin within P407-CMC would be effective against mastitis pathogens with a minimum inhibitory concentration (MIC)≤0.12 mg/L. PMID:20359917

  13. Gelatin-hydroxypropyl methylcellulose water-in-water emulsions as a new bio-based packaging material.

    PubMed

    Esteghlal, Sara; Niakosari, Mehrdad; Hosseini, Seyed Mohammad Hashem; Mesbahi, Gholam Reza; Yousefi, Gholam Hossein

    2016-05-01

    Gelatin and hydroxypropyl methylcellulose (HPMC) are two incompatible and immiscible biopolymers which cannot form homogeneous composite films using usual methods. In this study, to prevent phase separation, gelatin-HPMC water-in-water (W/W) emulsion was utilized to from transparent composite films by entrapment the HPMC dispersed droplets in gelatin continuous network. The physicochemical and mechanical properties of emulsion-based films containing different amounts (5-30%) of dispersed phase were determined and compared with those of individual polymer-based films. Incorporating HPMC into W/W emulsion-based films had no significant effect on the tensile strength. The flexibility of composite films decreased at HPMC concentrations below 20%. The depletion layer at the droplets interface reduced the diffusion of water vapor molecules because of its hydrophobic nature, so the water vapor permeability remained constant. Increasing the HPMC content in the emulsion films increased the swelling and decreased the transparency. The entrapment of HPMC in continuous gelatin phase decreased its solubility. Therefore, W/W emulsions are capable of holding two incompatible polymers alongside each other within a homogeneous film network without weakening the physical properties. PMID:26808017

  14. Injectable cell constructs fabricated via culture on a thermoresponsive methylcellulose hydrogel system for the treatment of ischemic diseases.

    PubMed

    Huang, Chieh-Cheng; Liao, Zi-Xian; Chen, Ding-Yuan; Hsiao, Chun-Wen; Chang, Yen; Sung, Hsing-Wen

    2014-08-01

    Cell transplantation via direct intramuscular injection is a promising therapy for patients with ischemic diseases. However, following injections, retention of transplanted cells in engrafted areas remains problematic, and can be deleterious to cell-transplantation therapy. In this Progress Report, a thermoresponsive hydrogel system composed of aqueous methylcellulose (MC) blended with phosphate-buffered saline is constructed to grow cell sheet fragments and cell bodies for the treatment of ischemic diseases. The as-prepared MC hydrogel system undergoes a sol-gel reversible transition upon heating or cooling at ≈32 °C. Via this unique property, the grown cell sheet fragments (cell bodies) can be harvested without using proteolytic enzymes; consequently, their inherent extracellular matrices (ECMs) and integrative adhesive agents remain well preserved. In animal studies using rats and pigs with experimentally created myocardial infarction, the injected cell sheet fragments (cell bodies) become entrapped in the interstices of muscular tissues and adhere to engraftment sites, while a minimal number of cells exist in the group receiving dissociated cells. Moreover, transplantation of cell sheet fragments (cell bodies) significantly increases vascular density, thereby improving the function of an infarcted heart. These experimental results demonstrate that cell sheet fragments (cell bodies) function as a cell-delivery construct by providing a favorable ECM environment to retain transplanted cells locally and consequently, improving the efficacy of therapeutic cell transplantation. PMID:24470263

  15. Preparation and performance of hydroxypropyl methylcellulose esters of substituted succinates for in vitro supersaturation of a crystalline hydrophobic drug.

    PubMed

    Yin, Ligeng; Hillmyer, Marc A

    2014-01-01

    We prepared hydroxypropyl methylcellulose (HPMC) esters of substituted succinates and examined their performance for improving the aqueous solubility of crystalline hydrophobic drugs in spray-dried dispersions (SDDs). From one HPMC, we synthesized five HPMC esters using various monosubstituted succinic anhydrides. These HPMC esters along with a commercial HPMC acetate succinate (HPMCAS) were spray-dried from solutions with phenytoin. The SDDs with different matrices at 10 wt % loading had very similar bulk properties with a minimal amount of detectable crystalline phenytoin as revealed by scanning electron microscopy (SEM), powder X-ray diffraction (powder XRD), and differential scanning calorimetry (DSC). In solution, while the SDD with HPMCAS was very effective at achieving high levels of phenytoin supersaturation initially, it was not competent at maintaining such supersaturation due to the rapid crystallization of the dissolved phenytoin. Alternatively, SDDs with several synthesized HPMC esters of substituted succinates not only achieved rather high initial supersaturation but also maintained high concentrations for extended time (i.e., 1.5 h and longer). Such maintenance was largely ascribed to the inhibition of phenytoin nucleation. Structure-property relationships were established, and the most successful systems contained a high degree of substitution and a combination of a thioether with neighboring weak electron-withdrawing groups in the substituted succinic anhydrides. The effective maintenance of supersaturated solutions was only found in SDDs with rather low drug loadings, which indicates the significance of sufficiently high concentrations of polymer additives in the dissolution media. PMID:24320108

  16. Effects of ultrasound treatment on lipid self-association and properties of methylcellulose/stearic acid blending films.

    PubMed

    Zhong, Tian; Huang, Ran; Sui, Siyao; Lian, Zixuan; Sun, Xiuxiu; Wan, Ajun; Li, Huili

    2015-10-20

    The effects of ultrasound treatment (UT) on the properties of methylcellulose (MC)/stearic acid (SA) blending films were studied. Film-forming emulsions were prepared with different UT conditions and characterized with respect to viscosity. The lipid aggregation and distribution in the blending dispersions were studied by the micrographs of Transmission Electron Microscopy (TEM). The micrographs of both surface and cross-section of the films were observed by scanning electron microscope (SEM) and the tensile strength (TS), elongation at break (E), water vapor permeability (WVP) and contact angles of the resulting films were determined as well. The intensification of the UT condition led to a decrease of viscosity of the MC-SA blending emulsions, a more homogeneous lipid distribution and a denser internal microstructure of the resulting films. UT exposure affected the mechanical, moisture barrier and surface hydrophobic properties. The optimal values of both TS and E was obtained from the sample treated for 10min and 180W power, while the sample treated for 10min and 270W presented the lowest value of WVP. However, an excessive exposure of UT led to a decrease of the mechanical and moisture barrier performance. By observing and analyzing the SEM graphs and the contact angles of the film surfaces, it was found that UT within the appropriate bounds had a notably positive effect on improving the surface hydrophobic property of the MC-SA blending films. PMID:26256202

  17. Extended release of high molecular weight hydroxypropyl methylcellulose from molecularly imprinted, extended wear silicone hydrogel contact lenses.

    PubMed

    White, Charles J; McBride, Matthew K; Pate, Kayla M; Tieppo, Arianna; Byrne, Mark E

    2011-08-01

    Symptoms of contact lenses induced dry eye (CLIDE) are typically treated through application of macromolecular re-wetting agents via eye drops. Therapeutic soft contact lenses can be formulated to alleviate CLIDE symptoms by slowly releasing comfort agent from the lens. In this paper, we present an extended wear silicone hydrogel contact lens with extended, controllable release of 120 kDa hydroxypropyl methylcellulose (HPMC) using a molecular imprinting strategy. A commercial silicone hydrogel lens was tailored to release approximately 1000 μg of HPMC over a period of up to 60 days in a constant manner at a rate of 16 μg/day under physiological flowrates, releasing over the entire range of continuous wear. Release rates could be significantly varied by the imprinting effect and functional monomer to template ratio (M/T) with M/T values 0, 0.2, 2.8, 3.4 corresponding to HPMC release durations of 10, 13, 23, and 53 days, respectively. Lenses had high optical quality and adequate mechanical properties for contact lens use. This work highlights the potential of imprinting in the design and engineering of silicone hydrogel lenses to release macromolecules for the duration of wear, which may lead to decreased CLIDE symptoms and more comfortable contact lenses. PMID:21601274

  18. Injectable thermo-responsive hydrogel composed of xanthan gum and methylcellulose double networks with shear-thinning property.

    PubMed

    Liu, Zhijia; Yao, Ping

    2015-11-01

    Injectable hydrogel precursor solution was prepared by physical blend of xanthan gum (XG) and methylcellulose (MC) in aqueous solution. Due to the formation of XG network composed of XG double helical strand structure, XG/MC blend was a high viscous solution with good shear-thinning property at room temperature. When the temperature was changed from 23 to 37 °C, thermo-responsive MC network formed, which caused XG/MC blend solution to gelate. The gelation time and storage modulus of the blend can be tuned by XG and/or MC concentrations. Both in vitro and in vivo investigations revealed that the blend solution immediately recovered its high viscosity and rapidly formed hydrogel at body temperature after injection using a syringe. In vivo biocompatibility and biodegradability of the hydrogel were validated by implantation of the hydrogel in rats. In vitro investigation demonstrated that XG/MC blend is a promising injectable hydrogel material for long-term drug delivery. PMID:26256374

  19. Modification and characterization of biodegradable methylcellulose films with trimethylolpropane trimethacrylate (TMPTMA) by γ radiation: effect of nanocrystalline cellulose.

    PubMed

    Sharmin, Nusrat; Khan, Ruhul A; Salmieri, Stephane; Dussault, Dominic; Bouchard, Jean; Lacroix, Monique

    2012-01-18

    Methylcellulose (MC)-based films were prepared by solution casting from its 1% aqueous suspension containing 0.25% glycerol. Trimethylolpropane trimethacrylate (TMPTMA) monomer (0.1-2% by wt) along with the glycerol was added to the MC suspension. The films were cast and irradiated from a radiation dose varied from 0.1 to 10 kGy. Then the mechanical properties such as tensile strength (TS), tensile modulus (TM), and elongation at break (Eb) and barrier properties of the films were evaluated. The highest TS (47.88 PMa) and TM (1791.50 MPa) of the films were found by using 0.1% monomer at 5 kGy dose. The lowest water vapor permeability (WVP) of the films was found to be 5.57 g·mm/m(2)·day·kPa (at 0.1% monomer and 5 kGy dose), which is 12.14% lower than control MC-based films. Molecular interactions due to incorporation of TMPTMA were supported by FTIR spectroscopy. A band at 1720 cm(-1) was observed due to the addition of TMPTMA in MC-based films, which indicated the typical (C═O) carbonyl stretching. For the further improvement of the mechanical and barrier properties of the film, 0.025-1% nanocrystalline cellulose (NCC) was added to the MC-based suspension containing 1% TMPTMA. Addition of NCC led to a significant improvement in the mechanical and barrier properties. The novelty of this investigation was to graft insoluble monomer using γ radiation with MC-based films and use of biodegradable NCC as the reinforcing agent. PMID:22217269

  20. Preparation, characterization and in vitro drug release of poly-epsilon-caprolactone and hydroxypropyl methylcellulose phthalate ketoprofen loaded microspheres.

    PubMed

    Guzman, M; Molpeceres, J; Garcia, F; Aberturas, M R

    1996-01-01

    Ketoprofen was encapsulated within poly-epsilon-caprolactone (PCL) and hydroxypropyl methylcellulose phthalate 50 (HPMCP50) microspheres (MS). Scanning electron microscopy (SEM) studies showed spherical particles without surface crystal formation and differential scanning calorimetry (DSC) supported these results. MS of PCL or HPMCP50 had a mean particle size of 10.7 +/- 2.2 and 10.9 +/- 2.0 mu m respectively, whereas a mixture of these polymers increased the MS particle size to 30 mu m. Greater incorporation efficiencies were found for HPMCP50 MS (98.1 +/- 0.7). MS of PCL and HPMCP50 mixtures showed a decreased drug entrapment as the amount of PCL was increased (96.0 +/- 0.2 for 25% PCL, 95.6 +/- 1.8 for 50% PCL, 80.2 +/- 0.7 for 75% PCL and 78.9 +/- 9.0 for 100% PCL). Size exclusion chromatography (SEC) studies revealed a weak interaction between ketoprofen and PCL and some polymer degradation was found during HPMCP50 MS storage, probably by breaking of the phthalic anhydride bond to be anyhydroglucose backbone. Four types of cryoprotectors (glucose, trehalose, mannitol and sorbitol, at 5 and 10% W/V) and two freezing conditions (-196 and -20 degrees C) were evaluated in freeze-drying studies. For HPMCP50, the sizes of MS after reconstitution of liophylizates were nearly the same as the initial ones. For PCL MS only, those formulations with sorbitol or glucose at 10% and frozen at -196 degrees C showed acceptable results. In contrast to the rapid release rate of ketoprofen from PCL MS as a result of carrier porosity (80% released within 15 min), the release from HPMCP50 MS could be controlled by means of pH (40% released in the first 15 min in simulated gastric fluid and nearly 100% ketoprofen delivered in the same time in simulated intestinal fluid). PMID:8903783

  1. Equilibrium state at supersaturated drug concentration achieved by hydroxypropyl methylcellulose acetate succinate: molecular characterization using (1)H NMR technique.

    PubMed

    Ueda, Keisuke; Higashi, Kenjirou; Yamamoto, Keiji; Moribe, Kunikazu

    2015-04-01

    The maintenance mechanism of the supersaturated state of poorly water-soluble drugs, glibenclamide (GLB) and chlorthalidone (CLT), in hydroxypropyl methylcellulose acetate succinate (HPMC-AS) solution was investigated at a molecular level. HPMC-AS suppressed drug crystallization from supersaturated drug solution and maintained high supersaturated level of drugs with small amount of HPMC-AS for 24 h. However, the dissolution of crystalline GLB into HPMC-AS solution failed to produce supersaturated concentrations, although supersaturated concentrations were achieved by adding amorphous GLB to HPMC-AS solution. HPMC-AS did not improve drug dissolution and/or solubility but efficiently inhibited drug crystallization from supersaturated drug solutions. Such an inhibiting effect led to the long-term maintenance of the amorphous state of GLB in HPMC-AS solution. NMR measurements showed that HPMC-AS suppressed the molecular mobility of CLT depending on their supersaturation level. Highly supersaturated CLT in HPMC-AS solution formed a gel-like structure with HPMC-AS in which the molecular mobility of the CLT was strongly suppressed. The gel-like structure of HPMC-AS could inhibit the reorganization from drug prenuclear aggregates to the crystal nuclei and delay the formation of drug crystals. The prolongation subsequently led to the redissolution of the aggregated drugs in aqueous solution and formed the equilibrium state at the supersaturated drug concentration in HPMC-AS solution. The equilibrium state formation of supersaturated drugs by HPMC-AS should be an essential mechanism underlying the marked drug concentration improvement. PMID:25723893

  2. Factorial designed 5-fluorouracil-loaded microsponges and calcium pectinate beads plugged in hydroxypropyl methylcellulose capsules for colorectal cancer

    PubMed Central

    Gupta, Ankita; Tiwari, Gaurav; Tiwari, Ruchi; Srivastava, Rishabh

    2015-01-01

    Introduction: The work was aimed to develop an enteric-coated hydroxypropyl methylcellulose (HPMC) capsules (ECHC) plugged with 5-fluorouracil (5-FU)-loaded microsponges in combination with calcium pectinate beads. Materials and Methods: The modified quasi-emulsion solvent diffusion method was used to prepare microsponges. A 32 factorial design was employed to study the formulation and the effects of independent variables (volume of organic solvent and Eudragit-RS100 content) on dependent variables (particle size, %entrapment efficiency, and %cumulative drug release). The optimized microsponge (F4) was characterized by scanning electron microscopy, powder X-ray diffraction, and thermogravimetric analysis. F4 was plugged along with the calcium pectinate beads in HPMC capsules coated with enteric polymer Eudragit-L100 (Ed-L100) and/or Eudragit-S100 (Ed-S100) in different proportions. An in vitro release study of ECHC was performed in simulated gastric fluid for 2 h, followed by simulated intestinal fluid for next 6 h and then in simulated colonic fluid (in the presence and absence of pectinase enzyme for further 16 h). The optimized formulation was subjected to in vivo roentgenographic and pharmacokinetic studies in New Zealand white rabbits to analyze the in vivo behavior of the developed colon-targeted capsules. Results: Drug release was retarded on coating with Ed-S100 in comparison to a blend of Ed-S100:Ed-L100 coating. The percentage of 5-FU released at the end of 24 h from ECHC3 was 97.83 ± 0.12% in the presence of pectinase whereas in the control study, it was 40.08 ± 0.02%. Conclusion: Thus, enteric-coated HPMC capsules plugged with 5-FU-loaded microsponges and calcium pectinate beads proved to be a promising dosage form for colon targeting. PMID:26682194

  3. Preparation of magnetite-chitosan/methylcellulose nanospheres by entrapment and adsorption techniques for targeting the anti-cancer drug 5-fluorouracil.

    PubMed

    Şanlı, Oya; Kahraman, Aslı; Kondolot Solak, Ebru; Olukman, Merve

    2016-05-01

    In this work, we have formulated novel nanospheres that could be used in the controlled release of the anticancer drug, 5-fluorouracil (5-FU). The nanospheres are composed of magnetite, containing chitosan (CS) and methylcellulose (MC). The drug entrapment was achieved through the encapsulation and adsorption processes. The effects of the preparation conditions, such as magnetite content, CS/MC ratio, crosslinking concentration, exposure time to glutaraldehyde (GA), and the drug/polymer ratio were investigated for both processes. The 5-FU release was found to follow the Fickian mechanism, and the Langmuir isotherm for the nanospheres was achieved through encapsulation and adsorption processes, respectively. PMID:25677468

  4. Physical and sensory properties of all-barley and all-oat breads with additional hydroxypropyl methylcellulose (HPMC) β-glucan.

    PubMed

    Kim, Yookyung; Yokoyama, Wallace H

    2011-01-26

    Hydroxypropyl methylcellulose (HPMC) is a substituted cellulose that reduces serum cholesterol at modest intake levels. HPMC has also been used for decades in gluten-free breads at a level to optimize loaf volume. Because consumers resist the consumption of whole wheat breads, the sensory and physical properties of all oat and barley breads incorporating HPMC were evaluated. Oat and barley also contain β-glucan, a glucose polymer similar to HPMC that also lowers cholesterol. The textural and sensory properties of the breads were determined by instrumental and chemical methods and sensory panels. HPMC increased the loaf volume of the breads by up to 2 times and decreased hardness immediately after baking and after up to 3 days of storage. Barley bread with HPMC was rated the highest in overall acceptability by sensory panelists compared to oat and wheat breads with or without HPMC. PMID:21189014

  5. Correlation between the permeability of metoprolol tartrate through plasticized isolated ethylcellulose/hydroxypropyl methylcellulose films and drug release from reservoir pellets.

    PubMed

    Ye, Zhi-wei; Rombout, Patrick; Remon, Jean Paul; Vervaet, Chris; Van den Mooter, Guy

    2007-09-01

    The present study investigates if drug diffusion through plasticized isolated ethylcellulose (EC)/hydroxypropyl methylcellulose (HPMC) films prepared by solvent casting can be used as a tool to develop spray-coated dosage forms. In particular, the importance of the level and type of plasticizers was investigated. The permeability of the model drug metoprolol tartrate through plasticized isolated films could be adjusted by selecting the type and amount of plasticizer in the films due to the different hydrophilicity of the plasticizers. The release of metoprolol tartrate from coated pellets is consistent with the drug diffusion through the films made up of the same polymer blends. This indicated that it is useful to test isolated films for early predictions and for formulation optimization. PMID:17383166

  6. Improvement of the mechanical and barrier properties of methylcellulose-based films by treatment with HEMA and silane monomers under gamma radiation

    NASA Astrophysics Data System (ADS)

    Khan, Ruhul A.; Dussault, Dominic; Salmieri, Stephane; Safrany, Agnes; Lacroix, Monique

    2012-08-01

    Methylcellulose (MC)-based films were prepared by casting from its 1% aqueous solution containing 0.5% vegetable oil, 0.25% glycerol and 0.025% Tween®-80. Puncture strength (PS), puncture deformation (PD) and water vapor permeability (WVP) of the films were found to be 147 N/mm, 3.46 mm, and 6.34 g mm/m2 day kPa, respectively. The monomer, 2-hydroxyethyl methacrylate (HEMA) (0.1-1%, w/w) was incorporated into the MC-based solution and films were prepared by casting. Films were then exposed to gamma radiation (5-25 kGy) and it revealed that 1% HEMA containing films showed the highest PS values (282 N/mm at 10 kGy). Silane monomer (3-aminopropyl tri-ethoxy silane) (0.1-1%, w/w) was also added into the MC-based films and were found to improve the strength of the films significantly. In comparison between HEMA and silane treatment onto MC-based films, it was observed that silane performed better strength and barrier properties. Surface morphology of the monomer treated films was examined by scanning electron microscopy and suggested better appearance than MC-based film.

  7. Effect of plasticizer type and amount on hydroxypropyl methylcellulose-beeswax edible film properties and postharvest quality of coated plums (cv. Angeleno).

    PubMed

    Navarro-Tarazaga, Maria Ll; Sothornvit, Rungsinee; Pérez-Gago, María B

    2008-10-22

    The effect of the composition of hydroxypropyl methylcellulose (HPMC)-beeswax (BW) edible coatings on stand-alone film properties and on postharvest quality of coated 'Angeleno' plums was studied. Glycerol (G) and mannitol (M) were tested as plasticizers at two different plasticizer/HPMC ratios (100:1 and 300:1 molar basis). BW content was 20 or 40% (dry basis). An increase in G content increased film flexibility and vapor permeability (WVP), whereas an increase in M content enhanced film brittleness without affecting WVP. An increase in BW content reduced film flexibility and reduced WVP of only G-plasticized films. Coatings reduced plum softening and bleeding, but were not effective in reducing plum weight loss. At low plasticizer content, coatings reduced texture loss effectively. Low BW also lowered plum bleeding. Plasticizer type affected only ethanol and acetaldehyde contents without affecting the remaining quality parameters. Therefore, HPMC-BW coatings have the potential to extend the shelf life of plums. However, this effect depends on coating composition. Differences between coating and film performance indicate that data from stand-alone films may be used as a preliminary screening, but coating performance should be analyzed on coated fruit. PMID:18823125

  8. Inhibition of Penicillium digitatum and Penicillium italicum by hydroxypropyl methylcellulose-lipid edible composite films containing food additives with antifungal properties.

    PubMed

    Valencia-Chamorro, Silvia A; Palou, Lluís; del Río, Miguel A; Pérez-Gago, María B

    2008-12-10

    New hydroxypropyl methylcellulose (HPMC)-lipid edible composite films containing low-toxicity chemicals with antifungal properties were developed. Tested chemicals were mainly salts of organic acids, salts of parabens, and mineral salts, classified as food additives or generally recognized as safe (GRAS) compounds. Selected films containing food preservatives were used for in vitro evaluation (disk diameter test) of their antifungal activity against Penicillium digitatum (PD) and Penicillium italicum (PI), the most important postharvest pathogens of fresh citrus fruit. Mechanical properties and oxygen (OP) and water vapor permeabilities (WVP) of selected films were also determined. Film disks containing parabens and their mixtures inhibited PD and PI to a higher extent than the other chemicals tested. Among all organic acid salts tested, potassium sorbate (PS) and sodium benzoate (SB) were the most effective salts in controlling both PD and PI. The use of mixtures of parabens or organic acid salts did not provide an additive or synergistic effect for mold inhibition when compared to the use of single chemicals. Barrier and mechanical properties of films were affected by the addition of food preservatives. Results showed that HPMC-lipid films containing an appropriate food additive should promise as potential commercial antifungal edible coatings for fresh citrus fruit. PMID:19012404

  9. Effect of antifungal hydroxypropyl methylcellulose-lipid edible composite coatings on Penicillium decay development and postharvest quality of cold-stored "Ortanique" mandarins.

    PubMed

    Valencia-Chamorro, Silvia A; Pérez-Gago, María B; Del Río, Miguel A; Palou, Lluís

    2010-10-01

    Edible composite coatings based on hydroxypropyl methylcellulose (HPMC), hydrophobic components (beeswax and shellac), and food preservatives with antifungal properties were evaluated on "Ortanique" mandarins during long-term cold storage. Selected food preservatives included potassium sorbate (PS), sodium benzoate (SB), sodium propionate (SP), and their mixtures. Intact mandarins or mandarins artificially inoculated with the pathogens Penicillium digitatum and Penicillium italicum, the causal agents of citrus postharvest green (GM) and blue (BM) molds, respectively, were coated and stored up to 8 wk at 5 °C + 1 wk of shelf-life at 20 °C. HPMC-lipid coatings containing food preservatives controlled better GM than BM on Ortanique mandarins. SB- and SB + SP-based coatings reduced the incidence of GM by about 35% after 4 wk at 5 °C. Among all coatings, only the SB-based coating reduced the incidence of GM (about 16%) after 6 wk at 5 °C. All coatings significantly reduced disease severity of both GM and BM after 6 wk at 5 °C. Analytical and sensory fruit quality was evaluated on intact mandarins. All coatings, especially the SB + SP-based coatings, were effective to control weight loss and maintain the firmness of coated mandarins. Internal gas concentration, juice ethanol and acetaldehyde content, sensory flavor, off-flavor, and fruit appearance were not adversely affected by the application of the antifungal coatings. Further studies should focus on the modification of some physical characteristics of the coatings to improve the gloss and visual aspect of treated mandarins. PMID:21535515

  10. SYNTHESIS AND IN VITRO CHARACTERIZATION OF HYDROXYPROPYL METHYLCELLULOSE-GRAFT-POLY (ACRYLIC ACID/2-ACRYLAMIDO-2-METHYL-1-PROPANESULFONIC ACID) POLYMERIC NETWORK FOR CONTROLLED RELEASE OF CAPTOPRIL.

    PubMed

    Furqan Muhammad, Iqbal; Mahmood, Ahmad; Aysha, Rashid

    2016-01-01

    A super-absorbent hydrogel was developed by crosslinking of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and acrylic acid with hydroxypropyl methylcellulose (HPMC) for controlled release drug delivery of captopril, a well known antihypertensive drug. Acrylic acid and AMPS were polymerized and crosslinked with HPMC by free radical polymerization, a widely used chemical crosslinking method. N,N'-methylenebisacrylamide (MBA) and potassium persulfate (KPS) were added as cross-linker and initiator, respectively. The hydrogel formulation was loaded with captopril (as model drug). The concentration of captopril was monitored at 205 nm using UV spectrophotometer. Equilibrium swelling ratio was determined at pH 2, 4.5 and 7.4 to evaluate the pH responsiveness of the formed hydrogel. The super-absorbent hydrogels were evaluated by FTIR, SEM, XRD, and thermal analysis (DSC and TGA). The formation of new copolymeric network was determined by FTIR, XRD, TGA and DSC analysis. The hydrogel formulations with acrylic acid and AMPS ratio of 4: 1 and lower amounts of crosslinker had shown maximum swelling. Moreover, higher release rate of captopril was observed at pH 7.4 than at pH 2, because of more swelling capacity of copolymer with increasing pH of the aqueous medium. The present research work confirms the development of a stable hydrogel comprising of HPMC with acrylic acid and AMPS. The prepared hydrogels exhibited pH sensitive behav-ior. This superabsorbent composite prepared could be a successful drug carrier for treating hypertension. PMID:27008813

  11. Evaluating food additives as antifungal agents against Monilinia fructicola in vitro and in hydroxypropyl methylcellulose-lipid composite edible coatings for plums.

    PubMed

    Karaca, Hakan; Pérez-Gago, María B; Taberner, Verònica; Palou, Lluís

    2014-06-01

    Common food preservative agents were evaluated in in vitro tests for their antifungal activity against Monilinia fructicola, the most economically important pathogen causing postharvest disease of stone fruits. Radial mycelial growth was measured in Petri dishes of PDA amended with three different concentrations of the agents (0.01-0.2%, v/v) after 7 days of incubation at 25 °C. Thirteen out of fifteen agents tested completely inhibited the radial growth of the fungus at various concentrations. Among them, ammonium carbonate, ammonium bicarbonate and sodium bicarbonate were the most effective while sodium acetate and sodium formate were the least effective. The effective agents and concentrations were tested as ingredients of hydroxypropyl methylcellulose (HPMC)-lipid edible coatings against brown rot disease on plums previously inoculated with M. fructicola (curative activity). 'Friar' and 'Larry Ann' plums were inoculated with the pathogen, coated with stable edible coatings about 24h later, and incubated at 20 °C and 90% RH. Disease incidence (%) and severity (lesion diameter) were determined after 4, 6, and 8 days of incubation and the 'area under the disease progress stairs' (AUDPS) was calculated. Coatings containing bicarbonates and parabens significantly reduced brown rot incidence in plums, but potassium sorbate, used at 1.0% in the coating formulation, was the most effective agent with a reduction rate of 28.6%. All the tested coatings reduced disease severity to some extent, but coatings containing 0.1% sodium methylparaben or sodium ethylparaben or 0.2% ammonium carbonate or ammonium bicarbonate were superior to the rest, with reduction rates of 45-50%. Overall, the results showed that most of the agents tested in this study had significant antimicrobial activity against M. fructicola and the application of selected antifungal edible coatings is a promising alternative for the control of postharvest brown rot in plums. PMID:24742996

  12. Influence of Hydroxypropyl Methylcellulose on Metronidazole Crystallinity in Spray-Congealed Polyethylene Glycol Microparticles and Its Impact with Various Additives on Metronidazole Release.

    PubMed

    Oh, Ching Mien; Heng, Paul Wan Sia; Chan, Lai Wah

    2015-12-01

    The purpose of this study was to investigate the effect of a hydrophilic polymer, hydroxypropyl methylcellulose (HPMC), on the crystallinity and drug release of metronidazole (MNZ) in spray-congealed polyethylene glycol (PEG) microparticles and to further modify the drug release using other additives in the formulation. HPMC has been used in many pharmaceutical formulations and processes but to date, it has not been employed as an additive in spray congealing. Crystallinity of a drug is especially important to the development of pharmaceutical products as active pharmaceutical ingredients (APIs) are mostly crystalline in nature. A combination of X-ray diffractometry, differential scanning calorimetry, Raman spectroscopy and Fourier transform-infrared spectroscopy (FT-IR) spectroscopy was employed to investigate the degree of crystallinity and possible solid-state structure of MNZ in the microparticles. The microparticles with HPMC were generally spherical. Spray congealing decreased MNZ crystallinity, and the presence of HPMC reduced the drug crystallinity further. The reduction in MNZ crystallinity was dependent on the concentration of HPMC. Smaller HPMC particles also resulted in a greater percentage reduction in MNZ crystallinity. Appreciable modification to MNZ release could be obtained with HPMC. However, this was largely attributed to the role of HPMC in forming a diffusion barrier. Further modification of drug release from spray-congealed PEG-HPMC microparticles was achieved with the addition of 5% w/w dicalcium phosphate but not with magnesium stearate, methyl cellulose, polyvinylpyrrolidone, silicon dioxide and sodium oleate/citric acid. Dicalcium phosphate facilitated formation of the diffusion barrier. PMID:25933626

  13. Preparation and characterization of gatifloxacin-loaded sodium alginate hydrogel membranes supplemented with hydroxypropyl methylcellulose and hydroxypropyl cellulose polymers for wound dressing

    PubMed Central

    Prabu, Durai; Majdalawieh, Amin F.; Abu-Yousef, Imad A.; Inbasekaran, Kadambari; Balasubramaniam, Tharani; Nallaperumal, Narayanan; Gunasekar, Conjeevaram J.

    2016-01-01

    Introduction: The aim of this study is to evaluate gatifloxacin-loaded sodium alginate hydrogel membranes, supplemented with glycerol (a plasticizer), glutaraldehyde (a cross-linking agent), and hydroxypropyl methylcellulose (HPMC) or hydroxypropyl cellulose (HPC) polymers, as potential wound dressing materials based on their physicochemical properties and the sustain-release phenomenon. Materials and Methods: The physicochemical properties of the prepared hydrogel membranes were evaluated by several methods including Fourier transform infrared and differential scanning calorimetry. Different techniques were used to assess the swelling behavior, tensile strength and elongation, % moisture absorption, % moisture loss, water vapor transmission rate (WVTR), and microbial penetration for the hydrogel membranes. In vitro gatifloxacin release from the hydrogel membranes was examined using the United States Pharmacopeia XXIII dissolution apparatus. Four kinetics models (zero-order, first-order, Higuchi equation, and Korsmeyer-Peppas equation) were applied to study drug release kinetics. Results: The addition of glycerol, glutaraldehyde, HPMC, and HPC polymers resulted in a considerable increase in the tensile strength and flexibility/elasticity of the hydrogel membranes. WVTR results suggest that hydrated hydrogel membranes can facilitate water vapor transfer. None of the hydrogel membranes supported microbial growth. HPMC-treated and HPC-treated hydrogel membranes allow slow, but sustained, release of gatifloxacin for 48 h. Drug release kinetics revealed that both diffusion and dissolution play an important role in gatifloxacin release. Conclusions: Given their physicochemical properties and gatifloxacin release pattern, HPMC-treated and HPC-treated hydrogel membranes exhibit effective and sustained drug release. Furthermore, HPMC-treated and HPC-treated hydrogel membranes possess physiochemical properties that make them effective and safe wound dressing materials. PMID

  14. Spatio-temporal morphology changes in and quenching effects on the 2D spreading dynamics of cell colonies in both plain and methylcellulose-containing culture media.

    PubMed

    Muzzio, N E; Pasquale, M A; Huergo, M A C; Bolzán, A E; González, P H; Arvia, A J

    2016-06-01

    To deal with complex systems, microscopic and global approaches become of particular interest. Our previous results from the dynamics of large cell colonies indicated that their 2D front roughness dynamics is compatible with the standard Kardar-Parisi-Zhang (KPZ) or the quenched KPZ equations either in plain or methylcellulose (MC)-containing gel culture media, respectively. In both cases, the influence of a non-uniform distribution of the colony constituents was significant. These results encouraged us to investigate the overall dynamics of those systems considering the morphology and size, the duplication rate, and the motility of single cells. For this purpose, colonies with different cell populations (N) exhibiting quasi-circular and quasi-linear growth fronts in plain and MC-containing culture media are investigated. For small N, the average radial front velocity and its change with time depend on MC concentration. MC in the medium interferes with cell mitosis, contributes to the local enlargement of cells, and increases the distribution of spatio-temporal cell density heterogeneities. Colony spreading in MC-containing media proceeds under two main quenching effects, I and II; the former mainly depending on the culture medium composition and structure and the latter caused by the distribution of enlarged local cell domains. For large N, colony spreading occurs at constant velocity. The characteristics of cell motility, assessed by measuring their trajectories and the corresponding velocity field, reflect the effect of enlarged, slow-moving cells and the structure of the medium. Local average cell size distribution and individual cell motility data from plain and MC-containing media are qualitatively consistent with the predictions of both the extended cellular Potts models and the observed transition of the front roughness dynamics from a standard KPZ to a quenched KPZ. In this case, quenching effects I and II cooperate and give rise to the quenched

  15. Management of irritable bowel syndrome in primary care: the results of an exploratory randomised controlled trial of mebeverine, methylcellulose, placebo and a self-management website

    PubMed Central

    2013-01-01

    Background Many patients with IBS suffer on-going symptoms. The evidence base is poor for IBS drugs but they are widely prescribed and advised in Guidelines. Cognitive Behavioural Therapy (CBT) can be helpful, but availability is poor in the NHS. We developed a web-based CBT self-management programme (Regul8) in partnership with patients and trialled it and common IBS medications in an exploratory factorial RCT to test trial procedures and provide information for a larger trial. Methods Patients, 16 to 60 years, with IBS symptoms fulfilling Rome III criteria were recruited via GP practices and randomised to over-encapsulated mebeverine, methylcellulose or placebo for 6 weeks and to 1 of 3 website conditions: Regul8 with a nurse telephone session and email support, Regul8 with minimal email support, or no website. Results 135 patients recruited from 26 GP practices. Mean IBS SSS score 241.9 (sd 87.7), IBS-QOL 64 (sd 20) at baseline. 91% follow-up at 12 weeks. Mean IBS SSS decreased by 35 points from baseline to 12 weeks. There was no significant difference in IBS SSS or IBS-QOL score between medication or website groups at 12 weeks, or in medication groups at 6 weeks, or IBS-QOL in website groups at 6 weeks. However, IBS SSS at 6 weeks was lower in the No website group than the website groups (IBS SSS no website =162.8 (95% CI 137.4-188.3), website 197.0 (172.4 - 221.7), Website + telephone support 208.0 (183.1-233.0) p = 0.037). Enablement and Subjects Global Assessment of relief (SGA) were significantly improved in the Regul8 groups compared to the non-website group at 12 weeks (Enablement = 0 in 56.8% of No website group, 18.4% website, 10.5% Website + support, p = 0.001) (SGA; 32.4% responders in No website group, 45.7% website group, 63.2% website + support group, p = 0.035). Conclusions This exploratory study demonstrates feasibility and high follow-up rates and provides information for a larger trial. Primary outcomes (IBS SS and IBS

  16. Sensitive determination of aspirin and its metabolites in plasma by LC-UV using on-line solid-phase extraction with methylcellulose-immobilized anion-exchange restricted access media.

    PubMed

    Yamamoto, Eiichi; Takakuwa, Susumu; Kato, Takashi; Asakawa, Naoki

    2007-02-01

    We describe a sensitive determination of aspirin (ASA) and its three metabolites (salicylic acid [SA], 2,3-dihydroxybenzoic acid [2,3-DHBA], and 2,5-dihydroxybenzoic acid [gentisic acid (GA)]) in rat plasma. Analysis was carried out by on-line solid-phase extraction (SPE) using a methylcellulose-immobilized-strong anion-exchanger (MC-SAX), followed by liquid chromatography (LC) coupled with UV detection. The lower limits of quantitation for ASA and SA were 60 ng/mL in 100 microL of plasma, respectively. This method was validated with respect to intra- and inter-day precision, accuracy, and linearity up to concentrations of 20,000 ng/mL for ASA, SA, 2,3-DHBA and gentisic acid, respectively. The method was successfully applied to an analysis of the pharmacokinetics of ASA and SA in rats. PMID:16959551

  17. Matrix tablets: the effect of hydroxypropyl methylcellulose/anhydrous dibasic calcium phosphate ratio on the release rate of a water-soluble drug through the gastrointestinal tract I. In vitro tests.

    PubMed

    Mamani, Pseidy L; Ruiz-Caro, Roberto; Veiga, María D

    2012-12-01

    Different hydroxypropyl methylcellulose (HPMC)/anhydrous dibasic calcium phosphate (ADCP) matrix tablets have been developed aiming to evaluate the influence of both components ratio in the control release of a water-soluble drug (theophylline). In order to characterise the matrix tablets, swelling, buoyancy and dissolution studies have been carried out in different aqueous media (demineralised water, progressive pH medium, simulated gastric fluid, simulated intestinal fluid and simulated colonic fluid). The HPMC/ADCP ratio has turned out to be the determinant in the matrix behaviour: the HPMC characteristic swelling behaviour was modulated, in some cases, by the ADCP characteristic acidic dissolution. When the HPMC/ADCP ratio was ≥0.69, buoyancy, continuous swelling and low theophylline dissolution rate from the matrices (H1, H2 and H3) were observed in all dissolution media. Consequently, these formulations could be adequate as gastro-retentive drug delivery systems. Additionally, HPMC/ADCP ratio ≤0.11 (H5 and H6) induces a pH-dependent drug release which could be applied to design control drug release enteric formulations (with a suitable enteric coating). Finally, a HPMC/ADCP ratio between 0.11 and 0.69 (H4) yield a gastrointestinal controlled drug release, due to its time-dependent buoyancy (7 h) and a total drug delivery in 17 h in simulated colonic fluid. PMID:22907778

  18. Evaluation of the film-coating properties of a hydroxyethyl cellulose/hydroxypropyl methylcellulose polymer system.

    PubMed

    Li, Shun Por; Martellucci, Stephen A; Bruce, Richard D; Kinyon, Adam C; Hay, Michael B; Higgins, John D

    2002-04-01

    The effect of different grades of hydroxyethyl cellulose (HEC) and hydroxypropyl methllcellulose (HPMC) on the film-formation and taste-masking ability for ibuprofen granules was evaluated. Three batches of coated ibuprofen granules were prepared using a roto-granulator, each with a different coating composition. Two grades of HEC [MW300,000 (H) and MW90,000 (L)] were combined with three different grades of HPMC [MW 11,000 (L), MW 25,000 (M) and MW 35,000 (H)] to prepare the coating solutions. Mechanical strength and physical properties of the polymer films were evaluated. Films made from HPMC (L)/HEC (H), HPMC (M)/HEC (H), and HPMC (H)/HEC (H) were stronger and more flexible than the HPMC (L) HEC (L) films. The assay, dissolution, particle size distribution, and environmental scanning electron microscopy (ESEM) data of the three batches of the coated ibuprofen granules were similar. PMID:12056532

  19. Preparation and characterization of collagen/hydroxypropyl methylcellulose (HPMC) blend film.

    PubMed

    Ding, Cuicui; Zhang, Min; Li, Guoying

    2015-03-30

    This study aimed to prepare and characterize the collagen/HPMC blend film (1/1). Thermogravimetric analysis and differential scanning calorimetry were used to investigate the thermal properties of the film. Both thermal decomposition temperature and denaturation temperature of the blend film were higher than those of the collagen film due to the intermolecular hydrogen bonding interaction between collagen and HPMC, which was demonstrated by Fourier transform infrared spectroscopy. Additionally, the morphologies, mechanical properties and hydrophilicity of films were examined. The blend film exhibited a more homogeneous and compact structure compared with that of the collagen film, as observed from scanning electron microscopy and atomic force microscopy. The tensile strength, ultimate elongation and hydrophilicity of the blend film were superior to those of the pure collagen film. Furthermore, the introduction of polyethylene glycol 1500 had almost no influence on the thermal properties of the blend film but obviously improved its stretch-ability and smoothness. PMID:25563960

  20. Composite edible films based on hydroxypropyl methylcellulose reinforced with microcrystalline cellulose nanoparticles.

    PubMed

    Bilbao-Sáinz, Cristina; Avena-Bustillos, Roberto J; Wood, Delilah F; Williams, Tina G; McHugh, Tara H

    2010-03-24

    It has been stated that hydroxypropyl methyl cellulose (HPMC) based films have promising applications in the food industry because of their environmental appeal, low cost, flexibility and transparency. Nevertheless, their mechanical and moisture barrier properties should be improved. The aim of this work was to enhance these properties by reinforcing the films with microcrystalline cellulose (MCC) at the nano scale level. Three sizes of MCC nanoparticles were incorporated into HPMC edible films at different concentrations. Identical MCC nanoparticles were lipid coated (LC) prior to casting into HPMC/LC-MCC composite films. The films were examined for mechanical and moisture barrier properties verifying how the addition of cellulose nanoparticles affected the water affinities (water adsorption/desorption isotherms) and the diffusion coefficients. The expected reinforcing effect of the MCC was observed: HPMC/MCC and HPMC/LC-MCC films showed up to 53% and 48% increase, respectively, in tensile strength values in comparison with unfilled HPMC films. Furthermore, addition of unmodified MCC nanoparticles reduced the moisture permeability up to 40% and use of LC-MCC reduced this value up to 50%. Water vapor permeability was mainly influenced by the differences in water solubility of different composite films since, in spite of the increase in water diffusivity values with the incorporation of MCC to HPMC films, better moisture barrier properties were achieved for HPMC/MCC and HPMC/LC-MCC composite films than for HPMC films. PMID:20187652

  1. Properties of starch-hydroxypropyl methylcellulose based films obtained by compression molding.

    PubMed

    Ortega-Toro, Rodrigo; Jiménez, Alberto; Talens, Pau; Chiralt, Amparo

    2014-08-30

    Corn starch-glycerol (1:0.3) films, containing or not citric acid (1g/100g starch) and HPMC (10 and 20g/100g starch), are obtained by compression molding. The microstructure of the films, the thermal behavior, the X-ray diffraction spectra and the physical properties (mechanical, barrier and optical) were analyzed after 1 and 5 storage weeks at 25°C and 53% relative humidity. The bonded citric acid and film solubility were also determined. Starch-HPMC blend films showed a dispersed phase of HPMC in a continuous, starch-rich phase with lower glass transition than HPMC-free films. The addition of citric acid also provoked a decrease in glass transition in line with the partial hydrolysis of starch chains. Both components implied a decrease in the water vapour permeability while the oxygen permeability slightly increased. Although citric acid only provoked a small hardening effect in the films, it greatly decreased their extensibility (weak cross-linking effect), which seems to increase during film storage. Starch crystallization during storage was inhibited by both citric acid and HPMC. PMID:24815412

  2. Physical properties of emulsion-based hydroxypropyl methylcellulose films: effect of their microstructure.

    PubMed

    Zúñiga, R N; Skurtys, O; Osorio, F; Aguilera, J M; Pedreschi, F

    2012-10-01

    The initial characteristics of emulsions and the rearrangement of the oil droplets in the film matrix during film drying, which defines its microstructure, has an important role in the physical properties of the emulsion-based films. The objective of this work was to study the effect of the microstructure (two droplet size distributions) and stability (with or without surfactant) of HPMC oil-in-water emulsions over physical properties of HPMC emulsion-based edible films. HPMC was used to prepare sunflower oil-in-water emulsions containing 0.3 or 1.0% (w/w) of oil with or without SDS, as surfactant, using an ultrasonic homogenizer. Microstructure, rheological properties and stability of emulsions (creaming) were measured. In addition, microstructure, coalescence of oil droplets, surface free energy, optical and mechanical properties and water vapor transfer of HPMC films were evaluated. Image analysis did not show differences among droplet size distributions of emulsions prepared at different oil contents; however, by using SDS the droplet size distributions were shifted to lower values. Volume mean diameters were 3.79 and 3.77 μm for emulsions containing 0.3 and 1.0% without surfactant, respectively, and 2.72 and 2.71 μm for emulsions with SDS. Emulsions formulated with 1.0% of oil presented higher stability, with almost no change during 5 and 3 days of storage, for emulsions with and without SDS, respectively. Internal and surface microstructure of emulsion-based films was influenced by the degree of coalescence and creaming of the oil droplets. No effect of microstructure over the surface free energy of films was found. The incorporation of oil impaired the optical properties of films due to light scattering of light. Addition of oil and SDS decreased the stress at break of the emulsion-based films. The replace of HPMC by oil and SDS produce a lower "amount" of network structure in the films, leading to a weakening of their structure. The oil content and SDS addition had an effect over the microstructure and physical properties of HPMC-based emulsions which lead to different microstructures during film formation. The way that oil droplets were structured into the film had an enormous influence over the physical properties of HPMC films. PMID:22840052

  3. Physical properties of emulsion-based hydroxypropyl methylcellulose/whey protein isolate (HPMC/WPI) edible films.

    PubMed

    Rubilar, Javiera F; Zúñiga, Rommy N; Osorio, Fernando; Pedreschi, Franco

    2015-06-01

    The objective of this research was to study the effect of the film microstructure of oil-in-water emulsions stabilized by hydroxypropyl methyl cellulose/whey protein isolate (HPMC/WPI) with or without sodium dodecyl sulfate (SDS) over physical properties of HPMC/WPI emulsion-based films. The films were prepared with different HPMC/WPI-oil-SDS combinations (%w/w for 100g of dispersion): HPMC; WPI; HPMC/1WPI-0.5-SDS; HPMC/1WPI-1; HPMC/2WPI-0.5; HPMC/2WPI-1-SDS. Physical properties of films were evaluated. The results showed no statistical differences (p>0.05) between the thicknesses of EFs (0.156 ± 0.004 mm). The effect of oil content and incorporation of SDS showed the inverse trend for WI and ΔE, the increasing order of change, for WI and ΔE, among the formulation evaluated was: HPMC/1WPI-1>HPMC/2WPI-0.5>HPMC/2WPI-1.0-SDS≈HPMC/1WPI-0.5-SDS≈WPI>HPMC for WI and HPMC/1WPI-0.5-SDS>HPMC/2WPI-1.0-SDS>HPMC/2WPI-0.5>HPMC/1WPI-1 for ΔE, respectively. The addition of oil and SDS decreased the TS and EB, because oil addition into EF induces the development of structural discontinuities, producing an EF with less chain mobility, and consequently, with less flexibility and resistance to fracture. PMID:25843831

  4. Biopolymeric antimicrobial films: study of the influence of hydroxypropyl methylcellulose, tapioca starch and glycerol contents on physical properties.

    PubMed

    Espinel Villacrés, Ricardo A; Flores, Silvia K; Gerschenson, Lía N

    2014-03-01

    Mixture design methodology was applied to study the effect of different levels of tapioca starch (TS), hydroxypropyl methylcelullose (HPMC), and glycerol (Gly) on the physical properties of biopolymeric films supporting potassium sorbate (KS; 0.3% w/w) with the goal of contributing to the development of materials for preventing food surface contamination. Mechanical properties, water vapour permeability (WVP), solubility in water (S) and colour attributes were evaluated on the films. HPMC addition produced an increase of elastic modulus (Ec), stress at break (σb) and S. It also decreased the yellow index (YI) values and the strain at break (εb). The study was deepened using the formulation containing 2.67 g/100g of TS, 0.67 g/100g of HPMC, 1.67 g/100g Gly and 0.3g/100g KS, observing that it behaved as an effective antimicrobial barrier against Zygosaccharomyces bailii external contamination. Microstructural analysis allowed us to conclude that HPMC incorporation to a TS network decreased roughness of the films and it also increased permeability to oxygen (PO2). PMID:24433893

  5. Hydroxypropyl methylcellulose mediated precipitation inhibition of sirolimus: from a screening campaign to a proof-of-concept human study.

    PubMed

    Petruševska, Marija; Homar, Miha; Petek, Boštjan; Resman, Aleksander; Kocjan, Darko; Urleb, Uroš; Peternel, Luka

    2013-06-01

    The aim of this study was to develop a sirolimus (BCS class II drug substance) solid oral dosage form containing a precipitation inhibitor, which would result in an improved sirolimus absorption in humans compared to the formulation containing nanosized sirolimus without a precipitation inhibitor, i.e., Rapamune. The selection of the precipitation inhibitor was based on the results of a screening campaign that identified two "hit" excipients: HPMC 603 (i.e., Pharmacoat 603) and Poloxamer 407. However, in a confirmatory precipitation inhibitor study using biorelevant media (Fa/FeSSIF) HPMC 603 more effectively inhibited sirolimus precipitation than Poloxamer 407. In the PAMPA assay, HPMC 603, but not Poloxamer 407, significantly increased the flux of the sirolimus across the membrane lipid layer. Additionally, a differential scanning calorimetry (DSC) and an infrared (IR) spectroscopy study revealed that interactions between the sirolimus and HPMC 603 were developed that could lead to the observed precipitation inhibition effect. Based on the above data, two formulations with HPMC 603-coated sirolimus particles were developed, namely, formulation A (d (0.5) = 0.21 μm) and formulation B (d (0.5) = 1.7 μm). A human pharmacokinetic study outlined that significantly higher AUC and Cmax were obtained for formulations A and B in comparison to Rapamune. This result could be attributed to the HPMC 603 (Pharmacoat 603) mediated sirolimus precipitation inhibition resulting in improved sirolimus absorption from the gastrointestinal tract in humans. PMID:23586335

  6. Controlled release of dual drug-loaded hydroxypropyl methylcellulose matrix tablet using drug-containing polymeric coatings.

    PubMed

    Lee, B J; Ryu, S G; Cui, J H

    1999-10-15

    A dual drug-loaded hydroxypropylmethylcellulose (HPMC) matrix tablet simultaneously containing drug in inner tablet core and outer coated layer was formulated using drug-containing aqueous-based polymeric Eudragit RS30D dispersions. Effects of coating levels, drug loadings in outer layers, amount and type of five plasticizers and talc concentration on the release characteristics were evaluated on the characteristics in simulated gastric fluid for 2 h followed by a study in intestinal fluids. Melatonin (MT) was selected as a model drug. The surface morphology of dual drug-loaded HPMC tablets using scanning electron microscope (SEM) was smooth, showing the distinct coated layer with about 75-microm coating thickness at the 15% coating level. Unlike the uncoated and conventionally coated HPMC tablet, the dual drug-loaded HPMC matrix tablet gave a biphasic linear release, showing a zero-order for 4 h (first) followed by another zero-order release when fitted using linear regression (r(2) = 0.99). As the coating levels (15, 25%) increased, the release rate was further decreased. The biphasic release profiles of dual drug-loaded HPMC matrix tablet was unchanged except when 25% coating level containing 0.5% drug concentration was applied. As the drug concentration in polymeric coating dispersion increased (0.25-1.0%), the amount of drug released increased. The time for the first linear release was also advanced. However, the biphasic release pattern was not changed. The biphasic release profiles of dual drug-loaded HPMC matrix tablet were highly modified, depending on the amount and type of five plasticizers. Talc (10-30%) in coating dispersion as an anti-sticking material did not affect the release profiles. The current dual drug-loaded HPMC matrix tablet, showing biphasic release profiles may provide an alternative to deliver drugs with circadian rhythmic behaviors in the body but needs to be further validated in future in human studies. The dual drug-loaded coating method is also interesting for the modified release of poorly water-soluble drugs because solubilizers and other additives can be added in drug-containing polymeric coating dispersions. PMID:10528084

  7. STUDYING THE IMPACT OF FORMULATION AND PROCESSING PARAMETERS ON THE RELEASE CHARACTERISTICS FROM HYDROXYPROPYL METHYLCELLULOSE MATRIX TABLETS OF DICLOFENAC.

    PubMed

    Elzayat, Ehab M; Abdel-Rahman, Ali A; Ahmed, Sayed M; Alanazi, Fars K; Habib, Walid A; Sakr, Adel

    2016-01-01

    Hydrophilic matrices, especially HPMC based, are widely used to provide sustained delivery where drug release occurs mainly by diffusion. A 3(2) full factorial design was used to develop and evaluate HPMC matrix tablet for sustained delivery of diclofenac. The influences of polymer concentration/viscosity, diluent type/ratio, drug load/solubility, compression force and pH change on drug release were investigated. Ten tablet formulations were prepared using wet granulation. HPMC K15M (10-30% w/w) was used as the polymer forming matrix. The release kinetics, compatibility studies, lot reproducibility and effect on storage were discussed. Increasing polymer concentration and compression force showed antagonistic effect on release rate. Mannitol tends to increase release rate more than lactose. Reversing diluent ratio between lactose and MCC did not affect drug release. Changing pH resulted in burst release whereas drug solubility is pH independent. F1 showed similar release to Voltaren SR and followed Higuchi model. Drug and polymer were compatible to each other. The formulation is stable at long and intermediate conditions with a significant increase in release rate at accelerated conditions due to water uptake and polymer swelling. The developed formulation was successful for a sustained delivery of diclofenac. PMID:27180437

  8. 21 CFR 201.319 - Water-soluble gums, hydrophilic gums, and hydrophilic mucilloids (including, but not limited to...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... gum, kelp, methylcellulose, plantago seed (psyllium), polycarbophil tragacanth, and xanthan gum) as... gum, kelp, methylcellulose, plantago seed (psyllium), polycarbophil tragacanth, and xanthan gum) as..., methylcellulose, plantago seed (psyllium), polycarbophil, tragacanth, and xanthan gum. Esophageal obstruction...

  9. 21 CFR 201.319 - Water-soluble gums, hydrophilic gums, and hydrophilic mucilloids (including, but not limited to...

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... gum, kelp, methylcellulose, plantago seed (psyllium), polycarbophil tragacanth, and xanthan gum) as... gum, kelp, methylcellulose, plantago seed (psyllium), polycarbophil tragacanth, and xanthan gum) as..., methylcellulose, plantago seed (psyllium), polycarbophil, tragacanth, and xanthan gum. Esophageal obstruction...

  10. The suitability of tris(hydroxylmethyl) aminomethane (THAM) as a buffering system for hydroxypropyl methylcellulose (HPMC) hydrophilic matrices containing a weak acid drug.

    PubMed

    Pygall, Samuel R; Kujawinski, Sarah; Timmins, Peter; Melia, Colin D

    2010-03-15

    There are few studies of alkalising pH-modifiers in HPMC hydrophilic matrices. These agents may be incorporated to provide microenvironmental buffering and facilitate pH-independent release of weak acid drugs. This study compared tris(hydroxylmethyl) aminomethane (THAM, TRIS, tromethamine, trometamol) with sodium citrate as internal buffering agents for HPMC (4000 cps) 2208 and 2910 matrices containing felbinac, a weak acid drug which exhibits pH-dependent solubility. Drug release at pH 1.2 and 7.5 was accelerated by both buffers, but THAM-buffered matrices provided extended, diffusion-based release kinetics, without loss of matrix integrity at high buffer concentrations. Release kinetics appeared to be independent of media pH. THAM did not depress the sol-gel transition temperature or suppress HPMC particle swelling, and had minimal effects on gel layer formation. Sodium citrate promoted greater thickness of the early gel layer than THAM. Measurements of internal gel layer pH showed that both buffers produced a rapid alkalisation of the gel layer which was progressively lost. As result of its higher pK(a) and molar ratio on a percent weight basis, THAM provided a higher internal pH and a greater longevity of pH modification. It is concluded that THAM offers a useful buffering option for weak acid drugs in HPMC-based systems. PMID:20005935

  11. Formulation and in vitro evaluation of floating tablets of hydroxypropyl methylcellulose and polyethylene oxide using ranitidine hydrochloride as a model drug

    PubMed Central

    Gharti, KP; Thapa, P; Budhathoki, U; Bhargava, A

    2012-01-01

    The present study was carried out with an objective of preparation and in vitro evaluation of floating tablets of hydroxypropyl methyl cellulose (HPMC) and polyethylene oxide (PEO) using ranitidine hydrochloride as a model drug. The floating tablets were based on effervescent approach using sodium bicarbonate a gas generating agent. The tablets were prepared by dry granulation method. The effect of polymers concentration and viscosity grades of HPMC on drug release profile was evaluated. The effect of sodium bicarbonate and stearic acid on drug release profile and floating properties were also investigated. The result of in vitro dissolution study showed that the drug release profile could be sustained by increasing the concentration of HPMC K15MCR and Polyox WSR303. The formulation containing HPMC K15MCR and Polyox WSR303 at the concentration of 13.88% showed 91.2% drug release at the end of 24 hours. Changing the viscosity grade of HPMC from K15MCR to K100MCR had no significant effect on drug release profile. Sodium bicarbonate and stearic acid in combination showed no significant effect on drug release profile. The formulations containing sodium bicarbonate 20 mg per tablet showed desired buoyancy (floating lag time of about 2 minutes and total floating time of >24 hours). The present study shows that polymers like HPMC K15MCR and Polyox WSR303 in combination with sodium bicarbonate as a gas generating agent can be used to develop sustained release floating tablets of ranitidine hydrochloride. PMID:23493037

  12. Formulation and in vitro evaluation of floating tablets of hydroxypropyl methylcellulose and polyethylene oxide using ranitidine hydrochloride as a model drug.

    PubMed

    Gharti, Kp; Thapa, P; Budhathoki, U; Bhargava, A

    2012-10-01

    The present study was carried out with an objective of preparation and in vitro evaluation of floating tablets of hydroxypropyl methyl cellulose (HPMC) and polyethylene oxide (PEO) using ranitidine hydrochloride as a model drug. The floating tablets were based on effervescent approach using sodium bicarbonate a gas generating agent. The tablets were prepared by dry granulation method. The effect of polymers concentration and viscosity grades of HPMC on drug release profile was evaluated. The effect of sodium bicarbonate and stearic acid on drug release profile and floating properties were also investigated. The result of in vitro dissolution study showed that the drug release profile could be sustained by increasing the concentration of HPMC K15MCR and Polyox WSR303. The formulation containing HPMC K15MCR and Polyox WSR303 at the concentration of 13.88% showed 91.2% drug release at the end of 24 hours. Changing the viscosity grade of HPMC from K15MCR to K100MCR had no significant effect on drug release profile. Sodium bicarbonate and stearic acid in combination showed no significant effect on drug release profile. The formulations containing sodium bicarbonate 20 mg per tablet showed desired buoyancy (floating lag time of about 2 minutes and total floating time of >24 hours). The present study shows that polymers like HPMC K15MCR and Polyox WSR303 in combination with sodium bicarbonate as a gas generating agent can be used to develop sustained release floating tablets of ranitidine hydrochloride. PMID:23493037

  13. Effect of thermal gelation on dissolution from coated tablets.

    PubMed

    Schwartz, J B; Alvino, T P

    1976-04-01

    Tablets with a methylcellulose coating were found to exhibit lower dissolution profiles than those coated with a hydroxypropyl methylcellulose coating at 37 degrees, and the cause was investigated. The differences are attributed to thermal gelation of the methylcellulose at temperatures near 37 degrees, which creates a barrier to the dissolution process and essentially changes the dissolution mechanism. This mechanism is substantiated by the fact that at temperatures below the gel point and at increased agitation, the effect disappears. The retarded dissolution effect is not peculiar to the drug involved. PMID:1271258

  14. Analysis of the permeation and mechanical characteristics of some aqueous-based film coating systems.

    PubMed

    Okhamafe, A O; York, P

    1983-07-01

    The moisture permeability and mechanical properties of some aqueous-based free films have been evaluated using sorption-desorption and stress-strain techniques, respectively. These properties for blends of two film-formers--hydroxypropyl methylcellulose and polyvinyl alcohol--have been compared with those of hydroxypropyl methylcellulose films plasticized with polyethylene glycols. The polyethylene glycols generally increased the moisture permeability of hydroxypropyl methylcellulose films while polyvinyl alcohol decreased it. Both polyvinyl alcohol and the polyethylene glycols lowered tensile strength at break and Young's modulus but the effects of the polyethylene glycols were more pronounced. These results are discussed in terms of structural interactions between film components. All film systems evaluated, except that containing hydroxypropyl methylcellulose alone, exhibited a degree of anisotropy, a phenomenon with potentially adverse consequences in tablet film coating. PMID:6136580

  15. Improved assay for quantitating adherence of ruminal bacteria to cellulose.

    PubMed Central

    Rasmussen, M A; White, B A; Hespell, R B

    1989-01-01

    A quantitative technique suitable for the determination of adherence of ruminal bacteria to cellulose was developed. This technique employs adherence of cells to cellulose disks and alleviates the problem of nonspecific cell entrapment within cellulose particles. By using this technique, it was demonstrated that the adherence of Ruminococcus flavefaciens FD1 to cellulose was inhibited by formaldehyde, methylcellulose, and carboxymethyl cellulose. Adherence was unaffected by acid hydrolysates of methylcellulose, glucose, and cellobiose. PMID:2782879

  16. Development and In vitro Evaluation of Mucoadhesive Buccal Films of Nebivolol

    PubMed Central

    Mane, P. P.; Bushetti, S. S.; Keshavshetti, G. G.

    2014-01-01

    Nebivolol, a cardioselective β-blocker undergoes extensive metabolism in the liver after its oral administration resulting in low bioavailability. Oral administration of nebivolol also causes gastrointestinal disturbances characterised by stomach ache. To overcome these short comings, mucoadhesive buccal films of nebivolol were prepared using different concentrations of hydroxypropyl methylcellulose and hydroxyl ethylcellulose in the ratios of 2:1, 4:1 and 6:1 and hydroxypropyl methylcellulose and methylcellulose in the ratio of 2:2, 4:3 and 6:4 by solvent casting technique. All the prepared films were found to be smooth, elegant and uniform in thickness and weight. Among the three polymer combinations used, 6:4 (BFN6) showed increased in vitro residence time, which appeared to be mainly due to mucoadhesive nature of hydroxylpropyl methylcellulose and methylcellulose. Evaluation of the films showed uniform dispersion of the drug throughout the formulation (96.21±0.71 to 97.02±0.12%). In vitro drug release studies showed better results at the end of 8 h. The release profile of all the formulations was subjected to kinetic analyses, which suggested that the drug was released by diffusion mechanism following super case-II transport. PMID:24843191

  17. Effect of various polymers concentrations on physicochemical properties of floating microspheres.

    PubMed

    Jagtap, Y M; Bhujbal, R K; Ranade, A N; Ranpise, N S

    2012-11-01

    Floating microspheres have emerged as a potential candidate for gastroretentive drug delivery system. For developing a desired intragastric floatation system employing these microspheres, it is necessary to select an appropriate balance between buoyancy and drug releasing rate. These properties mainly depend on the polymers used in the formulation of the microspheres. Hence it is necessory to study the effect of these polymer concentrations on the various physicochemical properties of the microspheres. Floating microspheres were prepared by emulsion solvent evaporation technique utilising different polymers such as ethyl cellulose, Eudragit(®) RS and Eudragit(®) RL by dissolving them in a mixture of dichloromethane and methanol. Release modifiers studied were hydroxypropyl methylcellulose K4M, hydroxypropyl methylcellulose E50 LV and Eudragit(®) EPO. Prepared microspheres were analysed for particle size, surface morphology, entrapment efficiency, buoyancy, differential scanning calorimetry and in-vitro drug release. Ethyl cellulose and Eudragit(®) EPO resulted microspheres with high percentage yield, excellent spherical shape but had very less buoyancies with a high cumulative drug release. Ethyl cellulose microspheres prepared using hydroxypropyl methylcellulose K4M showed more sustained drug release and high buoyancies than that of the microspheres formulated with the hydroxypropyl methylcellulose E50 LV. Amongst these hydroxypropyl methylcellulose E50 LV showed good balance between buoyancy and the drug release. PMID:23798776

  18. A new use of K-Y jelly as a gonioscopy fluid.

    PubMed

    Mehta, H K

    1984-10-01

    Methylcellulose drops varying in strength between 0.3% and 2.0% and isotonic saline are the fluids currently used for gonioscopy and posterior segment examination of the eye with diagnostic contact lenses. The author reports the use of K-Y jelly for such examinations in over 80 patients after having it used on his own eyes without any immediate or delayed ill effects. No observable difference was found between saline drops, methylcellulose drops of 0.3% and 2.0%, and K-Y jelly as regards the visibility of the anterior and posterior segments of the eyes. The more viscous fluids of 2% methylcellulose and K-Y jelly were more convenient to use, as they rarely allowed interposition of air bubbles between the cornea and the contact lens. K-Y jelly was well tolerated by all subjects. PMID:6477858

  19. Conductivity study and fourier transform infrared (FTIR) characterization of methyl cellulose solid polymer electrolyte with sodium iodide conducting ion

    SciTech Connect

    Abiddin, Jamal Farghali Bin Zainal; Ahmad, Azizah Hanom

    2015-08-28

    Sodium ion (Na{sup +}) based solid polymer electrolyte (SPE) has been prepared using solution cast technique with distilled water as solvent and Methylcellulose (MC) as a polymer host. Methylcellulose polymer was chosen as the polymer host due to the abundance of lone pair electrons in the carbonyl and C-O-C constituents, which in turn provide multiple hopping sites for the Na{sup +} conducting ions. Variable compositions of sodium iodide (NaI) salt were prepared to investigate the optimum MC-NaI weight ratio. Results from Electrical Impedance Spectroscopy (EIS) technique show that pure methylcellulose has a low conductivity of 3.61 × 10{sup −11} S/cm.The conductivity increases as NaI content increases up to optimum NaIcomposition of 40 wt%, which yields an average conductivity of 2.70 × 10{sup −5} S/cm.

  20. Effect of different dispersants in compressive strength of carbon fiber cementitious composites

    NASA Astrophysics Data System (ADS)

    Lestari, Yulinda; Bahri, Saiful; Sugiarti, Eni; Ramadhan, Gilang; Akbar, Ari Yustisia; Martides, Erie; Khaerudini, Deni S.

    2013-09-01

    Carbon Fiber Cementitious Composites (CFCC) is one of the most important materials in smart concrete applications. CFCC should be able to have the piezoresistivity properties where its resistivity changes when there is applied a stress/strain. It must also have the compressive strength qualification. One of the important additives in carbon fiber cementitious composites is dispersant. Dispersion of carbon fiber is one of the key problems in fabricating piezoresistive carbon fiber cementitious composites. In this research, the uses of dispersants are methylcellulose, mixture of defoamer and methylcellulose and superplasticizer based polycarboxylate. The preparation of composite samples is similar as in the mortar technique according to the ASTM C 109/109M standard. The additives material are PAN type carbon fibers, methylcellulose, defoamer and superplasticizer (as water reducer and dispersant). The experimental testing conducts the compressive strength and resistivity at various curing time, i.e. 3, 7 and 28 days. The results obtained that the highest compressive strength value in is for the mortar using superplasticizer based polycarboxylate dispersant. This also shown that the distribution of carbon fiber with superplasticizer is more effective, since not reacting with the cementitious material which was different from the methylcellulose that creates the cement hydration reaction. The research also found that the CFCC require the proper water cement ratio otherwise the compressive strength becomes lower.

  1. Factors affecting quality of batter-based gluten-free bread

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While wheat bread has been extensively studied, the quality basis for gluten-free bread remains controversial. Common gluten-free breads are prepared from soft batters, and in such systems, intact and damaged starch, pentosans, added hydrocolloids like xanthan gum and hydroxypropyl methylcellulose (...

  2. Removal of surface lipids improves the functionality of commercial zein in viscoelastic zein-starch dough for gluten-free breadmaking

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize prolamin (zein), together with starch, hydroxypropyl methylcellulose, sugar, salt, yeast and water can form wheat-like cohesive, extensible, viscoelastic dough when mixed above room temperature (e.g. 40 °C). This dough is capable of holding gas. However, it is excessively extensible, and when ...

  3. Formulation and Evaluation of Cefixime Trihydrate Matrix Tablets Using HPMC, Sodium CMC, Ethyl Cellulose.

    PubMed

    Sirisolla, Janakidevi; Ramanamurthy, K V

    2015-01-01

    The objective of the present work is to design sustained release matrix tablets of cefixime trihydrate by incorporating drug in a matrix made up of release retardant polymers, which prolong drug release leading to minimization of the peak and valley effect in the plasma and provide patient convenience. The effect of combination of polymers on parameters like release pattern, release mechanism of the drug were studied. Total nine formulations each containing 200 mg of drug were prepared by direct compression method. The formulations F-1, F-2, F-3 were prepared with a 1:1 drug to polymer ratio using hydroxypropyl methylcellulose, carboxymethyl cellulose sodium and ethyl cellulose. F-4 was prepared with a 1:1 ratio of hydroxypropyl methylcellulose, carboxymethyl cellulose sodium, F-5 as prepared with a 1:1 ratio of hydroxypropyl methylcellulose and ethyl cellulose, F-6 was prepared with a 1:1 ratio of carboxymethyl cellulose sodium and ethyl cellulose, F-7, F-8, F-9 were prepared by using polymers hydroxypropyl methylcellulose, carboxymethyl cellulose sodium and ethyl cellulose in the ratios of 0.5:0.5:1, 0.5:1:0.5, and 1:0.5:0.5. Designed matrix tablets were evaluated for various pre-compression and post-compression parameters. Formulation F-5 showed 102.15 % release at the end of 12 h and it is selected as the best formulation. All Formulations followed zero order with non-Fickian diffusion method. PMID:26180278

  4. Formulation and Evaluation of Cefixime Trihydrate Matrix Tablets Using HPMC, Sodium CMC, Ethyl Cellulose

    PubMed Central

    Sirisolla, Janakidevi; Ramanamurthy, K. V.

    2015-01-01

    The objective of the present work is to design sustained release matrix tablets of cefixime trihydrate by incorporating drug in a matrix made up of release retardant polymers, which prolong drug release leading to minimization of the peak and valley effect in the plasma and provide patient convenience. The effect of combination of polymers on parameters like release pattern, release mechanism of the drug were studied. Total nine formulations each containing 200 mg of drug were prepared by direct compression method. The formulations F-1, F-2, F-3 were prepared with a 1:1 drug to polymer ratio using hydroxypropyl methylcellulose, carboxymethyl cellulose sodium and ethyl cellulose. F-4 was prepared with a 1:1 ratio of hydroxypropyl methylcellulose, carboxymethyl cellulose sodium, F-5 as prepared with a 1:1 ratio of hydroxypropyl methylcellulose and ethyl cellulose, F-6 was prepared with a 1:1 ratio of carboxymethyl cellulose sodium and ethyl cellulose, F-7, F-8, F-9 were prepared by using polymers hydroxypropyl methylcellulose, carboxymethyl cellulose sodium and ethyl cellulose in the ratios of 0.5:0.5:1, 0.5:1:0.5, and 1:0.5:0.5. Designed matrix tablets were evaluated for various pre-compression and post-compression parameters. Formulation F-5 showed 102.15 % release at the end of 12 h and it is selected as the best formulation. All Formulations followed zero order with non-Fickian diffusion method. PMID:26180278

  5. Encapsulation and modified-release of thymol from oral microparticles as adjuvant or substitute to current medications.

    PubMed

    Rassu, G; Nieddu, M; Bosi, P; Trevisi, P; Colombo, M; Priori, D; Manconi, P; Giunchedi, P; Gavini, E; Boatto, G

    2014-10-15

    The aim of this study was to encapsulate, thymol, in natural polymers in order to obtain (i) taste masking effect and, then, enhancing its palatability and (ii) two formulations for systemic and local delivery of herbal drug as adjuvants or substitutes to current medications to prevent and treat several human and animal diseases. Microspheres based on methylcellulose or hydroxypropyl methylcellulose phthalate (HPMCP) were prepared by spray drying technique. Microparticles were in vitro characterized in terms of yield of production, drug content and encapsulation efficiency, particle size, morphology and drug release. Both formulations were in vivo orally administered and pharmacokinetic analysis was carried out. The polymers used affect the release and, then, the pharmacokinetic profile of thymol. Encapsulation into methylcellulose microspheres leads to short half/life but bioavailability remarkably increases compared to the free thymol. In contrast, enteric formulation based on HPMCP shows very limited systemic absorption. These formulations could be proposed as alternative or adjuvants for controlling pathogen infections in human or animal. In particular, methylcellulose microspheres can be used for thymol systemic administration at low doses and HPMCP particles for local treatment of intestinal infections. PMID:25442269

  6. 21 CFR 524.960 - Flumethasone, neomycin sulfate, and polymyxin B sulfate ophthalmic solutions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    .... Dogs: 1 to 2 drops per eye, every 6 hours. (ii) Preparation without hydroxyproply methylcellulose. Dogs and cats: 2 to 3 drops per eye, every 4 hours. (2) Indications for use. Treatment of the inflammation, edema, and secondary bacterial infections associated with topical ophthalmological conditions of the...

  7. The influence of binder film thickness on the mechanical properties of binder films in tension.

    PubMed

    Ononokpono, O E; Spring, M S

    1988-02-01

    The physicomechanical properties of films of different thicknesses, made from methylcellulose and gelatinized maize starch, have been studied in tension. There was a linear relation between film thickness and tensile strength, toughness, elastic resilence and elongation at fracture. Young's modulus increased with decreasing film thickness particularly with films with a thickness of less than 15 micron. PMID:2897444

  8. 21 CFR 524.960 - Flumethasone, neomycin sulfate, and polymyxin B sulfate ophthalmic solutions.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    .... Dogs: 1 to 2 drops per eye, every 6 hours. (ii) Preparation without hydroxyproply methylcellulose. Dogs and cats: 2 to 3 drops per eye, every 4 hours. (2) Indications for use. Treatment of the inflammation, edema, and secondary bacterial infections associated with topical ophthalmological conditions of the...

  9. 21 CFR 524.960 - Flumethasone, neomycin sulfate, and polymyxin B sulfate ophthalmic solutions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    .... Dogs: 1 to 2 drops per eye, every 6 hours. (ii) Preparation without hydroxyproply methylcellulose. Dogs and cats: 2 to 3 drops per eye, every 4 hours. (2) Indications for use. Treatment of the inflammation, edema, and secondary bacterial infections associated with topical ophthalmological conditions of the...

  10. 21 CFR 524.960 - Flumethasone, neomycin sulfate, and polymyxin B sulfate ophthalmic solutions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    .... Dogs: 1 to 2 drops per eye, every 6 hours. (ii) Preparation without hydroxyproply methylcellulose. Dogs and cats: 2 to 3 drops per eye, every 4 hours. (2) Indications for use. Treatment of the inflammation, edema, and secondary bacterial infections associated with topical ophthalmological conditions of the...

  11. Gluten-free sorghum bread improved by sourdough fermentation: Biochemical, rheological and microstructural background

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was conducted to improve quality and theoretical understanding of gluten-free sorghum bread. Addition of 2% hydroxypropyl methylcellulose improved bread based on 105% water, 70% sorghum flour, and 30% potato starch. Nevertheless, a flat top and tendency towards a hole in the crumb remaine...

  12. TEXTILE WARP SIZE RECLAMATION USING THERMAL PRECIPITATION

    EPA Science Inventory

    The report describes a novel method for reclaiming size based on precipitation of the size material by heating the desize washwater. The method uses hydroxypropyl cellulose (HPC) or hydroxypropyl methylcellulose (HPMC) which are soluble in cool water but insoluble in warm water. ...

  13. Potential of Prolamins from Maize and Sorghum to Form Gluten-like Structures in Wheat-free Bread

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prolamins from maize (zeins) are known to form viscoelastic, extensible, cohesive dough when mixed together with starch and water above their glass transition temperature (Tg, approximately 28 °C). By adding hydroxypropyl methylcellulose (HPMC, a surface-active hydrocolloid) to this formulation, lea...

  14. 21 CFR 182.1745 - Sodium carboxymethylcellu-lose.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Sodium carboxymethylcellu-lose. 182.1745 Section... GRAS Food Substances § 182.1745 Sodium carboxymethylcellu-lose. (a) Product. Sodium carboxy-methylcellulose is the sodium salt of carboxymethylcellulose not less than 99.5 percent on a dry-weight...

  15. 21 CFR 182.1745 - Sodium carboxymethylcellu-lose.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Sodium carboxymethylcellu-lose. 182.1745 Section... (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Multiple Purpose GRAS Food Substances § 182.1745 Sodium carboxymethylcellu-lose. (a) Product. Sodium carboxy-methylcellulose is the sodium salt of carboxymethylcellulose...

  16. 21 CFR 182.1745 - Sodium carboxymethylcellu-lose.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium carboxymethylcellu-lose. 182.1745 Section... GRAS Food Substances § 182.1745 Sodium carboxymethylcellu-lose. (a) Product. Sodium carboxy-methylcellulose is the sodium salt of carboxymethylcellulose not less than 99.5 percent on a dry-weight...

  17. 21 CFR 182.1745 - Sodium carboxymethylcellu-lose.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Sodium carboxymethylcellu-lose. 182.1745 Section... GRAS Food Substances § 182.1745 Sodium carboxymethylcellu-lose. (a) Product. Sodium carboxy-methylcellulose is the sodium salt of carboxymethylcellulose not less than 99.5 percent on a dry-weight...

  18. Adiponectin in Hamster: Characterization and Functions in Soluble Dietary Fiber Mediated Lipid Homeostatis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aim: The hypocholesterolemic and hypoglycemic effects of various natural and semisynthetic dietary fibers have been studied in the past for their potential use in the prevention and improvement of metabolic syndrome. Among these dietary fibers, hydroxypropyl methylcellulose (HPMC) has been shown to...

  19. HPMC supplementation reduces fatty liver, intestinal permeability, and insulin resistance with altered hepatic gene expression in diet-induced obese mice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of hydroxypropyl methylcellulose (HPMC), a highly viscous nonfermentable soluble dietary fiber, were evaluated on global hepatic gene profiles, steatosis and insulin resistance in high-fat (HF) diet-induced obese (DIO) mice. DIO C57BL/6J mice were fed a HF diet supplemented with either ...

  20. Development of polysaccharides-based edible coatings for citrus fruits: a layer-by-layer approach.

    PubMed

    Arnon, Hadar; Granit, Rina; Porat, Ron; Poverenov, Elena

    2015-01-01

    Biodegradable coatings for citrus fruits that would replace the currently used polyethylene-based waxes, are of great interest. Methylcellulose (MC), hydroxypropyl methylcellulose (HPMC), carboxymethyl cellulose (CMC) and chitosan (CH) coatings were examined on the most sensitive citrus fruit model: mandarins. Among the examined polysaccharides, CMC provided mandarins with the best firmness, lowest weight loss and satisfying gloss, while not affecting natural flavour and the respiration process. To enhance coating performance, glycerol, oleic acid and stearic acid were added; however, mandarin quality generally deteriorated with these additives. Then, a layer-by-layer (LBL) approach was applied. LbL coatings, based on a combination of two polysaccharides, CMC as an internal layer and chitosan as an external layer, gave the best performance. Different concentrations of chitosan were examined. The LbL coatings notably improved all quantified parameters of fruit quality, proving that polysaccharide-based edible coating may offer an alternative to synthetic waxes. PMID:25053081

  1. Characterization of new eye drops with choline salicylate and assessment of their irritancy by in vitro short time exposure tests

    PubMed Central

    Wroblewska, Katarzyna; Kucinska, Małgorzata; Murias, Marek; Lulek, Janina

    2014-01-01

    The aim of our study was to examine the irritation potential of new eye drops containing 2% choline salicylate (CS) as an active pharmaceutical ingredient (API) and various polymers increasing eye drop viscosity (hydroxyethylcellulose, hydroxypropyl methylcellulose, methylcellulose, polyvinyl alcohol, polyvinylpyrrolidone). The standard method for assessing the potential of irritating substances has been the Draize rabbit eye test. However the European Centre for Validation of Alternative Methods and the Coordinating Committee for Validation of Alternative Methods recommend, short time exposure (STE) in vitro tests as an alternative method for assessing eye irritation. The eye irritation potential was determined using cytotoxicity test methods for rabbit corneal cell line (SIRC) after 5 min exposure. The viability of cells was determined using two cytotoxicity assays: MTT and Neutral Red Uptake. According to the irritation rankings for the short time exposure test, all tested eye drops are classified as non-irritating (cell viability >70%). PMID:27134543

  2. Fibril Formation and Phase Separation in Aqueous Cellulose Ethers

    NASA Astrophysics Data System (ADS)

    Maxwell, Amanda; Schmidt, Peter; McAllister, John; Lott, Joseph; Bates, Frank; Lodge, Timothy

    Aqueous solutions of many cellulose ethers are known to undergo thermoreversible gelation and phase separation upon heating to form turbid hydrogels, but the mechanism and resulting structures have not been well understood. Turbidity, light scattering and small-angle neutron scattering (SANS) are used to show that hydroxypropyl methylcellulose (HPMC) chains are dissolved in water below 50 °C and undergo phase separation at higher temperatures. At 70 °C, at sufficiently high concentrations in water, HPMC orders into fibrillar structures with a well-defined radius of 18 +/- 2 nm, as characterized by cryogenic transmission electron microscopy and SANS. The HPMC fibril structure is independent of concentration and heating rate. However, HPMC fibrils do not form a percolating network as readily as is seen in methylcellulose, resulting in a lower hot-gel modulus, as demonstrated by rheology.

  3. Development of cellulose derivatives as novel enteric coating agents soluble at pH 3.5-4.5 and higher.

    PubMed

    Kokubo, H; Obara, S; Minemura, K; Tanaka, T

    1997-08-01

    Hydroxypropyl methylcellulose (HPMC) was selected as a base polymer to develop novel enteric coating agents for acid protection which can dissolve at pH around 4, and was modified with trimellitic acid or maleic acid at various degrees of substitution. These carboxylic acids have higher dissociation constants and higher solubility in water than the carboxylic acids of existing enteric coating polymers. The synthesized polymers were micronized and dispersed in aqueous medium to determine their pKa values by potentiometric titration. The pH of dissolution and the water vapor permeability of the cast films prepared from organic solutions were also evaluated. Hydroxypropyl methylcellulose trimellitate (HPMCT) showed good acid resistance, and the pH at which it dissolves can be controlled in the range of pH 3.5 to 4.5 by varying the content of trimellityl groups and the methoxyl substitution of the base polymer. PMID:9301034

  4. Characterization of new eye drops with choline salicylate and assessment of their irritancy by in vitro short time exposure tests.

    PubMed

    Wroblewska, Katarzyna; Kucinska, Małgorzata; Murias, Marek; Lulek, Janina

    2015-09-01

    The aim of our study was to examine the irritation potential of new eye drops containing 2% choline salicylate (CS) as an active pharmaceutical ingredient (API) and various polymers increasing eye drop viscosity (hydroxyethylcellulose, hydroxypropyl methylcellulose, methylcellulose, polyvinyl alcohol, polyvinylpyrrolidone). The standard method for assessing the potential of irritating substances has been the Draize rabbit eye test. However the European Centre for Validation of Alternative Methods and the Coordinating Committee for Validation of Alternative Methods recommend, short time exposure (STE) in vitro tests as an alternative method for assessing eye irritation. The eye irritation potential was determined using cytotoxicity test methods for rabbit corneal cell line (SIRC) after 5 min exposure. The viability of cells was determined using two cytotoxicity assays: MTT and Neutral Red Uptake. According to the irritation rankings for the short time exposure test, all tested eye drops are classified as non-irritating (cell viability >70%). PMID:27134543

  5. Stress crack resistance of some pigmented and unpigmented tablet film coating systems.

    PubMed

    Okhamafe, A O; York, P

    1985-07-01

    Stress crack resistance parameters--tensile strength: Young's modulus ratio, relative surface energy, and toughness index--have been examined for unpigmented free films of hydroxypropyl methylcellulose containing polyvinyl alcohol, and polyethylene glycols 400 and 1000, as well as similar film systems pigmented with either talc or titanium dioxide. Incorporation of either polyvinyl alcohol or polyethylene glycols 400 and 1000 in hydroxypropyl methylcellulose film coatings eliminated the incidence of edge splitting in the coated tablets. Increase in pigment concentration generally led to a decrease in the crack resistance of pigmented films. There was a relation between the stress crack resistance of pigmented free films and the incidence of edge splitting of corresponding film coatings applied to aspirin tablets--generally, the higher the crack resistance the lower the incidence of edge splitting. A similar relationship applied to the unpigmented films only when the tensile strength: Young's modulus ratio was considered. PMID:2863345

  6. Effect of alginate/carboxyl methyl cellulose composite coating incorporated with clove essential oil on the quality of silver carp fillet and Escherichia coli O157:H7 inhibition during refrigerated storage.

    PubMed

    Jalali, Nastaran; Ariiai, Peiman; Fattahi, Esmaeil

    2016-01-01

    The effects of alginate/carboxyl methylcellulose composite coating incorporated with clove essential oil on quality of silver carp fillet chilled storage (4 + 1 °C) were examined over a period of 16 days. The control samples (c), alginate/carboxyl methylcellulose coating (C-A), alginate/carboxyl methylcellulose composite coating incorporated with clove essential oil (with different concentration 1 and 1.5 %) (C-A + CEO1 % and C-A + CEO 15 % respectively) were analyzed by bacteriological (total viable counts (TVC) and total psychrotrophic counts (TPC)), biochemical (Peroxide value (PV), free fatty acid (FFA), total volatile base nitrogen (TVB-N), and pH) and sensory characteristics. Also, the efficacy of these treatments was investigated in control of the population of Eschershia coli O157:H7 inoculated in silver carp fillet. According to the obtained results, C-A + CEO 1.5 % showed lowest (p < 0.05) and acceptable biochemical, bacteriological and sensory characteristics attributes up to 16 days storage at 4 °C compared to the others. Also, this treated sample was acceptable even at the end of the 16-day storage and it could reduce the population of E. coli O157:H7 below the acceptable level (<2) from day 4 until the end of the storage period. The results indicate Alginate/carboxyl methylcellulose composite coating with clove essential oil might be recommended as a preservative in the meat products. PMID:26787996

  7. Electrochemical cell

    DOEpatents

    Redey, Laszlo I.; Vissers, Donald R.; Prakash, Jai

    1994-01-01

    An electrochemical cell having an alkali metal negative electrode such as sodium and a positive electrode including Ni or transition metals, separated by a .beta." alumina electrolyte and NaAlCl.sub.4 or other compatible material. Various concentrations of a bromine, iodine and/or sulfur containing additive and pore formers are disclosed, which enhance cell capacity and power. The pore formers may be the ammonium salts of carbonic acid or a weak organic acid or oxamide or methylcellulose.

  8. Structural, surface wettability and antibacterial properties of HPMC-ZnO nanocomposite

    SciTech Connect

    Rao, B. Lakshmeesha; Asha, S.; Madhukumar, R.; Latha, S.; Gowda, Mahadeva; Shetty, G. Rajesha; Sangappa; Chandra, K. Sharath; Naik, Prashantha

    2014-04-24

    The developed hydroxypropyl methylcellulose (HPMC)/Zinc oxide (ZnO) nanocomposite films were examined for structural property and surface wettability using X-ray diffraction and contact angle measurement. Antibacterial activity of these films was evaluated as a function of ZnO concentration. The microstructuralline parameters ( and (g in %)) decreased with increasing concentration of ZnO nanoparticles and there was increase in hydrophilicity. Addition of ZnO nanoparticles in films resulted in antimicrobial activity against tested microorganisms.

  9. The Aminosteroid Derivative RM-133 Shows In Vitro and In Vivo Antitumor Activity in Human Ovarian and Pancreatic Cancers

    PubMed Central

    Kenmogne, Lucie Carolle; Ayan, Diana; Roy, Jenny; Maltais, René; Poirier, Donald

    2015-01-01

    Ovarian and pancreatic cancers are two of the most aggressive and lethal cancers, whose management faces only limited therapeutic options. Typically, these tumors spread insidiously accompanied first with atypical symptoms, and usually shift to a drug resistance phenotype with the current pharmaceutical armamentarium. Thus, the development of new drugs acting via a different mechanism of action represents a clear priority. Herein, we are reporting for the first time that the aminosteroid derivative RM-133, developed in our laboratory, displays promising activity on two models of aggressive cancers, namely ovarian (OVCAR-3) and pancreatic (PANC-1) cancers. The IC50 value of RM-133 was 0.8 μM and 0.3 μM for OVCAR-3 and PANC-1 cell lines in culture, respectively. Based on pharmacokinetic studies on RM-133 using 11 different vehicles, we selected two main vehicles: aqueous 0.4% methylcellulose:ethanol (92:8) and sunflower oil:ethanol (92:8) for in vivo studies. Using subcutaneous injection of RM-133 with the methylcellulose-based vehicle, growth of PANC-1 tumors xenografted to nude mice was inhibited by 63%. Quite interestingly, RM-133 injected subcutaneously with the methylcellulose-based or sunflower-based vehicles reduced OVCAR-3 xenograft growth by 122% and 100%, respectively. After the end of RM-133 treatment using the methylcellulose-based vehicle, OVCAR-3 tumor growth inhibition was maintained for ≥ 1 week. RM-133 was also well tolerated in the whole animal, no apparent sign of toxicity having been detected in the xenograft studies. PMID:26660672

  10. Bimodal Gastroretentive Drug Delivery Systems of Lamotrigine: Formulation and Evaluation

    PubMed Central

    Poonuru, R. R.; Gonugunta, C. S. R

    2014-01-01

    Gastroretentive bimodal drug delivery systems of lamotrigine were developed using immediate release and extended release segments incorporated in a hydroxypropyl methylcellulose capsule and in vitro and in vivo evaluations were conducted. In vivo radiographic studies were carried out for the optimized formulation in healthy human volunteers with replacement of drug polymer complex by barium sulphate and the floating time was noted. Here the immediate release segment worked as loading dose and extended release segment as maintenance dose. The results of release studies of formulations with hydrophillic matrix to formulations with dual matrix hydroxypropyl methylcellulose acetate succinate shown that as the percentage of polymer increased, the release decreased. Selected formulation F2 having F-Melt has successfully released the drug within one hour and hydrophillic matrix composing polyethylene oxide with 5% hydroxypropyl methylcellulose acetate succinate showed a lag time of one hour and then extended its release up to 12th hour with 99.59% drug release following zero order kinetics with R2 value of 0.989. The Korsmeyer-Peppas equation showed the R2 value to be 0.941 and n value was 1.606 following non-Fickian diffusion pattern with supercase II relaxation mechanism. Here from extended release tablet the drug released slowly from the matrix while floating. PMID:25593380

  11. Cyclodextrin-based telmisartan ophthalmic suspension: Formulation development for water-insoluble drugs.

    PubMed

    Muankaew, Chutimon; Jansook, Phatsawee; Sigurđsson, Hákon Hrafn; Loftsson, Thorsteinn

    2016-06-30

    In this study, cyclodextrin-based aqueous eye drop suspension of the water insoluble drug telmisartan was developed. Formation of a drug/γ-cyclodextrin complex was enabled by preventing formation of a poorly water-soluble zwitterion using a volatile base that was removed upon drying of the complex powder. Hydroxypropyl methylcellulose was shown to have the overall best effect, stabilizing the complexes without hampering the drug release from the formulation. Two strategies for preparing cyclodextrin-based aqueous eye drop suspensions of telmisartan were investigated, one where hydroxypropyl methylcellulose was added to the medium during preparation of the drug/γ-cyclodextrin complex powder (ternary complex) and the other where hydroxypropyl methylcellulose was added to the complex powder after preparation of the complex (binary complex). The complexation was characterized by DSC, FT-IR and (1)H NMR and the eye drop suspensions formed were examined regarding their stability and in vitro mucoadhesion property. The ternary complex exhibited inferior mucoadhesive property compared to the binary complex. However, the ternary complex was more stable as no notable change in particle size and particle size distribution was observed during storage at 4°C over 6 months (p<0.05) with the mean particle size determined between 2.0 and 2.5μm. PMID:27139144

  12. Effect of Different Polymer Concentration on Drug Release Rate and Physicochemical Properties of Mucoadhesive Gastroretentive Tablets

    PubMed Central

    Agarwal, Shweta; Murthy, R. S. R.

    2015-01-01

    Mucoadhesive tablets have emerged as potential candidates for gastroretentive drug delivery providing controlled release along with prolonged gastric residence time. Gastroretentive mucoadhesive tablets could result in increased bioavailability due to prolonged gastric residence time. A hydrophilic matrix system was developed as mucoadhesion is achievable on appropriate wetting and swelling of the polymers used. The polymers were so chosen so as to provide a balance between swelling, mucoadhesion and drug release. The polymers chosen were hydroxypropyl methylcellulose K4M, chitosan, and Carbopol 934. The concentrations of these polymers used has a great impact on the physicochemical properties of the resulting formulation. The tablets were formulated using wet granulation method and tranexamic acid was used as the model drug. The prepared tablets were characterized for size, shape, appearance, hardness, friability, weight variation, swelling, mucoadhesion and in vitro drug release. Several batches of tablets were prepared by varying the ratio of hydroxypropyl methylcellulose K4M and Chitosan. The batches having a greater ratio of chitosan showed higher rate of swelling, greater erosion, less mucoadhesion and faster release rate of the drug whereas the batches having greater ratio of hydroxypropyl methylcellulose K4M showed lesser rate of swelling, less erosion, better mucoadhesion and a smaller drug release rate. The level of carbopol was kept constant in all the batches. PMID:26997698

  13. Effect of Different Polymer Concentration on Drug Release Rate and Physicochemical Properties of Mucoadhesive Gastroretentive Tablets.

    PubMed

    Agarwal, Shweta; Murthy, R S R

    2015-01-01

    Mucoadhesive tablets have emerged as potential candidates for gastroretentive drug delivery providing controlled release along with prolonged gastric residence time. Gastroretentive mucoadhesive tablets could result in increased bioavailability due to prolonged gastric residence time. A hydrophilic matrix system was developed as mucoadhesion is achievable on appropriate wetting and swelling of the polymers used. The polymers were so chosen so as to provide a balance between swelling, mucoadhesion and drug release. The polymers chosen were hydroxypropyl methylcellulose K4M, chitosan, and Carbopol 934. The concentrations of these polymers used has a great impact on the physicochemical properties of the resulting formulation. The tablets were formulated using wet granulation method and tranexamic acid was used as the model drug. The prepared tablets were characterized for size, shape, appearance, hardness, friability, weight variation, swelling, mucoadhesion and in vitro drug release. Several batches of tablets were prepared by varying the ratio of hydroxypropyl methylcellulose K4M and Chitosan. The batches having a greater ratio of chitosan showed higher rate of swelling, greater erosion, less mucoadhesion and faster release rate of the drug whereas the batches having greater ratio of hydroxypropyl methylcellulose K4M showed lesser rate of swelling, less erosion, better mucoadhesion and a smaller drug release rate. The level of carbopol was kept constant in all the batches. PMID:26997698

  14. [Experimental data on the penetration of gentamicin into the media of the eye].

    PubMed

    Shchekotova, I G

    1976-12-01

    Penetration of Soviet gentamicin into the humor of the anterior chamber and vitreous body of the eye with aseptic inflammation was studied after the antibiotic administration by various routed, i.e. instillations of 8 per cent antibiotic solution and 8 per cent antibiotic solution methylcellulose into the conjunctival sac, injections of 20 mg of gentamicin subconjunctivally and retrobulbarly, injections of gentamicin intramuscularly in doses of 0.6 mg/kg. The studies showed that gentamicin penetrated into the humor of the anterior chamber and vitreous body of the eye after all the administration routes mentioned above in concentrations sufficient for the antibiotic antimicrobial effect and persisted in the eye media for prolong periods of time (24--48 hours). The highest concentrations of the antibiotic in the tumor of the anterior chamber were achieved after its administration subconjunctivally or after instillation of its 8 per cent on methylcellulose, while in the vitreous body its highest concentrations were achieved after injections subconjunctively, retrobulbarly or intramuscularly. Instillations of gentamicin solution on methylcellulose provided higher and more persistant concentrations of the antibiotic in the humor as compared to instillations of its aqueous solutions. Retrobulbar injections of gentamicin had no advantages as compared to subconjunctival administration with respect to providing higher concentrations of the antibiotic in the eye media. PMID:1020943

  15. Effect of additives on physicochemical properties in amorphous starch matrices.

    PubMed

    Liang, Jun; Wang, Simon; Ludescher, Richard D

    2015-03-15

    The effect of the addition of non-reducing sugars or methylcellulose on the matrix physical properties and rate of non-enzymatic browning (NBR) between exogenous glucose+lysine in a starch-based glassy matrix were studied, using the methods of luminescence and FTIR. Amorphous starch-based matrices were formulated by rapidly dehydrating potato starch gel mixed with additives at weight ratios of 7:93 (additive:starch). Data on the phosphorescence emission energy and lifetime from erythrosin B dispersed in the matrices indicated that sugars decreased starch matrix mobility in a Tg-dependent manner, except for trehalose that interacted with starch in a unique mode, while methylcellulose, the additive with the highest Tg, increased the molecular mobility. Using FTIR, we found that methylcellulose decreased the strength of hydrogen bond network and sugars enhanced the hydrogen bond strength in the order: trehalose>maltitol>sucrose. Comparing those changes with the rate of NBR between exogenous glucose+lysine, we suggest that NBR rates are primarily influenced by matrix mobility, which is modulated by the hydrogen bond network, and interactions among components. PMID:25308673

  16. Mechanically Enhanced Liquid Interfaces at Human Body Temperature Using Thermosensitive Methylated Nanocrystalline Cellulose.

    PubMed

    Scheuble, N; Geue, T; Kuster, S; Adamcik, J; Mezzenga, R; Windhab, E J; Fischer, P

    2016-02-01

    The mechanical performance of materials at oil/water interfaces after consumption is a key factor affecting hydrophobic drug release. In this study, we methylated the surface of nanocrystalline cellulose (NCC) by mercerization and dimethyl sulfate exposure to produce thermosensitive biopolymers. These methylated NCC (metNCC) were used to investigate interfacial thermogelation at air/water and medium-chain triglyceride (MCT)/water interfaces at body temperature. In contrast to bulk fluid dynamics, elastic layers were formed at room temperature, and elasticity increased significantly at body temperature, which was measured by interfacial shear and dilatational rheology in situ. This unique phenomenon depends on solvent quality, temperature, and polymer concentration at interfaces. Thus, by adjusting the degree of hydrophobicity of metNCC, the interfacial elasticity and thermogelation of the interfaces could be varied. In general, these new materials (metNCC) formed more brittle interfacial layers compared to commercial methylcellulose (MC A15). Thermogelation of methylcellulose promotes attractive intermolecular forces, which were reflected in a change in self-assembly of metNCC at the interface. As a consequence, layer thickness and density increased as a function of temperature. These effects were measured by atomic force microscopy (AFM) images of the displaced interface and confirmed by neutron reflection. The substantial structural and mechanical change of methylcellulose interfaces at body temperature represents a controllable encapsulation parameter allowing optimization of lipid-based drug formulations. PMID:26779953

  17. Adhesion of rice flour-based batter to chicken drumsticks evaluated by laser scanning confocal microscopy and texture analysis.

    PubMed

    Mukprasirt, A; Herald, T J; Boyle, D L; Rausch, K D

    2000-09-01

    The convenience and appeal of battered or breaded products have resulted in a sales increase of 100% since 1980. Because of the rapid growth of the Asian-American population and increasing consumption of rice and rice products, rice flour is a logical alternative for wheat flour in traditional batter formulation. The effects of ingredients used in rice flour-based batters on adhesion characteristic for deep-fat fried chicken drumsticks were studied by laser scanning confocal microscopy (LSCM) and texture analysis. Raw chicken drumsticks were predusted with egg albumin powder before dipping into batters prepared from combinations of rice flour, yellow corn flour, oxidized cornstarch, methylcellulose, or xanthan gum. The drumsticks were fried at 175+/-5 C until the internal temperature reached at least 71 C. For LSCM, samples were fixed overnight and were sectioned by vibratome (200 microm) before viewing. Batter adhesion was determined using an attachment specifically designed for chicken drumsticks. Microstructural analysis showed that batter formulated with a 50:50 mixture of rice and corn flours adhered better to drumsticks than batter with other rice flour ratios. Xanthan gum (0.2%) or methylcellulose (0.3%) alone had poor adhesion to chicken skin. However, when combined with other ingredients, xanthan gum increased the amount of batter pick-up before frying by increasing viscosity. Egg albumin significantly facilitated batter adhesion. The results from texture analysis supported the microstructural studies. As rice flour ratio increased from 50 to 70%, the binding force decreased. Rice flour showed potential as an alternative to wheat flour for batter formulas when the appropriate levels of oxidized starch, xanthan gum, and methylcellulose were included in the formulation. PMID:11020085

  18. Polymer incompatibility as a potential tool for polyphenol recovery from olive mill wastewater.

    PubMed

    Hajji, Fuad; Kunz, Benno; Weissbrodt, Jenny

    2014-08-01

    Experiments were designed and preformed in consideration of polymer type (proteins, i.e. caseinate and ovalbumin, and polysaccharides, i.e. alginate and methylcellulose), charge character and polysaccharide concentrations, intended to understand how the polymer properties determine both phase separation and polyphenol partitioning from olive mill wastewater (OMW). The highest yield of polyphenols (YBP=92.9%) was achieved in an aqueous two-phase system (ATPS) using an ovalbumin-methylcellulose system (OMCS) in comparison to ATPS with caseinate-alginate system (CAS; YBP=85.8%) or caseinate methylcellulose system (CMCS; YBP=74%). The performance of CMCS for the ATPS partitioning of polyphenols in OMW was found to depend on the addition of salt (sodium chloride). The use of centrifugation as assistive technology appears to be necessary for the polyphenol partitioning in ATPS using OMCS. In contrast to these polymer systems, CAS caused a rapid ATPS without resorting to centrifugation and salt, mainly because of strong electrostatic repulsion between alginate and caseinate. In this regard, CAS in phase-separated OMW obtained a partition coefficient of protein (KP1) of 0.04, a tie-line length (TLL) of 10.47% (w/w) and a phase volume ratio (VR) of 0.7. Thus, ATPS based on CAS represent an efficient and environmentally friendly concept in recovery of polyphenols from OMW. The spray drying of the caseinate-polyphenol-rich phase from CAS could become a dry intermediate product with potential use in the food and non-food industry. PMID:24629933

  19. The formation and characterization of hydrocortisone-loaded poly((+/-)-lactide) microspheres.

    PubMed

    Cavalier, M; Benoit, J P; Thies, C

    1986-04-01

    The solvent evaporation process has been used to form hydrocortisone-loaded microspheres from poly((+/-)-lactide) (PLA) and a lactide-glycolide copolymer (65/35). Methylene chloride was the casting solvent. Partially hydrolysed (88%) poly(vinyl alcohol) and methylcellulose were used as aqueous phase emulsifiers. Methylcellulose was preferred, because it gave stable emulsions as the amount of hydrocortisone being encapsulated increased whereas poly(vinyl alcohol) did not. With methylcellulose as the emulsifier, a broad size range of spherical microspheres containing up to 50% (w/w) hydrocortisone could be prepared. Thermal and X-ray analyses established that poly((+/-)-lactide) microspheres containing hydrocortisone retained thermal events characteristic of both materials. This is evidence that such microspheres contain, to some extent, crystalline hydrocortisone domains dispersed in a PLA matrix. But most of the encapsulated drug was molecularly dispersed in the PLA glass. The stability of hydrocortisone in microspheres was evaluated in different storage conditions: no degradation of drug was found. The release of hydrocortisone from 250-350 microns diameter microspheres into agitated 37 degrees C water (nitrogen atmosphere) was determined by HPLC analysis. The microspheres evaluated had initial hydrocortisone payloads of 12 to 47% (w/w). The rate of drug release increased as the initial drug payload carried by the microspheres increased. The release data are not adequately described by zero order, first order, or square-root-of-time release kinetics. Drug release from microspheres that contain 12% (w/w) hydrocortisone approached a plateau value well below the amount of drug actually carried by the microspheres. This is particularly true for hydrocortisone encapsulated in lactide-glycolide polymer. PMID:2872287

  20. Electrochemical cell

    DOEpatents

    Redey, L.I.; Vissers, D.R.; Prakash, J.

    1994-08-23

    An electrochemical cell is described having an alkali metal negative electrode such as sodium and a positive electrode including Ni or transition metals, separated by a [beta] alumina electrolyte and NaAlCl[sub 4] or other compatible material. Various concentrations of a bromine, iodine and/or sulfur containing additive and pore formers are disclosed, which enhance cell capacity and power. The pore formers may be the ammonium salts of carbonic acid or a weak organic acid or oxamide or methylcellulose. 6 figs.

  1. PROCESS OF MAKING SHAPED FUEL FOR NUCLEAR REACTORS

    DOEpatents

    O'Leary, W.J.; Fisher, E.A.

    1964-02-11

    A process for making uranium dioxide fuel of great strength, density, and thermal conductivity by mixing it with 0.1 to 1% of a densifier oxide (tin, aluminum, zirconium, ferric, zinc, chromium, molybdenum, titanium, or niobium oxide) and with a plasticizer (0.5 to 3% of bentonite and 0.05 to 2% of methylcellulose, propylene glycol alginate, or ammonium alginate), compacting the mixture obtained, and sintering the bodies in an atmosphere of carbon monoxide or carbon dioxide, with or without hydrogen, or of a nitrogen-hydrogen mixture is described. (AEC)

  2. Prevention of Peritoneal Adhesions Using Polymeric Rheological Blends

    PubMed Central

    Hoare, Todd; Yeo, Yoon; Bellas, Evangelia; Bruggeman, Joost P.

    2014-01-01

    The effectiveness of rheological blends of high molecular weight hyaluronic acid (HA) and low molecular weight hydroxypropyl methylcellulose (HPMC) in the prevention of peritoneal adhesions post-surgery is demonstrated. The physical mixture of the two carbohydrates increased the dwell time in the peritoneum while significantly improving the injectability of the polymer compared to hyaluronic acid alone. HA-HPMC treatment decreased the total adhesion area by ~70% relative to a saline control or no treatment in a repeated cecal injury model in the rabbit. No significant cytotoxicity and minimal inflammation was associated with the blend, and no chemical or physical processing was required prior to their use beyond simple mixing. PMID:24365709

  3. Certain problems of space biotechnology

    NASA Technical Reports Server (NTRS)

    Gilyarov, V. N.

    1980-01-01

    Experiments in the field of biotechnology conducted by the USA Apollo and Skylab space probes are described, as well as the joint Soviet-American Apollo-Soyuz Test Project (ASTP). Experiments in electrophoretic separation in space of biological compounds in a liquid medium are detailed. Space processing of vaccines and separation of human and animal cells are described. Methyl-cellulose, a coating for use in electrophoresis was developed. Erythropoietin, which stimulates the formation of red blood corpuscles in bone marrow, was obtained in pure form.

  4. Control of electroosmosis in coated quartz capillaries

    NASA Technical Reports Server (NTRS)

    Herren, Blair J.; Van Alstine, James; Snyder, Robert S.; Shafer, Steven G.; Harris, J. Milton

    1987-01-01

    The effectiveness of various coatings for controlling the electroosmotic fluid flow that hinders electrophoretic processes is studied using analytical particle microelectrophoresis. The mobilities of 2-micron diameter glass and polystyrene latex spheres (exhibiting both negative and zero effective surface charge) were measured in 2-mm diameter quartz capillaries filled with NaCl solutions within the 3.5-7.8 pH range. It is found that capillary inner surface coatings using 5000 molecular weight (or higher) poly(ethylene glycol): significantly reduced electroosmosis within the selected pH range, were stable for long time periods, and appeared to be more effective than dextran, methylcellulose, or silane coatings.

  5. Effect of iontophoresis and permeation enhancers on the permeation of an acyclovir gel.

    PubMed

    Vaghani, Subhash S; Gurjar, Mitesh; Singh, Sachin; Sureja, Sunil; Koradia, Shailesh; Jivani, N P; Patel, M M

    2010-10-01

    The purpose of the present study was to explore the combined effect of chemical enhancers and iontophoresis on the in vitro permeation of acyclovir gel across porcine skin. Acyclovir gel was formulated using carbopol 940 and hydroxypropyl methylcellulose K4M (HPMC K4M). Effect of drug concentration on the delivery of acyclovir was examined. Increasing drug concentration of acyclovir enhanced its flux across the skin. Incorporation of permeation enhancers (menthol, n-methyl-2-pyrrolidone and polyethylene glycol 400) into the gel resulted in enhanced acyclovir permeation when combined with iontophoresis. Menthol showed the highest drug permeation and when combined with iontophoresis it significantly increased the acyclovir skin permeation. PMID:20695844

  6. Evaluation of thermal gelation behavior of different cellulose ether polymers by rheology

    NASA Astrophysics Data System (ADS)

    Balaghi, S.; Edelby, Y.; Senge, B.

    2014-05-01

    Hydroxypropylmethylcellulose (HPMC) and Methylcellulose (MC) are cellulose ethers which can be dispersed in water and used as thickeners, emulsifiers, binders, film formers, and water-retention agents due to their hydrophilic and hydrophobic characteristics. In this study, various types of HPMCs, in comparison with two types of MCs were examined. The formed gels of the different cellulose ethers showed specific and various structural formation and network properties. The degree of methylation (Meth.) and hydroxypropylation (HyPr.) affected drastically the heat-induced gelation of the examined cellulose ethers.

  7. Multiple bidirectional alterations of phenotype and changes in proliferative potential during the in vitro and in vivo passage of clonal mast cell populations derived from mouse peritoneal mast cells

    SciTech Connect

    Kanakura, Y.; Thompson, H.; Nakano, T.; Yamamura, T.; Asai, H.; Kitamura, Y.; Metcalfe, D.D.; Galli, S.J.

    1988-09-01

    Mouse peritoneal mast cells (PMC) express a connective tissue-type mast cell (CTMC) phenotype, including reactivity with the heparin-binding fluorescent dye berberine sulfate and incorporation of (35S) sulfate predominantly into heparin proteoglycans. When PMC purified to greater than 99% purity were cultured in methylcellulose with IL-3 and IL-4, approximately 25% of the PMC formed colonies, all of which contained both berberine sulfate-positive and berberine sulfate-negative mast cells. When these mast cells were transferred to suspension culture, they generated populations that were 100% berberine sulfate-negative, a characteristic similar to that of mucosal mast cells (MMC), and that synthesized predominantly chondroitin sulfate (35S) proteoglycans. When ''MMC-like'' cultured mast cells derived from WBB6F1-+/+ PMC were injected into the peritoneal cavities of mast cell-deficient WBB6F1-W/Wv mice, the adoptively transferred mast cell population became 100% berberine sulfate-positive. In methylcellulose culture, these ''second generation PMC'' formed clonal colonies containing both berberine sulfate-positive and berberine sulfate-negative cells, but exhibited significantly less proliferative ability than did normal +/+ PMC. Thus, clonal mast cell populations initially derived from single PMC exhibited multiple and bidirectional alterations between CTMC-like and MMC-like phenotypes. However, this process was associated with a progressive diminution of the mast cells' proliferative ability.

  8. Development and physical characterization of polymer-fish oil bigel (hydrogel/oleogel) system as a transdermal drug delivery vehicle.

    PubMed

    Rehman, Khurram; Mohd Amin, Mohd Cairul Iqbal; Zulfakar, Mohd Hanif

    2014-01-01

    Polymer-Fish oil bigel (hydrogel/oleogel colloidal mixture) was developed by using fish oil and natural (sodium alginate) and synthetic (hydroxypropyl methylcellulose) polymer for pharmaceutical purposes. The bigels were closely monitored and thermal, rheological and mechanical properties were compared with the conventional hydrogels for their potential use as an effective transdermal drug delivery vehicle. Stability of the fish oil fatty acids (especially eicosapentanoic acid, EPA and docosahexanoic acid, DHA) was determined by gas chromatography and the drug content (imiquimod) was assessed with liquid chromatography. Furthermore, in vitro permeation study was conducted to determine the capability of the fish oil-bigels as transdermal drug delivery vehicle. The bigels showed pseudoplastic rheological features, with excellent mechanical properties (adhesiveness, peak stress and hardness), which indicated their excellent spreadability for application on the skin. Bigels prepared with mixture of sodium alginate and fish oil (SB1 and SB2), and the bigels prepared with the mixture of hydroxypropyl methylcellulose and fish oil (HB1-HB3) showed high cumulative permeation and drug flux compared to hydrogels. Addition of fish oil proved to be beneficial in increasing the drug permeation and the results were statistically significant (p < 0.05, one-way Anova, SPSS 20.0). Thus, it can be concluded that bigel formulations could be used as an effective topical and transdermal drug delivery vehicle for pharmaceutical purposes. PMID:25252741

  9. Formulation and optimization of mucoadhesive bilayer buccal tablets of atenolol using simplex design method

    PubMed Central

    Shirsand, SB; Suresh, Sarasija; Keshavshetti, GG; Swamy, PV; Reddy, P Vijay Prakash

    2012-01-01

    Introduction: In the present study, mucoadhesive buccal bilayer tablets of atenolol were fabricated with the objective of avoiding first pass metabolism and to improve its bioavailability with reduction in dosing frequency. Hence, the aim of this work was to design oral controlled release mucoadhesive tablets of atenolol and to optimize the drug release profile and bioadhesion. Materials and Methods: Bilayer buccal tablets of atenolol were prepared by direct compression method using simplex method of optimization to investigate the combined effect of hydroxypropyl methylcellulose 15 cps (X1), Carbopol (X2) and mannitol (X3); the in vitro drug release (Y1) and mucoadhesive strength (Y2) were taken as responses. The designed tablets were evaluated for various physical and biological parameters like drug content uniformity, in vitro drug release, short-term stability, and drug- excipient interactions (FTIR). Results: The formulation C containing hydroxypropyl methylcellulose 15 cps (10% w/w of matrix layer), Carbopol 934p (10% w/w of matrix layer) and mannitol (channeling agent, 40% w/w of matrix layer) was found to be promising. This formulation exhibited an in vitro drug release of 89.43% in 9 h along with satisfactory bioadhesion strength (7.20 g). Short-term stability studies on the promising formulation indicated that there are no significant changes in drug content and in vitro dissolution characteristics (P<0.05). IR spectroscopic studies indicated that there are no drug-excipient interactions. PMID:23071958

  10. Effect of AGM and fetal liver-derived stromal cell lines on globin expression in adult baboon (P. anubis) bone marrow-derived erythroid progenitors.

    PubMed

    Lavelle, Donald; Vaitkus, Kestutis; Ruiz, Maria Armila; Ibanez, Vinzon; Kouznetsova, Tatiana; Saunthararajah, Yogen; Mahmud, Nadim; DeSimone, Joseph

    2012-01-01

    This study was performed to investigate the hypothesis that the erythroid micro-environment plays a role in regulation of globin gene expression during adult erythroid differentiation. Adult baboon bone marrow and human cord blood CD34+ progenitors were grown in methylcellulose, liquid media, and in co-culture with stromal cell lines derived from different developmental stages in identical media supporting erythroid differentiation to examine the effect of the micro-environment on globin gene expression. Adult progenitors express high levels of γ-globin in liquid and methylcellulose media but low, physiological levels in stromal cell co-cultures. In contrast, γ-globin expression remained high in cord blood progenitors in stromal cell line co-cultures. Differences in γ-globin gene expression between adult progenitors in stromal cell line co-cultures and liquid media required cell-cell contact and were associated with differences in rate of differentiation and γ-globin promoter DNA methylation. We conclude that γ-globin expression in adult-derived erythroid cells can be influenced by the micro-environment, suggesting new potential targets for HbF induction. PMID:22693559

  11. Effect of AGM and Fetal Liver-Derived Stromal Cell Lines on Globin Expression in Adult Baboon (P. anubis) Bone Marrow-Derived Erythroid Progenitors

    PubMed Central

    Lavelle, Donald; Vaitkus, Kestutis; Ruiz, Maria Armila; Ibanez, Vinzon; Kouznetsova, Tatiana; Saunthararajah, Yogen; Mahmud, Nadim; DeSimone, Joseph

    2012-01-01

    This study was performed to investigate the hypothesis that the erythroid micro-environment plays a role in regulation of globin gene expression during adult erythroid differentiation. Adult baboon bone marrow and human cord blood CD34+ progenitors were grown in methylcellulose, liquid media, and in co-culture with stromal cell lines derived from different developmental stages in identical media supporting erythroid differentiation to examine the effect of the micro-environment on globin gene expression. Adult progenitors express high levels of γ-globin in liquid and methylcellulose media but low, physiological levels in stromal cell co-cultures. In contrast, γ-globin expression remained high in cord blood progenitors in stromal cell line co-cultures. Differences in γ-globin gene expression between adult progenitors in stromal cell line co-cultures and liquid media required cell-cell contact and were associated with differences in rate of differentiation and γ-globin promoter DNA methylation. We conclude that γ-globin expression in adult-derived erythroid cells can be influenced by the micro-environment, suggesting new potential targets for HbF induction. PMID:22693559

  12. Mechanical properties of some pigmented and unpigmented aqueous-based film coating formulations applied to aspirin tablets.

    PubMed

    Okhamafe, A O; York, P

    1986-06-01

    The Brinell hardness and Young's modulus of pigmented and unpigmented films of hydroxypropyl methylcellulose alone, and in combination with either polyethylene glycol 400 (plasticizer) or polyvinyl alcohol, which were applied to aspirin tablets, have been measured. Generally hardness and modulus data showed similar trends. The hardness and modulus of hydroxypropyl methylcellulose fell in the presence of polyethylene glycol 400 as a result of its plasticizing action. On the other hand, the hardness and modulus of the film former rose slightly when polyvinyl alcohol was initially incorporated, probably due to the crystalline phase of the additive, and then decreased when the level of the additive was further raised. Hardness and modulus were higher in films pigmented with talc than in those containing titanium dioxide because of the plate-like shape of talc and its greater interaction with the polymer systems. Some correlation was found between the Young's moduli of the applied films and those of the corresponding free films, with the moduli of the latter two 2-5 times greater. Ageing at 37 degrees C and 75% r.h. was found to cause a decrease in the mechanical properties of the unplasticized film coating systems probably as a result of decreased molecular order and enhanced polymer chain mobility. PMID:2873217

  13. Feasibility Investigation of Cellulose Polymers for Mucoadhesive Nasal Drug Delivery Applications.

    PubMed

    Hansen, Kellisa; Kim, Gwangseong; Desai, Kashappa-Goud H; Patel, Hiren; Olsen, Karl F; Curtis-Fisk, Jaime; Tocce, Elizabeth; Jordan, Susan; Schwendeman, Steven P

    2015-08-01

    The feasibility of various cellulose polymer derivatives, including methylcellulose (MC), hydroxypropyl methylcellulose (HPMC), sodium-carboxymethylcellulose (sodium-CMC), and cationic-hydroxyethylcellulose (cationic-HEC), for use as an excipient to enhance drug delivery in nasal spray formulations was investigated. Three main parameters for evaluating the polymers in nasal drug delivery applications include rheology, ciliary beat frequency (CBF), and permeation across nasal tissue. Reversible thermally induced viscosity enhancement was observed at near nasal physiological temperature when cellulose derivatives were combined with an additional excipient, poly(vinyl caprolactam)-poly(vinyl acetate)-poly(ethylene glycol) graft copolymer (PVCL-PVA-PEG). Cationic-HEC was shown to enhance acyclovir permeation across the nasal mucosa. None of the tested cellulosic polymers caused any adverse effects on porcine nasal tissues and cells, as assessed by alterations in CBF. Upon an increase in polymer concentration, a reduction in CBF was observed when ciliated cells were immersed in the polymer solution, and this decrease returned to baseline when the polymer was removed. While each cellulose derivative exhibited unique advantages for nasal drug delivery applications, none stood out on their own to improve more than one of the performance characteristics examined. Hence, these data may be useful for the development of new cellulose derivatives in nasal drug formulations. PMID:26097994

  14. [Comparison of the selected methods of cord processing for transplantation purposes].

    PubMed

    Ołdak, T; Machaj, E K; Gajkowska, A; Kruszewski, M; Kłos, M; Szczecina, R; Czajkowski, K; Kuczyńska-Sicińska, J; Pojda, Z

    2000-09-01

    Human umbilical cord blood (UCB) has been successfully used as a source of allogeneic hematopoietic cells for transplantation. Banking of the UCB requires its volume reduction to decrease storage space, costs and volume of infused DMSO. In order to select an optimal method for volume reduction we compared several methods of cord blood processing, namely buffy coat centrifugation, red cell lysis, hydroxyethyl starch (HES)-, methylcellulose- and gelatin-sedimentations. The viability of cells and the recoveries of total white blood cells, mononuclear cells and CD34+ cells was evaluated. We also compared the efficacy of red cells depletion from the original UCB sample. Buffy coat centrifugation, red cell lysis, HES, gelatin or methylcellulose resulted in high mononuclear cell recoveries, whereas high hematopoietic cell recovery was observed only after HES sedimentation and buffy coat processing. The HES sedimentation procedure compared to buffy coat processing is more time and labor consuming and resulted in higher red blood cell and platelets depletion. Both methods can be recommended as a method at choice for the umbilical cord blood processing before banking. PMID:11083012

  15. Statistical Modelling for Controlled Drug Delivery Systems and its Applications in HPMC based Hydrogels

    NASA Astrophysics Data System (ADS)

    Ghosal, Kajal; Chandra, Aniruddha

    2010-10-01

    Different concentrations of hydrophobically modified hydroxypropyl methylcellulose (HPMC, 60 M Grade) and conventional hydrophilic hydroxypropyl methylcellulose (50 cPs) were used to prepare four topical hydrogel formulations using a model non steroidal anti-inflammatory drug (NSAID) diclofenac potassium (DP). For all the formulations, suitability of different common empirical (zero-order, first-order, and Higuchi), semi-empirical (Ritger-Peppas and Peppas-Sahlin), and some new statistical (logistic, log-logistic, Weibull, Gumbel, and generalized extreme value distribution) models to describe the drug release profile were tested through non-linear least-square curve fitting. A general purpose mathematical analysis tool MATLAB is used for the purpose. Further, instead of the widely used transformed linear fit method, direct fitting was used in the paper to avoid any sort of truncation and transformation errors. The results revealed that the log-logistic distribution, among all the models that were investigated, was the best fit for hydrophobic formulations. For hydrophilic cases, the semi-empirical models and Weibull distribution worked best, although log-logistic also showed a close fit.

  16. ISL1 cardiovascular progenitor cells for cardiac repair after myocardial infarction

    PubMed Central

    Bartulos, Oscar; Zhuang, Zhen Wu; Huang, Yan; Mikush, Nicole; Suh, Carol; Bregasi, Alda; Wang, Lin; Chang, William; Krause, Diane S.; Young, Lawrence H.; Pober, Jordan S.; Qyang, Yibing

    2016-01-01

    Cardiovascular progenitor cells (CPCs) expressing the ISL1-LIM–homeodomain transcription factor contribute developmentally to cardiomyocytes in all 4 chambers of the heart. Here, we show that ISL1-CPCs can be applied to myocardial regeneration following injury. We used a rapid 3D methylcellulose approach to form murine and human ISL1-CPC spheroids that engrafted after myocardial infarction in murine hearts, where they differentiated into cardiomyocytes and endothelial cells, integrating into the myocardium and forming new blood vessels. ISL1-CPC spheroid–treated mice exhibited reduced infarct area and increased blood vessel formation compared with control animals. Moreover, left ventricular (LV) contractile function was significantly better in mice transplanted with ISL1-CPCs 4 weeks after injury than that in control animals. These results provide proof-of-concept of a cardiac repair strategy employing ISL1-CPCs that, based on our previous lineage-tracing studies, are committed to forming heart tissue, in combination with a robust methylcellulose spheroid–based delivery approach. PMID:27525311

  17. Development of bioactive coatings based on γ-irradiated proteins to preserve strawberries

    NASA Astrophysics Data System (ADS)

    Vu, K. D.; Hollingsworth, R. G.; Salmieri, S.; Takala, P. N.; Lacroix, M.

    2012-08-01

    Gamma irradiation was applied for creating cross-linked proteins to enhance the physicochemical properties of edible films made of calcium caseinate, whey protein isolate and glycerol. The characteristics of γ irradiated cross-linked proteins were analyzed by Fourier Transform Infrared spectroscopy. A second derivative spectra exhibited changes in band intensities that were correlated to an increase of β-sheet structure and a decrease of α-helix and unordered fractions of γ irradiated-cross-linked proteins as compared to the control without irradiation. Furthermore, on addition of methylcellulose to the irradiated protein matrix it was found that it has potential in enhancing the puncture strength and has no detrimental effect on water vapor permeability of protein based films. Finally, these film formulations were used as bioactive edible coatings containing natural antimicrobial agents (limonene and peppermint) to preserve the shelf life of fresh strawberries during storage. The bioactive coatings containing peppermint was found to be more efficient as preserving coatings than the formulations containing limonene. Irradiated proteins/methylcellulose/peppermint formulation had only 40% of decay at day 8 while it was 65% for the control.

  18. Development and evaluation of ethyl cellulose-based transdermal films of furosemide for improved in vitro skin permeation.

    PubMed

    Patel, Dhaval P; Setty, Chitral Mallikarjuna; Mistry, Gaurav N; Patel, Santnu L; Patel, Tarun J; Mistry, Pritesh C; Rana, Amar K; Patel, Pritesh K; Mishra, Rishabh S

    2009-01-01

    Transdermal films of the furosemide were developed employing ethyl cellulose and hydroxypropyl methylcellulose as film formers. The effect of binary mixture of polymers and penetration enhancers on physicochemical parameters including thickness, moisture content, moisture uptake, drug content, drug-polymer interaction, and in vitro permeation was evaluated. In vitro permeation study was conducted using human cadaver skin as penetration barrier in modified Keshary-Chein diffusion cell. In vitro skin permeation study showed that binary mixture, ethyl cellulose (EC)/hydroxypropyl methylcellulose (HPMC), at 8.5:1.5 ratio provided highest flux and also penetration enhancers further enhanced the permeation of drug, while propylene glycol showing higher enhancing effect compared to dimethyl sulfoxide and isopropyl myristate. Different kinetic models, used to interpret the release kinetics and mechanism, indicated that release from all formulations followed apparent zero-order kinetics and non-Fickian diffusion transport except formulation without HPMC which followed Fickian diffusion transport. Stability studies conducted as per International Conference on Harmonization guidelines did not show any degradation of drug. Based on the above observations, it can be reasonably concluded that blend of EC-HPMC polymers and propylene glycol are better suited for the development of transdermal delivery system of furosemide. PMID:19381831

  19. Polymers for use in controlled release systems: the effect of surfactants on their swelling properties.

    PubMed

    Vlachou, M; Hani, N; Efentakis, M; Tarantili, P A; Andreopoulos, A G

    2000-07-01

    The effect of an ampholytic surfactant on the swelling properties of polymeric materials was studied, using various swelling liquids. Tablets were prepared consisting of hydroxypropyl methylcellulose, poly(oxyethylene) and sodium alginate. Tego betain was the non-ionic surfactant used as an additive in a series of samples made of the above polymers. Those tablets were immersed in distilled water, phosphate buffer and 0.1 N HCl, and their weight uptake was recorded as a function of time, in order to assess the swelling process. Measurements of the contact angle of the above systems were also carried out for estimating their wetting properties. The results of this study showed a selectivity among polymers, surfactant and surrounding liquid. Clearly, an enhancement of the swelling capacity of hydroxypropyl methylcellulose tablets due to the surfactant was recorded. An unclear effect was observed in the case of poly(oxyethylene), whereas for sodium alginate, the dominant factor is its water solubility that controls swelling behaviour. PMID:10972160

  20. Influence of hydrophilic polymers on the complexation of carbamazepine with hydroxypropyl-β-cyclodextrin.

    PubMed

    Medarević, Djordje; Kachrimanis, Kyriakos; Djurić, Zorica; Ibrić, Svetlana

    2015-10-12

    In this study binary carbamazepine-hydroxypropyl-β-cyclodextrin, as well as ternary carbamazepine-hydroxypropyl-β-cyclodextrin-hydrophilic polymer systems were used to improve dissolution rate of carbamazepine. It has been shown that addition of hydrophilic polymers (Soluplus® and two types of hydroxypropyl methylcellulose-Metolose® 90SH-100 and Metolose® 65SH-1500) significantly increased solubilization capacity of hydroxypropyl-β-cyclodextrin for carbamazepine. Evaluation of carbamazepine-hydroxypropyl-β-cyclodextrin-hydrophilic polymer interactions using molecular modeling techniques showed interactions between carbamazepine, which dissociates from inclusion complexes and hydroxypropyl methylcellulose that can prevent crystallization of dissolved carbamazepine. These results can contribute to better understanding of drug-cyclodextrin-hydrophilic polymer interactions which are still not well understood. After evaluation of carbamazepine solubilization with hydroxypropyl-β-cyclodextrin and hydrophilic polymers, both binary carbamazepine-hydroxypropyl-β-cyclodextrin and ternary carbamazepine-hydroxypropyl-β-cyclodextrin-hydrophilic polymer systems were prepared by spray drying. The results of solid state characterization methods showed amorphous nature of carbamazepine in all spray dried systems, which together with the results of molecular modeling techniques indicates inclusion complex formation. Carbamazepine dissolution rate was significantly improved from spray dried formulations compared to pure drug. Binary carbamazepine-hydroxypropyl-β-cyclodextrin and ternary carbamazepine-hydroxypropyl-β-cyclodextrin-Soluplus® systems exhibited the fastest carbamazepine release, wherein the entire amount of carbamazepine was released during first 5 min. PMID:26255049

  1. Combining ibuprofen sodium with cellulosic polymers: a deep dive into mechanisms of prolonged supersaturation.

    PubMed

    Terebetski, Jenna L; Michniak-Kohn, Bozena

    2014-11-20

    The combination of a highly soluble salt form of a drug with a polymeric precipitation inhibitor has the potential to prolong drug supersaturation even following salt disproportionation. In this study, dissolution profiles of ibuprofen sodium in the presence of various cellulosic polymers, including hydroxypropyl methylcellulose (HPMC), methylcellulose (MC), and hydroxypropyl cellulose (HPC), were examined in order to assess degree and duration of supersaturation. In addition, the roles that the polymers played in altering drug solubility, media viscosity, physical form, and particle morphology were also assessed. A deep dive into the mechanisms of supersaturation revealed that intermolecular hydrogen bonding between ibuprofen and HPMC was driving supersaturation through nucleation inhibition and crystal growth modification. Polymer viscosity was proposed as the primary factor prolonging supersaturation of ibuprofen in the presence of MC, while mechanisms other than hydrogen bonding were likely to be attributed to supersaturation with the most hydrophobic polymer evaluated, HPC. Overall, the study suggested that induction of intermolecular interactions between ibuprofen and HPMC were more effective at inhibiting nucleation and maintaining prolonged supersaturation than physical modulation of solution properties, such as viscosity. PMID:25219860

  2. Pairwise polymer blends for oral drug delivery.

    PubMed

    Marks, Joyann A; Wegiel, Lindsay A; Taylor, Lynne S; Edgar, Kevin J

    2014-09-01

    Blends of polymers with complementary properties hold promise for addressing the diverse, demanding polymer performance requirements in amorphous solid dispersions (ASDs), but we lack comprehensive property understanding for blends of important ASD polymers. Herein, we prepare pairwise blends of commercially available polymers polyvinylpyrrolidone (PVP), the cationic acrylate copolymer Eudragit 100 (E100), hydroxypropyl methylcellulose acetate succinate (HPMCAS), carboxymethyl cellulose acetate butyrate (CMCAB), hydroxypropyl methylcellulose (HPMC), and the new derivative cellulose acetate adipate propionate (CAAdP). This study identifies miscible binary blends that may find use, for example, in ASDs for solubility and bioavailability enhancement of poorly water-soluble drugs. Differential scanning calorimetry, FTIR spectroscopy, and film clarity were used to determine blend miscibility. Several polymer combinations including HPMCAS/PVP, HPMC/CMCAB, and PVP/HPMC appear to be miscible in all proportions. In contrast, blends of E100/PVP and E100/HPMC showed a miscibility gap. Combinations of water-soluble and hydrophobic polymers like these may permit effective balancing of ASD performance criteria such as release rate and polymer-drug interaction to prevent nucleation and crystal growth of poorly soluble drugs. Miscible polymer combinations described herein will enable further study of their drug delivery capabilities, and provide a potentially valuable set of ASD formulation tools. PMID:24823790

  3. Zolpidem Mucoadhesive Formulations for Intranasal Delivery: Characterization, In Vitro Permeability, Pharmacokinetics, and Nasal Ciliotoxicity in Rats.

    PubMed

    Wang, Yanfeng; Li, Mi; Qian, Shuai; Zhang, Qizhi; Zhou, Limin; Zuo, Zhong; Lee, Benjamin; Toh, Melvin; Ho, Tony

    2016-09-01

    Zolpidem is a non-benzodiazepine hypnotic for the treatment of insomnia characterized by difficulties with sleep initiation. Our study aimed at developing a zolpidem mucoadhesive formulation with minimal local toxicity, prolonged nasal residence time, and enhanced absorption after intranasal delivery. In vitro permeability studies using artificial membrane and Calu-3 cell culture model indicated efficient permeability of zolpidem. Aqueous solubility of zolpidem was found to be significantly improved by hydroxypropyl-β-cyclodextrin. Various mucoadhesive formulations were then prepared comprising zolpidem, hydroxypropyl-β-cyclodextrin, and mucoadhesive polymers such as hydroxypropyl methylcellulose, sodium carboxymethylcellulose, and sodium alginate. Pharmacokinetic studies in rats demonstrated that intranasally administered zolpidem could achieve significantly faster absorption rate and higher plasma concentration than that from oral route. In comparison with solution formulation (ZLP-S03), the optimized mucoadhesive formulation (ZLP-B01) containing 0.25% hydroxypropyl methylcellulose was found to improve Cmax from 352.6 ± 86.0 to 555.7 ± 175.8 ng/mL, and AUC0-inf from 32,890 ± 7547 to 65,447 ± 36,996 ng·min/mL with mild nasal ciliotoxicity in rats. PMID:27189774

  4. Cytotoxicity of Different Excipients on RPMI 2650 Human Nasal Epithelial Cells.

    PubMed

    Horváth, Tamás; Bartos, Csilla; Bocsik, Alexandra; Kiss, Lóránd; Veszelka, Szilvia; Deli, Mária A; Újhelyi, Gabriella; Szabó-Révész, Piroska; Ambrus, Rita

    2016-01-01

    The nasal route receives a great deal of attention as a non-invasive method for the systemic administration of drugs. For nasal delivery, specific formulations containing excipients are used. Because of the sensitive respiratory mucosa, not only the active ingredients, but also additives need to be tested in appropriate models for toxicity. The aim of the study was to measure the cytotoxicity of six pharmaceutical excipients, which could help to reach larger residence time, better permeability, and increased solubility dissolution rate. The following excipients were investigated on RPMI 2650 human nasal septum tumor epithelial cells: β-d-mannitol, sodium hyaluronate, α and β-cyclodextrin, polyvinyl alcohol and methylcellulose. 3-(4,5-dimethyltiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) dye conversion assay and real-time impedance analysis were used to investigate cytotoxicity. No excipient showed toxicity at 0.3% (w/v) concentration or below while 1% concentration a significantly reduced metabolic activity was measured by MTT assay for methylcellulose and cyclodextrins. Using impedance measurements, only β-cyclodextrin (1%) was toxic to cells. Mannitol at 1% concentration had a barrier opening effect on epithelial cells, but caused no cellular damage. Based on the results, all additives at 0.3%, sodium hyaluronate and polyvinyl alcohol at 1% concentrations can be safely used for nasal formulations. PMID:27213303

  5. In Vitro Colony Assays for Characterizing Tri-potent Progenitor Cells Isolated from the Adult Murine Pancreas.

    PubMed

    Tremblay, Jacob R; LeBon, Jeanne M; Luo, Angela; Quijano, Janine C; Wedeken, Lena; Jou, Kevin; Riggs, Arthur D; Tirrell, David A; Ku, H Teresa

    2016-01-01

    Stem and progenitor cells from the adult pancreas could be a potential source of therapeutic beta-like cells for treating patients with type 1 diabetes. However, it is still unknown whether stem and progenitor cells exist in the adult pancreas. Research strategies using cre-lox lineage-tracing in adult mice have yielded results that either support or refute the idea that beta cells can be generated from the ducts, the presumed location where adult pancreatic progenitors may reside. These in vivo cre-lox lineage-tracing methods, however, cannot answer the questions of self-renewal and multi-lineage differentiation-two criteria necessary to define a stem cell. To begin addressing this technical gap, we devised 3-dimensional colony assays for pancreatic progenitors. Soon after our initial publication, other laboratories independently developed a similar, but not identical, method called the organoid assay. Compared to the organoid assay, our method employs methylcellulose, which forms viscous solutions that allow the inclusion of extracellular matrix proteins at low concentrations. The methylcellulose-containing assays permit easier detection and analyses of progenitor cells at the single-cell level, which are critical when progenitors constitute a small sub-population, as is the case for many adult organ stem cells. Together, results from several laboratories demonstrate in vitro self-renewal and multi-lineage differentiation of pancreatic progenitor-like cells from mice. The current protocols describe two methylcellulose-based colony assays to characterize mouse pancreatic progenitors; one contains a commercial preparation of murine extracellular matrix proteins and the other an artificial extracellular matrix protein known as a laminin hydrogel. The techniques shown here are 1) dissociation of the pancreas and sorting of CD133(+)Sox9/EGFP(+) ductal cells from adult mice, 2) single cell manipulation of the sorted cells, 3) single colony analyses using microfluidic q

  6. Core-in-cup tablet design of metoprolol succinate and its evaluation for controlled release.

    PubMed

    Nagaraju, Ravouru; Meera, Durgumahanthi Sai; Kaza, Rajesh; Arvind, Vakati Venkata; Venkateswarlu, Vobalaboina

    2009-12-01

    The core-in-cup matrix tablets of Metoprolol succinate were prepared by wet granulation technique. Of all the investigated formulations, the optimized formulation of MS-09 followed zero-order kinetics of drug release. Trail on MS-09 was formulated using 7.5% hydrogenated castor-oil (HCO) and 4% of hydroxyl propyl methylcellulose (HPMC K15M) with an objective to achieve a linear release profile for 24 h. There is no initial burst release, with 16.17% of drug released during the first hour and release was extended up to 24 hrs. Study of drug release kinetics was performed by application of dissolution data to various kinetic equations like zero-order; first order, Higuchi and Korsmeyer-Peppas, from R(2) value (0.9975) it was concluded that the drug release followed zero order kinetics with both erosion and diffusion as the release mechanisms. PMID:20025598

  7. Preparation and evaluation of gastroretentive floating tablets of acyclovir.

    PubMed

    Garg, Rajeev; Gupta, G D

    2009-10-01

    The present study performed by preparation and evaluation of floating tablets of Acyclovir as model drug for prolongation of gastric residence time. Floating effervescent tablets were formulated by various materials like hydroxypropyl methylcellulose K 4M, K 15M, psyllium husk, swelling agent as crospovidone and microcrystalline cellulose and gas generating agent like sodium bicarbonate and citric acid and evaluated for floating properties, swelling characteristics and in vitro drug release studies. Floating noneffervescent tablets were prepared by polypropylene foam powder and different matrix forming polymers like HPMC K 4M, Carbopol 934P, xanthan gum and sodium alginate. In vitro drug release studies were performed and drug release kinetics evaluated using the linear regression method was found to follow both the Higuchi and the Korsmeyer and Peppas equation. The drug release mechanism was found fickian type in most of the formulations. PMID:19751200

  8. Development and Evaluation of Sustained Release Tablet of Betahistine Hydrochloride Using Ion Exchange Resin Tulsion T344

    PubMed Central

    Wagh, Vijay D.; Pawar, Nilesh

    2012-01-01

    An attempt was made to sustain the release of Betahistine hydrochloride by complexation technique using strong cation-exchange resin, Tulsion T344. The drug loading onto ion-exchange resin was optimized for mixing time, activation, effect of pH, swelling time, ratio of drug : resin, and temperature. The resinate was evaluated for micromeritic properties and characterized using XRPD and IR. For resinate sustained release tablets were formulated using hydoxypropyl methylcellulose K100M. The tablets were evaluated for hardness, thickness, friability, drug content, weight variation, and in vitro drug release. Tablets thus formulated (Batch T-3) provided sustained release of drug over a period of 12 h. The release of Betahistine HCl from resinate controls the diffusion of drug molecules through the polymeric material into aqueous medium. Results showed that Betahistine HCl was formulated into a sustained dosage form as an alternative to the conventional tablet. PMID:22779010

  9. Flexible and printable paper-based strain sensors for wearable and large-area green electronics.

    PubMed

    Liao, Xinqin; Zhang, Zheng; Liao, Qingliang; Liang, Qijie; Ou, Yang; Xu, Minxuan; Li, Minghua; Zhang, Guangjie; Zhang, Yue

    2016-07-14

    Paper-based (PB) green electronics is an emerging and potentially game-changing technology due to ease of recycling/disposal, the economics of manufacture and the applicability to flexible electronics. Herein, new-type printable PB strain sensors (PPBSSs) from graphite glue (graphite powder and methylcellulose) have been fabricated. The graphite glue is exposed to thermal annealing to produce surface micro/nano cracks, which are very sensitive to compressive or tensile strain. The devices exhibit a gauge factor of 804.9, response time of 19.6 ms and strain resolution of 0.038%, all performance indicators attaining and even surpassing most of the recently reported strain sensors. Due to the distinctive sensing properties, flexibility and robustness, the PPBSSs are suitable for monitoring of diverse conditions such as structural strain, vibrational motion, human muscular movements and visual control. PMID:27314505

  10. Effect of gamma irradiation on HPMC/ZnO nanocomposite films

    NASA Astrophysics Data System (ADS)

    Rao, B. Lakshmeesha; Asha, S.; Madhukumar, R.; Latha, S.; Gowda, Mahadeva; Shetty, G. Rajesha; Shivananda, C. S.; Harish, K. V.; Sangappa

    2015-06-01

    The present work looks into the structural and mechanical properties modification in ZnO nanoparticle incorporated Hydroxypropyl methylcellulose (HPMC) polymer films, induced by gamma irradiation. The irradiation process was performed in gamma chamber at room temperature by use of Cobalt-60 source (Average energy of 1.25MeV) at different doses: 0, 50, 100, 150 and 200 kGy respectively. The changes in structural parameters and mechanical properties in pure and gamma irradiated HPMC/ZnO nanocomposite films have been studied using X-ray scattering (XRD) data and universal testing machine (UTM). It is found that gamma irradiation decreases the structural parameters and improves the mechanical properties of nanocomposite films.

  11. Shear and extensional properties of kefiran.

    PubMed

    Piermaría, Judith; Bengoechea, Carlos; Abraham, Analía Graciela; Guerrero, Antonio

    2016-11-01

    Kefiran is a neutral polysaccharide constituted by glucose and galactose produced by Lactobacillus kefiranofaciens. It is included into kefir grains and has several health promoting properties. In the present work, shear and extensional properties of different kefiran aqueous dispersions (0.5, 1 and 2% wt.) were assessed and compared to other neutral gums commonly used in food, cosmetic and pharmaceutics industries (methylcellulose, locust bean gum and guar gum). Kefiran showed shear flow characteristics similar to that displayed by other representative neutral gums, although it always yielded lower viscosities at a given concentration. For each gum system it was possible to find a correlation between dynamic and steady shear properties by a master curve including both the apparent and complex viscosities. When studying extensional properties of selected gums at 2% wt. by means of a capillary break-up rheometer, kefiran solutions did not show important extensional properties, displaying a behaviour close the Newtonian. PMID:27516254

  12. Compressive Strength, Chloride Permeability, and Freeze-Thaw Resistance of MWNT Concretes under Different Chemical Treatments

    PubMed Central

    Wang, Xingang; Wang, Yao; Xi, Yunping

    2014-01-01

    This study investigated compressive strength, chloride penetration, and freeze-thaw resistance of multiwalled carbon nanotube (MWNT) concrete. More than 100 cylindrical specimens were used to assess test variables during sensitivity observations, including water-cement ratios (0.75, 0.5, and 0.4) and exposure to chemical agents (including gum arabic, propanol, ethanol, sodium polyacrylate, methylcellulose, sodium dodecyl sulfate, and silane). To determine the adequate sonication time for MWNT dispersal in water, the compressive strengths of MWNT concrete cylinders were measured after sonication times ranging from 2 to 24 minutes. The results demonstrated that the addition of MWNT can increase the compressive strength of concrete by up to 108%. However, without chemical treatment, MWNT concretes tend to have poor freeze-thaw resistance. Among the different chemical treatments, MWNT concrete treated with sodium polyacrylate has the best compressive strength, chloride resistance, and freeze-thaw durability. PMID:25140336

  13. Effect of gamma irradiation on HPMC/ZnO nanocomposite films

    SciTech Connect

    Rao, B. Lakshmeesha; Asha, S.; Madhukumar, R.; Latha, S.; Gowda, Mahadeva; Shivananda, C. S.; Harish, K. V.; Sangappa; Shetty, G. Rajesha

    2015-06-24

    The present work looks into the structural and mechanical properties modification in ZnO nanoparticle incorporated Hydroxypropyl methylcellulose (HPMC) polymer films, induced by gamma irradiation. The irradiation process was performed in gamma chamber at room temperature by use of Cobalt-60 source (Average energy of 1.25MeV) at different doses: 0, 50, 100, 150 and 200 kGy respectively. The changes in structural parameters and mechanical properties in pure and gamma irradiated HPMC/ZnO nanocomposite films have been studied using X-ray scattering (XRD) data and universal testing machine (UTM). It is found that gamma irradiation decreases the structural parameters and improves the mechanical properties of nanocomposite films.

  14. Formulation Development and Evaluation of Fast Dissolving Film of Telmisartan

    PubMed Central

    Londhe, Vaishali Y.; Umalkar, Kashmira B.

    2012-01-01

    Hypertension is a major cause of concern not just in the elderly but also in the youngsters. An effort was made to formulate a fast dissolving film containing telmisartan which is used in the treatment of hypertension with a view to improve the onset of action, therapeutic efficacy, patient compliance and convenience. The major challenge in formulation of oral films of telmisatran is that it shows very less solubility in the pH range of 3–9. Various film forming agents and polyhydric alcohols were evaluated for optimizing composition of fast dissolving films. Fast dissolving films using hydroxypropyl methylcellulose, polyvinyl alcohol, glycerol, sorbitol, menthol and an alkalizer were formulated using solvent casting method. Optimized formulations were evaluated for their weight, thickness, folding endurance, appearance, tensile strength, disintegration time and dissolution profile. PMID:23325992

  15. Roller compactor: The effect of mechanical properties of primary particles.

    PubMed

    Al-Asady, Riyadh B; Osborne, James D; Hounslow, Michael J; Salman, Agba D

    2015-12-30

    In this study, the nano-indentation hardness of a single primary particle was measured for six different materials; microcrystalline cellulose, hydroxypropyl methylcellulose, maltodextrin, lactose, sodium carbonate and calcium carbonate. This was linked to the properties of the ribbons produced by roller compactor at different hydraulic pressures in the range of 30-230 bar. The main investigated ribbon properties were strength, porosity and width. For the range of materials that were tested, it was found that the lower the nano-indentation hardness of the powder particles, the higher the strength, width and lower the ribbon porosity. This is because the applied pressure by the rollers was enough to plastically deform the particles and create bonds between them. A method was suggested to predict the workability of the powder in roller compactor by using the data of nano-indentation for three materials. PMID:26024822

  16. Developing dissolution testing methodologies for extended-release oral dosage forms with supersaturating properties. Case example: Solid dispersion matrix of indomethacin.

    PubMed

    Tajiri, Tomokazu; Morita, Shigeaki; Sakamoto, Ryosaku; Mimura, Hisahi; Ozaki, Yukihiro; Reppas, Christos; Kitamura, Satoshi

    2015-07-25

    The objective of this study was to develop an in vitro dissolution test method with discrimination ability for an extended-release solid dispersion matrix of a lipophilic drug using the United States Pharmacopeia (USP) Apparatus 4, flow-through cell apparatus. In the open-loop configuration, the sink condition was maintained by manipulating the flow rate of the dissolution medium. To evaluate the testing conditions, the drug release mechanism from an extended-release solid dispersion matrix containing hydrophobic and hydrophilic polymers was investigated. As the hydroxypropyl methylcellulose (HPMC) maintained concentrations of indomethacin higher than the solubility in a dissolution medium, the release of HPMC into the dissolution medium was also quantified using size-exclusion chromatography. We concluded that the USP Apparatus 4 is suitable for application to an in vitro dissolution method for orally administered extended-release solid dispersion matrix formulations containing poorly water-soluble drugs. PMID:26022889

  17. Preparation and characterization of methacrylate hydrogels for zeta potential control

    NASA Technical Reports Server (NTRS)

    Gregonis, D. E.; Ma, S. M.; Vanwagenen, R.; Andrade, J. D.

    1976-01-01

    A technique based on the measurement of streaming potentials has been developed to evaluate the effects of hydrophilic coatings on electroosmotic flow. The apparatus and procedure are described as well as some results concerning the electrokinetic potential of glass capillaries as a function of ionic strength, pH, and temperature. The effect that turbulence and entrance flow conditions have on accurate streaming potential measurements is discussed. Various silane adhesion promoters exhibited only a slight decrease in streaming potential. A coating utilizing a glycidoxy silane base upon which methylcellulose is applied affords a six-fold decrease over uncoated tubes. Hydrophilic methacrylate gels show similar streaming potential behavior, independent of the water content of the gel. By introduction of positive or negative groups into the hydrophilic methacrylate gels, a range of streaming potential values are obtained having absolute positive or negative signs.

  18. Formulation development and evaluation of fast dissolving film of telmisartan.

    PubMed

    Londhe, Vaishali Y; Umalkar, Kashmira B

    2012-03-01

    Hypertension is a major cause of concern not just in the elderly but also in the youngsters. An effort was made to formulate a fast dissolving film containing telmisartan which is used in the treatment of hypertension with a view to improve the onset of action, therapeutic efficacy, patient compliance and convenience. The major challenge in formulation of oral films of telmisatran is that it shows very less solubility in the pH range of 3-9. Various film forming agents and polyhydric alcohols were evaluated for optimizing composition of fast dissolving films. Fast dissolving films using hydroxypropyl methylcellulose, polyvinyl alcohol, glycerol, sorbitol, menthol and an alkalizer were formulated using solvent casting method. Optimized formulations were evaluated for their weight, thickness, folding endurance, appearance, tensile strength, disintegration time and dissolution profile. PMID:23325992

  19. Development of novel guava puree films containing chitosan nanoparticles.

    PubMed

    Lorevice, Marcos V; de Moura, Márcia R; Aouada, Fauze A; Mattoso, Luiz H C

    2012-03-01

    One of the overall goals of industries is to use packages that do not cause environmental problems at disposal time, but that have the same properties as the conventional ones. The goal of this study is to synthesize edible films based on hydroxypropyl methylcellulose (HPMC) with guava puree and chitosan (CS) nanoparticles. This was divided into two stages, the first is the synthesis of chitosan nanoparticles and the second is the production of the films. For the nanoparticles, average size and zeta potential measurements were performed. The characterizations of mechanical and thermal properties, solubility and water vapor permeability tests were conducted in the films. It was observed that when the nanoparticles were added to HPMC and guava puree films, they improved their mechanical and thermal properties, as well as decreased the films solubility and permeability. The potential application of the films prepared would be in edible films with flavor and odor to extend the shelf life of products. PMID:22755113

  20. Moisture permeability mechanisms of some aqueous-based tablet film coatings containing soluble additives.

    PubMed

    Okhamafe, A O; Iwebor, H U

    1987-09-01

    Moisture permeation parameters--diffusion, solubility and permeation coefficients--for hydroxypropyl methylcellulose (HPMC) and partially hydrolyzed polyvinyl alcohol (PVA) films containing either of two water-soluble additives (citric acid and urea) have been evaluated from transmission and time lag data. Contrary to expectations, the moisture diffusivities of the films were markedly lowered by the presence of these additives. However, the solubility coefficients increased while the permeability coefficients were largely unchanged up to 10 wt% of the additives. A complex phenomenon involving an extensive interlacing network of mainly hydrogen bond interactions between additive and films former was believed to influence the permeation properties of the films. The estimated limits of compatibility of the additives with the film-former were in the range of 5-10 wt%. PMID:3432347

  1. Compressive strength, chloride permeability, and freeze-thaw resistance of MWNT concretes under different chemical treatments.

    PubMed

    Wang, Xingang; Rhee, Inkyu; Wang, Yao; Xi, Yunping

    2014-01-01

    This study investigated compressive strength, chloride penetration, and freeze-thaw resistance of multiwalled carbon nanotube (MWNT) concrete. More than 100 cylindrical specimens were used to assess test variables during sensitivity observations, including water-cement ratios (0.75, 0.5, and 0.4) and exposure to chemical agents (including gum arabic, propanol, ethanol, sodium polyacrylate, methylcellulose, sodium dodecyl sulfate, and silane). To determine the adequate sonication time for MWNT dispersal in water, the compressive strengths of MWNT concrete cylinders were measured after sonication times ranging from 2 to 24 minutes. The results demonstrated that the addition of MWNT can increase the compressive strength of concrete by up to 108%. However, without chemical treatment, MWNT concretes tend to have poor freeze-thaw resistance. Among the different chemical treatments, MWNT concrete treated with sodium polyacrylate has the best compressive strength, chloride resistance, and freeze-thaw durability. PMID:25140336

  2. In vitro evaluation of porous carrier-based floating granular delivery system of orlistat.

    PubMed

    Jain, Sunil K; Agrawal, G P; Jain, N K

    2008-01-01

    The purpose of the study is to prepare and evaluate an intragastric floating granular delivery system of orlistat using (i) calcium silicate as porous carrier; and (ii) hydroxypropyl methylcellulose K4M, ethyl cellulose, and Carbopol 940 as matrix-forming polymers. The effect of various formulation and process variables on the micro-meritic properties, in vitro floating behavior, percent drug content, and in vitro drug release was studied. The release mechanism of orlistat from these granules was evaluated on the basis of various theoretical equations. The optimized formulation demonstrated favorable in vitro floating and release characteristics. The release pattern of optimized, secondary-coated granules of orlistat in simulated gastrointestinal fluids corresponded best to the Peppas-Korsmeyer model and Higuchi matrix model. The results clearly indicated the controlled and sustained release of orlistat from its gastro-retentive floating granular delivery system. PMID:19174957

  3. Using white sorghum flour for gluten-free breadmaking.

    PubMed

    Velázquez, Noemí; Sánchez, Hugo; Osella, Carlos; Santiago, Liliana G

    2012-06-01

    Cornstarch/sorghum flour (X₁) ratio, water added (X₂) and amount of hydroxypropyl methylcellulose (HPMC) used (X₃) were varied for making gluten-free bread so as to optimize batter softness (Y₁), specific volume (Y₂) and crumb grain (Y₃). A second-order model was employed to generate a response surface. It was found that the softness of the batter depends significantly on three factors in a linear way. The specific volume (Y₂), in particular, was increased significantly with the increment of X₁ and X₃. The crumb grain (Y₃) depended significantly on three factors, its scores increased with X₁ and decreased with the water added (X₂). Finally, 0.55 cornstarch/sorghum flour ratio, 90% of water added and 3% of HPMC were chosen as the best conditions, considering acceptable levels of specific volume and of crumb grain, and also taking into account the possibility of using the highest proportion of sorghum flour. PMID:22111686

  4. Baking loss of bread with special emphasis on increasing water holding capacity.

    PubMed

    Kotoki, D; Deka, S C

    2010-01-01

    Potato flour (PF), hydroxypropyl methylcellulose (HPMC) and honey were used as baking agents and their effects on baking loss and sensory quality were studied. PF at 1, 2 and 4% levels decreased baking loss followed by HPMC and honey. Water absorption was substantially high with the HPMC (70.8-80.8%) and PF (61.7-71.7%) compared to honey and normal standard bread. PF incorporation increased shelf-life (6-7 days) as compared to HPMC and honey. HPMC incorporated bread had higher moisture content (36.8-38.0%) followed by PF (34.5-35.8%) and honey (34.7%). The ash content was in the order of PF (1%) > honey (4%) > PF (2%) > normal bread > HPMC (0.5 g) > PF (4%) > HPMC (1 g) > HPMC (1.5 g). PF incorporated bread had sensorily highest acceptance followed by HPMC and honey. PMID:23572615

  5. Albizia procera gum as an excipient for oral controlled release matrix tablet.

    PubMed

    Pachuau, Lalduhsanga; Mazumder, Bhaskar

    2012-09-01

    The purpose of this research was to develop and evaluate controlled release matrix tablets of paracetamol based on natural gum exudates of Albizia procera. Procera gum was characterized of its properties like compressibility index, angle of repose, viscosity and moisture content. The interaction between the gum and paracetamol was also studied through differential scanning calorimetry (DSC) and FTIR spectroscopy. Matrix tablets were then prepared by wet granulation method with different concentrations of procera gum and hydroxypropyl methylcellulose (HPMC) and evaluated for their physical properties like weight variation, hardness, friability and content uniformity. Dissolution study was conducted to characterize release mechanism from the matrix system and data were fitted to various kinetic models. The mechanism of drug release from both types of matrix tablets was found to be anomalous type. Results from various evaluations suggested that A. procera gum could be used as drug release retardant in controlled release matrix systems. PMID:24751043

  6. Electrophoresis experiment for space

    NASA Technical Reports Server (NTRS)

    Vanderhoff, J. W.; Micale, F. J.

    1976-01-01

    The Apollo 16 electrophoresis experiment was analyzed, demonstrating that the separation of the two different-size monodisperse latexes did indeed take place, but that the separation was obscured by the pronounced electroosmotic flow of the liquid medium. The results of this experiment, however, were dramatic since it is impossible to carry out a similar separation on earth. It can be stated unequivocally from this experiment that any electrophoretic separation will be enhanced under microgravity conditions. The only question is the degree of this enhancement, which can be expected to vary from one experimental technique to another. The low-electroosmotic-mobility coating (Z6040-MC) developed under this program was found to be suitable for a free-fluid electrophoretic separation such as the experiment designed for the ASTP flight. The problem with this coating, however, is that its permanency is limited because of the slow desorption of the methylcellulose from the coated surface.

  7. Microwave assisted synthesis of acrylamide grafted locust bean gum and its application in drug delivery.

    PubMed

    Kaity, Santanu; Isaac, Jinu; Kumar, P Mahesh; Bose, Anirbandeep; Wong, Tin Wui; Ghosh, Animesh

    2013-10-15

    Acrylamide grafted copolymer of locust bean gum was prepared by microwave irradiation using ceric ammonium nitrate as redox initiator. The grafting process was optimized in terms of irradiation time, amount of initiator and acrylamide by using constant amount of native locust bean gum. The grafted gum was characterized by Fourier transform infrared spectroscopy (FT-IR), (13)C nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), X-ray diffraction study (XRD), differential scanning calorimetry (DSC), elemental analysis, contact angle, viscosity, molecular weight, swelling and biodegradability studies. The grafted gum was found to be biodegradable and non-toxic. It was further used to prepare controlled-release matrix tablet of buflomedil hydrochloride. The in vitro release profile of the tablet showed the rate controlling property of acrylamide grafted locust bean gum was similar to that of hydroxypropyl methylcellulose (HPMC-K15M). PMID:23987450

  8. Detection of pharmaceutical crystals in polymer particles by transmission electron microscopy

    NASA Astrophysics Data System (ADS)

    Ricarte, Ralm; Hillmyer, Marc; Lodge, Timothy

    2015-03-01

    The use of solid dispersions, blends of an active pharmaceutical ingredient (API) and a polymer excipient, may significantly enhance the dissolution performance of a poorly water soluble drug. However, the polymer's role in inhibiting API crystallization within the solid dispersion is not well understood. One of the main challenges in elucidating this mechanism is the difficulty of detecting small amounts of API crystals (less than 5 volume percent) within the polymer matrix. In this work, we explore the use of transmission electron microscopy (TEM) to characterize the crystallinity of griseofulvin (GF) in hydroxypropyl methylcellulose acetate succinate (HPMCAS) solid dispersions. Using both real-space images and electron diffraction patterns from TEM, GF crystals in the HPMCAS matrix were unambiguously identified with nanometer resolution and with a crystal detection sensitivity superior to both wide-angle X-ray scattering and differential scanning calorimetry. TEM shows great potential for characterizing even trace API crystallinity in solid polymeric dispersions.

  9. Antioxidant films based on cross-linked methyl cellulose and native Chilean berry for food packaging applications.

    PubMed

    López de Dicastillo, Carol; Rodríguez, Francisco; Guarda, Abel; Galotto, Maria José

    2016-01-20

    Development of antioxidant and antimicrobial active food packaging materials based on biodegradable polymer and natural plant extracts has numerous advantages as reduction of synthetic additives into the food, reduction of plastic waste, and food protection against microorganisms and oxidation reactions. In this way, active films based on methylcellulose (MC) and maqui (Aristotelia chilensis) berry fruit extract, as a source of antioxidants agents, were studied. On the other hand, due to the high water affinity of MC, this polymer was firstly cross-linked with glutaraldehyde (GA) at different concentrations. The results showed that the addition of GA decreased water solubility, swelling, water vapor permeability of MC films, and the release of antioxidant substances from the active materials increased with the concentration of GA. Natural extract and active cross-linked films were characterized in order to obtain the optimal formulation with the highest antioxidant activity and the best physical properties for latter active food packaging application. PMID:26572446

  10. Development and evaluation of sustained release tablet of betahistine hydrochloride using ion exchange resin tulsion t344.

    PubMed

    Wagh, Vijay D; Pawar, Nilesh

    2012-01-01

    An attempt was made to sustain the release of Betahistine hydrochloride by complexation technique using strong cation-exchange resin, Tulsion T344. The drug loading onto ion-exchange resin was optimized for mixing time, activation, effect of pH, swelling time, ratio of drug : resin, and temperature. The resinate was evaluated for micromeritic properties and characterized using XRPD and IR. For resinate sustained release tablets were formulated using hydoxypropyl methylcellulose K100M. The tablets were evaluated for hardness, thickness, friability, drug content, weight variation, and in vitro drug release. Tablets thus formulated (Batch T-3) provided sustained release of drug over a period of 12 h. The release of Betahistine HCl from resinate controls the diffusion of drug molecules through the polymeric material into aqueous medium. Results showed that Betahistine HCl was formulated into a sustained dosage form as an alternative to the conventional tablet. PMID:22779010

  11. Online preconcentration by transient isotachophoresis in linear polymer on a poly(methyl methacrylate) microchip for separation of human serum albumin immunoassay mixtures.

    PubMed

    Mohamadi, Mohamad Reza; Kaji, Noritada; Tokeshi, Manabu; Baba, Yoshinobu

    2007-05-15

    Online preconcentration of human serum albumin (HSA) and its immunocomplex with a monoclonal antibody by on-chip transient isotachophoresis is reported. An 800-fold signal enhancement was achieved following the preconcentration on standard cross-channel microchips made of poly (methyl methacrylate). Sample injection, preconcentration, and separation were done continuously and controlled solely by a sequential voltage switching program. The preconcentration was followed by on-chip nondenaturing gel electrophoresis in methylcellulose solution. The method was applied to microchip electrophoresis immunoassay of HSA. Baseline separation of HSA and its immunocomplex was achieved in 25 s in the first 1 cm of the microchannel. In a direct immunoassay, the minimum detectable concentration of fluorescent labeled HSA by laser-induced fluorescence detection was 7.5 pM. PMID:17437335

  12. A novel once daily microparticulate dosage form comprising lansoprazole to prevent nocturnal acid breakthrough in the case of gastro-esophageal reflux disease: preparation, pharmacokinetic and pharmacodynamic evaluation.

    PubMed

    Alai, Milind; Lin, Wen Jen

    2013-01-01

    The objective of this study was to formulate and evaluate the lansoprazole (LPZ)-loaded microparticles to prevent nocturnal acid breakthrough in the case of gastro-esophageal reflux disease (GERD). The microparticulate delivery system was prepared by solvent evaporation method using Eudragit RS100 as a matrix polymer followed by enteric coated with Eudragit S100 and hydroxypropyl methylcellulose phthalate HP55 using spray drying method. The enteric coated microparticles were stable in gastric pH condition. In vivo pharmacokinetic and pharmacodynamic studies in male Wistar rats demonstrated that enteric coated microparticles sustained release of LPZ and promoted ulcer healing activity. In other words, the microparticulate dosage form provided effective drug concentration for a longer period as compared to conventional extended release dosage form, and showed sufficient anti-acid secretion activity to treat acid related disorders including the enrichment of nocturnal acid breakthrough event based on a once daily administration. PMID:23294453

  13. Microencapsulation of Lactobacillus acidophilus NCIMB 701748 in matrices containing soluble fibre by spray drying: Technological characterization, storage stability and survival after in vitro digestion☆

    PubMed Central

    Yonekura, Lina; Sun, Han; Soukoulis, Christos; Fisk, Ian

    2014-01-01

    We evaluated sodium alginate, chitosan and hydroxypropyl methylcellulose (HPMC) as co-encapsulants for spray dried Lactobacillus acidophilus NCIMB 701748 by assessing their impact on cell viability and physicochemical properties of the dried powders, viability over 35 days of storage at 25 °C and survival after simulated digestion. Fibres were added to a control carrier medium containing whey protein concentrate, d-glucose and maltodextrin. Sodium alginate and HPMC did not affect cell viability but chitosan reduced viable counts in spray dried powders, as compared to the control. Although chitosan caused large losses of viability during spray-drying, these losses were counteracted by the excellent storage stability compared to control, sodium alginate and HPMC, and the overall effect became positive after the 35-day storage. Chitosan also improved survival rates in simulated GI conditions, however no single fibre could improve L. acidophilus NCIMB 701748 viability in all steps from production through storage and digestion. PMID:24748900

  14. Modulation of distal colonic epithelial barrier function by dietary fibre in normal rats

    PubMed Central

    Mariadason, J; Catto-Smith, A; Gibson, P

    1999-01-01

    BACKGROUND—Dietary fibre influences the turnover and differentiation of the colonic epithelium, but its effects on barrier function are unknown. 
AIMS—To determine whether altering the type and amount of fibre in the diet affects paracellular permeability of intestinal epithelium, and to identify the mechanisms of action. 
METHODS—Rats were fed isoenergetic low fibre diets with or without supplements of wheat bran (10%) or methylcellulose (10%), for four weeks. Paracellular permeability was determined by measurement of conductance and 51Cr-EDTA flux across tissue mounted in Ussing chambers. Faecal short chain fatty acid (SCFA) concentrations were assessed by gas chromatography, epithelial kinetics stathmokinetically, and mucosal brush border hydrolase activities spectrophotometrically. 
RESULTS—Body weight was similar across the dietary groups. Conductance and 51Cr-EDTA flux were approximately 25% higher in animals fed no fibre, compared with those fed wheat bran or methylcellulose in the distal colon, but not in the caecum or jejunum. Histologically, there was no evidence of epithelial injury or erosion associated with any diet. The fibres exerted different spectra of effects on luminal SCFA concentrations and pH, and on mucosal indexes, but both bulked the faeces, were trophic to the epithelium, and stimulated expression of a marker of epithelial differentiation. 
CONCLUSIONS—Both a fermentable and a non-fermentable fibre reduce paracellular permeability specifically in the distal colon, possibly by promoting epithelial cell differentiation. The mechanisms by which the two fibres exert their effects are likely to be different. 

 Keywords: colon; differentiation; epithelium; fibre; paracellular permeability; proliferation PMID:10026327

  15. Evaluation of Phosphorylated Psyllium Seed Polysaccharide as a Release Retardant

    PubMed Central

    Rao, Monica R. P.; Warrier, Deepa U.; Rao, Shivani H.

    2015-01-01

    The aim of the present study was to modify psyllium seed polysaccharide and evaluate the modified polysaccharide as release retardant in tablets employing ciprofloxacin hydrochloride as model drug. Studies on polysaccharide from psyllium husk has been reported but no work has been reported on characterization and modification of the polysaccharide present in the psyllium (Plantago ovata) seed and the use of the modified polysaccharide as a release retardant in tablets. In this study, the seed gum was modified using sodium trimetaphosphate as crosslinking agent. Sustained release matrix tablets of ciprofloxacin hydrochloride were prepared by wet granulation using various drug-polymer ratios. The polymers investigated were psyllium polysaccharide, phosphorylated psyllium polysaccharide and widely used release retardant hydroxypropyl methylcellulose K100M. The tablets were evaluated for hardness, friability, drug content, swelling profile and in vitro dissolution studies. The matrix tablets containing 1:3 proportion of drug-phosphorylated psyllium polysaccharide was found to have higher hardness as compared to tablets containing 1:1 and 1:2 proportions. The results of swelling behavior in water showed that the tablets containing 1:3 drug:phosphorylated psyllium polysaccharide ratio had swelling comparable to that of tablets containing 1:3 drug:hydroxypropyl methylcellulose ratio. The in vitro dissolution studies shows that the dissolution rate was retarded from 98.41 to 37.6% in 6 h with increase in concentration of phosphorylated psyllium polysaccharide from 100 to 300 mg. Formulations containing psyllium polysaccharide showed complete drug release in 8 h whereas those formulated with phosphorylated psyllium polysaccharide exhibited extended drug release over the 12 h period. Drug release kinetic studies revealed that drug release followed Korsmeyer-Peppas model. PMID:26798177

  16. Long-term Stability of Zonisamide, Amitriptyline, and Glycopyrrolate in Extemporaneously Prepared Liquid-dosage Forms at Two Temperatures.

    PubMed

    Nahata, Milap C

    2016-01-01

    The lack of commercially available liquid dosage forms for pediatric patients prompted this study. The objectives of our study were to determine the stability of zonisamide, amitriptyline, and glycopyrrolate in extemporaneously prepared oral suspensions in plastic prescription bottles. One group of suspensions was prepared in OraPlus:OraSweet (1:1) for each drug and stored either under refrigeration (4°C) or at room temperature (25°C). A second group of suspensions were compounded in 1% methylcellulose:simple syrup at a 1:10 proportion for zonisamide, amitriptyline, and glycopyrrolate; these suspensions were stored at either under refrigeration (4°C) or at room temperature (25°C). The drug concentrations were measured by the stability-indicating high-performance liquid chromatographic methods. The mean concentration of zonisamide (10 mg/mL) remained above 95% of the original concentration for 91 days in each group of suspensions at both 4°C and 25°C. The mean concentration of amitriptyline (20 mg/mL) was above 95% for 91 days in the suspensions containing OraPlus/ OraSweet at both 4°C and 25°C. However, in the suspensions containing methylcellulose:simple syrup, the mean concentration of amitriptyline was about 95% for 42 days at 4°C and 28 days at 25°C. The mean concentration of glycopyrrolate (0.2 mg/mL) was above 95% in each group of suspensions during the 14-day study period. These data indicate that zonisamide, amitriptyline, and glycopyrrolate can be prepared extemporaneously as suspensions and stored in plastic prescription bottles for varying periods at 4°C and 25°C for use in pediatric patients. PMID:27323428

  17. Evaluation of Phosphorylated Psyllium Seed Polysaccharide as a Release Retardant.

    PubMed

    Rao, Monica R P; Warrier, Deepa U; Rao, Shivani H

    2015-01-01

    The aim of the present study was to modify psyllium seed polysaccharide and evaluate the modified polysaccharide as release retardant in tablets employing ciprofloxacin hydrochloride as model drug. Studies on polysaccharide from psyllium husk has been reported but no work has been reported on characterization and modification of the polysaccharide present in the psyllium (Plantago ovata) seed and the use of the modified polysaccharide as a release retardant in tablets. In this study, the seed gum was modified using sodium trimetaphosphate as crosslinking agent. Sustained release matrix tablets of ciprofloxacin hydrochloride were prepared by wet granulation using various drug-polymer ratios. The polymers investigated were psyllium polysaccharide, phosphorylated psyllium polysaccharide and widely used release retardant hydroxypropyl methylcellulose K100M. The tablets were evaluated for hardness, friability, drug content, swelling profile and in vitro dissolution studies. The matrix tablets containing 1:3 proportion of drug-phosphorylated psyllium polysaccharide was found to have higher hardness as compared to tablets containing 1:1 and 1:2 proportions. The results of swelling behavior in water showed that the tablets containing 1:3 drug:phosphorylated psyllium polysaccharide ratio had swelling comparable to that of tablets containing 1:3 drug:hydroxypropyl methylcellulose ratio. The in vitro dissolution studies shows that the dissolution rate was retarded from 98.41 to 37.6% in 6 h with increase in concentration of phosphorylated psyllium polysaccharide from 100 to 300 mg. Formulations containing psyllium polysaccharide showed complete drug release in 8 h whereas those formulated with phosphorylated psyllium polysaccharide exhibited extended drug release over the 12 h period. Drug release kinetic studies revealed that drug release followed Korsmeyer-Peppas model. PMID:26798177

  18. Effects of PMMA and Cross-Linked Dextran Filler for Soft Tissue Augmentation in Rats

    PubMed Central

    Huh, Jung-Bo; Kim, Joo-Hyun; Kim, Soyun; Lee, So-Hyoun; Shim, Kyung Mi; Kim, Se Eun; Kang, Seong Soo; Jeong, Chang-Mo

    2015-01-01

    This study was conducted for evaluation of the ability to maintain efficacy and biocompatibility of cross-linked dextran in hydroxypropyl methylcellulose (DiHM) and cross-linked dextran mixed with PMMA in hydroxypropyl methylcellulose (PDiHM), compared with hyaluronic acid (HA) filler. Saline and HA solution was administered in the negative and positive control groups, and DiHM and PDiHM were administered in the test groups (n = 10 in each group). The site of cranial subcutaneous injection was the mid-point of the interpupillary line, and the site of intraoral submucosal injection was the ridge crest 2 mm below the cervical line of the mandibular left incisor. Before and immediately after filler injection, intraoral photos and lateral cephalometric radiographs were taken for analysis and comparison of the effect of the filler on the injection sites. The filler injected areas were converted into sequential size changes (%) of the baseline. Histomorphologic examination was performed after 12 weeks. The smallest value in the filler injected area was observed during the experimental period in the normal saline group (p < 0.001), which was almost absorbed at 4 weeks (7.19% ± 12.72%). The HA group exhibited a steady decrease in sequential size and showed a lower value than the DiHM and PDiHM groups (saline < HA < DHiM, PDHiM, p < 0.001). DiHM and PDiHM tended to increase for the first 4 weeks and later decreased until 12 weeks. In this study on DiHM and PDiHM, there was no histological abnormality in cranial skin and oral mucosa. DiHM and PDiHM filler materials with injection system provide an excellent alternative surgical method for use in oral and craniofacial fields. PMID:26633376

  19. Preformulation and characterization of a lidocaine hydrochloride and dexamethasone sodium phosphate thermo-reversible and bioadhesive long-acting gel for intraperitoneal administration.

    PubMed

    Arbelaez-Camargo, Diana; Suñé-Negre, Josep Maria; Roig-Carreras, Manel; García-Montoya, Encarna; Pérez-Lozano, Pilar; Miñarro-Carmona, Montserrat; Ticó-Grau, Josep Ramon

    2016-02-10

    The search for new formulations of anaesthetic agents that allow a localized administration and provide a prolonged effect is of great interest in the multimodal management of postoperative pain. The pre-formulation and characterization of a lidocaine and dexamethasone thermosensitive and bioadhesive long-acting gel for intraperitoneal administration was done as a tool in the management of pain in abdominal surgeries. The pre-formulation process was conducted by a systematic variation of the concentration of the different polymers, until setting it, in a suitable concentration that allowed an adequate gelation temperature. The poloxamer 407 (P407) was used as the main polymer; hydroxypropyl methylcellulose (HPMC) as the bioadhesive agent and polyvinyl pyrrolidone (PVP) to adjust the gelation temperature and physicochemical properties. The formulations were characterized by gelation temperature, pH, viscosity at 25°C and 37°C, gelation time, density and osmolality. Gelation temperature was decreased when increasing the concentration of hydroxypropyl methylcellulose and poloxamer 407, this effect was also observed when adding lidocaine hydrochloride and dexamethasone sodium phosphate to the formulations. The gelation temperature did not have statistically significant relation with the PVP concentration (P-value of 0.6797), even though, there is a tendency in the gelation temperature by varying it. Between the developed formulations, the 12.5/3.3/0.4% (P407/HPMC/PVP) formulation presents an appropriate gelation temperature, a suitable viscosity for administration by syringe, an adequate and stable pH and osmolality to prevent tissue damage and a correct gelation time that allowed the formation of a prolonged release implant. PMID:26685726

  20. Flexible and printable paper-based strain sensors for wearable and large-area green electronics

    NASA Astrophysics Data System (ADS)

    Liao, Xinqin; Zhang, Zheng; Liao, Qingliang; Liang, Qijie; Ou, Yang; Xu, Minxuan; Li, Minghua; Zhang, Guangjie; Zhang, Yue

    2016-06-01

    Paper-based (PB) green electronics is an emerging and potentially game-changing technology due to ease of recycling/disposal, the economics of manufacture and the applicability to flexible electronics. Herein, new-type printable PB strain sensors (PPBSSs) from graphite glue (graphite powder and methylcellulose) have been fabricated. The graphite glue is exposed to thermal annealing to produce surface micro/nano cracks, which are very sensitive to compressive or tensile strain. The devices exhibit a gauge factor of 804.9, response time of 19.6 ms and strain resolution of 0.038%, all performance indicators attaining and even surpassing most of the recently reported strain sensors. Due to the distinctive sensing properties, flexibility and robustness, the PPBSSs are suitable for monitoring of diverse conditions such as structural strain, vibrational motion, human muscular movements and visual control.Paper-based (PB) green electronics is an emerging and potentially game-changing technology due to ease of recycling/disposal, the economics of manufacture and the applicability to flexible electronics. Herein, new-type printable PB strain sensors (PPBSSs) from graphite glue (graphite powder and methylcellulose) have been fabricated. The graphite glue is exposed to thermal annealing to produce surface micro/nano cracks, which are very sensitive to compressive or tensile strain. The devices exhibit a gauge factor of 804.9, response time of 19.6 ms and strain resolution of 0.038%, all performance indicators attaining and even surpassing most of the recently reported strain sensors. Due to the distinctive sensing properties, flexibility and robustness, the PPBSSs are suitable for monitoring of diverse conditions such as structural strain, vibrational motion, human muscular movements and visual control. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr02172g

  1. Detailed stability investigation of amorphous solid dispersions prepared by single-needle and high speed electrospinning.

    PubMed

    Démuth, B; Farkas, A; Pataki, H; Balogh, A; Szabó, B; Borbás, E; Sóti, P L; Vigh, T; Kiserdei, É; Farkas, B; Mensch, J; Verreck, G; Van Assche, I; Marosi, G; Nagy, Z K

    2016-02-10

    In this research the long-term stability (one year) of amorphous solid dispersions (ASDs) prepared by high speed electrospinning was investigated at 25 °C/60% relative humidity (RH) (closed conditions) and 40 °C/75% RH (open conditions). Single needle electrospinning and film casting were applied as reference technologies. Itraconazole (ITR) was used as the model API in 40% concentration and the ASDs consisted of either one of the following polymers as a comparison: polyvinylpyrrolidone-vinyl acetate 6:4 copolymer (no hydrogen bonds between API and polymer) and hydroxypropyl methylcellulose (possible hydrogen bonds between oxo or tertiary nitrogen function of API and hydroxyl moiety of polymer). DSC, XRPD and dissolution characteristics of samples at 0, 3 and 12 months were investigated. In addition, Raman maps of certain electrospun ASDs were assessed to investigate crystallinity. A new chemometric method, based on Multivariate Curve Resolution-Alternating Least Squares algorithm, was developed to calculate the spectrum of amorphous ITR in the matrices and to determine the crystalline/amorphous ratio of aged samples. As it was expected ITR in single needle electrospun SDs was totally amorphous at the beginning, in addition hydroxypropyl methylcellulose could keep ITR in this form at 40 °C/75% RH up to one year due to the hydrogen bonds and high glass transition temperature of the SD. In polyvinylpyrrolidone-vinyl acetate matrix ITR remained amorphous at 25 °C/60% RH throughout one year. Materials prepared by scaled-up, high throughput version of electrospinning, which is compatible with pharmaceutical industry, also gained the same quality. Therefore these ASDs are industrially applicable and with an appropriate downstream process it would be possible to bring them to the market. PMID:26705153

  2. Rifaximin diminishes neutropenia following potentially lethal whole-body radiation.

    PubMed

    Jahraus, Christopher D; Schemera, Bettina; Rynders, Patricia; Ramos, Melissa; Powell, Charles; Faircloth, John; Brawner, William R

    2010-07-01

    Terrorist attacks involving radiological or nuclear weapons are a substantial geopolitical concern, given that large populations could be exposed to potentially lethal doses of radiation. Because of this, evaluating potential countermeasures against radiation-induced mortality is critical. Gut microflora are the most common source of systemic infection following exposure to lethal doses of whole-body radiation, suggesting that prophylactic antibiotic therapy may reduce mortality after radiation exposure. The chemical stability, easy administration and favorable tolerability profile of the non-systemic antibiotic, rifaximin, make it an ideal potential candidate for use as a countermeasure. This study evaluated the use of rifaximin as a countermeasure against low-to-intermediate-dose whole-body radiation in rodents. Female Wistar rats (8 weeks old) were irradiated with 550 cGy to the whole body and were evaluated for 30 d. Animals received methylcellulose, neomycin (179 mg/kg/d) or variably dosed rifaximin (150-2000 mg/kg/d) one hour after irradiation and daily throughout the study period. Clinical assessments (e.g. body weight) were made daily. On postirradiation day 30, blood samples were collected and a complete blood cell count was performed. Animals receiving high doses of rifaximin (i.e. 1000 or 2000 mg/kg/d) had a greater increase in weight from the day of irradiation to postirradiation day 30 compared with animals that received placebo or neomycin. For animals with an increase in average body weight from irradiation day within 80-110% of the group average, methylcellulose rendered an absolute neutrophil count (ANC) of 211, neomycin rendered an ANC of 334, rifaximin 300 mg/kg/d rendered an ANC of 582 and rifaximin 1000 mg/kg/d rendered an ANC of 854 (P = 0.05 for group comparison). Exposure to rifaximin after near-lethal whole-body radiation resulted in diminished levels of neutropenia. PMID:20558844

  3. Formulation, Pharmacokinetic, and Efficacy Studies of Mannosylated Self-Emulsifying Solid Dispersions of Noscapine

    PubMed Central

    Andey, Terrick; Patel, Apurva; Marepally, Srujan; Chougule, Mahavir; Spencer, Shawn D.; Rishi, Arun K.; Singh, Mandip

    2016-01-01

    Purpose To formulate hydroxypropyl methylcellulose-stabilized self-emulsifying solid dispersible carriers of noscapine to enhance oral bioavailability. Methods Formulation of noscapine (Nos) self-emulsifying solid dispersible microparticles (SESDs) was afforded by emulsification using an optimized formula of Labrafil M1944, Tween-80, and Labrasol followed by spray-drying with hydroxypropyl methylcellulose (HPMC), with and without mannosamine (Mann-Nos_SESDs and Nos_SESDs respectively); self-microemulsifying liquid dispersions (SMEDDs) with and without mannosamine (Mann-Nos_SMEDDs and Nos_SMEDDs respectively) were also prepared. SMEDDs and SESDs were characterized for size, polydispersity, surface charge, entrapment efficiency, in vitro permeability, in vitro release kinetics, and oral pharmacokinetics in Sprague-Dawley rats (10 mg/kg p.o). The antitumor efficacy of Mann-Nos_SESDs on the basis of chemosensitization to cisplatin (2.0 mg/kg, IV) was investigated in a chemorefractory lung tumor Nu/Nu mouse model up to a maximal oral dose of 300 mg/kg. Results The oil/surfactant/co-surfactant mixture of Labrafil M1944, Tween-80, and Labrasol optimized at weight ratios of 62.8:9.30:27.90% produced stable self-microemulsifying dispersions (SMEDDs) at a SMEDD to water ratio of 1–3:7–9 parts by weight. SMEDDs had hydrodynamic diameters between 231 and 246 nm; surface charges ranged from -16.50 to -18.7 mV; and entrapment efficiencies were between 32 and 35%. SESDs ranged in size between 5.84 and 6.60 μm with surface charges from -10.62 to -12.40 mV and entrapment efficiencies of 30.96±4.66 and 32.05±3.72% (Nos_SESDs and Mann-Nos_SESDs respectively). Mann-Nos_SESDs exhibited saturating uptake across Caco-2 monolayers (Papp = 4.94±0.18 × 10−6 cm/s), with controlled release of 50% of Nos in 6 hr at pH 6.8 following Higuchi kinetics. Mann-Nos_ SESDs was 40% more bioavailable compared to Nos_SESDs; and was effective in sensitizing H1650 SP cells to Cisplatin in vitro

  4. A simple method for isolating chicken egg yolk immunoglobulin using effective delipidation solution and ammonium sulfate.

    PubMed

    Tong, Chenyao; Geng, Fang; He, Zhenjiao; Cai, Zhaoxia; Ma, Meihu

    2015-01-01

    Chicken egg yolk immunoglobulin (IgY) is a superior alternative to mammalian immunoglobulin. However, the practical application of IgY in research, diagnostics, and functional food is limited due to complex or time-consuming purification procedures. The objective of this study was to develop a simple, safe, large-scale separation method for IgY from egg yolk. Egg yolk was diluted with 6-fold delipidation solutions made of different types (pectin, λ-carrageenan, carboxymethylcellulose, methylcellulose, and dextran sulfate) and concentrations (0.01, 0.05, 0.1, 0.15, and 0.2%) of polysaccharides, respectively. The yolk solution was adjusted to pH 5.0, and then kept overnight at 4°C before being centrifuged at 4°C. The resulting supernatant was added to 35% (w/v) (NH4)2SO4 and then centrifuged. The precipitant, which contained IgY, was dissolved in distilled water and then dialyzed. SDS-PAGE and Western blotting were utilized to conduct qualitative analysis of IgY; high-performance liquid chromatography (HPLC) was used for quantitative analysis. The immunoreactivity of IgY was measured by ELISA. The results showed that yield, purity, and immunoreactivity varied with types and concentrations of polysaccharides. The optimal isolation of IgY for pectin, λ-carrageenan, dextran sulfate, and carboxymethylcellulose was at the concentration of 0.1%; for methylcellulose, optimal isolation was at 0.15%. The best results were obtained in the presence of 0.1% pectin. In this condition, yield and purity can reach 8.36 mg/mL egg yolk and 83.3%, respectively, and the negative effect of IgY on immunoreactivity can be minimized. The procedure of isolation was simplified to 2 steps with a higher yield of IgY, avoiding energy- and time-consuming methods. Therefore, the isolation condition under study has a great potential for food industry production of IgY on a large scale. PMID:25542196

  5. Genome-Wide DNA Methylation as an Epigenetic Consequence of Epstein-Barr Virus Infection of Immortalized Keratinocytes

    PubMed Central

    Birdwell, Christine E.; Queen, Krista J.; Kilgore, Phillip C. S. R.; Rollyson, Phoebe; Trutschl, Marjan; Cvek, Urska

    2014-01-01

    ABSTRACT The oral cavity is a persistent reservoir for Epstein-Barr virus (EBV) with lifelong infection of resident epithelial and B cells. Infection of these cell types results in distinct EBV gene expression patterns regulated by epigenetic modifications involving DNA methylation and chromatin structure. Regulation of EBV gene expression relies on viral manipulation of the host epigenetic machinery that may result in long-lasting host epigenetic reprogramming. To identify epigenetic events following EBV infection, a transient infection model was established to map epigenetic changes in telomerase-immortalized oral keratinocytes. EBV-infected oral keratinocytes exhibited a predominantly latent viral gene expression program with some lytic or abortive replication. Calcium and methylcellulose-induced differentiation was delayed in EBV-positive clones and in clones that lost EBV compared to uninfected controls, indicating a functional consequence of EBV epigenetic modifications. Analysis of global cellular DNA methylation identified over 13,000 differentially methylated CpG residues in cells exposed to EBV compared to uninfected controls, with CpG island hypermethylation observed at several cellular genes. Although the vast majority of the DNA methylation changes were silent, 65 cellular genes that acquired CpG methylation showed altered transcript levels. Genes with increased transcript levels frequently acquired DNA methylation within the gene body while those with decreased transcript levels acquired DNA methylation near the transcription start site. Treatment with the DNA methyltransferase inhibitor, decitabine, restored expression of some hypermethylated genes in EBV-infected and EBV-negative transiently infected clones. Overall, these observations suggested that EBV infection of keratinocytes leaves a lasting epigenetic imprint that can enhance the tumorigenic phenotype of infected cells. IMPORTANCE Here, we show that EBV infection of oral keratinocytes led to

  6. Influence of aqueous coatings on the stability of enteric coated pellets and tablets.

    PubMed

    Thoma, K; Bechtold, K

    1999-01-01

    Pancreatin pellets, placebo pellets and tablets containing vitamin B2 were coated with various aqueous and organic enteric polymers, HPMCAS, HP, Eudragit L 100-55, Eudragit L 30 D-55, CAP, CAT, CMEC and PVAP, comparatively investigated and tested for storage stability. With the exception of Eudragit L 100-55 and Eudragit L 30 D-55, higher amounts of coating material were needed to achieve gastro-resistance with aqueous coating than with organic coating. Film formation from aqueous dispersions of micronized HP 55 was affected by the degree of micronization and was improved by reducing the particle size of the polymer. Undercoating was another suitable measure to decrease the amount of coating material required. The choice of plasticizer was of special importance in the aqueous dispersions, and type and quantity must be appropriate for the polymer applied. Non-polymeric plasticizers such as triethyl citrate (TEC) evaporated along with water during the spraying or drying process and high temperatures promoted such losses. The moisture-sensitive pancreatic enzymes were damaged both by humidity and heat during aqueous coating. The extent of damage was dependent on the coating equipment used. Upon storage, coatings obtained from aqueous dispersions showed changes in enteric performance or release characteristics as a consequence of three chemical/physical mechanisms: hydrolysis of ester linkages in the polymer or plasticizer, evaporation of the plasticizer, delayed film formation. The active ingredient pancreatin induced hydrolysis of the ester based film-former hydroxypropyl methylcellulose acetate succinate (HPMCAS). However, even without the influence of enzymes, the phthalic ester groups of aqueous hydroxypropyl methylcellulose phthalate (HP) were partly cleaved after 11 months storage. In HPMCAS-coated pancreatin pellets, the plasticizer glyceryl triacetate was almost completely hydrolyzed by the enzymes, whilst triethyl citrate was lost by evaporation through

  7. The effects of multiple dosing with zileuton on antigen-induced responses in sheep.

    PubMed

    Scuri, M; Allegra, L; Abraham, W M

    1998-01-01

    In a previous study, a single dose of zileuton (10 mg/kg, po) given 2 h before antigen challenge, had a minimal effect on the antigen-induced early airway response (EAR), although it was effective in blocking the late airway response (LAR). Because our previous data indicated that 5-lipoxygenase (5-LO) products contribute to the severity of the antigen-induced EAR in these animals, we hypothesized that the lack of effect of zileuton on the EAR may have had to do with inadequate tissue levels. Therefore, in this study, we determined if multiple dosing with zileuton, which theoretically could improve tissue levels, would provide protection against the antigen-induced EAR as well as the LAR. Each sheep was used in each of the three trials (> or = 15 days apart), the order of which was randomized. For trial 1, the sheep were treated with zileuton (10 mg/kg in 0.1% methylcellulose, p.o.) once a day for 4 days; for trials 2, the sheep were treated with zileuton (10 mg/kg, p.o.) for 2 days; and, for trial 3, the animals were treated with vehicle (0.1% methylcellulose) for 4 days as in trial 1. In all trials, antigen challenge followed 1 h after the last treatment. In the placebo trial, antigen challenge resulted in characteristic EAR (407 +/- 102%, increase over baseline) and LAR (335 +/- 75%, increase over baseline). The antigen-induced effects were completely blocked by the 4-day treatment (EAR = 24 +/- 3%; LAR = 17 +/- 3%, P < 0.05 vs. placebo). In the 2-day trial, the immediate increase in R1, after antigen challenge was only partially blocked (EAR = 163 +/- 16%, P < 0.10 vs. placebo and P < 0.05 vs. 4-day trial), but the late response was completely blocked (24 +/- 3%). The protection against the EAR obtained with the 4-day treatment was significantly better (P < 0.05) than that obtained with the 2-day treatment. The results of this study show that multiple dosing with the 5-LO inhibitor, zileuton, provides protection against the antigen-induced EAR as well as LAR

  8. Endogenously elevated bilirubin modulates kidney function and protects from circulating oxidative stress in a rat model of adenine-induced kidney failure

    PubMed Central

    Boon, Ai-Ching; Lam, Alfred K.; Gopalan, Vinod; Benzie, Iris F.; Briskey, David; Coombes, Jeff S.; Fassett, Robert G.; Bulmer, Andrew C.

    2015-01-01

    Mildly elevated bilirubin is associated with a reduction in the presence and progression of chronic kidney disease and related mortality, which may be attributed to bilirubin’s antioxidant properties. This study investigated whether endogenously elevated bilirubin would protect against adenine-induced kidney damage in male hyperbilirubinaemic Gunn rats and littermate controls. Animals were orally administered adenine or methylcellulose solvent (vehicle) daily for 10 days and were then monitored for 28 days. Serum and urine were assessed throughout the protocol for parameters of kidney function and antioxidant/oxidative stress status and kidneys were harvested for histological examination upon completion of the study. Adenine-treated animals experienced weight-loss, polyuria and polydipsia; however, these effects were significantly attenuated in adenine-treated Gunn rats. No difference in the presence of dihydroadenine crystals, lymphocytic infiltration and fibrosis were noted in Gunn rat kidneys versus controls. However, plasma protein carbonyl and F2-isoprostane concentrations were significantly decreased in Gunn rats versus controls, with no change in urinary 8-oxo-7,8-dihydro-2′-deoxyguanosine or kidney tissue F2-isoprostane concentrations. These data indicated that endogenously elevated bilirubin specifically protects from systemic oxidative stress in the vascular compartment. These data may help to clarify the protective relationship between bilirubin, kidney function and cardiovascular mortality in clinical investigations. PMID:26498893

  9. Nano-pulverization of poorly water soluble compounds with low melting points by a rotation/revolution pulverizer.

    PubMed

    Yuminoki, K; Takeda, M; Kitamura, K; Numata, S; Kimura, K; Takatsuka, T; Hashimoto, N

    2012-08-01

    We report a method for pulverizing poorly water soluble compounds with low melting points to nanoparticles without producing an amorphous phase using a rotation/revolution pulverizer. Fenofibrate, flurbiprofen, and probucol were used as crystalline model compounds. They were suspended in a methylcellulose aqueous solution and pulverized with zirconia balls by the rotation/revolution pulverizer. Beeswax, an amorphous compound, was also examined to investigate whether nano-pulverization of a compound with a low melting point was possible. Beeswax was suspended in ethyl alcohol cooled with liquid nitrogen and pulverized with zirconia balls by the rotation/revolution pulverizer. By optimizing the pulverization parameters, nanoparticles (D50 < 0.15 microm) of the crystalline compounds were obtained with narrow particle size distributions at a rotation/revolution speed of 1000 rpm and a rotation/revolution ratio of 1.0 when the vessel was 0 degrees C. Amorphous fenofibrate and flurbiprofen were not detected by differential scanning calorimetry or powder X-ray diffraction, whereas small amounts of amorphous probucol were detected. Beeswax was pulverized to nanoparticles (D50 = 0.14 microm) with ethyl alcohol cooled with liquid nitrogen. Fine nanoparticles of these poorly water soluble compounds with low melting points were obtained by controlling the rotation/revolution speed and reducing the vessel temperature. PMID:22957432

  10. Nitric oxide suppression of human hematopoiesis in vitro. Contribution to inhibitory action of interferon-gamma and tumor necrosis factor-alpha.

    PubMed Central

    Maciejewski, J P; Selleri, C; Sato, T; Cho, H J; Keefer, L K; Nathan, C F; Young, N S

    1995-01-01

    IFN-gamma and TNF-alpha, potent inhibitors of hematopoiesis, induce nitric oxide synthase (NOS) in various cell types. When normal human bone marrow (BM) or CD34+ cells were exposed to NO, inhibition of colony formation was dose dependent and direct. NO induced apoptosis in BM progenitors, as shown by electrophoretic detection of DNA degradation and deoxynucleotidyl transferase assay. Using PCR and immunoprecipitation, we found inducible NOS (iNOS) mRNA and iNOS protein in BM after stimulation with IFN-gamma or TNF-alpha. iNOS mRNA was also detected by PCR in highly purified CD34+ cells; TNF-alpha or IFN-gamma increased iNOS expression. The presence of iNOS in CD34+ cells was confirmed in single cells by immunochemical staining. NG-Monomethyl-L-arginine (MM-Arg), an NOS inhibitor, partially reversed the effects of TNF-alpha and, to a lesser extent, IFN-gamma in methylcellulose culture of total BM and CD34+ cells, and inhibited apoptosis of BM cells induced by these cytokines. When the effects of competitive iNOS inhibition were tested on more immature progenitors, MM-Arg increased the number of long-term BM culture-initiating cells in control cultures but failed to protect these cells from the inhibitory action of IFN-gamma and TNF-alpha. Our results suggest that NO may be one mediator of cytokine-induced hematopoietic suppression. Images PMID:7543491

  11. Encapsulation and Delivery of Crystalline Hydrophobic Nutraceuticals using Nanoemulsions: Factors Affecting Polymethoxyflavone Solubility.

    PubMed

    Li, Yan; Xiao, Hang; McClements, David Julian

    2012-12-01

    Polymethoxyflavones (PMF) isolated from citrus peel have potent anti-cancer activity, however their utilization as functional ingredients in foods is currently limited because of their high melting point and poor water-solubility. The influence of oil type and concentration, hydrophilic polymer addition, and simulated intestinal conditions on PMF (5-hydroxytangeretin) solubility in solutions and nanoemulsions was examined. The saturation concentration of PMF in water was relatively low (0.93 µM), but could be increased appreciably by adding certain hydrophilic polymers: polyethylene glycol (PEG) and β-cyclodextrin (CD) were ineffective at increasing solubility, but poly(vinyl alcohol) (PVA) and hydroxypropyl methylcellulose (HPMC) greatly enhanced solubility (e.g., > 6 µM for 0.5 % polymer). PMF was more soluble in medium chain triglycerides (MCT, 6.1 mM) than long chain triglycerides (LCT, 4.2 mM). The encapsulation efficiency of PMF in oil-in-water nanoemulsions was higher when MCT was used as the oil phase rather than LCT, and could be increased by increasing the oil droplet content. The solubility of PMF in simulated small intestinal fluids was increased by solubilization in bile micelles and mixed micelles formed during lipid digestion. These results have important implications for the development of functional foods fortified with bioactive hydrophobic components aimed at improving human health and wellness. PMID:23646037

  12. PBPK Model for Atrazine and Its Chlorotriazine Metabolites in Rat and Human

    PubMed Central

    Campbell, Jerry L.; Andersen, Melvin E.; Hinderliter, Paul M.; Yi, Kun Don; Pastoor, Timothy P.; Breckenridge, Charles B.; Clewell, Harvey J.

    2016-01-01

    The previously-published physiologically based pharmacokinetic model for atrazine (ATZ), deisopropylatrazine (DIA), deethylatrazine (DEA), and diaminochlorotriazine (DACT), which collectively comprise the total chlorotriazines (TCT) as represented in this study, was modified to allow for scaling to humans. Changes included replacing the fixed dose-dependent oral uptake rates with a method that represented delayed absorption observed in rats administered ATZ as a bolus dose suspended in a methylcellulose vehicle. Rate constants for metabolism of ATZ to DIA and DEA, followed by metabolism of DIA and DEA to DACT were predicted using a compartmental model describing the metabolism of the chlorotriazines by rat and human hepatocytes in vitro. Overall, the model successfully predicted both the 4-day plasma time-course data in rats administered ATZ by bolus dose (3, 10, and 50 mg/kg/day) or in the diet (30, 100, or 500 ppm). Simulated continuous daily exposure of a 55-kg adult female to ATZ at a dose of 1.0 µg/kg/day resulted in steady-state urinary concentrations of 0.6, 1.4, 2.5, and 6.0 µg/L for DEA, DIA, DACT, and TCT, respectively. The TCT (ATZ + DEA + DIA + DACT) human urinary biomonitoring equivalent concentration following continuous exposure to ATZ at the chronic point of departure (POD = 1.8 mg/kg/day) was 360.6 μg/L. PMID:26794140

  13. The multiple myeloma–associated MMSET gene contributes to cellular adhesion, clonogenic growth, and tumorigenicity

    PubMed Central

    Abukhdeir, Abde M.; Konishi, Hiroyuki; Garay, Joseph P.; Gustin, John P.; Wang, Qiuju; Arceci, Robert J.; Matsui, William

    2008-01-01

    Multiple myeloma (MM) is an incurable hematologic malignancy characterized by recurrent chromosomal translocations. Patients with t(4;14)(p16;q32) are the worst prognostic subgroup in MM, although the basis for this poor prognosis is unknown. The t(4;14) is unusual in that it involves 2 potential target genes: fibroblast growth factor receptor 3 (FGFR3) and multiple myeloma SET domain (MMSET). MMSET is universally overexpressed in t(4;14) MM, whereas FGFR3 expression is lost in one-third of cases. Nonetheless, the role of MMSET in t(4;14) MM has remained unclear. Here we demonstrate a role for MMSET in t(4;14) MM cells. Down-regulation of MMSET expression in MM cell lines by RNA interference and by selective disruption of the translocated MMSET allele using gene targeting dramatically reduced colony formation in methylcellulose but had only modest effects in liquid culture. In addition, MMSET knockdown led to cell-cycle arrest of adherent MM cells and reduced the ability of MM cells to adhere to extracellular matrix. Finally, MMSET knockdown and knockout reduced tumor formation by MM xenografts. These results provide the first direct evidence that MMSET plays a significant role in t(4;14) MM and suggest that therapies targeting this gene could impact this particular subset of poor-prognosis patients. PMID:17942756

  14. Astringency reduction in red wine by whey proteins.

    PubMed

    Jauregi, Paula; Olatujoye, Jumoke B; Cabezudo, Ignacio; Frazier, Richard A; Gordon, Michael H

    2016-05-15

    Whey is a by-product of cheese manufacturing and therefore investigating new applications of whey proteins will contribute towards the valorisation of whey and hence waste reduction. This study shows for the first time a detailed comparison of the effectiveness of gelatin and β-lactoglobulin (β-LG) as fining agents. Gelatin was more reactive than whey proteins to tannic acid as shown by both the astringency method (with ovalbumin as a precipitant) and the tannins determination method (with methylcellulose as a precipitant). The two proteins showed similar selectivity for polyphenols but β-LG did not remove as much catechin. The fining agent was removed completely or to a trace level after centrifugation followed by filtration which minimises its potential allergenicity. In addition, improved understanding of protein-tannin interactions was obtained by fluorescence, size measurement and isothermal titration calorimetry (ITC). Overall this study demonstrates that whey proteins have the potential of reducing astringency in red wine and can find a place in enology. PMID:26776007

  15. Formulation, physicochemical characterization, and in vitro study of chitosan/HPMC blends-based herbal blended patches.

    PubMed

    Suksaeree, Jirapornchai; Monton, Chaowalit; Madaka, Fameera; Chusut, Tun; Saingam, Worawan; Pichayakorn, Wiwat; Boonme, Prapaporn

    2015-02-01

    The current work prepared chitosan/hydroxypropyl methylcellulose (HPMC) blends and studied the possibility of chitosan/HPMC blended patches for Zingiber cassumunar Roxb. The blended patches without/with crude Z. cassumunar oil were prepared by homogeneously mixing the 3.5% w/v of chitosan solution and 20% w/v of HPMC solution, and glycerine was used as plasticizer. Then, they were poured into Petri dish and produced the blended patches in hot air oven at 70 ± 2°C. The blended patches were tested and evaluated by the physicochemical properties: moisture uptake, swelling ratio, erosion, porosity, Fourier transform infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction, and photographed the surface and cross-section morphology under SEM technique. Herbal blended patches were studied by the in vitro release and skin permeation of active compound D. The blended patches could absorb the moisture and became hydrated patches that occurred during the swelling of blended patches. They were eroded and increased by the number of porous channels to pass through out for active compound D. In addition, the blended patches indicated the compatibility of the blended ingredients and homogeneous smooth and compact. The blended patches made from chitosan/HPMC blends provide a controlled release and skin permeation behavior of compound D. Thus, the blended patches could be suitably used for herbal medicine application. PMID:25233803

  16. Effect of methanol extract of Basella alba L. (Basellaceae) on the fecundity and testosterone level in male rats exposed to flutamide in utero.

    PubMed

    Nantia, E A; Manfo, P F T; Beboy, N E; Travert, C; Carreau, S; Monsees, T K; Moundipa, P F

    2012-02-01

    We evaluated the effect of the methanol extract of Basella alba (MEBa) on testosterone level and fecundity/fertility in male rats exposed in utero to flutamide - an androgen receptor antagonist. For this purpose, 1.5- and 2.5 -month-old male rats exposed in utero to flutamide were treated with the MEBa (1 mg kg(-1) ) for 2 and 1 month respectively. Five days before the end of treatment, rats were housed with females to assess their fecundity/fertility. Thereafter, rats were sacrificed and blood collected for the quantification of testosterone. Flutamide-exposed male rats showed a decrease in their ano-genital distance (AGD, P < 0.05) and were infertile. In normal (methylcellulose-exposed) animals, MEBa provoked an increase in testosterone level in 1.5- (P < 0.008) and 2.5 -month-old rats (P < 0.01) concomitantly with the improvement in their fecundity by 25%. In flutamide-exposed male rats, MEBa increased testosterone level in 1.5 -month-old rats (P < 0.001) without any effect on their fecundity; while in 2.5- month-old rats, MEBa did not affect the testosterone level but improved fecundity (by 25%) and fertility (P < 0.001). This study demonstrated the positive effect of MEBa to enhance fecundity/fertility in normal male rats and in rats exposed to the antiandrogen flutamide during their foetal life. PMID:21592171

  17. Determination of ephedrine and pseudoephedrine by field-amplified sample injection capillary electrophoresis.

    PubMed

    Deng, Dongli; Deng, Hao; Zhang, Lichun; Su, Yingying

    2014-04-01

    A simple and rapid capillary electrophoresis method was developed for the separation and determination of ephedrine (E) and pseudoephedrine (PE) in a buffer solution containing 80 mM of NaH2PO4 (pH 3.0), 15 mM of β-cyclodextrin and 0.3% of hydroxypropyl methylcellulose. The field-amplified sample injection (FASI) technique was applied to the online concentration of the alkaloids. With FASI in the presence of a low conductivity solvent plug (water), an approximately 1,000-fold improvement in sensitivity was achieved without any loss of separation efficiency when compared to conventional sample injection. Under these optimized conditions, a baseline separation of the two analytes was achieved within 16 min and the detection limits for E and PE were 0.7 and 0.6 µg/L, respectively. Without expensive instruments or labeling of the compounds, the limits of detection for E and PE obtained by the proposed method are comparable with (or even lower than) those obtained by capillary electrophoresis laser-induced fluorescence, liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry. The method was validated in terms of precision, linearity and accuracy, and successfully applied for the determination of the two alkaloids in Ephedra herbs. PMID:23619557

  18. Refinement of nano-structured fibroin thin films by near-IR pulsed laser deposition from targets consolidated with autogenous binder.

    PubMed

    Nakayama, S; Nozaki, R; Senna, M

    2008-01-01

    Silk fibroin (SF) powders were mixed with an autogenous binder from a natural cocoon after degumming with Na(2)CO(3) and liquefied with LiBr. An all-fibroin ablation target, SLT, obtained from the mixture after compression at ambient temperature, was compared with those without autogenous binder, SWT, or with a simple, non-autogenous binder, hydroxypropyl methylcellulose, SHT. The targets were then irradiated by a 1064 nm laser beam to obtain nano-structured thin films of fibroin by pulsed laser deposition (PLD) on Si (100). The properties of PLD films were examined mainly by atomic force microscope (AFM) or scanning electron microscope (SEM) for microstructures and morphology. By using an autogenous binder, significant increase was observed in the rate of nanofilm deposition with simultaneous decrease in the fraction of large debris. Size reduction of smallest protein units (SPUs) was also recognized by AFM. The autogenous binder turned out to be significantly superior over conventional, non-autogenous ones. PMID:18544238

  19. Management of Constipation in Older Adults.

    PubMed

    Mounsey, Anne; Raleigh, Meghan; Wilson, Anthony

    2015-09-15

    Chronic constipation is common in adults older than 60 years, and symptoms occur in up to 50% of nursing home residents. Primary constipation is also referred to as functional constipation. Secondary constipation is associated with chronic disease processes, medication use, and psychosocial issues. Fecal impaction should be treated with mineral oil or warm water enemas. Most patients are initially treated with lifestyle modifications, such as scheduled toileting after meals, increased fluid intake, and increased dietary fiber intake. Additional fiber intake in the form of polycarbophil, methylcellulose, or psyllium may improve symptoms. Fiber intake should be slowly increased over several weeks to decrease adverse effects. The next step in the treatment of constipation is the use of an osmotic laxative, such as polyethylene glycol, followed by a stool softener, such as docusate sodium, and then stimulant laxatives. Long-term use of magnesium-based laxatives should be avoided because of potential toxicity. If symptoms do not improve, a trial of linaclotide or lubiprostone may be appropriate, or the patient may be referred for further diagnostic evaluation. Peripherally acting mu-opioid antagonists are effective for opioid-induced constipation but are expensive. PMID:26371734

  20. Physicochemical and microbiological properties of selected rice flour-based batters for fried chicken drumsticks.

    PubMed

    Mukprasirt, A; Herald, T J; Boyle, D L; Boyle, E A

    2001-07-01

    Rice flour-based batter (RFBB) formulations for chicken drumstick coating were developed as an alternative for traditional wheat flour-based batter (WFBB). Physicochemical properties and storage stability of selected RFBB were evaluated and compared to WFBB. Batter pickup of RFBB formulated in combination with oxidized corn starch and methylcellulose (MC) was not significantly different from that of WFBB. In contrast, batters with only rice and corn flour (60:40% flour weight) exhibited significantly higher pickup. Rice flour batter with 15% oxidized corn starch had the lowest batter pickup. All RFBB exhibited (P < 0.05) lower oil absorption than WFBB. The TBA values of RFBB and WFBB increased (P < 0.05) with increased frozen storage time at -40 C for 90 d. The RFBB with MC exhibited the lowest TBA values, whereas WFBB had the highest values. Microstructural analysis revealed that freezing caused structural deterioration of all batters, but the RFBB with MC exhibited less freezing tolerance than other samples. The total plate counts of immediately fried or frozen fried chicken stored for 90 d were less than 1 log cfu/g sample. The RFBB with 5% oxidized corn starch and MC can replace WFBB on fried drumsticks. Additionally, RFBB results in a healthier product due to lower fat absorption. PMID:11469667

  1. Formulation, preparation, and evaluation of novel orally disintegrating tablets containing taste-masked naproxen sodium granules and naratriptan hydrochloride.

    PubMed

    Stange, Ulrike; Führling, Christian; Gieseler, Henning

    2014-04-01

    The purpose of this study was to develop and manufacture novel freeze-dried orally disintegrating tablets (ODTs) for migraine therapy containing taste-masked naproxen sodium and naratriptan hydrochloride. The formulation was optimized based on freeze-drying of sucrose solutions with different binders (hydroxyethylstarch, sodium alginate, methylcellulose, and gelatin) and varying amounts of Eudragit® E-coated naproxen sodium granules. Excellent product performance of the ODTs in terms of hardness and disintegration time (<10 s) independent of the mass of particles embedded was found for the solution consisting of sucrose and hydroxyethylstarch. Poloxamer 188, menthol flavor, naratriptan hydrochloride, and taste-masked naproxen sodium granules corresponding to 200 mg of naproxen were then added, and the final batches of ODTs for migraine therapy were produced. The ODTs were fully characterized, and subsequently stored for 1 month at room temperature and at 40°C. The amount of free naproxen sodium after freeze-drying and storage was below the threshold bitterness value, and the coating remained intact. Additionally, the particle size distribution of taste-masked granules was preserved, and more than 90 % naproxen sodium was released after 30 min. Naratriptan hydrochloride was dissolved immediately after disintegration, hence facilitating buccal absorption of the active pharmaceutical ingredient. PMID:24532095

  2. Orodispersible films and tablets with prednisolone microparticles.

    PubMed

    Brniak, Witold; Maślak, Ewelina; Jachowicz, Renata

    2015-07-30

    Orodispersible tablets (ODTs) and orodispersible films (ODFs) are solid oral dosage forms disintegrating or dissolving rapidly when placed in the mouth. One of the main issues related to their preparation is an efficient taste masking of a bitter drug substance. Therefore, the aim of this study was to prepare and evaluate the microparticles intended to mask a bitter taste of the prednisolone and use them in further preparation of two orodispersible dosage forms. Microparticles based on the Eudragit E PO or E 100 as a taste-masking agent were prepared with spray-drying technique. Tablets containing microparticles, co-processed ODT excipient Pharmaburst, and lubricant were directly compressed with single-punch tablet press. Orodispersible films were prepared by casting polymeric solutions of hydroxypropyl methylcellulose containing uniformly dispersed microparticles. Physicochemical properties of microparticles were evaluated, as well as mechanical properties analysis, disintegration time measurements and dissolution tests were performed for prepared dosage forms. Both formulations showed good mechanical resistance while maintaining excellent disintegration properties. The dissolution studies showed good masking properties of microparticles with Eudragit E 100. The amount of prednisolone released during the first minute in phosphate buffer 6.8 was around 0.1%. After incorporation into the orodispersible forms, the amount of released prednisolone increased significantly. It was probably the effect of faster microparticles wetting in orodispersible forms and their partial destruction by compression force during tableting process. PMID:25889975

  3. Formulation and evaluation of mucoadhesive tablets containing eugenol for the treatment of periodontal diseases.

    PubMed

    Jadhav, Bhimrao K; Khandelwal, Kishanchandra R; Ketkar, Anant R; Pisal, Sambhaji S

    2004-02-01

    Eugenol is the principle chemical constituent of clove oil and has been used to cure dental problems for ages. Eugenol is an integral part of the dentist's kit due to its analgesic, local anesthetic, anti-inflammatory, and antibacterial effects. It is used in the form of a paste or mixture as dental cement, filler, and restorative material. This study reports the development and evaluation of controlled-release mucoadhesive tablets for gingival application, containing eugenol, which are prepared by taking carbopol 934 P and Hydroxypropyl methylcellulose (HPMC) K4M in the ratio of 1:2, 1:1, and 2:1. Incorporation of eugenol (10 mg) in a mucoadhesive formulation provides controlled release for a period of 8 hours, which is advantageous over conventional use. In vitro mucoadhesion measured as detachment force in grams and the formulations show good correlation in vivo. The release study indicates that increase in carbopol increases the release rate of eugenol from the formulation whereas HPMC retards it. Increased in vitro bioadhesion is related to HPMC content of the formulation. The release kinetics of eugenol in vitro correlates with the in vivo results. This indicates the increased potential of eugenol as antibacterial, local analgesic, and anaesthetic treatment. PMID:15089054

  4. Enhancement of bioavailability of cefpodoxime proxetil using different polymeric microparticles.

    PubMed

    Khan, Fahim; Katara, Rajesh; Ramteke, Suman

    2010-09-01

    Poorly water-soluble drugs such as cefpodoxime proxetil (400 μg/ml) offer a challenging problem in drug formulation as poor solubility is generally associated with poor dissolution characteristics and thus poor oral bioavailability. According to these characteristics, preparation of cefpodoxime proxetil microparticle has been achieved using high-speed homogenization. Polymers (methylcellulose, sodium alginate, and chitosan) were precipitated on the surface of cefpodoxime proxetil using sodium citrate and calcium chloride as salting-out agents. The pure drug and the prepared microparticles with different concentrations of polymer (0.05-1.0%) were characterized in terms of solubility, drug content, particle size, thermal behavior (differential scanning calorimeter), surface morphology (scanning electron microscopy), in vitro drug release, and stability studies. The in vivo performance was assessed by pharmacokinetic study. The dissolution studies demonstrate a marked increase in the dissolution rate in comparison with pure drug. The considerable improvement in the dissolution rate of cefpodoxime proxetil from optimized microparticle was attributed to the wetting effect of polymers, altered surface morphology, and micronization of drug particles. The optimized microparticles exhibited excellent stability on storage at accelerated condition. The in vivo studies revealed that the optimized formulations provided improved pharmacokinetic parameter in rats as compared with pure drug. The particle size of drug was drastically reduced during formulation process of microparticles. PMID:20821175

  5. Regulation of mir-196b by MLL and its overexpression by MLL fusions contributes to immortalization

    PubMed Central

    Popovic, Relja; Riesbeck, Laurie E.; Velu, Chinavenmeni S.; Chaubey, Aditya; Zhang, Jiwang; Achille, Nicholas J.; Erfurth, Frank E.; Eaton, Katherine; Lu, Jun; Grimes, H. Leighton; Chen, Jianjun; Rowley, Janet D.

    2009-01-01

    Chromosomal translocations involving the Mixed Lineage Leukemia (MLL) gene produce chimeric proteins that cause abnormal expression of a subset of HOX genes and leukemia development. Here, we show that MLL normally regulates expression of mir-196b, a hematopoietic microRNA located within the HoxA cluster, in a pattern similar to that of the surrounding 5′ Hox genes, Hoxa9 and Hoxa10, during embryonic stem (ES) cell differentiation. Within the hematopoietic lineage, mir-196b is most abundant in short-term hematopoietic stem cells and is down-regulated in more differentiated hematopoietic cells. Leukemogenic MLL fusion proteins cause overexpression of mir-196b, while treatment of MLL-AF9 transformed bone marrow cells with mir-196–specific antagomir abrogates their replating potential in methylcellulose. This demonstrates that mir-196b function is necessary for MLL fusion-mediated immortalization. Furthermore, overexpression of mir-196b was found specifically in patients with MLL associated leukemias as determined from analysis of 55 primary leukemia samples. Overexpression of mir-196b in bone marrow progenitor cells leads to increased proliferative capacity and survival, as well as a partial block in differentiation. Our results suggest a mechanism whereby increased expression of mir-196b by MLL fusion proteins significantly contributes to leukemia development. PMID:19188669

  6. In vitro assays misrepresent in vivo lineage potentials of murine lymphoid progenitors.

    PubMed

    Richie Ehrlich, Lauren I; Serwold, Thomas; Weissman, Irving L

    2011-03-01

    The identity of T-cell progenitors that seed the thymus has remained controversial, largely because many studies differ over whether these progenitors retain myeloid potential. Contradictory reports diverge in their use of various in vitro and in vivo assays. To consolidate these discordant findings, we compared the myeloid potential of 2 putative thymus seeding populations, common lymphoid progenitors (CLPs) and multipotent progenitors (MPPs), and the earliest intrathymic progenitor (DN1), using 2 in vitro assays and in vivo readouts. These assays gave contradictory results: CLP and DN1 displayed surprisingly robust myeloid potential on OP9-DL1 in vitro stromal cocultures but displayed little myeloid potential in vivo, as well as in methylcellulose cultures. MPP, on the other hand, displayed robust myeloid potential in all settings. We conclude that stromal cocultures reveal cryptic, but nonphysiologic, myeloid potentials of lymphoid progenitors, providing an explanation for contradictory findings in the field and underscoring the importance of using in vivo assays for the determination of physiologic lineage potentials. PMID:21163922

  7. A novel floating controlled release drug delivery system prepared by hot-melt extrusion.

    PubMed

    Vo, Anh Q; Feng, Xin; Morott, Joseph T; Pimparade, Manjeet B; Tiwari, Roshan V; Zhang, Feng; Repka, Michael A

    2016-01-01

    Floating dosage forms are an important formulation strategy for drugs with a narrow absorption window and low intestinal solubility, and for localized gastric treatment. Novel floating pellets were prepared using the hot-melt extrusion (HME) technology. Uniformly foamed strands were created by liquid injection pumping and screw configuration modification. The ammonio methacrylate copolymer (Eudragit® RSPO) foaming structure was formed by a liquid-vapor phase transition inside the strand upon die exiting resulting from the sudden decrease in external pressure, vaporizing the liquid ethanol and vacating the extruded material. This generated uniform vacuous regions in the extrudate. The pellets' internal structure was investigated using scanning electron microscopy (SEM). The formulation constituents' and processing parameters' effects on the drug release profiles, floating force, and the pellets' micromeritic properties were evaluated by design of experiments: all formulations showed zero lag time and excellent floating strength, indicating immediate-floating pellet formation. The pellets' drug release profiles were controlled by multiple independent variables at different time points (⩽ 24 h). Drug loading significantly affected drug release within the first hour, the hydroxypropyl methylcellulose (HPMC) content thereafter. Understanding the variables' effects on the formulations allows for the tailoring of this delivery system to obtain various drug release profiles. PMID:26643801

  8. Ion-activated In Situ Gelling Ophthalmic Delivery Systems of Azithromycin

    PubMed Central

    Vijaya, C.; Goud, K. Swetha

    2011-01-01

    Gelation of pectin caused by divalent cations especially calcium ions has been applied to develop an ophthalmic formulation of azithromycin in the present study. Rapid elimination of drug on instillation into cul de sac would be minimal with in situ gelling ophthalmic solution leading to increased precorneal contact time and prolonged drug delivery. In the formulation development studies pectin was used in different concentrations (1-5% w/v) and different proportions of the hydrocolloids hydroxypropyl methylcellulose and sodium carboxymethyl cellulose of different grades of viscosity were used. The primary criteria for formulation optimization were gelling capacity and rheological behaviour. In addition, formulations were evaluated for pH, and antimicrobial efficacy and drug release. The clarity, pH, gelation in simulated tear fluid and rheological properties of the optimized formulations were satisfactory. The formulations inhibited the growth of Staphylococcus aureus effectively in cup–plate method and were proved to be safe and non irritant on rabbit eyes. The results indicate that pectin based in situ gels can be successfully used to prolong the duration of action of azithromycin. PMID:23112394

  9. The fate of free radicals in a cellulose based hydrogel: detection by electron paramagnetic resonance spectroscopy.

    PubMed

    Basumallick, Lipika; Ji, J Andrea; Naber, Nariman; Wang, Y John

    2009-07-01

    Cellulose derivatives are commonly used as gelling agents in topical and ophthalmic drug formulations. During the course of manufacturing, cellulose derivatives are believed to generate free radicals. These free radicals may degrade the gelling agent, leading to lower viscosity. Free radicals also may react with the active ingredient in the product. The formation of radicals in a 3% hydrogel of hypromellose (hydroxypropyl methylcellulose) was monitored by electron paramagnetic resonance (EPR) spectroscopy and spin trapping techniques. Radicals were trapped with 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) and quantitated by comparing the EPR intensity with 4-hydroxy-2,2,6,6-tetramethylpiperidinyloxy (TEMPOL), a stable free radical. Typically, the hydrogels showed an initial increase in the radical concentration within 2 days after autoclaving, followed by a drop in radical concentration in 7 days. EDTA prevented the formation of free radicals in the hypromellose (HPMC) hydrogel, suggesting the involvement of metal ions in the generation of free radicals. The oxidizing potential of the hydrogel was estimated by measuring the rate at which methionine (a model for the protein active pharmaceutical ingredient) was degraded, and was consistent with the amount of radicals present in the gel. This study is the first report investigating the application of EPR spectroscopy in detecting and estimating free radical concentration in cellulose based hydrogels. PMID:19090570

  10. Pre-clinical Evaluation of Tyrosine Kinase Inhibitors for Treatment of Acute Leukemia

    PubMed Central

    Christoph, Sandra; Lee-Sherick, Alisa B.; Sather, Susan; DeRyckere, Deborah; Graham, Douglas K.

    2013-01-01

    Receptor tyrosine kinases have been implicated in the development and progression of many cancers, including both leukemia and solid tumors, and are attractive druggable therapeutic targets. Here we describe an efficient four-step strategy for pre-clinical evaluation of tyrosine kinase inhibitors (TKIs) in the treatment of acute leukemia. Initially, western blot analysis is used to confirm target inhibition in cultured leukemia cells. Functional activity is then evaluated using clonogenic assays in methylcellulose or soft agar cultures. Experimental compounds that demonstrate activity in cell culture assays are evaluated in vivo using NOD-SCID-gamma (NSG) mice transplanted orthotopically with human leukemia cell lines. Initial in vivo pharmacodynamic studies evaluate target inhibition in leukemic blasts isolated from the bone marrow. This approach is used to determine the dose and schedule of administration required for effective target inhibition. Subsequent studies evaluate the efficacy of the TKIs in vivo using luciferase expressing leukemia cells, thereby allowing for non-invasive bioluminescent monitoring of leukemia burden and assessment of therapeutic response using an in vivo bioluminescence imaging system. This strategy has been effective for evaluation of TKIs in vitro and in vivo and can be applied for identification of molecularly-targeted agents with therapeutic potential or for direct comparison and prioritization of multiple compounds. PMID:24084362