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Sample records for polyox wsr-fra polyox

  1. The role of fillers and sodium metabisulfite on drug release from aged polyox tablets.

    PubMed

    Shojaee, Saeed; Nokhodchi, Ali; Cumming, Iain

    2014-11-01

    Polyethylene oxides (PEOs) are extensively used to control the release rate of drugs from matrices. Unfortunately, polyox polymers are prone to oxidation under high temperature and relative humidity. The aim of this study was to investigate the effect of sodium metabisulfite as an antioxidant to overcome the drug release changes from polyox matrices (PEO 301 and 303) when stored at 40?C. The effect of different types of fillers (lactose, mannitol and dicalcium phosphate dihydrate) on stability of diltiazem HCl release profiles was also investigated. Generally, the presence of sodium metabisulfite stabilized the release of drug from PEO matrices stored at 40?C for 8 weeks. Whilst the absence of metabisulfite caused an increase in drug release from polyox matrices when stored at 40?C. The results indicate that all three concentrations (0.25, 0.5 and 1% w/w) of sodium metabisulfite were able to overcome structural changes of polyox samples hence stabilizing the drug release. The results also showed that the incorporation of fillers in polyox matrices reduced the sensitivity of drug release when stored at elevated temperature. This indicates that when these excipients were used there was no need to incorporate additional antioxidant. DSC results showed that there was no difference in the melting points of fresh polyox samples and aged polyox samples containing sodium metabisulfite, whereas the melting point of aged polyox samples without sodium metabisulfite were lower than fresh polyox samples. This indicates that the presence of metabisulfite is essential to stabilize polyox samples. PMID:23962147

  2. Design and evaluation of polyox and pluronic controlled gastroretentive delivery of troxipide.

    PubMed

    Jagdale, Swati C; Kamble, Shraddha B; Kuchekar, Bhanudas S; Chabukswar, Aniruddha R

    2014-01-01

    Objective. Objective of the present work was to develop site-specific gastroretentive drug delivery of Troxipide using polymers Pluronic F127 and Polyox 205 WSR. Troxipide is a novel gastroprotective agent with antiulcer, anti-inflammatory, and mucus secreting properties with elimination half-life of 7.4 hrs. Troxipide inhibits H. pylori-derived urease. It is mainly absorbed from stomach. Methods. 3(2) factorial design was applied to study the effect of independent variable. Effects of concentration of polymer on dependant variables as swelling index, hardness, and % drug release were studied. Pluronic F127 and Polyox 205 WSR were used as rate controlled polymer. Sodium bicarbonate and citric acid were used as effervescent-generating agent. Results. From the factorial batches, it was observed that formulation F5 (19% Pluronic F127 and 80% Polyox 205 WSR) showed optimum controlled drug release (98.60% ± 1.82) for 10 hrs with ability to float >12 hrs. Optimized formulation characterized by FTIR and DSC studies confirmed no chemical interactions between drug and polymer. Gastroretention for 6 hrs for optimized formulations was confirmed by in vivo X-ray placebo study. Conclusion. Results demonstrated feasibility of Troxipide in the development of gastroretentive site-specific drug delivery. PMID:25505995

  3. Design and Evaluation of Polyox and Pluronic Controlled Gastroretentive Delivery of Troxipide

    PubMed Central

    Jagdale, Swati C.; Kamble, Shraddha B.; Kuchekar, Bhanudas S.; Chabukswar, Aniruddha R.

    2014-01-01

    Objective. Objective of the present work was to develop site-specific gastroretentive drug delivery of Troxipide using polymers Pluronic F127 and Polyox 205 WSR. Troxipide is a novel gastroprotective agent with antiulcer, anti-inflammatory, and mucus secreting properties with elimination half-life of 7.4 hrs. Troxipide inhibits H. pylori-derived urease. It is mainly absorbed from stomach. Methods. 32 factorial design was applied to study the effect of independent variable. Effects of concentration of polymer on dependant variables as swelling index, hardness, and % drug release were studied. Pluronic F127 and Polyox 205 WSR were used as rate controlled polymer. Sodium bicarbonate and citric acid were used as effervescent-generating agent. Results. From the factorial batches, it was observed that formulation F5 (19% Pluronic F127 and 80% Polyox 205 WSR) showed optimum controlled drug release (98.60% ± 1.82) for 10 hrs with ability to float >12 hrs. Optimized formulation characterized by FTIR and DSC studies confirmed no chemical interactions between drug and polymer. Gastroretention for 6 hrs for optimized formulations was confirmed by in vivo X-ray placebo study. Conclusion. Results demonstrated feasibility of Troxipide in the development of gastroretentive site-specific drug delivery. PMID:25505995

  4. Application of Design of Experiment for Polyox and Xanthan Gum Coated Floating Pulsatile Delivery of Sumatriptan Succinate in Migraine Treatment

    PubMed Central

    Jagdale, Swati C.; Pawar, Chandrakala R.

    2014-01-01

    Migraine follows circadian rhythm in which headache is more painful at the awakening time. This needs administration of dosage form at night time to release drug after lag period when pain gets worse. Sumatriptan succinate is a drug of choice for migraine. Sumatriptan succinate has bitter taste, low oral bioavailability, and shorter half-life. Present work deals with application of design of experiment for polyox and xanthan gum in development of press coated floating pulsatile tablet. Floating pulsatile concept was applied to increase gastric residence of the dosage form. Burst release was achieved through immediate release tablet using crospovidone as superdisintegrant (10%). Pulse lag time was achieved using swellable polymer polyox WSR 205 and xanthan gum. 32 experimental design was applied. Optimized formulation was evaluated for physical characteristics and in-vitro and in-vivo study. From results, it can be concluded that optimized batch F8 containing polyox WSR205 (72.72%) and xanthan gum (27.27%) of total weight of polymer has shown floating lag time of 55 ± 2 sec, drug content of 100.35 ± 0.4%, hardness of 6 ± 0.1 Kg/cm2, and 98.69 ± 2% drug release in pulse manner with lag time of 7 ± 0.1 h. Optimized batch showed prolong gastric residence which was confirmed by in-vivo X-ray study. PMID:25530963

  5. Application of design of experiment for polyox and xanthan gum coated floating pulsatile delivery of sumatriptan succinate in migraine treatment.

    PubMed

    Jagdale, Swati C; Pawar, Chandrakala R

    2014-01-01

    Migraine follows circadian rhythm in which headache is more painful at the awakening time. This needs administration of dosage form at night time to release drug after lag period when pain gets worse. Sumatriptan succinate is a drug of choice for migraine. Sumatriptan succinate has bitter taste, low oral bioavailability, and shorter half-life. Present work deals with application of design of experiment for polyox and xanthan gum in development of press coated floating pulsatile tablet. Floating pulsatile concept was applied to increase gastric residence of the dosage form. Burst release was achieved through immediate release tablet using crospovidone as superdisintegrant (10%). Pulse lag time was achieved using swellable polymer polyox WSR 205 and xanthan gum. 3(2) experimental design was applied. Optimized formulation was evaluated for physical characteristics and in-vitro and in-vivo study. From results, it can be concluded that optimized batch F8 containing polyox WSR205 (72.72%) and xanthan gum (27.27%) of total weight of polymer has shown floating lag time of 55 ± 2 sec, drug content of 100.35 ± 0.4%, hardness of 6 ± 0.1 Kg/cm(2), and 98.69 ± 2% drug release in pulse manner with lag time of 7 ± 0.1 h. Optimized batch showed prolong gastric residence which was confirmed by in-vivo X-ray study. PMID:25530963

  6. An Investigation on the Effect of Polyethylene Oxide Concentration and Particle Size in Modulating Theophylline Release from Tablet Matrices.

    PubMed

    Shojaee, Saeed; Emami, Parastou; Mahmood, Ahmad; Rowaiye, Yemisi; Dukulay, Alusine; Kaialy, Waseem; Cumming, Iain; Nokhodchi, Ali

    2015-12-01

    Polyethylene oxide has been researched extensively as an alternative polymer to hydroxypropyl methylcellulose (HPMC) in controlled drug delivery due to its desirable swelling properties and its availability in a number of different viscosity grades. Previous studies on HPMC have pointed out the importance of particle size on drug release, but as of yet, no studies have investigated the effect of particle size of polyethylene oxide (polyox) on drug release. The present study explored the relationship between polymer level and particle size to sustain the drug release. Tablets produced contained theophylline as their active ingredient and consisted of different polyethylene oxide particle size fractions (20-45, 45-90, 90-180 and 180-425 μm). It was shown that matrices containing smaller particle sizes of polyox produced harder tablets than when larger polyox particles were used. The release studies showed that matrices consisting of large polyox particles showed a faster release rate than matrices made from smaller particles. Molecular weight (MW) of the polymer was a key determining step in attaining sustained release, with the high MW of polyox resulting in a delayed release profile. The results showed that the effect of particle size on drug release was more detrimental when a low concentration of polyox was used. This indicates that care must be taken when low levels of polyox with different particle size fractions are used. More robust formulations could be obtained when the concentration of polyox is high. Differential scanning calorimetry (DSC) traces showed that particle size had no major effect on the thermal behaviour of polyox particles. PMID:25771738

  7. Designing of the Mucoadhesive Intravaginal Spermicidal Films

    PubMed Central

    Kawarkhe, Shilpa; Poddar, S. S.

    2010-01-01

    A mucoadhesive drug delivery system for local delivery of metronidazole through vaginal route was formulated. Films were prepared by solvent evaporation method using various compositions of Carbopol, hydroxypropylmethylcellulose, chitosan, Polyox and propylene glycol. The films were evaluated for their weight, thickness, surface pH, folding endurance, mechanical, drug content uniformity, in vitro drug release, swelling, gelling and mucoadhesion property. All the films possess satisfactory film characteristics. Films made of Polyox found to possess acceptable, physicochemical, mechanical, gelling and mucoadhesion property for delivery of metronidazole. PMID:21695003

  8. Optimization Studies on Compression Coated Floating-Pulsatile Drug Delivery of Bisoprolol

    PubMed Central

    Jagdale, Swati C.; Bari, Nilesh A.; Kuchekar, Bhanudas S.; Chabukswar, Aniruddha R.

    2013-01-01

    The purpose of the present work was to design and optimize compression coated floating pulsatile drug delivery systems of bisoprolol. Floating pulsatile concept was applied to increase the gastric residence of the dosage form having lag phase followed by a burst release. The prepared system consisted of two parts: a core tablet containing the active ingredient and an erodible outer shell with gas generating agent. The rapid release core tablet (RRCT) was prepared by using superdisintegrants with active ingredient. Press coating of optimized RRCT was done by polymer. A 32 full factorial design was used for optimization. The amount of Polyox WSR205 and Polyox WSR N12K was selected as independent variables. Lag period, drug release, and swelling index were selected as dependent variables. Floating pulsatile release formulation (FPRT) F13 at level 0 (55?mg) for Polyox WSR205 and level +1 (65?mg) for Polyox WSR N12K showed lag time of 4?h with >90% drug release. The data were statistically analyzed using ANOVA, and P < 0.05 was statistically significant. Release kinetics of the optimized formulation best fitted the zero order model. In vivo study confirms burst effect at 4?h in indicating the optimization of the dosage form. PMID:24367788

  9. An experimental study of non-Newtonian polymer rheology effects on oil recovery and injectivity

    SciTech Connect

    Gleasure, R.W.; Phillips, C.R. )

    1990-11-01

    Pseudoplastic non-Newtonian polymer solutions were examined for their enhanced oil recovery performance. Detailed results are reported for xanthan gum (XAN), Kelzan XCD, and a viscoelastic polyethylene oxide (PEO), Polyox OF-50. Increases in the power-law coefficient resulted in improved displacement efficiency. Effects were also observed in the injectivity-index parameter results.

  10. 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

  11. Screening and degradation tests of linear-polymer additives for district heating applications

    SciTech Connect

    Choi, U.S.; Cho, Y.I.; Kasza, K.E.

    1987-12-01

    In closed-loop district heating and cooling (DHC) systems, the addition of a friction-reducing additive to the working fluid conveying energy between the energy sources and end users would allow increased load-handling capability (in an existing system) or the use of much smaller pipes and/or pumps (in a new system). As the first step in identifying friction-reducing additives that have a reasonable lifetime at DHC tempratures, two high-molecular-weight linear-polymer additives have been tested at two different temperatures (25.0/sup 0/C and 87.8/sup 0/C). The additives are Polyox WSR-301 and Separan AP-273 at 200 wppm in deionized water. Results of capillary tube screening tests with fresh solutions show that both polymers can give more than 60% friction reduction. However, Separan is effective at high temperatures, whereas Polyox undergoes thermal degradation. Degradation tests in a closed recirculatory flow system show that (1) friction reduction is always accompanied by heat transfer reduction regardless of the hours of shear, (2) Polyox cannot be uwsed in recirculatory systems because it is very sensitive to mechanical degradation, and (3) although Separan does degrade under high flow shear conditions, it does not degrade completely; it achieves a plateau value of friction reduction even under conditnuous shear. This is an important discovery and implies that Separan is still a good candidate for closed-loop DH systems. 36 refs., 12 figs., 1 tab.

  12. Investigating the cubosomal ability for transnasal brain targeting: In vitro optimization, ex vivo permeation and in vivo biodistribution.

    PubMed

    Abdelrahman, Fatma Elzahraa; Elsayed, Ibrahim; Gad, Mary Kamal; Badr, Ahmed; Mohamed, Magdi Ibrahim

    2015-07-25

    The aim of this study was to enhance the risperidone delivery to the brain through the transnasal route via optimization of cubosomal gel. Cubosomes were prepared using glycerol mono-oleate (GMO), Pluronic F127 (PF127) and Tween 80 (T80). The prepared formulae were characterized by testing their particle size, polydispersity index, zeta potential, entrapment efficiency, in vitro drug release and transmission electron microscopy. Central composite design was planned for the formulae optimization and the selected formula (containing PF127 with concentration 15 mg/g GMO and T80 with concentration of 20mg/L) was re-prepared in presence of gelling polymer (gellan gum or polyox). The optimal cubosomal gel (containing 0.4% w/v polyox) had been subjected to ex-vivo permeation, histopathological evaluation and in vivo biodistribution studies. It showed significantly higher transnasal permeation and better distribution to the brain, when compared to the used control (drug solution and/or suspension). Finally, the cubosomal gel could be considered as a promising carrier for brain targeting of CNS acting drugs through the transnasal route. PMID:26026251

  13. Formulation Optimization of Hot Melt Extruded Abuse Deterrent Pellet Dosage Form Utilizing Design of Experiments (DOE)

    PubMed Central

    Maddineni, Sindhuri; Battu, Sunil Kumar; Morott, Joe; Majumdar, Soumyajit; Repka, Michael A.

    2014-01-01

    The objective of the present study was to develop techniques for an abuse-deterrent (AD) platform utilizing hot melt extrusion (HME) process. Formulation optimization was accomplished by utilizing Box-Behnken design of experiments to determine the effect of the three formulation factors: PolyOx WSR301, Benecel K15M, and Carbopol 71G; each of which was studied at three levels on TR attributes of the produced melt extruded pellets. A response surface methodology was utilized to identify the optimized formulation. Lidocaine Hydrochloride was used as a model drug, and suitable formulation ingredients were employed as carrier matrices and processing aids. All of the formulations were evaluated for the TR attributes such as particle size post-milling, gelling, percentage of drug extraction in water and alcohol. All of the DOE formulations demonstrated sufficient hardness and elasticity, and could not be reduced into fine particles (<150m), which is a desirable feature to prevent snorting. In addition, all of the formulations exhibited good gelling tendency in water with minimal extraction of drug in the aqueous medium. Moreover, Benecel K15M in combination with PolyOx WSR301 could be utilized to produce pellets with TR potential. HME has been demonstrated to be a viable technique with a potential to develop novel abuse-deterrent formulations. PMID:24433429

  14. Particle-laden tubeless siphon

    NASA Astrophysics Data System (ADS)

    Joseph, Daniel; Wang, Jing

    2003-11-01

    A tubeless siphon was created by sucking a 1% aqueous Polyox(Polyox is a registered trademark of Union Carbide.) solution laden with particles from a beaker into a cylinder by a moving piston. The piston speed and particle concentration were varied. At very high rates of withdrawal, all the fluid could be removed before the siphon broke. In this case, the beaker was completely cleaned without a trace of liquid. The addition of small concentrations of small, nearly neutrally buoyant particles greatly enhanced the pulling power of the liquid, reducing the threshold speed of withdrawal at which the beaker was completely cleaned. At speeds of withdrawal smaller than the threshold not all of the fluid-particle mixture is pulled out of the beaker. The amount pulled out first increases, then decreases as the particle concentration is increased. We present an argument, based on viscoelastic potential flow, that the enhancement of the effective extensional stress is due to the reversal of the sign of the normal stresses at stagnation points on the particles.

  15. Development and optimization of press coated floating pulsatile drug delivery of sumatriptan succinate.

    PubMed

    Jagdale, Swati C; Pawar, Chandrakala R

    2014-01-01

    Floating pulsatile is combined approach designed according to circadian rhythm to deliver the drug at right time, in right quantity and at right site as per pathophysiological need of disease with prolong gastric residence and lag phase followed by burst release. As the migraine follows circadian rhythm in which headache is more painful at the awakening time, the dosage form should be given during night time to release drug when pain get worsen. Present work deals with formulation and optimization of floating pulsatile tablet of sumatriptan succinate. Core tablet containing crospovidone as superdisintegrant (10%) showed burst release. Lag time was maintained using swellable polymer as polyoxN12K and xanthum gum. 3(2) experimental design was carried out. Developed formulations were evaluated for physical characteristics, in vitro and in vivo study. Optimized batch F2 with concentration of polyox N12K (73.43%) and xanthum gum (26.56%) of total polymer weight showed floating lag time 15±2 sec, drug content 99.58±0.2 %, hardness 6±0.2 Kg/cm(2) and drug release 99.54±2% with pulsatile manner followed lag period of 7±0.1h. In vivo x-ray study confirms prolong gastric residence of system. Programmable pulsatile release has been achieved by formulation F2 which meet demand of chronotherapeutic objective of migraine. PMID:24893996

  16. Polymer drag reduction in large diameter coal log pipeline

    SciTech Connect

    Wu, Gangwei; Miles, J.; Xu, Jihuai

    1998-04-01

    A hydraulic capsule pipeline (HCP) drag reduction study is being conducted using a 210 mm inner diameter, 131 m long steel pipe loop located at the Research Park of the University of Missouri-Columbia (UMC). Polyox (trade name for polyethylene oxide) was tested alone and in combination with fiber for the first time for drag reduction investigations in such a large diameter HCP flow. A novel design of vacuum-aided Polyox dissolution and injection system was also tested for the first time in this pipeline. The injected polymer concentration present was determined on the basis of average concentration over the entire pipeline loop. Subsequently, more detailed data reduction will be presented based upon local polymer concentration in the test section determined by a dispersion model, which is being developed and will be calibrated to the experimental system using a fluorescent dye additive for experimental measurement. In addition, abrasion-resistant resin logs with cement additives for density control were employed to simulate coal logs. Results of this study not only answered some basic questions about drag reduction in HCP flow, it is also beneficial and important to HCP commercial applications.

  17. Polymer drag reduction in large diameter coal log pipeline

    SciTech Connect

    Wu, G.; Xu, J. Miles, J.

    1998-07-01

    A hydraulic capsule pipeline (HCP) drag reduction study is being conducted using a 210 mm inner diameter, 131 m long steel pipe loop located at the Research Park of the University of Missouri-Columbia (UMC). Polyox (trade name for polyethylene oxide) was tested alone and in combination with fiber for the first time for drag reduction investigations in such a large diameter HCP flow. A novel design of vacuum-aided Polyox dissolution and injection system was also tested for the first time in this pipeline. The injected polymer concentration present was determined on the basis of average concentration over the entire pipeline loop. Subsequently, more detailed data reduction will be presented based upon local polymer concentration in the test section determined by a dispersion model, which is being developed and will be calibrated to the experimental system using a fluorescent dye additive for experimental measurement. In addition, abrasion-resistant resin logs with cement additives for density control were employed to simulate coal logs. Results of this study not only answered some basic questions about drag reduction in HCP flow, it is also beneficial and important to HCP commercial applications.

  18. Design and in vitro evaluation of a novel vaginal drug delivery system based on gelucire.

    PubMed

    Geeta, M Patel; Madhabhai, M Patel

    2009-04-01

    Carbamazepine indicated for the control of epilepsy, undergoes extensive hepatic first-pass metabolism after oral administration. A vaginal dosage form of carbamazepine is not commercially available. Conventional suppository having poor retention in the vaginal tract, as they are removed in a short time by the tract's self-cleansing action, having poor patient compliance. To overcome such problems, delivery system with mucoadhesive polymers polyox WSR N-60K and Ucarflock 302 that prolong drug permanence on the vaginal mucosa were developed. In the present study the suitability of gelucires to formulate vaginal pesseries was investigated. The possible modification of carbamazepine release kinetics by using gelucires blends and hydrophilic additives in the pesseries was evaluated. It was observed that among gelucire grades melting point higher than 37 degrees C, the release rate proved to be highly dependant on HLB value and matrix composition. In most of the formulations carbamazepine release occurred by disintegration and erosion of the matrices which is depending upon the vehicle employed. The aging study revealed that the formulations containing G50/13 and G50/13-G44/14 blends undergo some changes during one year of shelf aging. From the results obtained it can be concluded that different gelucire grades and their blends along with hydrophilic polymer could be successesively used to formulate prolong release carbamazepine pesseries. PMID:19450222

  19. A novel bi-layer ascending release osmotic pump tablet: in vitro investigation and in vivo investigation in pharmacokinetic study and IVIVC evaluation.

    PubMed

    Xu, Heming; Li, Zhao; Pan, Hao; Zhang, Zhihong; Liu, Dandan; Tian, Baocheng; Ma, Shilin; Song, Shilong; Pan, Weisan

    2013-12-15

    This study was aimed to develop an ascending release push-pull osmotic pump (APOP) system with a novel mechanism and an easy manufacture process. Theoretical analysis showed that the key to obtain the non-zero order drug release was to break the balance between the drug suspension release rate in the drug layer and the swelling rate of the core, and an ascending drug release rate was achieved when the former was slower than the latter. A polymer (Polyox WSR N-12K) was introduced as a suspension agent in drug layer to slow down the hydration rate of drug layer. Influence of the composition of drug layer (PEO category, total amount, drug loading and fraction of NaCl), push layer (NaCl amount), and also the level of coating weight gain on the drug release profiles was investigated. Observation of hydration state was estimated by taking photos, and also was confirmed by the theories. Paliperidone was delivered successfully by APOP at an ascending release rate up to 20 h in vitro. The in vivo plasma concentration of paliperidone in beagle dogs increased gradually up to 19 h. The APOP with an easy manufacture process was a promising strategy to deliver drug at an ascending rate. PMID:24095815

  20. Design and development of polyethylene oxide based matrix tablets for verapamil hydrochloride.

    PubMed

    Vidyadhara, S; Sasidhar, R L C; Nagaraju, R

    2013-03-01

    In the present investigation an attempt has been made to increase therapeutic efficacy, reduced frequency of administration and improved patient compliance by developing controlled release matrix tablets of verapamil hydrochloride. Verapamil hydrochloride was formulated as oral controlled release matrix tablets by using the polyethylene oxides (Polyox WSR 303). The aim of this study was to investigate the influence of polymer level and type of fillers namely lactose (soluble filler), swellable filler (starch 1500), microcrystalline cellulose and dibasic calcium phosphate (insoluble fillers) on the release rate and mechanism of release for verapamil hydrochloride from matrix tablets prepared by direct compression process. Higher polymeric content in the matrix decreased the release rate of drug. On the other hand, replacement of lactose with anhydrous dibasic calcium phosphate and microcrystalline cellulose has significantly retarded the release rate of verapamil hydrochloride. Biopharmaceutical evaluation of satisfactory formulations were also carried out on New Zealand rabbits and parameters such as maximum plasma concentration, time to reach peak plasma concentration, area under the plasma concentration time curve(0-t) and area under first moment curve(0-t) were determined. In vivo pharmacokinetic study proves that the verapamil hydrochloride from matrix tablets showed prolonged release and were be able to sustain the therapeutic effect up to 24 h. PMID:24019567

  1. Coal log pipeline pilot plant study

    SciTech Connect

    Liu, H.; Lenau, C.W.; Burkett, W.

    2000-07-01

    After 8 years of extensive R and D in the new technology of coal log pipeline (CLP), a pilot plant is being built to demonstrate and test a complete CLP system for coal transportation. The system consists of a coal log fabrication plant, a 3,000-ft-length, 6-inch-diameter underground pipeline loop to transport 5.4-inch diameter coal logs, a log injection/ejection system, a pump bypass, a reservoir that serves as both the intake and the outlet of the CLP systems, an instrumentation system that includes pressure transducers, coal log sensors, and flowmeters, and an automatic control system that includes PLCs and a central computer. The pilot plant is to be completed in May of Year 2000. Upon completion of construction, the pilot plant will be used for running various types of coal, testing the degradation rate of drag reduction in CLP using Polyox (polyethylene oxide), testing the reliability of a special coal log sensor invented at the University of Missouri, testing the reliability and the efficiency of the pump-bypass system for pumping coal log trains through the pipe, and testing various hardware components and software for operating the pilot plant. Data collected from the tests will be used for designing future commercial systems of CLP. The pilot plant experiments are to be completed in two years. Then, the technology of CLP will be ready for commercial use.

  2. Two different approaches for the prediction of in vivo plasma concentration-time profile from in vitro release data of once daily formulations of diltiazem hydrochloride.

    PubMed

    Bendas, Ehab R

    2009-09-01

    The aim of this study was to employ two different mathematical approaches: first, a convolution approach using computer software; second, a mathematical calculation exploiting Wagner-Nelson calculation to predict in vivo plasma concentration-time profile from the in vitro release study for the once daily formulations of a model drug diltiazem hydrochloride. The once daily extended release tablets (120 mg) were prepared by the wet granulation technique. Ethanol or ethanolic solutions of ethylcellulose (N22), were used as granulating agents along with hydrophilic matrix polymers like hydroxypropyl methylcellulose (HPMC) (K 15M). The granules showed satisfactory flow properties, compressibility, moisture content and drug content. All the tablet formulations showed acceptable properties and complied with pharmacopeial limits. The in vitro drug release study revealed that formula F7-T which contains drug: HPMC ratio 1:1 and 20 mg of ethylcellulose was able to sustain the drug release for 24 h and satisfied the USP dissolution limits. Fitting the in vitro drug release data to Korsmeyer-Peppas equation indicated that the mechanism of drug release could be zero-order. The capsule formulation F14-C which consists of drug: HPMC ratio 1:2, 12 mg of ethylcellulose and 20 mg of polyox 100 showed in vitro drug release similar to the tablet F7-T using the similarity factor (f 2). The mechanism of drug release could be coupled diffusion, and polymer matrix relaxation. The percent dissolved data from the two formulations were used as input function to predict the in vivo plasma data by the two approaches (Convolution by Kinetica software and Wagner-Nelson calculation). The two methods were validated by prediction of plasma data from in vitro release data of FDA approved 300 mg extended release capsule. Prediction errors were estimated for Cmax and area under the curve (AUC) to determine the validity of the methods. The percent prediction error for each parameter is not exceeding 15%. PMID:19784589

  3. Influence of Plasticizers on the Stability and Release of a Prodrug of ?9-Tetrahydrocannabinol Incorporated in Poly (Ethylene Oxide) Matrices

    PubMed Central

    Thumma, Sridhar; ElSohly, Mahmoud A.; Zhang, Shuang-Qing; Gul, Waseem; Repka, Michael A.

    2008-01-01

    The objective of the present research was to stabilize a heat-labile novel prodrug of ?9-tetrahydrocannabinol (THC), THC-hemiglutarate (THC-HG), in polyethylene oxide (PEO) [PolyOx WSR N-80 (PEO N-80), MW 200,000 Daltons] polymeric matrix systems produced by hot-melt fabrication for systemic delivery of THC through the oral transmucosal route. For this purpose, the effects of processing conditions (processing temperature and heating duration), plasticizer type and concentration and storage conditions on the stability of the prodrug were investigated. The selected plasticizers studied included vitamin E succinate (VES), acetyltributyl citrate (ATBC), triethyl citrate (TEC), triacetin and polyethylene glycol 8000 (PEG 8000). Furthermore, the influence of plasticizer concentration on drug release was also studied. The stability of THC-HG in PEO matrices was influenced by all of the aforementioned variables. Films processed at 110 C for 7 min were found to be favorable for hot-melt processing with a post- processing drug content of 95%, while significant degradation of THC-HG (~42%) was observed in those processed at 200 C for 15 min. The degradation of the prodrug during hot-melt fabrication and also upon storage was considerably reduced in the presence of the plasticizers investigated, VES being the most effective. Modulation of the microenvironmental pH to an acidic range via incorporation of citric acid in PEO-plasticizer matrices significantly improved the stability of the prodrug, with almost 90% of the theoretical drug remaining as opposed to only 15% remaining in PEO-only matrices when stored at 40 C for up to 3 months. The release of drug from PEO matrices was influenced both by the plasticizer type and concentration. A faster release resulted from water-soluble plasticizers, PEG 8000 and triacetin, and with increasing concentration. However, a slower release was observed with an increase in concentration of water-insoluble plasticizers, VES and ATBC. PMID:18602993