Sample records for non-ionic water-soluble contrast

  1. Diagnostic image quality of hysterosalpingography: ionic versus non ionic water soluble iodinated contrast media

    PubMed Central

    Mohd Nor, H; Jayapragasam, KJ; Abdullah, BJJ


    Objective To compare the diagnostic image quality between three different water soluble iodinated contrast media in hysterosalpingography (HSG). Material and method In a prospective randomised study of 204 patients, the diagnostic quality of images obtained after hysterosalpingography were evaluated using Iopramide (106 patients) and Ioxaglate (98 patients). 114 patients who had undergone HSG examination using Iodamide were analysed retrospectively. Image quality was assessed by three radiologists independently based on an objective set of criteria. The obtained results were statistically analysed using Kruskal-Wallis and Mann-Whitney U test. Results Visualisation of fimbrial rugae was significantly better with Iopramide and Ioxaglate than Iodamide. All contrast media provided acceptable diagnostic image quality with regard to uterine, fallopian tubes outline and peritoneal spill. Uterine opacification was noted to be too dense in all three contrast media and not optimal for the assessment of intrauterine pathology. Higher incidence of contrast intravasation was noted in the Iodamide group. Similarly, the numbers of patients diagnosed with bilateral blocked fallopian tubes were also higher in the Iodamide group. Conclusion HSG using low osmolar contrast media (Iopramide and Ioxaglate) demonstrated diagnostic image qualities similar to HSG using conventional high osmolar contrast media (Iodamide). However, all three contrast media were found to be too dense for the detection of intrauterine pathology. Better visualisation of the fimbrial outline using Ioxaglate and Iopramide were attributed to their low contrast viscosity. The increased incidence of contrast media intravasation and bilateral tubal blockage using Iodamide are probably related to the high viscosity. PMID:21611058

  2. A non-ionic water-soluble seed gum from Ipomoea campanulata.


    Singh, V; Pandey, M; Srivastava, A; Sethi, R


    A non-ionic water-soluble galactomannan, having galactose and mannose in 2:3 molar ratio was isolated from endosperm of the seeds of Ipomoea campanulata. The seed gum was found to have linear chain of beta (1-->4) linked mannopyranosyl units with D-galactose side chains attached through alpha (1-->6) linkage to the main chain. This structure is similar to many commercial gums like Guar, Carob and Locust bean gum. Various physical properties of the gum were studied in order to explore the possibility of commercial exploitation of the seed gum. PMID:12628393

  3. Torsten Almén (1931-2016): the father of non-ionic iodine contrast media.


    Nyman, Ulf; Ekberg, Olle; Aspelin, Peter


    The Swedish radiologist Torsten Almén is the first clinical radiologist ever to have made a fundamental contribution to intravascular contrast medium design, the development of non-ionic contrast media. He became emotionally triggered by the patients' severe pain each time he injected the ionic "high-osmolar" contrast media when performing peripheral arteriographies in the early 1960s. One day he got a flash of genius that combined the observation of pain, a pathophysiological theory and how to eliminate it with suitable contrast media chemistry. After self-studies in chemistry he developed the concept of iodine contrast media not dissociating into ions in solution to reduce their osmolality and even reach plasma isotonicity. He offered several pharmaceutical companies his concept of mono- and polymeric non-ionic agents but without response, since it was considered against the chemical laws of that time. Contrast media constructed as salts and dissociating into ions in solution was regarded an absolute necessity to achieve high enough water solubility and concentration for diagnostic purposes. Finally a small Norwegian company, Nyegaard & Co., took up his idea 1968 and together they developed the essentially painless "low-osmolar" monomeric non-ionic metrizamide (Amipaque) released in 1974 and iohexol (Omipaque) in 1982 followed by the "iso-osmolar" dimeric non-ionic iodixanol (Visipaque) released in 1993. This has implied a profound paradigm shift with regard to reduction of both hypertonic and chemotoxic side effects, which have been a prerequisite for the today's widespread use of contrast medium-enhanced CT and advanced endovascular interventional techniques even in fragile patients. PMID:27225455

  4. The size and shape of three water-soluble, non-ionic polysaccharides produced by lactic acid bacteria: A comparative study.


    Dalheim, Marianne Øksnes; Arnfinnsdottir, Nina Bjørk; Widmalm, Göran; Christensen, Bjørn E


    Three water-soluble, non-ionic extracellular polysaccharides (EPS) obtained from lactic acid bacteria (S. thermophilus THS, L. helveticus K16 and S. thermophilus ST1) were subjected to a comparative study by means of multidetector size-exclusion chromatography, providing distributions and averages of molar masses, radii of gyration and intrinsic viscosities. All polysaccharides displayed random coil character. Further analysis of the data reveals differences in chain stiffness and extension that could be well correlated to structural features. The calculated persistence lengths ranged from 5 to 10nm and fall within the range typical for many single-stranded bacterial or plant polysaccharides. The ST1 polysaccharide had the highest molar mass but the lowest persistence length, which is attributed to the presence of the flexible (1→6)-linkage in the main chain. PMID:26917378

  5. Ex vivo micro-CT imaging of murine brain models using non-ionic iodinated contrast

    NASA Astrophysics Data System (ADS)

    Salas Bautista, N.; Martínez-Dávalos, A.; Rodríguez-Villafuerte, M.; Murrieta-Rodríguez, T.; Manjarrez-Marmolejo, J.; Franco-Pérez, J.; Calvillo-Velasco, M. E.


    Preclinical investigation of brain tumors is frequently carried out by means of intracranial implantation of brain tumor xenografts or allografts, with subsequent analysis of tumor growth using conventional histopathology. However, very little has been reported on the use contrast-enhanced techniques in micro-CT imaging for the study of malignant brain tumors in small animal models. The aim of this study has been to test a protocol for ex vivo imaging of murine brain models of glioblastoma multiforme (GBM) after treatment with non-ionic iodinated solution, using an in-house developed laboratory micro-CT. We have found that the best compromise between acquisition time and image quality is obtained using a 50 kVp, 0.5 mAs, 1° angular step on a 360 degree orbit acquisition protocol, with 70 μm reconstructed voxel size using the Feldkamp algorithm. With this parameters up to 4 murine brains can be scanned in tandem in less than 15 minutes. Image segmentation and analysis of three sample brains allowed identifying tumor volumes as small as 0.4 mm3.

  6. [General pharmacological study of iodixanol, a new non-ionic isotonic contrast medium].


    Takasuna, K; Kasai, Y; Kitano, Y; Mori, K; Kobayashi, R; Makino, M; Hagiwara, T; Hirohashi, M; Nomura, M; Algate, D R


    The general pharmacological study of iodixanol, a non-ionic isotonic contrast medium, was conducted. 1) Iodixanol administered intravenously over a dose range of 320 to 3,200 mgI/kg had little or no effect on the general behavior, spontaneous locomotor activity, hexobarbital sleeping time, pain response, electroshock- or pentylenetetrazol-induced convulsion (mouse), EEG or body temperature (rabbit), gastrointestinal propulsion (mouse) or skeletal muscle contraction (rabbit). Iodixanol had no specific interaction with acetylcholine, histamine, serotonin, nicotin, BaCl2 (ileum), methacholine (trachea), isoprenaline (atrium) or oxytocin (pregnant uterus), nor had any effect on spontaneous contractility (atrium and uterus), or transmural electrostimulation-induced contractility (vas deferens) at concentrations of < or = 3.2 x 10(-3) gI/ml in vitro. Iodixanol had no effect on the cardiovascular system of dog, except that it increased femoral blood flow and respiratory rate at doses of > or = 1,000 mgI/kg. Iodixanol at 3,200 mgI/kg i.v. reduced urine output with a decrease in Na+ and Cl- excretion, whereas at 320 mgI/kg i.v., it slightly increased urine output (rat). 2) Injections of iodixanol into the cerebroventricular (0.96, 9.6 mgI/mouse and 3.2, 32 mgI/rat), left ventricular (1,920, 6,400 mgI/dog) or coronary artery (640, 1,920 mgI/dog) had no conspicuous effect on the central nervous system or the cardiovascular system, respectively. There was no marked difference among iodixanol, iohexol and iopamidol in this respect. Vascular pain during injection into the femoral artery (300-320 mgI/guinea pig) appeared to be less intense with iodixanol, compared with the other contrast media iohexol and iopamidol. These results suggest that intravenous injection of iodixanol is relatively free from pharmacological activity, and effects of iodixanol on the central nervous system (intracerebroventricular injection) and cardiovascular system (intra-left ventricular and -coronary

  7. Ventriculography and cisternography with water-soluble contrast media in infants with myelomeningocele

    SciTech Connect

    Yamada, H.; Nakamura, S.; Tanaka, Y.; Tajima, M.; Kageyama, N.


    Fifty-four newborn infants with myelomeningocele and hydrocephalus were studied by ventriculography using water-soluble contrast media; 20 were also studied by metrizamide myeloencephalography and computerized tomographic (CT) cisternography. Ventriculography suggested that the aqueduct was patent in all cases. Outflow of contrast medium from the fourth ventricle was slow in most cases, complete obstruction was seen in 15%, communication was delayed at the outlet in 54%, and rather free communication was observedin 31%. Metrizamide myeloencephalography and CT cisternography suggested a partial block at the level of the ambient cisterns in approximately one-third of infants. These findings support the concept that flow of cerebrospinal fluid is reduced in several areas. Aqueductal stenosis was not considered an important factor in hydrocephalus, while the most important site of obstruction was felt to be the lowest portion of the fourth ventricle.

  8. Water-Soluble Spinel Ferrites by a Modified Polyol Process as Contrast Agents in MRI

    SciTech Connect

    Basina, Georgia; Tzitzios, Vasilis; Niarchos, Dimitris; Li Wanfeng; Khurshid, Hafsa; Hadjipanayis, George; Mao Hui; Hadjipanayis, Costas


    Magnetic nanoparticles have recently been very attractive for biomedical applications. In this study, we have synthesized ferrite nanoparticles for application as contrast agents in MRI experiments. Fe{sub 3}O{sub 4} and MnFe{sub 2}O{sub 4} spinel ferrites with a mean size of 11-12 nm, were prepared by a modified polyol route in commercially available polyethylene glycol with molecular weight 600 (PEG-600). The reaction takes place in the presence of water soluble and non-toxic tri-block copolymer known as Pluronic registered F-127 (PEO{sub 100}-PPO{sub 65}-PEO{sub 100}). The nanoparticles have saturation magnetization values of 52 and 68 emu/g for MnFe{sub 2}O{sub 4} and Fe{sub 3}O{sub 4}, respectively. Both the Fe{sub 3}O{sub 4}, and MnFe{sub 2}O{sub 4} nanoparticles make stable solutions in water known as ferrofluids. Preliminary data demonstrated the capability of these nanoparticles to induce imaging contrast in T{sub 2} weighted MRI experiments, making these materials suitable for biomedical applications such as medical MRI.

  9. Non-ionic contrast media induces oxidative stress and apoptosis through Ca²⁺ influx in human neutrophils.


    Kayan, Mustafa; Nazıroğlu, Mustafa; Ovey, Ishak Suat; Aykur, Mehmet; Uğuz, Abdülhadi Cihangir; Yürekli, Vedat Ali


    Non-ionic contrast media (CM) can induce tissue kidney injury via activation of phagocytosis and oxidative stress, although the mechanisms of injury via neutrophils are not clear. We investigated the effects of CM on oxidative stress and Ca²⁺ concentrations in serum and neutrophils of humans. Ten migraine patients were used in the study. Serum and neutrophil samples from patients' peripheral blood were obtained before (control) and 30 min after non-ionic (iopromide) CM injection. The neutrophils were incubated with non specific transient receptor potential 2 (TRPM2) channel blocker, 2-aminoethoxydiphenyl borate (2-APB), and voltage gated Ca²⁺ channel blockers, verapamil plus diltiazem. Serum and neutrophil lipid peroxidation, apoptosis and intracellular Ca²⁺ concentrations levels were higher in the CM group than in controls. The neutrophilic reduced glutathione (GSH) and glutathione peroxidase (GSH-Px) levels as well as serum vitamin E and β-carotene concentrations were lower in the CM group than in controls. Neutrophil lipid peroxidation levels were lower in the CM+2-APB and CM+verapamil-diltiazem groups than in the CM group, although GSH, GSH-Px and intracellular Ca²⁺ values increased in the CM+2-APB and CM+verapamil-diltiazem groups. However, caspase-3, caspase-9, vitamin A and vitamin C values were unaltered by CM treatment. In conclusion, we observed that CM induced oxidative stress and Ca²⁺ influx by decreasing vitamin E, β-carotene and Ca²⁺ release levels in human serum and neutrophils. However, we observed protective effects of Ca²⁺ channel blockers on Ca²⁺ influx in neutrophils. PMID:22903554

  10. Non-ionic Gd-based MRI contrast agents are optimal for encapsulation into phosphatidyldiglycerol-based thermosensitive liposomes.


    Hossann, Martin; Wang, Tungte; Syunyaeva, Zulfiya; Wiggenhorn, Michael; Zengerle, Anja; Issels, Rolf D; Reiser, Maximilian; Lindner, Lars H; Peller, Michael


    Thermosensitive liposomes (TSL) with encapsulated magnetic resonance imaging (MRI) longitudinal relaxation time (T(1)) contrast agents (CAs) have been proposed for MRI assisted interventional thermotherapy in solid tumors. Here the feasibility of 6 clinically approved CAs (Gd-DTPA, Gd-BOPTA, Gd-DOTA, Gd-BT-DO3A, Gd-DTPA-BMA, and Gd-HP-DO3A) for formulation into TSL was investigated. CAs were passively encapsulated with 323 mOs kg(-1) into 1,2-dipalmitoyl-sn-glycero-3-phosphocholine/1,2-distearoyl-sn-glycero-3-phosphocholine/1,2-dipalmitoyl-sn-glycero-3-phosphodiglycerol 50/20/30 (mol/mol) TSL (DPPG(2)-TSL) to obtain stable formulations. T(1) relaxivity (r(1)) and diffusive permeability to water (P(d)) across the membrane were determined. Shelf life at 4°C was investigated by determining lysolipid content up to 10 weeks after preparation. All preparations were monodispersed with comparable small vesicle sizes (~135 nm). Neither zeta potential nor phase transition temperature (T(m)) was affected by the CA. The formulations showed an increase in r(1) in the temperature range between 38 and 44°C. This correlated with the phase transition. Change in r(1) (Δr(1)=r(1)(45.3°C)-r(1)(37.6°C)) and r(1) (Tnon-ionic Gd-BT-DO3A, Gd-DTPA-BMA, and Gd-HP-DO3A. All CAs except Gd-DTPA-BMA induced phospholipid hydrolysis, which resulted in unwanted CA leakage. The serum proteins HSA and IgG both contributed to the increase of MRI signal at 30°C by increasing P(d). A high concentration of encapsulated CA is a prerequisite to achieve a sufficiently high Δr(1) during heat triggered CA release combined with a low r(1) at 37°C. Hence, the optimal CA is characterized by a non-ionic structure and a low contribution to osmolality. PMID:23246469

  11. Efficient labeling in vitro with non-ionic gadolinium magnetic resonance imaging contrast agent and fluorescent transfection agent in bone marrow stromal cells of neonatal rats.


    Li, Ying-Qin; Tang, Ying; Fu, Rao; Meng, Qiu-Hua; Zhou, Xue; Ling, Ze-Min; Cheng, Xiao; Tian, Su-Wei; Wang, Guo-Jie; Liu, Xue-Guo; Zhou, Li-Hua


    Although studies have been undertaken on gadolinium labeling-based molecular imaging in magnetic resonance imaging (MRI), the use of non-ionic gadolinium in the tracking of stem cells remains uncommon. To investigate the efficiency in tracking of stem cells with non-ionic gadolinium as an MRI contrast agent, a rhodamine-conjugated fluorescent reagent was used to label bone marrow stromal cells (BMSCs) of neonatal rats in vitro, and MRI scanning was undertaken. The fluorescent-conjugated cell uptake reagents were able to deliver gadodiamide into BMSCs, and cell uptake was verified using flow cytometry. In addition, the labeled stem cells with paramagnetic contrast medium remained detectable by an MRI monitor for a minimum of 28 days. The present study suggested that this method can be applied efficiently and safely for the labeling and tracking of bone marrow stromal cells in neonatal rats. PMID:25816076

  12. Efficient labeling in vitro with non-ionic gadolinium magnetic resonance imaging contrast agent and fluorescent transfection agent in bone marrow stromal cells of neonatal rats

    PubMed Central



    Although studies have been undertaken on gadolinium labeling-based molecular imaging in magnetic resonance imaging (MRI), the use of non-ionic gadolinium in the tracking of stem cells remains uncommon. To investigate the efficiency in tracking of stem cells with non-ionic gadolinium as an MRI contrast agent, a rhodamine-conjugated fluorescent reagent was used to label bone marrow stromal cells (BMSCs) of neonatal rats in vitro, and MRI scanning was undertaken. The fluorescent-conjugated cell uptake reagents were able to deliver gadodiamide into BMSCs, and cell uptake was verified using flow cytometry. In addition, the labeled stem cells with paramagnetic contrast medium remained detectable by an MRI monitor for a minimum of 28 days. The present study suggested that this method can be applied efficiently and safely for the labeling and tracking of bone marrow stromal cells in neonatal rats. PMID:25816076

  13. Use of computed tomography-lymphangiography with direct injection of water-soluble contrast medium to identify the origin of chylous ascites.


    Otake, Kohei; Uchida, Keiichi; Inoue, Mikihiro; Koike, Yuhki; Narushima, Mitsunaga; Kusunoki, Masato


    Contrast lymphangiography is a useful technique to determine the site of lymphatic leakage in the patient with chylous ascites. Conventional lymphangiography with lipid-soluble contrast material carries the disadvantage of complications, such as oil emboli and lymphedema. The authors report a successful case of computed tomography (CT)-lymphangiography with direct injection of water-soluble contrast medium into a lower limb lymphatic vessel to determine the site of lymphatic leakage in a pediatric patient with refractory primary chylous ascites. The patient subsequently underwent laparoscopic ligation of the leaking site and recovered well. This novel technique offers superior potential for preoperative assessment and the planning of laparoscopic repair. PMID:26993687

  14. Clinical observation of the adverse drug reactions caused by non-ionic iodinated contrast media: results from 109,255 cases who underwent enhanced CT examination in Chongqing, China

    PubMed Central

    Li, X; Chen, J; Zhang, L; Liu, H; Wang, S; Chen, X; Fang, J; Wang, S


    Objective: To analyse the pattern and factors that influence the incidence of adverse drug reactions (ADRs) induced by non-ionic iodinated contrast media and to evaluate their safety profiles. Methods: Data from 109,255 cases who underwent enhanced CT examination from 1 January 2008 to 31 August 2013 were analysed. ADRs were classified according to the criteria issued by the American College of Radiology and the Chinese Society of Radiology. Results: A total of 375 (0.34%) patients had ADRs, including 281 mild (0.26%); 80 moderate (0.07%); and 14 severe (0.01%) ADRs; no death was found. 302 (80.53%) of the ADRs occurred within 15 min after examination. Patients aged 40–49 years (204 cases, 0.43%; p < 0.01) or who underwent coronary CT angiography (93 cases, 0.61%; p < 0.01) were at a higher risk of ADRs. Female patients (180 cases, 0.40%; p < 0.01) or outpatients had significantly higher incidence rates of ADRs. The symptoms and signs of most of the ADRs were resolved spontaneously within 24 h after appropriate treatment without sequelae. Conclusion: The occurrence of ADRs is caused by the combined effects of multiple factors. The ADRs induced by non-ionic iodinated contrast media are mainly mild ones, while moderate or severe ADRs are relatively rare, suggesting that enhanced CT examination with non-ionic iodinated contrast media is highly safe, and severe adverse events will seldom occur under appropriate care. Advances in knowledge: The study included 109,255 patients enrolled in various types of enhanced CT examinations, which could reflect ADR conditions and regulations in Chinese population accurately and reliably. PMID:25582519

  15. Water-soluble perylenediimides: design concepts and biological applications.


    Sun, Mengmeng; Müllen, Klaus; Yin, Meizhen


    Water-soluble perylenediimides (PDIs) with high fluorescence intensity, photostability and biocompatibility have been successfully prepared and applied in the biological field. In this tutorial review, we briefly focus on the synthetic strategies for the preparation of water-soluble PDIs by incorporating ionic or non-ionic substituents with multiple polar groups into the bay-region, imide- or ortho-positions of PDIs. These ionic/non-ionic substituents can suppress π-π aggregation and shield the inner perylene chromophores, thus contributing to the water solubility which is essential for biological applications. The optical properties, absorption and emission maxima above 500 nm, minimize the autofluorescence background of cells and provide access to imaging in living cells. The biological applications of water-soluble PDIs are discussed from simple (basic) to complex (advanced) processes, including biosensing in vitro studies, imaging and gene/drug delivering in living cells, tissues and the whole body. The promising future of designed multi-functional water-soluble PDIs will be highlighted in this review. PMID:26797049

  16. Developmental and growth controls of tillering and water-soluble carbohydrate accumulation in contrasting wheat (Triticum aestivum L.) genotypes: can we dissect them?

    PubMed Central

    Dreccer, M. Fernanda


    In wheat, tillering and water-soluble carbohydrates (WSCs) in the stem are potential traits for adaptation to different environments and are of interest as targets for selective breeding. This study investigated the observation that a high stem WSC concentration (WSCc) is often related to low tillering. The proposition tested was that stem WSC accumulation is plant density dependent and could be an emergent property of tillering, whether driven by genotype or by environment. A small subset of recombinant inbred lines (RILs) contrasting for tillering was grown at different plant densities or on different sowing dates in multiple field experiments. Both tillering and WSCc were highly influenced by the environment, with a smaller, distinct genotypic component; the genotype×environment range covered 350–750 stems m–2 and 25–210mg g–1 WSCc. Stem WSCc was inversely related to stem number m–2, but genotypic rankings for stem WSCc persisted when RILs were compared at similar stem density. Low tillering–high WSCc RILs had similar leaf area index, larger individual leaves, and stems with larger internode cross-section and wall area when compared with high tillering–low WSCc RILs. The maximum number of stems per plant was positively associated with growth and relative growth rate per plant, tillering rate and duration, and also, in some treatments, with leaf appearance rate and final leaf number. A common threshold of the red:far red ratio (0.39–0.44; standard error of the difference=0.055) coincided with the maximum stem number per plant across genotypes and plant densities, and could be effectively used in crop simulation modelling as a ‘cut-off’ rule for tillering. The relationship between tillering, WSCc, and their component traits, as well as the possible implications for crop simulation and breeding, is discussed. PMID:23213136

  17. Water-soluble vitamins.


    Konings, Erik J M


    Simultaneous Determination of Vitamins.--Klejdus et al. described a simultaneous determination of 10 water- and 10 fat-soluble vitamins in pharmaceutical preparations by liquid chromatography-diode-array detection (LC-DAD). A combined isocratic and linear gradient allowed separation of vitamins in 3 distinct groups: polar, low-polar, and nonpolar. The method was applied to pharmaceutical preparations, fortified powdered drinks, and food samples, for which results were in good agreement with values claimed. Heudi et al. described a separation of 9 water-soluble vitamins by LC-UV. The method was applied for the quantification of vitamins in polyvitaminated premixes used for the fortification of infant nutrition products. The repeatability of the method was evaluated at different concentration levels and coefficients of variation were <6.5%. The concentrations of vitamins found in premixes with the method were comparable to the values declared. A disadvantage of the methods mentioned above is that sample composition has to be known in advance. According to European legislation, for example, foods might be fortified with riboflavin phosphate or thiamin phosphate, vitamers which are not included in the simultaneous separations described. Vitamin B2.--Viñas et al. elaborated an LC analysis of riboflavin vitamers in foods. Vitamin B2 can be found in nature as the free riboflavin, but in most biological materials it occurs predominantly in the form of 2 coenzymes, flavin mononucleotide (FMN) and flavin-adenine dinucleotide (FAD). Several methods usually involve the conversion of these coenzymes into free riboflavin before quantification of total riboflavin. According to the authors, there is growing interest to know flavin composition of foods. The described method separates the individual vitamers isocratically. Accuracy of the method is tested with 2 certified reference materials (CRMs). Vitamin B5.-Methods for the determination of vitamin B5 in foods are limited

  18. Water soluble laser dyes


    Hammond, P.R.; Feeman, J.F.; Field, G.F.


    Novel water soluble dyes of the formula 1 are provided by the formula described in the paper wherein R{sup 1} and R{sup 4} are alkyl of 1 to 4 carbon atoms or hydrogen; or R{sup 1}--R{sup 2} or R{sup 2}--R{sup 4} form part of aliphatic heterocyclic rings; R{sup 2} is hydrogen or joined with R{sup 1} or R{sup 4} as described above; R{sup 3} is --(CH{sub 2}){sub m}--SO{sub 3}{sup {minus}}, where m is 1 to 6; X is N, CH or formula 2 given in paper where Y is 2 --SO{sub 3}{sup {minus}} ; Z is 3, 4, 5 or 6 --SO{sub 3}{sup {minus}}. The novel dyes are particularly useful as the active media in water solution dye lasers.

  19. Water soluble laser dyes


    Hammond, Peter R.; Feeman, James F.; Field, George F.


    Novel water soluble dyes of the formula I are provided ##STR1## wherein R.sup.1 and R.sup.4 are alkyl of 1 to 4 carbon atoms or hydrogen; or R.sup.1 -R.sup.2 or R.sup.2 -R.sup.4 form part of aliphatic heterocyclic rings; R.sup.2 is hydrogen or joined with R.sup.1 or R.sup.4 as described above; R.sup.3 is --(CH.sub.2).sub.m --SO.sub.3.sup.-, where m is 1 to 6; X is N, CH or ##STR2## where Y is 2 --SO.sub.3.sup.- ; Z is 3, 4, 5 or 6 --SO.sub.3.sup.-. The novel dyes are particularly useful as the active media in water solution dye lasers.

  20. Oxidative potential of ambient water-soluble PM2.5 measured by Dithiothreitol (DTT) and Ascorbic Acid (AA) assays in the southeastern United States: contrasts in sources and health associations

    NASA Astrophysics Data System (ADS)

    Fang, T.; Verma, V.; Bates, J. T.; Abrams, J.; Klein, M.; Strickland, M. J.; Sarnat, S. E.; Chang, H. H.; Mulholland, J. A.; Tolbert, P. E.; Russell, A. G.; Weber, R. J.


    The ability of certain components of particulate matter to induce oxidative stress through catalytic generation of reactive oxygen species (ROS) in vivo may be one mechanism accounting for observed linkages between ambient aerosols and adverse health outcomes. A variety of assays have been used to measure this so-called aerosol oxidative potential. We developed a semi-automated system to quantify oxidative potential of filter aqueous extracts utilizing the dithiothreitol (DTT) assay and have recently developed a similar semi-automated system using the ascorbic acid (AA) assay. Approximately 500 PM2.5 filter samples collected in contrasting locations in the southeastern US were analyzed using both assays. We found that water-soluble DTT activity on a per air volume basis was more spatially uniform than water-soluble AA activity. DTT activity was higher in winter than in summer/fall, whereas AA activity was higher in summer/fall compared to winter, with highest levels near highly trafficked highways. DTT activity was correlated with organic and metal species, whereas AA activity was correlated with water-soluble metals (especially water-soluble Cu, r=0.70-0.91 at most sites). Source apportionment models, Positive Matrix Factorization (PMF) and a Chemical Mass Balance Method with ensemble-averaged source impact profiles (CMB-E), suggest a strong contribution from secondary processes (e.g., organic aerosol oxidation or metal mobilization by formation of an aqueous particle with secondary acids) and traffic emissions to both DTT and AA activities in urban Atlanta. Biomass burning was a large source for DTT activity, but insignificant for AA. DTT activity was well correlated with PM2.5 mass (r=0.49-0.86 across sites/seasons), while AA activity did not co-vary strongly with mass. A linear model was developed to estimate DTT and AA activities for the central Atlanta Jefferson Street site, based on the CMB-E sources that are statistically significant with positive

  1. Non-ionic PAG behavior under high energy exposure sources

    NASA Astrophysics Data System (ADS)

    Lawson, Richard A.; Noga, David E.; Tolbert, Laren M.; Henderson, Clifford L.


    A series of non-ionic PAGs were synthesized and their acid generation efficiency measured under deep ultraviolet and electron beam exposures. The acid generation efficiency was determined with an on-wafer method that uses spectroscopic ellipsometry to measure the absorbance of an acid sensitive dye (Coumarin 6). Under DUV exposures, common ionic onium salt PAGs showed excellent photoacid generation efficiency, superior to most non-ionic PAGS tested in this work. In contrast, under 100 keV high energy e-beam exposures, almost all of the non-ionic PAGs showed significantly better acid generation performance than the ionic onium salt PAGs tested. In particular, one non-ionic PAG showed almost an order of magnitude improvement in the Dill C acid generation rate constant as compared to a triarylsulfonium PAG. The high energy acid generation efficiency was found to correlate well with the electron affinity of the PAGs, suggesting that improvements in PAG design can be predicted. Non-ionic PAGs merit further investigation as a means for producing higher sensitivity resists under high energy exposure sources.

  2. water-soluble fluorocarbon coating

    NASA Technical Reports Server (NTRS)

    Nanelli, P.


    Water-soluble fluorocarbon proves durable nonpolluting coating for variety of substrates. Coatings can be used on metals, masonry, textiles, paper, and glass, and have superior hardness and flexibility, strong resistance to chemicals fire, and weather.

  3. Water-soluble l-cysteine-coated FePt nanoparticles as dual MRI/CT imaging contrast agent for glioma

    PubMed Central

    Liang, Shuyan; Zhou, Qing; Wang, Min; Zhu, Yanhong; Wu, Qingzhi; Yang, Xiangliang


    Nanoparticles (NPs) are advantageous for the delivery of diagnosis agents to brain tumors. In this study, we attempted to develop an l-cysteine coated FePt (FePt-Cys) NP as MRI/CT imaging contrast agent for the diagnosis of malignant gliomas. FePt-Cys NPs were synthesized through a co-reduction route, which was characterized by transmission electron microscopy, high-resolution transmission electron microscopy, powder X-ray diffraction, Fourier transform infrared spectroscopy, and dynamic light scattering. The MRI and CT imaging ability of FePt-Cys NPs was evaluated using different gliomas cells (C6, SGH44, U251) as the model. Furthermore, the biocompatibility of the as-synthesized FePt-Cys NPs was evaluated using three different cell lines (ECV304, L929, and HEK293) as the model. The results showed that FePt-Cys NPs displayed excellent biocompatibility and good MRI/CT imaging ability, thereby indicating promising potential as a dual MRI/CT contrast agent for the diagnosis of brain malignant gliomas. PMID:25848253

  4. Oxidative potential of ambient water-soluble PM2.5 in the southeastern United States: contrasts in sources and health associations between ascorbic acid (AA) and dithiothreitol (DTT) assays

    NASA Astrophysics Data System (ADS)

    Fang, Ting; Verma, Vishal; Bates, Josephine T.; Abrams, Joseph; Klein, Mitchel; Strickland, Matthew J.; Sarnat, Stefanie E.; Chang, Howard H.; Mulholland, James A.; Tolbert, Paige E.; Russell, Armistead G.; Weber, Rodney J.


    The ability of certain components of particulate matter to induce oxidative stress through the generation of reactive oxygen species (ROS) in vivo may be one mechanism accounting for observed linkages between ambient aerosols and adverse health outcomes. A variety of assays have been used to measure this so-called aerosol oxidative potential. We developed a semi-automated system to quantify oxidative potential of filter aqueous extracts utilizing the dithiothreitol (DTT) assay and report here the development of a similar semi-automated system for the ascorbic acid (AA) assay. Approximately 500 PM2.5 filter samples collected in contrasting locations in the southeastern US were analyzed for a host of aerosol species, along with AA and DTT activities. We present a detailed contrast in findings from these two assays. Water-soluble AA activity was higher in summer and fall than in winter, with highest levels near heavily trafficked highways, whereas DTT activity was higher in winter compared to summer and fall and more spatially homogeneous. AA activity was nearly exclusively correlated with water-soluble Cu (r = 0.70-0.94 at most sites), whereas DTT activity was correlated with organic and metal species. Source apportionment models, positive matrix factorization (PMF) and a chemical mass balance method with ensemble-averaged source impact profiles (CMB-E), suggest a strong contribution from traffic emissions and secondary processes (e.g., organic aerosol oxidation or metals mobilization by secondary acids) to both AA and DTT activities in urban Atlanta. In contrast, biomass burning was a large source for DTT activity, but insignificant for AA. AA activity was not correlated with PM2.5 mass, while DTT activity co-varied strongly with mass (r = 0.49-0.86 across sites and seasons). Various linear models were developed to estimate AA and DTT activities for the central Atlanta Jefferson Street site, based on the CMB-E sources. The models were then used to estimate daily

  5. Ultrafiltration modeling of non-ionic microgels.


    Roa, Rafael; Zholkovskiy, Emiliy K; Nägele, Gerhard


    Membrane ultrafiltration (UF) is a pressure driven process allowing for the separation and enrichment of protein solutions and dispersions of nanosized microgel particles. The permeate flux and the near-membrane concentration-polarization (CP) layer in this process is determined by advective-diffusive dispersion transport and the interplay of applied and osmotic transmembrane pressure contributions. The UF performance is thus strongly dependent on the membrane properties, the hydrodynamic structure of the Brownian particles, their direct and hydrodynamic interactions, and the boundary conditions. We present a macroscopic description of cross-flow UF of non-ionic microgels modeled as solvent-permeable spheres. Our filtration model involves recently derived semi-analytic expressions for the concentration-dependent collective diffusion coefficient and viscosity of permeable particle dispersions [Riest et al., Soft Matter, 2015, 11, 2821]. These expressions have been well tested against computer simulation and experimental results. We analyze the CP layer properties and the permeate flux at different operating conditions and discuss various filtration process efficiency and cost indicators. Our results show that the proper specification of the concentration-dependent transport coefficients is important for reliable filtration process predictions. We also show that the solvent permeability of microgels is an essential ingredient to the UF modeling. The particle permeability lowers the particle concentration at the membrane surface, thus increasing the permeate flux. PMID:25921331

  6. Water-soluble polymers and compositions thereof


    Smith, Barbara F.; Robison, Thomas W.; Gohdes, Joel W.


    Water-soluble polymers including functionalization from the group of amino groups, carboxylic acid groups, phosphonic acid groups, phosphonic ester groups, acylpyrazolone groups, hydroxamic acid groups, aza crown ether groups, oxy crown ethers groups, guanidinium groups, amide groups, ester groups, aminodicarboxylic groups, permethylated polvinylpyridine groups, permethylated amine groups, mercaptosuccinic acid groups, alkyl thiol groups, and N-alkylthiourea groups are disclosed.

  7. Water-soluble polymers and compositions thereof


    Smith, B.F.; Robison, T.W.; Gohdes, J.W.


    Water-soluble polymers including functionalization from the group of amino groups, carboxylic acid groups, phosphonic acid groups, phosphonic ester groups, acylpyrazolone groups, hydroxamic acid groups, aza crown ether groups, oxy crown ethers groups, guanidinium groups, amide groups, ester groups, aminodicarboxylic groups, permethylated polyvinylpyridine groups, permethylated amine groups, mercaptosuccinic acid groups, alkyl thiol groups, and N-alkylthiourea groups are disclosed.

  8. Water-soluble polymers and compositions thereof


    Smith, Barbara F.; Robison, Thomas W.; Gohdes, Joel W.


    Water-soluble polymers including functionalization from the group of amino groups, carboxylic acid groups, phosphonic acid groups, phosphonic ester groups, acylpyrazolone groups, hydroxamic acid groups, aza crown ether groups, oxy crown ethers groups, guanidinium groups, amide groups, ester groups, aminodicarboxylic groups, permethylated polyvinylpyridine groups, permethylated amine groups, mercaptosuccinic acid groups, alkyl thiol groups, and N-alkylthiourea groups are disclosed.

  9. Biochemical synthesis of water soluble conducting polymers

    NASA Astrophysics Data System (ADS)

    Bruno, Ferdinando F.; Bernabei, Manuele


    An efficient biomimetic route for the synthesis of conducting polymers/copolymers complexed with lignin sulfonate and sodium (polystyrenesulfonate) (SPS) will be presented. This polyelectrolyte assisted PEG-hematin or horseradish peroxidase catalyzed polymerization of pyrrole (PYR), 3,4 ethyldioxithiophene (EDOT) and aniline has provided a route to synthesize water-soluble conducting polymers/copolymers under acidic conditions. The UV-vis, FTIR, conductivity and cyclic voltammetry studies for the polymers/copolymer complex indicated the presence of a thermally stable and electroactive polymers. Moreover, the use of water-soluble templates, used as well as dopants, provided a unique combination of properties such as high electronic conductivity, and processability. These polymers/copolymers are nowadays tested/evaluated for antirust features on airplanes and helicopters. However, other electronic applications, such as photovoltaics, for transparent conductive polyaniline, actuators, for polypyrrole, and antistatic films, for polyEDOT, will be proposed.

  10. Water-soluble titanium alkoxide material


    Boyle, Timothy J.


    A water soluble, water stable, titanium alkoxide composition represented by the chemical formula (OC.sub.6H.sub.6N).sub.2Ti(OC.sub.6H.sub.2(CH.sub.2N(CH.sub.3).sub.2).sub- .3-2,4,6).sub.2 with a theoretical molecular weight of 792.8 and an elemental composition of 63.6% C, 8.1% H, 14.1% N, 8.1% O and 6.0% Ti.

  11. Water-soluble derivatives of 1 -tetrahydrocannabinol.


    Zitko, B A; Howes, J F; Razdan, R K; Dalzell, B C; Dalzell, H C; Sheehan, J C; Pars, H G; Dewey, W L; Harris, L S


    Delta1-Tetrahydrocannabinol, which is resinous and insoluble in water and therefore difficult to study pharmacologically, can be converted to a watersoluble derivative without loss of its biological activity. This has been achieved by preparing esters bearing a nitrogen moiety with the use of carbodiimide as the condensing agent. The availability of such water-soluble derivatives will allow the evaluation of Delta1-tetrahydrocannabinol in self-administration studies in monkeys for its addiction liability potential in man. This technique of water solubilization is also applicable to other compounds of chemical and biological significance. PMID:5043146

  12. A Water-Soluble Polythiophene for Organic Field-Effect Transistors

    SciTech Connect

    Shao, Ming; He, Youjun; Hong, Kunlun; Rouleau, Christopher M; Geohegan, David B; Xiao, Kai


    Synthesis of a non-ionic, water-soluble poly(thiophene) (PT) derivative, poly(3-(2-(2-methoxyethoxy) ethoxy)ethoxy) methylthiophene) (P3TEGT) with a hydrophilic tri-ethylene glycol side group, is reported and thin films of the polymer suitable for organic field-effect transistors (OFETs) are characterized by combining analysis techniques that include UV-Vis absorption and fluorescence spectroscopy, x-ray diffraction, and atomic force microscopy. After thermal annealing, P3TEGT films exhibit a well-organized nanofibrillar lamellar nanostructure that originates from the strong - stacking of the thiophene backbones. P-type organic field-effect transistors (OFETs) with hole mobilities of 10-5 cm2V-1s-1 were fabricated from this water-soluble poly(thiophene) derivative, demonstrating the possibility that environmentally-friendly solvents may be promising alternatives for the low-cost, green solution-based organic electronic device manufacturing of OFETs, organic photovoltaics (OPVs), and biosensors.

  13. Water solubility in pyrope at high pressures

    NASA Astrophysics Data System (ADS)

    Mookherjee, M.; Karato, S.-


    To address how much water is stored within the Earth's mantle, we need to understand the water solubility in the nominally anhydrous minerals. Much is known about olivine and pyroxene. Garnet is another important component, approaching 40% by volume in the transition zone. Only two studies on water solubility in pyrope at high-pressures exist which contradict each other. Lu and Keppler (1997) observed increase in water solubility in a natural pyrope up to 200 ppm wt of water, till 10 GPa. They concluded that the proton is located in the interstitial site. Withers et al. (1998) on the contrary, observed increasing water content in Mg-rich pyrope till 6 GPa, then sudden decrease of water, beyond detection, at 7 GPa. Based on infrared spectra, Withers et al. (1998), concluded hydrogarnet (Si^{4+} replaced by 4H+ to form O4H4) substitution in synthetic magnesium rich pyrope. They argued that at high pressure owing to larger volume, hydrogarnet substitution is unstable and water is expelled out of garnet. In transition zone conditions, however, majorite garnet seems to contain around 600-700 ppm wt of water (Bolfan-Casanova et al. 2000; Katayama et al. 2003). The cause for such discrepancy is not clear and whether garnet could store a significant amount of water at mantle condition is unconstrained. In order to understand the solubility mechanism of water in pyrope at high-pressure, we have conducted high- pressure experiments on naturally occurring single crystals of pyrope garnet (from Arizona, Aines and Rossman, 1984). To ascertain water-saturated conditions, we use olivine single-crystal as an internal standard. Preliminary results indicate that natural pyrope is capable of dissolving water at high-pressures, however, water preferentially enters olivine than in pyrope. We are undertaking systematic study to estimate the solubility of water in pyrope as a function of pressure. This will enable us to develop solubility models to understand the defect mechanisms

  14. Water soluble complexes of carotenoids with arabinogalactan.


    Polyakov, Nikolay E; Leshina, Tatyana V; Meteleva, Elizaveta S; Dushkin, Alexander V; Konovalova, Tatyana A; Kispert, Lowell D


    We present the first example of water soluble complexes of carotenoids. The stability and reactivity of carotenoids in the complexes with natural polysaccharide arabinogalactan were investigated by different physicochemical techniques: optical absorption, HPLC, and pulsed EPR spectroscopy. Compared to pure carotenoids, polysaccharide complexes of carotenoids showed enhanced photostability by a factor of 10 in water solutions. A significant decrease by a factor of 20 in the reactivity toward metal ions (Fe(3+)) and reactive oxygen species in solution was detected. On the other hand, the yield and stability of carotenoid radical cations photoproduced on titanium dioxide (TiO(2)) were greatly increased. EPR measurements demonstrated efficient charge separation on complex-modified TiO(2) nanoparticles (7 nm). Canthaxanthin radical cations are stable for approximately 10 days at room temperature in this system. The results are important for a variety of carotenoid applications, in the design of artificial light-harvesting, photoredox, and catalytic devices. PMID:19061372

  15. A water-soluble gadolinium metallofullerenol: facile preparation, magnetic properties and magnetic resonance imaging application.


    Li, Jie; Wang, Taishan; Feng, Yongqiang; Zhang, Ying; Zhen, Mingming; Shu, Chunying; Jiang, Li; Wang, Yuqing; Wang, Chunru


    A new water-soluble gadolinium metallofullerenol was prepared through a solid-liquid reaction. It was characterized to have an enhanced effective magnetic moment, and improved T1-weighted relaxivity and magnetic resonance imaging performance in the liver. This material prepared by a facile method has wide application as a contrast agent and biological medicine. PMID:27064096

  16. Teratogenicity and metabolism of water-soluble forms of vitamin A in the pregnant rat

    SciTech Connect

    Gunning, D.B.; Barua, A.B.; Olson, J.A. )


    Retinoyl {beta}-glucuronide, unlike retinoic acid, has been shown to be non-teratogenic when administered orally, even in large doses, to pregnant rats. The degree to which water-solubility is associated with low teratogenicity is not known. Other water-soluble forms of vitamin A have now been synthesized in our laboratory and are being evaluated for teratogenicity. New water-soluble forms of vitamin A were administered orally to pregnant Sprague-Dawley rats in a single dose of 0.35 mmole/kg bw on day 8 of gestation. On day 19, the dams were sacrificed and the litters were examined. Control animals received either vehicle only or an equivalent dose of all-trans retinoic acid. Maternal and fetal tissues were taken and analyzed by HPLC for vitamin A metabolites. In another experiment, a large single oral dose of the radiolabelled water-soluble compound was administered on day 10. At either 30 minutes or 1 hour after the dose, dams were sacrificed and the embryos analyzed both for radioactivity and for specific metabolites. In contrast to retinoyl {beta}-glucuronide, retinoyl {beta}-glucose is highly teratogenic under identical conditions. Thus, water-solubility does not seem to be the determining factor in the teratogenicity of retinoic acid conjugates.

  17. Ice nucleation by water-soluble macromolecules

    NASA Astrophysics Data System (ADS)

    Pummer, B. G.; Budke, C.; Augustin-Bauditz, S.; Niedermeier, D.; Felgitsch, L.; Kampf, C. J.; Huber, R. G.; Liedl, K. R.; Loerting, T.; Moschen, T.; Schauperl, M.; Tollinger, M.; Morris, C. E.; Wex, H.; Grothe, H.; Pöschl, U.; Koop, T.; Fröhlich-Nowoisky, J.


    Cloud glaciation is critically important for the global radiation budget (albedo) and for initiation of precipitation. But the freezing of pure water droplets requires cooling to temperatures as low as 235 K. Freezing at higher temperatures requires the presence of an ice nucleator, which serves as a template for arranging water molecules in an ice-like manner. It is often assumed that these ice nucleators have to be insoluble particles. We point out that also free macromolecules which are dissolved in water can efficiently induce ice nucleation: the size of such ice nucleating macromolecules (INMs) is in the range of nanometers, corresponding to the size of the critical ice embryo. As the latter is temperature-dependent, we see a correlation between the size of INMs and the ice nucleation temperature as predicted by classical nucleation theory. Different types of INMs have been found in a wide range of biological species and comprise a variety of chemical structures including proteins, saccharides, and lipids. Our investigation of the fungal species Acremonium implicatum, Isaria farinosa, and Mortierella alpina shows that their ice nucleation activity is caused by proteinaceous water-soluble INMs. We combine these new results and literature data on INMs from fungi, bacteria, and pollen with theoretical calculations to develop a chemical interpretation of ice nucleation and water-soluble INMs. This has atmospheric implications since many of these INMs can be released by fragmentation of the carrier cell and subsequently may be distributed independently. Up to now, this process has not been accounted for in atmospheric models.

  18. A water-soluble luminescence oxygen sensor.


    Castellano, F N; Lakowicz, J R


    We developed a water-soluble luminescent probe for dissolved oxygen. This probe is based on (Ru[dpp(SO3Na)2]3) cl2, which is a sulfonated analogue of the well-known oxygen probe (Ru[dpp]3)cl2. The compound dpp is 4,7-diphenyl-1,10-phenanthroline and dpp(SO3Na)2 is a disulfonated derivative of the same ligand. In aqueous solution in the absence of oxygen (Ru[dpp(SO3Na)2]3)cl2 displays a lifetime of 3.7 microseconds that decreases to 930 ns on equilibrium with air and 227 ns on equilibrium with 100% oxygen. The Stern-Volmer quenching constant is 11,330 M-1. This high oxygen-quenching constant means that the photoluminescence of Ru(dpp[SO3Na]2)3cl2 is 10% quenched at an oxygen concentration of 8.8 x 10(-6) M, or equilibration with 5.4 torr of oxygen. The oxygen probe dissolved in water displays minimal interactions with lipid vesicles composed of dipalmityl-L-alpha-phosphatidyl glycerol but does appear to interact with human serum albumin. The absorption maximum near 480 nm, long lifetime and large Stokes' shift allow this probe to be used with simple instrumentation based on a light-emitting diode light source, allowing low-cost oxygen sensing in aqueous solutions. To the best of our knowledge this is the first practical water-soluble oxygen sensor. PMID:9487796

  19. Water-soluble dietary fibers and cardiovascular disease.


    Theuwissen, Elke; Mensink, Ronald P


    One well-established way to reduce the risk of developing cardiovascular disease (CVD) is to lower serum LDL cholesterol levels by reducing saturated fat intake. However, the importance of other dietary approaches, such as increasing the intake of water-soluble dietary fibers is increasingly recognized. Well-controlled intervention studies have now shown that four major water-soluble fiber types-beta-glucan, psyllium, pectin and guar gum-effectively lower serum LDL cholesterol concentrations, without affecting HDL cholesterol or triacylglycerol concentrations. It is estimated that for each additional gram of water-soluble fiber in the diet serum total and LDL cholesterol concentrations decrease by -0.028 mmol/L and -0.029 mmol/L, respectively. Despite large differences in molecular structure, no major differences existed between the different types of water-soluble fiber, suggesting a common underlying mechanism. In this respect, it is most likely that water-soluble fibers lower the (re)absorption of in particular bile acids. As a result hepatic conversion of cholesterol into bile acids increases, which will ultimately lead to increased LDL uptake by the liver. Additionally, epidemiological studies suggest that a diet high in water-soluble fiber is inversely associated with the risk of CVD. These findings underlie current dietary recommendations to increase water-soluble fiber intake. PMID:18302966

  20. New water soluble pyrroloquinoline derivatives as new potential anticancer agents.


    Ferlin, Maria Grazia; Marzano, Christine; Dalla Via, Lisa; Chilin, Adriana; Zagotto, Giuseppe; Guiotto, Adriano; Moro, Stefano


    A new class of water soluble 3H-pyrrolo[3,2-f]quinoline derivatives has been synthesized and investigated as potential anticancer drugs. Water solubility profiles have been used to select the most promising derivatives. The novel compound 10, having two (2-diethylamino-ethyl) side chains linked through positions 3N and 9O, presents a suitable water solubility profile, and it was shown to exhibit cell growth inhibitory properties when tested against the in-house panel of cell lines, in particular those obtained from melanoma. PMID:15936202

  1. Polyglycerol-Dendronized Perylenediimides as Stable, Water-Soluble Fluorophores

    PubMed Central

    Yang, Si Kyung


    The synthesis and photophysical properties of water-soluble, fluorescent polyglycerol-dendronized perylenediimides 1–4 are reported. The polyglycerol dendrons, which are known to be highly biocompatible, are found to confer high water-solubility on the perylenediimide in aqueous media while retaining its excellent fluorescent properties. Furthermore, intramolecular cross-linking of the polyglycerol dendrons using the ring-closing metathesis reaction not only enhances the photostability but also reduces the size of perylenediimide-cored dendrimers. The permeability of the various dendritic shells is probed using heavy metal ion quenchers and compared to non-dendritic but water-soluble perylenediimide 5. PMID:23459294

  2. Which Starch Fraction is Water-Soluble, Amylose or Amylopectin?

    ERIC Educational Resources Information Center

    Green, Mark M.; And Others


    A survey of 22 popular organic chemistry textbooks showed that only four correctly stated that of the two components of starch, amylopectin is the water-soluble, and amylose is the water-insoluble. (MLH)

  3. Water-soluble rhamnose-coated Fe3O4 nanoparticles.


    Lartigue, Lenaic; Oumzil, Khalid; Guari, Yannick; Larionova, Joulia; Guérin, Christian; Montero, Jean-Louis; Barragan-Montero, Veronique; Sangregorio, Claudio; Caneschi, Andrea; Innocenti, Claudia; Kalaivani, T; Arosio, P; Lascialfari, A


    Water-soluble biocompatible rhamnose-coated Fe(3)O(4) nanoparticles of 4.0 nm are obtained by covalent anchorage of rhamnose on the nanoparticles surface via a phosphate linker. These nanoparticles present superparamagnetic behavior and nuclear relaxivities in the same order of magnitude as Endorem that make them potential magnetic resonance imaging (MRI) contrast agents of a second generation, where the saccharides represent also specific ligands able to target lectins on skin cells. PMID:19545163

  4. Screening of non-Ionic Surfactant for Enhancing Biobutanol Production.


    Dhamole, Pradip B; Mane, Ravindra G; Feng, Hao


    This work deals with finding a suitable non-ionic surfactant which has high butanol capturing capacity and can be separated at a temperature close to room temperature and does not extract any intermediates or substrate (i.e., glucose). Importantly, it should be biocompatible, and its separation from the aqueous phase is not affected by other fermentation products. Hence, a pool of non-ionic Pluronic surfactants (L31, L61, L62D, L62LF, L62, L81, L92, L101, L121, L64, P65, P84, P104, P105) were selected for the study. Screening of the surfactant was done based on its hydrophile-lipophile balance (HLB) value, butanol capturing capacity (BCC), and cloud point temperature. Among the various surfactant investigated, L62D captured maximum amount of butanol (0.68 g/g of surfactant). Also, the cloud point temperature of L62D is close to room temperature (28.7 °C). Biocompatibility studies were carried out by conducting fermentation in presence of 3% L62D which resulted in 148% increase in butanol production as compared to control (without surfactant). Further, the fermentation products did not have strong influence on phase separation. PMID:26315133

  5. Self-microemulsifying smaller molecular volume oil (Capmul MCM) using non-ionic surfactants: a delivery system for poorly water-soluble drug.


    Bandivadeka, Mithun Mohanraor; Pancholi, Shyam Sundar; Kaul-Ghanekar, Ruchika; Choudhari, Amit; Koppikar, Soumya


    The main purpose of this work is to formulate self-microemulsifying drug delivery system (SMEDDS) using smaller molecular oil with Atorvastatin calcium as a model drug. Solubility of the selected drug was accessed in oils and surfactants. Percent transmittance (%T) test study was performed to identify the efficient self-microemulsifying formulations. Those formulations which showed higher value for %T were evaluated for droplet size, polydispersity index, ζ potential, refractive index and cloud point measurement. Effect of drug loading on droplet size, increasing dilution in different media, thermodynamic stability and in vitro dissolution was performed to observe the performance of the selected formulation. Further cytotoxicity and permeation enhancement studies were carried out on Caco2 cell lines. Of all the oils accessed for drug solubility, Capmul MCM showed higher solubility capacity for Atorvastatin calcium. Capmul MCM was better microemulsified using combination of Tween 20 and Labrasol surfactant. Droplet size was as low as 86.93 nm with polydispersity index and ζ potential at 0.195 ± 0.011 and -7.27 ± 3.11 mV respectively. The selected undiluted formulation showed refractive index values ranging from 1.40 to 1.47 indicating the isotropicity of the formulation. The selected formulation was robust to dilution in different media and thermodynamically stable. Dissolution profile was enhanced for the selected drug as compared to marketed formulation with t85% and DE values at 10 min and 80.15 respectively. Also cytotoxicity measurement showed minimum effect with good permeation enhancing capacity. Thus our study demonstrates the use of smaller molecular oil (Capmul MCM) for developing self-microemulsifying drug delivery system for better in vitro and in vivo performance. PMID:22087760

  6. Non-ionic surfactant phase diagram prediction by recursive partitioning.


    Bell, Gordon


    A model has been designed to predict the phase which forms in water for a non-ionic surfactant, at a given concentration and temperature. The full phase diagram is generated by selecting enough data points to cover the region of interest. The model estimates the probability for each one of 10 possible phases and selects the one with the highest likelihood. The probabilities are based on the recursive partitioning of a dataset of 10 000 known observations. The model covers alkyl chain length and branching, ethoxylate head length and number, and end capping of one or more of the ethoxylate chains. The relationship between chemical structure, shape and phase behaviour is discussed.This article is part of the themed issue 'Soft interfacial materials: from fundamentals to formulation'. PMID:27298439

  7. Potentiometric analysis of water soluble cutting fluid-metal combinations

    SciTech Connect

    Kelley, E.E.


    The results of corrosion studies conducted by the University of Kansas under Contract G257763 for Allied-Signal Inc., Kansas City Division (KCD), are given. These potentiometric studies evaluate the corrosivity of two water soluble cutting fluids at varying concentrations on samples of 304 stainless steel, 6061-T6 aluminum, and beryllium copper. This testing serves two purposes: (1) to develop effective test procedures adaptable to existing KCD corrosion measurement equipment for corrosion analysis of cutting fluid-metals combinations, and (2) to understand the relative corrosiveness of the varying water soluble cutting fluids on different metals. The tests used were adapted from the American Society of Testing Materials (ASTM). Future testing will identify polarization techniques for establishing corrosion rates which will be used in evaluating both water soluble cutting fluids and other aqueous solutions used at KCD.

  8. Water-soluble iridium phosphorescent complexes for OLED applications

    NASA Astrophysics Data System (ADS)

    Eum, Min-Sik; Yoon, Heekoo; Kim, Tae Hyung


    Newly prepared water-soluble iridium phosphorescent complexes, trans-[Ir(ppy)(PAr3)2(H)L]0,+ (ppy = bidentate 2-phenylpyridinato anionic ligand; L= Cl (1), CO (2), CN- (3); H being trans to the nitrogen of ppy ligand; PAr3 (TPPTS) = P(m-C6H4SO3Na)3), have been synthesized and characterized. Those complexes containing water-soluble phosphine ligands can emit any color region as altering cyclometalated ligands in aqueous media with high quantum efficiencies. Even though these water-soluble phosphorescent iridium complexes can be the sensing probe for toxic CO gas and CN anion, they will be capable of promising materials in the solution processible OLED applications.

  9. Water soluble cations and the fluvial history of Mars

    NASA Technical Reports Server (NTRS)

    Silverman, M. P.; Munoz, E. F.


    The electrical conductivity and water soluble Na, K, Ca, and Mg of aqueous solutions of terrestrial soils and finely divided igneous and metamorphic rocks were determined. Soils from dry terrestrial basins with a history of water accumulation as well as soils from the topographic lows of valleys accumulated water soluble cations, particularly Na and Ca. These soils as a group can be distinguished from the rocks or a second group of soils (leached upland soils and soils from sites other than the topographic lows of valleys) by significant differences in their mean electrical conductivity and water-soluble Na + Ca content. Similar measurements on multiple samples from the surface of Mars, collected by an automated long-range roving vehicle along a highlands-to-basin transect at sites with morphological features resembling dry riverlike channels, are suggested to determine the fluvial history of the planet.

  10. Preparation of microspheres of water-soluble pharmaceuticals.


    Huang, H P; Ghebre-Sellassie, I


    An emulsion-solvent evaporation procedure involving the dispersion of an alcoholic solution of an active in liquid paraffin was used to prepare microspheres of water-soluble pharmaceuticals using ethylcellulose as a carrier. The effects of surfactant, plasticizer, drug loading, and agitation speed on drug release rate from the microspheres were evaluated. The release rates of water-soluble drugs from microspheres, ranging from 100 and 500 microns in diameter, were sustained over an extended time and were found to be related to the ratio of drug to polymer in the final product. PMID:2723966

  11. New polymer improves water-soluble completion fluids

    SciTech Connect

    Mondshine, T.C. )


    Water-soluble suspended salt completion fluids were first introduced in early 1977. Since then, the system has been used worldwide for various applications including gravel packing, under reaming, perforating, controlling loss of brines, washing sands, workovers, horizontal drilling, and special coring operations. More recently, a newly developed polymer simplifies and improves the design of water-soluble completion fluids. This new polymer described in this paper, is synergistic with xanthan gum, contributes to suspension of salt particles, and controls filtration at temperatures up to 300 F without the need for calcium lignosulfonate.

  12. Leaching behavior of water-soluble carbohydrates from almond hulls

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over 58% of the dry matter content of the hulls from the commercial almond (Prunus dulcis (Miller) D.A. Webb) is soluble in warm water (50-70°C) extraction. The water-soluble extractables include useful amounts of fermentable sugars (glucose, fructose, sucrose), sugar alcohols (inositol and sorbito...

  13. Spectroscopic and Photochemical Properties of Water-Soluble Fullerenol

    EPA Science Inventory

    Fullerenol, a hydroxylated form of C60-fullerene, is of potential environmental and biological significance due to its buckyball structure, hydroxyl groups and high water solubility. Although fullerenol is known to be an efficient triplet photosensitizer, little is known about it...

  14. Preserving water soluble carbohydrate in hay and silage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The water soluble carbohydrate (WSC) content of forage may be manipulated by harvest timing within a 24-hour period to take advantage of the diurnal cycle. However, increases in carbohydrate may be lost during the haymaking or ensiling process. Rapid drying and dry storage is necessary to prevent lo...

  15. Transformation of acidic poorly water soluble drugs into ionic liquids.


    Balk, Anja; Wiest, Johannes; Widmer, Toni; Galli, Bruno; Holzgrabe, Ulrike; Meinel, Lorenz


    Poor water solubility of active pharmaceutical ingredients (API) is a major challenge in drug development impairing bioavailability and therapeutic benefit. This study is addressing the possibility to tailor pharmaceutical and physical properties of APIs by transforming these into tetrabutylphosphonium (TBP) salts, including the generation of ionic liquids (IL). Therefore, poorly water soluble acidic APIs (Diclofenac, Ibuprofen, Ketoprofen, Naproxen, Sulfadiazine, Sulfamethoxazole, and Tolbutamide) were converted into TBP ILs or low melting salts and compared to the corresponding sodium salts. Free acids and TBP salts were characterized by NMR and IR spectroscopy, DSC and XRPD, DVS and dissolution rate measurements, release profiles, and saturation concentration measurements. TBP salts had lower melting points and glass transition temperatures and dissolution rates were improved up to a factor of 1000 as compared to the corresponding free acid. An increase in dissolution rates was at the expense of increased hygroscopicity. In conclusion, the creation of TBP ionic liquids or solid salts from APIs is a valuable concept addressing dissolution and solubility challenges of poorly water soluble acidic compounds. The data suggested that tailor-made counterions may substantially expand the formulation scientist's armamentarium to meet challenges of poorly water soluble drugs. PMID:25976317

  16. Highly active water-soluble olefin metathesis catalyst.


    Hong, Soon Hyeok; Grubbs, Robert H


    A novel water-soluble ruthenium olefin metathesis catalyst supported by a poly(ethylene glycol) conjugated saturated 1,3-dimesityl-4,5-dihydroimidazol-2-ylidene ligand is reported. The catalyst displays improved activity in ring-opening metathesis polymerization, ring-closing metathesis, and cross-metathesis reactions in aqueous media. PMID:16536510

  17. Some physicochemical aspects of water-soluble mineral flotation.


    Wu, Zhijian; Wang, Xuming; Liu, Haining; Zhang, Huifang; Miller, Jan D


    Some physicochemical aspects of water-soluble mineral flotation including hydration phenomena, associations and interactions between collectors, air bubbles, and water-soluble mineral particles are presented. Flotation carried out in saturated salt solutions, and a wide range of collector concentrations for effective flotation of different salts are two basic aspects of water-soluble mineral flotation. Hydration of salt ions, mineral particle surfaces, collector molecules or ions, and collector aggregates play an important role in water-soluble mineral flotation. The adsorption of collectors onto bubble surfaces is suggested to be the precondition for the association of mineral particles with bubbles. The association of collectors with water-soluble minerals is a complicated process, which may include the adsorption of collector molecules or ions onto such surfaces, and/or the attachment of collector precipitates or crystals onto the mineral surfaces. The interactions between the collectors and the minerals include electrostatic and hydrophobic interactions, hydrogen bonding, and specific interactions, with electrostatic and hydrophobic interactions being the common mechanisms. For the association of ionic collectors with minerals with an opposite charge, electrostatic and hydrophobic interactions could have a synergistic effect, with the hydrophobic interactions between the hydrophobic groups of the previously associated collectors and the hydrophobic groups of oncoming collectors being an important attractive force. Association between solid particles and air bubbles is the key to froth flotation, which is affected by hydrophobicity of the mineral particle surfaces, surface charges of mineral particles and bubbles, mineral particle size and shape, temperature, bubble size, etc. The use of a collector together with a frother and the use of mixed surfactants as collectors are suggested to improve flotation. PMID:27346329

  18. Antinociceptive activity of Delta9-tetrahydrocannabinol non-ionic microemulsions.


    Lazzari, P; Fadda, P; Marchese, G; Casu, G L; Pani, L


    Delta(9)-Tetrahydrocannabinol (Delta(9)-THC), the major psychoactive constituent of Cannabis sativa L., has been widely studied for its potential pharmaceutical application in the treatment of various diseases and disturbs. This sparingly soluble terpeno-phenolic compound is not easy to handle and to be formulated in pharmaceutical preparations. The aim of this work was to develop a stable aqueous Delta(9)-THC formulation acceptable for different ways of administration, and to evaluate the therapeutic properties of the new Delta(9)-THC based preparation for pain treatment. Due to the thermodynamic stability and advantages of microemulsion based systems, the study was focused on the identification of aqueous microemulsion based systems containing Delta(9)-THC. Oil in water Delta(9)-THC microemulsions were individuated through phase diagrams construction, using the non-ionic surfactant Solutol HS15, being this surfactant acceptable for parenteral administration in human. A selected microemulsion samples containing 0.2 wt% of Delta(9)-THC, stable up to 52 degrees C, was successfully assayed on animal models of pain. Significant antinociceptive activity has been detected by both intraperitoneal and intragastric administration of the new Delta(9)-THC pharmaceutical preparation. The effect has been highlighted in shorter time if compared to a preparation of the same active principle based on previously reported conventional preparation. PMID:20399844

  19. Activated sludge acclimatisation kinetics to non-ionic surfactants.


    Carvalho, G; Novais, J M; Pinheiro, H M


    The biodegradation of surfactants is a frequent and complex problem in domestic and industrial wastewater treatment processes. In addition to the resulting metabolites being sometimes refractory, the complete biodegradation of many of the most employed non-ionic surfactants requires long hydraulic retention times and the presence of specialised bacterial consortia. Preliminary acclimatisation tests highlighted the importance of the sludge acclimatisation state to a specific surfactant substrate for biotreatment efficiency. This paper reports on studies aimed at quantifying activated sludge acclimatisation and memory retention levels when subjected to changes in the type of surfactant included in the feed. Several transitions were tested, namely from an alkylphenol ethoxylate to a linear alkyl ethoxylate and the reverse, and between alkyl ethoxylates with different hydrophobic and hydrophilic molecular chain lengths. The kinetic results showed that sludge activation and memory loss were more dynamic for primary biodegradation It was found that the sludge was harder to adapt to alkylphenol ethoxylate than to alkyl ethoxylate. The former also apparently introduced an inhibitory effect, resulting in very slow degradation kinetics when imposed to alkyl ethoxylate acclimatised sludge. When replacing an alkyl ethoxylate with another surfactant of the same family, a longer ethoxylate chain reduced the degradation rates. This effect was further enhanced by simultaneously increasing the hydrophobic chain length of the substrate. The acclimatisation kinetic after the replacement of an alkyl ethoxylate by a longer counterpart was slower than the reverse case, and memory was also more easily lost. PMID:12641258

  20. Three bisphosphonate ligands improve the water solubility of quantum dots.


    Abdul Ghani, Siti Fatimah; Wright, Michael; Paramo, Juan Gallo; Bottrill, Melanie; Green, Mark; Long, Nicholas; Thanou, Maya


    Synthesised Quantum Dots (QDs) require surface modification in order to improve their aqueous dispersion and biocompatibility. Here, we suggest bisphosphonate molecules as agents to modify the surface of QDs for improved water solubility and biocompatibility. QDs_TOPO (CdSe/ZnS-trioctylphosphine oxide) were synthesised following modification of the method of Bawendi et al. (J. Phys. Chem. B, 1997, 101, 9463-9475). QDs surface modification is performed using a ligand exchange reaction with structurally different bisphosphonates (BIPs). The BIPs used were ethylene diphosphonate (EDP), methylenediphosphonate (MDP) and imidodiphosphonate (IDP). After ligand exchange, the QDs were extensively purified using centrifugation, PD-10 desalting columns and mini dialysis filters. Transmission electron microscopy (TEM) and fluorescent spectroscopy have been used to characterise the size and optical properties of the QDs. Cell toxicity was investigated using MTT (tetrazolium salt) and glutathione assays and intracellular uptake was imaged using confocal laser scanning microscopy and assessed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). QDs_TOPO and QDs-capped with BIPs (QDs_BIPs) were successfully synthesised. TEM showed the size and morphology of the QDs to be 5-7 nm with spherical shape. The stabilised QDs_BIPs showed significantly improved dispersion in aqueous solutions compared to QDs_TOPO. The cytotoxicity studies showed very rapid cell death for cells treated by QDs_TOPO and a minor effect on cell viability when QDs_BIPs were applied to the cells. Both EDP- and MDP-modified QDs did not significantly increase the intracellular levels of glutathione. In contrast, IDP-modified QDs substantially increased the intracellular glutathione levels, indicating potential cadmium leakage and inability of IDP to adequately cap and stabilise the QDs. EDP- and MDP-modified QDs were taken up by IGROV-1 (ovarian cancer) cells as shown by fluorescence microscopy, however, the

  1. Antioxidant Properties of Water-Soluble Fullerene Derivatives

    NASA Astrophysics Data System (ADS)

    Beuerle, Florian; Lebovitz, Russell; Hirsch, Andreas

    Due to their inherent electronic properties, fullerenes are considered as radical sponges being capable of effectively quenching reactive oxygen species (ROS). The most promising candidates for potential pharmaceutical applications are therefore water-soluble fullerene derivatives, since they provide reasonable biological availability. In light of these considerations, we give an overview over the most recent concepts for designing and synthesizing real water-soluble fullerene compounds. Several studies concerning the quenching activities against ROS-like Superoxide radical anion of some of these novel compounds are reviewed. We finally present first promising investigations about cytoprotective and neuroprotective activities of several carboxyfullerenes in zebrafish embroys as a mammalian model system. By comparing the activities for different addition patterns and other structural changes some first conclusions concerning a structure-function relationship can be drawn.

  2. Minimalist design of water-soluble cross-[beta] architecture

    SciTech Connect

    Biancalana, Matthew; Makabe, Koki; Koide, Shohei


    Demonstrated successes of protein design and engineering suggest significant potential to produce diverse protein architectures and assemblies beyond those found in nature. Here, we describe a new class of synthetic protein architecture through the successful design and atomic structures of water-soluble cross-{beta} proteins. The cross-{beta} motif is formed from the lamination of successive {beta}-sheet layers, and it is abundantly observed in the core of insoluble amyloid fibrils associated with protein-misfolding diseases. Despite its prominence, cross-{beta} has been designed only in the context of insoluble aggregates of peptides or proteins. Cross-{beta}'s recalcitrance to protein engineering and conspicuous absence among the known atomic structures of natural proteins thus makes it a challenging target for design in a water-soluble form. Through comparative analysis of the cross-{beta} structures of fibril-forming peptides, we identified rows of hydrophobic residues ('ladders') running across {beta}-strands of each {beta}-sheet layer as a minimal component of the cross-{beta} motif. Grafting a single ladder of hydrophobic residues designed from the Alzheimer's amyloid-{beta} peptide onto a large {beta}-sheet protein formed a dimeric protein with a cross-{beta} architecture that remained water-soluble, as revealed by solution analysis and x-ray crystal structures. These results demonstrate that the cross-{beta} motif is a stable architecture in water-soluble polypeptides and can be readily designed. Our results provide a new route for accessing the cross-{beta} structure and expanding the scope of protein design.

  3. Compositional Analysis of Water-Soluble Materials in Corn Stover

    SciTech Connect

    Chen, S. F.; Mowery, R. A.; Scarlata, C. J.; Chambliss, C. K.


    Corn stover is one of the leading feedstock candidates for commodity-scale biomass-to-ethanol processing. The composition of water-soluble materials in corn stover has been determined with greater than 90% mass closure in four of five representative samples. The mass percentage of water-soluble materials in tested stover samples varied from 14 to 27% on a dry weight basis. Over 30 previously unknown constituents of aqueous extracts were identified and quantified using a variety of chromatographic techniques. Monomeric sugars (primarily glucose and fructose) were found to be the predominant water-soluble components of corn stover, accounting for 30-46% of the dry weight of extractives (4-12% of the dry weight of feedstocks). Additional constituents contributing to the mass balance for extractives included various alditols (3-7%), aliphatic acids (7-21%), inorganic ions (10-18%), oligomeric sugars (4-12%), and a distribution of oligomers tentatively identified as being derived from phenolic glycosides (10-18%).

  4. Possible sources of two size-resolved water-soluble organic carbon fractions at a roadway site during fall season

    NASA Astrophysics Data System (ADS)

    Park, Seung-Shik; Kim, Ja-Hyun


    To examine the formation pathways of two size-resolved water-soluble organic carbon (WSOC) fractions, a total of 16 sets of size-segregated aerosol samples were collected using a 10-stage Micro-Orifice Uniform Deposit Impactor (MOUDI) at a roadway site in Korea from September 29 to October 29, 2010. A XAD7HP (non-ionic aliphatic acrylic polymer) resin column was used to separate the filtered extracts into hydrophilic (WSOCHPI) and hydrophobic (WSOCHPO) WSOC fractions. Also the size distributions of water-soluble inorganic species and oxalate were examined to determine the formation pathways of size-resolved WSOCHPI and WSOCHPO fractions. The size distribution of WSOCHPI showed a dominant mode at 0.55 μm, while the WSOCHPO had dominant modes at both 0.17-0.32 μm and 0.55 μm. On the basis of the size distribution characteristics, it was found that the formation pathways of both WSOCHPI and WSOCHPO were dependent on the particle size; in the condensation mode (0.17-0.32 μm), both the WSOCHPI and WSOCHPO could be produced through atmospheric processes similar to those of SO42- and oxalate, which were derived from the gas-phase oxidations of organic compounds. In the droplet mode (0.55-1.8 μm), the cloud processing of both the organic compounds and biomass burning emissions could be a major pathway for the WSOCHPI formation. However, the droplet mode WSOCHPO was likely produced through cloud processing and heterogeneous reactions or aerosol-phase reactions. In the coarse mode (>3.1 μm), the WSOCHPI formation was more likely associated with soil-related particles (Ca(NO3)2 and CaSO4) than with sea-salt particles (NaNO3 and Na2SO4).

  5. Bioconjugatable Porphyrins Bearing a Compact Swallowtail Motif for Water Solubility

    PubMed Central

    Borbas, K. Eszter; Mroz, Pawel; Hamblin, Michael R.; Lindsey, Jonathan S.


    A broad range of applications requires access to water-soluble, bioconjugatable porphyrins. Branched alkyl groups attached at the branching site to the porphyrin meso position are known to impart high organic solubility. Such “swallowtail” motifs bearing a polar group (hydroxy, dihydroxyphosphoryl, dihydroxyphosphoryloxy) at the terminus of each branch have now been incorporated at a meso site in trans-AB-porphyrins. The incorporation of the swallowtail motif relies on rational synthetic methods whereby a 1,9-bis(N-propylimino)dipyrromethane (bearing a bioconjugatable tether at the 5-position) is condensed with a dipyrromethane (bearing a protected 1,5-dihydroxypent-3-yl unit at the 5-position). The two hydroxy groups in the swallowtail motif of each of the resulting zinc porphyrins can be transformed to the corresponding diphosphate or diphosphonate product. A 4-(carboxymethyloxy)phenyl group provides the bioconjugatable tether. The six such porphyrins reported here are highly water-soluble (≥20 mM at room temperature in water at pH 7) as determined by visual inspection, UV–vis absorption spectroscopy, or 1H NMR spectroscopy. Covalent attachment was carried out in aqueous solution with the unprotected porphyrin diphosphonate and a monoclonal antibody against the T-cell receptor CD3ε. The resulting conjugate performed comparably to a commercially available fluorescein isothiocyanate-labeled antibody with Jurkat cells in flow cytometry and fluorescence microscopy assays. Taken together, this work enables preparation of useful quantities of water-soluble, bioconjugatable porphyrins in a compact architecture for applications in the life sciences. PMID:16704201

  6. Dithiocarbamates as capping ligands for water-soluble quantum dots.


    Zhang, Yanjie; Schnoes, Allison M; Clapp, Aaron R


    We investigated the suitability of dithiocarbamate (DTC) species as capping ligands for colloidal CdSe-ZnS quantum dots (QDs). DTC ligands are generated by reacting carbon disulfide (CS(2)) with primary or secondary amines on appropriate precursor molecules. A biphasic exchange procedure efficiently replaces the existing hydrophobic capping ligands on the QD surface with the newly formed DTCs. The reaction conversion is conveniently monitored by UV-vis absorption spectroscopy. Due to their inherent water solubility and variety of side chain functional groups, we used several amino acids as precursors in this reaction/exchange procedure. The performance of DTC-ligands, as evaluated by the preservation of luminescence and colloidal stability, varied widely among amino precursors. For the best DTC-ligand and QD combinations, the quantum yield of the water-soluble QDs rivaled that of the original hydrophobic-capped QDs dispersed in organic solvents. The mean density of DTC-ligands per nanocrystal was estimated through a mass balance calculation which suggested nearly complete coverage of the available nanocrystal surface. The accessibility of the QD surface was evaluated by self-assembly of His-tagged dye-labeled proteins and peptides using fluorescence resonance energy transfer. DTC-capped QDs were also exposed to cell cultures to evaluate their stability and potential use for biological applications. In general, DTC-capped CdSe-ZnS QDs have many advantages over other water-soluble QD formulations and provide a flexible chemistry for controlling the QD surface functionalization. Despite previous literature reports of DTC-stabilized nanocrystals, this study is the first formal investigation of a biphasic exchange method for generating biocompatible core-shell QDs. PMID:21053924

  7. Generating Water-Soluble Noxious Gases: An Overhead Projector Demonstration

    NASA Astrophysics Data System (ADS)

    Solomon, Sally; Oliver-Hoyo, Maria; Hur, Chinhyu


    A simple, inexpensive apparatus to generate and collect water-soluble noxious gases as an overhead projector demonstration can be made from two small beakers and a Petri dish. The detection and generation of sulfur dioxide and nitrogen dioxide are described. Sulfur dioxide dissolved in water is detected using an acid-base indicator, decolorizing of anthocyanin, or reduction of permanganate. The SO2 is generated by addition of sulfite or bisulfite to a strong acid or by the addition of concentrated sulfuric acid to sugars. Nitrogen dioxide is generated by mixing copper and nitric acid and detected using an acid-base indicator.

  8. Correlation of octanol/water solubility ratios and partition coefficients

    SciTech Connect

    Pinsuwan, S.; Li, A.; Yalkowsky, S.H.


    The partition coefficient between octanol and water in an important physicochemical parameter for characterizing the lipophilicity or hydrophobicity of a compound and it is used in many fields, especially in the environmental and pharmaceutical sciences. The octanol/water solubility ratio (S{sub o}/S{sub W}) was found to be highly correlated with the octanol/water partition coefficient (K{sub ow}) of 82 pharmaceutically and environmentally relevant compounds. The solubility ratio gives comparable estimates to that of the group contribution (log P(calcd)) method for estimating the partition coefficient of the compounds used in this study.

  9. Applications of water-soluble polymers in the oil field

    SciTech Connect

    Chatterji, J.; Borchardt, J.K.


    Water-soluble polymers commonly used in the oil field are reviewed. The properties of guar, guar derivatives, cellulose derivatives, xanthan gum, locust bean gum, starches, and synthetic polymers, especially polyacrylamides, are discussed and related to chemical structures of the polymers. Original data comparing polymer solution viscosity properties under identical conditions are presented. These data include effect of polymer concentration on solution viscosity, temperature effect on solution viscosity, viscosity in acidic solution, and polymer solution viscosity in the presence of a hemicellulase enzyme. 105 refs.

  10. Picosecond dynamics in water-soluble azobenzene-peptides

    NASA Astrophysics Data System (ADS)

    Satzger, H.; Root, C.; Renner, C.; Behrendt, R.; Moroder, L.; Wachtveitl, J.; Zinth, W.


    Ultrafast absorption changes are recorded for water-soluble cyclic azobenzene peptides containing the photoswitch (4-aminomethyl)-phenyl-azobenzoic acid (AMPB) and a bioactive peptide motif. They can be separated into the fast reactions in the AMPB chromophore and the slower response of the peptide moiety. While the fastest reactions display similar time constants as observed for AMPB peptides dissolved in DMSO the slower reaction dynamics assigned to vibrational cooling and motions of the peptide moiety are faster in water by a factor of up to two. The changes in the reaction times are explained by solvent heat capacity and viscosity.

  11. Water soluble fluorescence quantum dot probe labeling liver cancer cells.


    Chang, Baoxing; Yang, Xianjun; Wang, Fang; Wang, Yinsong; Yang, Rui; Zhang, Ning; Wang, Baiqi


    Water soluble quantum dots (QDs) have been prepared by hydrothermal method and characterized by ultraviolet irradiation, XRD, TEM, UV-Vis absorption spectrometer and fluorescence spectrometer. Then the QD-antibody-AFP probes (QD-Ab-AFP) were synthesized by chemical process and specifically labeled AFP antigen in PLC/PRF/5 liver cancer cells. The results showed that the QDs were cubic structure and had excellent optical properties. Moreover, the QD-Ab-AFP with good stability could specifically label liver cancer cells. This work provides strong foundation for further studying and developing new approach to detect liver cancer at early stage. PMID:23888351

  12. New water-soluble carbamate ester derivatives of resveratrol.


    Mattarei, Andrea; Carraro, Massimo; Azzolini, Michele; Paradisi, Cristina; Zoratti, Mario; Biasutto, Lucia


    Low bioavailability severely hinders exploitation of the biomedical potential of resveratrol. Extensive phase-II metabolism and poor water solubility contribute to lowering the concentrations of resveratrol in the bloodstream after oral administration. Prodrugs may provide a solution-protection of the phenolic functions hinders conjugative metabolism and can be exploited to modulate the physicochemical properties of the compound. We report here the synthesis and characterization of carbamate ester derivatives of resveratrol bearing on each nitrogen atom a methyl group and either a methoxy-poly(ethylene glycol)-350 (mPEG-350) or a butyl-glucosyl promoiety conferring high water solubility. Ex vivo absorption studies revealed that the butyl-glucosyl conjugate, unlike the mPEG-350 one, is able to permeate the intestinal wall. In vivo pharmacokinetics confirmed absorption after oral administration and showed that no hydrolysis of the carbamate groups takes place. Thus, sugar groups can be attached to resveratrol to obtain soluble derivatives maintaining to some degree the ability to permeate biomembranes, perhaps by facilitated or active transport. PMID:25275336

  13. Chelating water-soluble polymers for waste minimization

    SciTech Connect

    Smith, B.; Cournoyer, M.; Duran, B.; Ford, D.; Gibson, R.; Lin, M.; Meck, A.; Robinson, P.; Robison, T.


    Within the DOE complex and in industry there is a tremendous need for advanced metal ion recovery and waste minimization techniques. This project sought to employ capabilities for ligand-design and separations chemistry in which one can develop and evaluate water- soluble chelating polymers for recovering actinides and toxic metals from various process streams. Focus of this work was (1) to develop and select a set of water-soluble polymers suitable for a selected waste stream and (2) demonstrate this technology in 2 areas: removal of (a) actinides and toxic RCRA metals from waste water and (b) recovery of Cu and other precious metals from industrial process streams including from solid catalysts and aqueous waste streams. The R&D was done in 4 phases for each of the 2 target areas: polymer synthesis for scaleup, equipment assembly, process demonstration at a DOE or industrial site, and advanced ligand/polymer synthesis. The TA- 50 site at Los Alamos was thought to be appropriate due to logistics and to its being representative of similar problems throughout the DOE complex.

  14. Estrogenic profile on a water-soluble estrogen, estrazinol hydrobromide.


    Rassaert, C L; DiPasquale, G; Giannina, T; Manning, J P; Meli, A


    The estrogenic properties of estrazinol hydrobromide (EZ), a water-soluble estrogen, were compared with those of Premarin (PR), another water-soluble estrogen preparation consisting of conjugated equine estrogens. Estradiol-17beta, estra-1,3,5(10)-triene-3,17beta-diol (E), and ethinyl estradiol, 17alpha-ethinyl-1,3,5 (10)-estratriene-3,17beta-diol (EE) were used as reference standards. Subcutaneous progesterone (400 mcg) given to rabbits primed with comparable subcutaneous doses of either E or EE produced full secretory changes of the endometrium, while such a transformation could not be elicited in orally primed animals regardless of the estrogen used. The biological profile or orally administered EZ was very similar to that of oral EE and different from oral PR. Howerver, the oral EZ-induced morphological changes of the rabbit endometrium appeared somewhat different from those produced by oral EE. The findings indicated that following oral administration, EZ-induced endometrial transformation is more "normal" and/or adequate than the changes produced by either EE or PR. PMID:4368700

  15. Adhesive evaluation of water-soluble LARC-TPI

    NASA Technical Reports Server (NTRS)

    Progar, Donald J.; Pike, Roscoe A.


    The water-soluble polyimide, identified as TPI(MTC)/H2O, was evaluated as a high temperature thermoplastic adhesive for bonding Ti-6Al-4V and comparing those results primarily with results reported in earlier work with the polyamic-acid/diglyme material. The lap shear strength test was the primary test performed to evaluate the adhesive before (controls) and after thermal exposure in air at 204 C for up to 5000 hours and after a 72 hour water-boil exposure. Lap shear strengths were determined at RT, 177, 204, and 232 C. The adhesive was also characterized after fracture by determining the glass transition temperature as well as defining the mode of failure by visual observation. In general, the results indicate that the TPI(MTC)/H2O retains high lap shear strengths after thermal exposure but had reduced strengths after the water-boil exposure. All failures were cohesive. The TPI(MTC)/H2O compared very well with previous data reported for the standard polyamic-acid/diglyme LARC-TPI results, and therefore, shows promise as a water-soluble adhesive for use in various applications.

  16. Novel Water-Soluble Mucoadhesive Carbosilane Dendrimers for Ocular Administration.


    Bravo-Osuna, I; Vicario-de-la-Torre, M; Andrés-Guerrero, V; Sánchez-Nieves, J; Guzmán-Navarro, M; de la Mata, F J; Gómez, R; de Las Heras, B; Argüeso, P; Ponchel, G; Herrero-Vanrell, R; Molina-Martínez, I T


    The purpose of this research was to determine the potential use of water-soluble anionic and cationic carbosilane dendrimers (generations 1-3) as mucoadhesive polymers in eyedrop formulations. Cationic carbosilane dendrimers decorated with ammonium -NH3(+) groups were prepared by hydrosylilation of Boc-protected allylamine and followed by deprotection with HCl. Anionic carbosilane dendrimers with terminal carboxylate groups were also employed in this study. In vitro and in vivo tolerance studies were performed in human ocular epithelial cell lines and rabbit eyes respectively. The interaction of dendrimers with transmembrane ocular mucins was evaluated with a surface biosensor. As proof of concept, the hypotensive effect of a carbosilane dendrimer eyedrop formulation containing acetazolamide (ACZ), a poorly water-soluble drug with limited ocular penetration, was tested after instillation in normotensive rabbits. The methodology used to synthesize cationic dendrimers avoids the difficulty of obtaining neutral -NH2 dendrimers that require harsher reaction conditions and also present high aggregation tendency. Tolerance studies demonstrated that both prototypes of water-soluble anionic and cationic carbosilane dendrimers were well tolerated in a range of concentrations between 5 and 10 μM. Permanent interactions between cationic carbosilane dendrimers and ocular mucins were observed using biosensor assays, predominantly for the generation-three (G3) dendrimer. An eyedrop formulation containing G3 cationic carbosilane dendrimers (5 μM) and ACZ (0.07%) (289.4 mOsm; 5.6 pH; 41.7 mN/m) induced a rapid (onset time 1 h) and extended (up to 7 h) hypotensive effect, and led to a significant increment in the efficacy determined by AUC0(8h) and maximal intraocular pressure reduction. This work takes advantage of the high-affinity interaction between cationic carbosilane dendrimers and ocular transmembrane mucins, as well as the tensioactive behavior observed for these

  17. Biological activities of water-soluble fullerene derivatives

    NASA Astrophysics Data System (ADS)

    Nakamura, S.; Mashino, T.


    Three types of water-soluble fullerene derivatives were synthesized and their biological activities were investigated. C60-dimalonic acid, an anionic fullerene derivative, showed antioxidant activity such as quenching of superoxide and relief from growth inhibition of E. coli by paraquat. C60-bis(7V,7V-dimethylpyrrolidinium iodide), a cationic fullerene derivative, has antibacterial activity and antiproliferative effect on cancer cell lines. The mechanism is suggested to be respiratory chain inhibition by reactive oxygen species produced by the cationic fullerene derivative. Proline-type fullerene derivatives showed strong inhibition activities on HIV-reverse transcriptase. The IC50 values were remarkably lower than nevirapine, a clinically used anti-HIV drug. Fullerene derivatives have a big potential for a new type of lead compound to be used as medicine.

  18. Transfer molding of nanoscale oxides using water-soluble templates.


    Bass, John D; Schaper, Charles D; Rettner, Charles T; Arellano, Noel; Alharbi, Fahhad H; Miller, Robert D; Kim, Ho-Cheol


    We report a facile method for creating nanoscopic oxide structures over large areas that is capable of producing high aspect ratio nanoscale structures with feature sizes below 50 nm. A variety of nanostructured oxides including TiO(2), SnO(2) and organosilicates are formed using sol-gel and nanoparticle precursors by way of molding with water-soluble polymeric templates generated from silicon masters. Sequential stacking techniques are developed that generate unique 3-dimensional nanostructures with combinatorially mixed geometries, scales, and materials. Applicable to a variety of substrates, this scalable method allows access to a broad range of new thin film morphologies for applications in devices, catalysts, and functional surface coatings. PMID:21469708

  19. Biodegradable fibre scaffolds incorporating water-soluble drugs and proteins.


    Ma, J; Meng, J; Simonet, M; Stingelin, N; Peijs, T; Sukhorukov, G B


    A new type of biodegradable drug-loaded fibre scaffold has been successfully produced for the benefit of water-soluble drugs and proteins. Model drug loaded calcium carbonate (CaCO3) microparticles incorporated into poly(lactic acid-co-glycolic acid) (PLGA) fibres were manufactured by co-precipitation of CaCO3 and the drug molecules, followed by electrospinning of a suspension of such drug-loaded microparticles in a PLGA solution. Rhodamine 6G and bovine serum albumin were used as model drugs for our release study, representing small bioactive molecules and protein, respectively. A bead and string structure of fibres was achieved. The drug release was investigated with different drug loadings and in different pH release mediums. Results showed that a slow and sustained drug release was achieved in 40 days and the CaCO3 microparticles used as the second barrier restrained the initial burst release. PMID:26155976

  20. Improved water-soluble polymers for enhanced recovery of oil

    SciTech Connect

    Martin, F.D.; Hatch, M.J.; Shepitka, J.S.; Ward, J.S.


    Two principal types of polymers have been used extensively for enhanced recovery of crude oil: partially hydrolyzed polyacrylamide (HPAM) and xanthan gum. Because of its lower cost, HPAM is being used in a majority of the field projects when water-soluble polymers are applied. However, HPAM does lose viscosity in brines, particularly when divalent ions are present, and is susceptible to mechanical degradation under high shear conditions. Although many different polymer structures were evaluated in the laboratory tests, the main focus consisted of modifying the structure of HPAM and observing the effects on brine and shear stability. Testing of these analogs provided a systematic correlation of polymer structure with polymer performance so that improved compounds could be developed. 33 references.

  1. Self-assembly of water-soluble nanocrystals


    Fan, Hongyou; Brinker, C. Jeffrey; Lopez, Gabriel P.


    A method for forming an ordered array of nanocrystals where a hydrophobic precursor solution with a hydrophobic core material in an organic solvent is added to a solution of a surfactant in water, followed by removal of a least a portion of the organic solvent to form a micellar solution of nanocrystals. A precursor co-assembling material, generally water-soluble, that can co-assemble with individual micelles formed in the micellar solution of nanocrystals can be added to this micellar solution under specified reaction conditions (for example, pH conditions) to form an ordered-array mesophase material. For example, basic conditions are used to precipitate an ordered nanocrystal/silica array material in bulk form and acidic conditions are used to form an ordered nanocrystal/silica array material as a thin film.

  2. Solubilization of poorly water-soluble drugs using solid dispersions.


    Tran, Thao T-D; Tran, Phuong H-L; Khanh, Tran N; Van, Toi V; Lee, Beom-Jin


    Many new drugs have been discovered in pharmaceutical industry and exposed their surprised potential therapeutic effects. Unfortunately, these drugs possess low absorption and bioavailability since their solubility limitation in water. Solid dispersion (SD) is the current technique gaining so many attractions from scientists due to its effect on improving solubility and dissolution rate of poorly water-soluble drugs. A number of patents including the most recent inventions have been undertaken in this review to address various respects of this strategy in solubilization of poorly watersoluble drugs including type of carriers, preparation methods and view of technologies used to detect SD properties and mechanisms with the aim to accomplish a SD not only effective on enhanced bioavailability but also overcome difficulties associated with stability and production. Future prospects are as well discussed with an only hope that many developments and researches in this field will be successfully reached and contributed to commercial use for treatment as much as possible. PMID:23244679

  3. Reactivity of Metal Ions Bound to Water-Soluble Polymers

    SciTech Connect

    Sauer, N.N.; Watkins, J.G.; Lin, M.; Birnbaum, E.R.; Robison, T.W.; Smith, B.F.; Gohdes, J.W.; McDonald, J.G.


    The intent of this work is to determine the effectiveness of catalysts covalently bound to polymers and to understand the consequences of supporting the catalysts on catalyst efficiency and selectivity. Rhodium phosphine complexes with functional groups for coupling to polymers were prepared. These catalyst precursors were characterized using standard techniques including IR, NMR, and elemental analysis. Studies on the modified catalysts showed that they were still active hydrogenation catalysts. However, tethering of the catalysts to polyamines gave systems with low hydrogenation activity. Analogous biphasic systems were also explored. Phosphine ligands with a surfactant-like structure have been synthesized and used to prepare catalytically active complexes of palladium. The palladium complexes were utilized in Heck-type coupling reactions (e.g. coupling of iodobenzene and ethyl acrylate to produce ethyl cinnamate) under vigorously stirred biphasic reaction conditions, and were found to offer superior performance over a standard water-soluble palladium catalyst under analogous conditions.

  4. Solvent-Free Polymerization of L-Aspartic Acid in the Presence of D-Sorbitol to Obtain Water Soluble or Network Copolymers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    L-aspartic acid was thermally polymerized in the presence of D-sorbitol with the goal of synthesizing new, higher molecular weight water soluble and absorbent copolymers. No reaction occurred when aspartic acid alone was heated at 170 or 200 degrees C. In contrast, heating sorbitol and aspartic ac...

  5. Water-soluble polymers for recovery of metal ions from aqueous streams


    Smith, Barbara F.; Robison, Thomas W.


    A process of selectively separating a target metal contained in an aqueous solution by contacting the aqueous solution containing a target metal with an aqueous solution including a water-soluble polymer capable of binding with the target metal for sufficient time whereby a water-soluble polymer-target metal complex is formed, and, separating the solution including the water-soluble polymer-target metal complex from the solution is disclosed.

  6. [Emission Characteristics of Water-Soluble Ions in Fumes of Coal Fired Boilers in Beijing].


    Hu, Yue-qi; Ma, Zhao-hui; Feng, Ya-jun; Wang, Chen; Chen, Yuan-yuan; He, Ming


    Selecting coal fired boilers with typical flue gas desulfurization and dust extraction systems in Beijing as the study objects, the issues and characteristics of the water-soluble ions in fumes of coal fired boilers and theirs influence factors were analyzed and evaluated. The maximum mass concentration of total water-soluble ions in fumes of coal fired boilers in Beijing was 51.240 mg x m(-3) in the benchmark fume oxygen content, the minimum was 7.186 mg x m(-3), and the issues of the water-soluble ions were uncorrelated with the fume moisture content. SO4(2-) was the primary characteristic water-soluble ion for desulfurization reaction, and the rate of contribution of SO4(2-) in total water-soluble ions ranged from 63.8% to 81.0%. F- was another characteristic water-soluble ion in fumes of thermal power plant, and the rate of contribution of F- in total water-soluble ions ranged from 22.2% to 32.5%. The fume purification technologies significantly influenced the issues and the emission characteristics of water-soluble ions in fumes of coal fired boilers. Na+ was a characteristic water-soluble ion for the desulfurizer NaOH, NH4+ and NO3+ were characteristic for the desulfurizer NH4HCO3, and Mg2+ was characteristic for the desulfurizer MgO, but the Ca2+ emission was not increased by addition of the desulfurizer CaO or CaCO3 The concentrations of NH4+ and NO3- in fumes of thermal power plant were lower than those in fumes of industrial or heating coal fired boilers. The form of water-soluble ions was significantly correlated with fume temperature. The most water-soluble ions were in superfine state at higher fume temperature and were not easily captured by the filter membrane. PMID:26387296

  7. Photochemical and biological degradation of water-soluble FWAs.


    Guglielmetti, L


    A study was made of the photochemical and biological degradation of two water-soluble fluorescent whitening agents (FWAs): the disodium 4,4'-bis(2-sulfostyryl)-biphenyl (1) and the disodium 4,4-bis ([4-anilino-6-(N-methyl-N-2-hydroxyethyl)amino 1,3,5-triazin-2-yl]amino)stilbene-2,2'-disulfonate (2). Each represents an important class of detergent fluorescent whitening agents. The photochemical degradation of (1) was studied by irradiating diluted aqueous solutions of this compound with a low intensity high pressure mercury vapor lamp. From the intermediate, as well as the ultimate photodegradation products isolated, it can be infered that photodegradation of (1) followed the proposed scheme. The biologica degradation of (1) and (2) by activated sludge under aerobic conditions was studied using equipment similar to that proposed by the OECD for determining the biodegradation of anionic synthetic surface active agents. Under the conditons applied, both FWAs were slowly biodegraded, within 30 days, whereas the photodegradation products of (1) were completely biodegraded within 14 days. PMID:6265

  8. Monosaccharides as Versatile Units for Water-Soluble Supramolecular Polymers.


    Leenders, Christianus M A; Jansen, Gijs; Frissen, Martijn M M; Lafleur, René P M; Voets, Ilja K; Palmans, Anja R A; Meijer, E W


    We introduce monosaccharides as versatile water-soluble units to compatibilise supramolecular polymers based on the benzene-1,3,5-tricarboxamide (BTA) moiety with water. A library of monosaccharide-based BTAs is evaluated, varying the length of the alkyl chain (hexyl, octyl, decyl and dodecyl) separating the BTA and saccharide units, as well as the saccharide units (α-glucose, β-glucose, α-mannose and α-galactose). In all cases, the monosaccharides impart excellent water compatibility. The length of the alkyl chain is the determining factor to obtain either long, one-dimensional supramolecular polymers (dodecyl spacer), small aggregates (decyl spacer) or molecularly dissolved (octyl and hexyl) BTAs in water. For the BTAs comprising a dodecyl spacer, our results suggest that a cooperative self-assembly process is operative and that the introduction of different monosaccharides does not significantly change the self- assembly behaviour. Finally, we investigate the potential of post-assembly functionalisation of the formed supramolecular polymers by taking advantage of dynamic covalent bond formation between the monosaccharides and benzoxaboroles. We observe that the supramolecular polymers readily react with a fluorescent benzoxaborole derivative permitting imaging of these dynamic complexes by confocal fluorescence microscopy. PMID:26890574

  9. Water-soluble reaction products from ozonolysis of grasses

    SciTech Connect

    Morrison, W.H. III; Akin, D.E. )


    Ozone has been used to pretreat agricultural byproducts with the aim of increasing nutritive value for ruminants. However, not all treatments with ozone result in enhanced digestibility, suggesting reaction products from ozone treatment of plants might inhibit rumen microbial activity. Coastal Bermuda grass (Cynodon dactylon L. Pers.) (CBG) and Kentucky-31 tall fescue (Festuca arundinacea Schreb.) (K-31) were treated with ozone and the water-soluble products determined. The following acids were identified: caproic, levulinic, p-hydroxybenzoic, vinillic, azelaic, and malonic. In addition, vanillin and p-hydroxybenzaldehyde were also identified. Ozone treatment of the cell walls of CBG produced mainly p-hydroxybenzoic acid, vanillic acid, azelaic acid, p-hydroxybenzaldehyde, and vanillin. Ozone treatment of K-31 cell walls produced levulinic acid in addition to those products found from CBG cell walls. The production of vanillin and p-hydroxybenzaldehyde, which have been shown to be especially toxic to rumen microorganisms, offers an explanation for the negative affects of ozone treatment on forage.

  10. [Functionally-relevant conformational dynamics of water-soluble proteins].


    Novikov, G V; Sivozhelezov, V S; Shaĭtan, K V


    A study is reported of the functional-relevant dynamics of three typical water-soluble proteins: Calmodulin, Src-tyrosine kinase as well as repressor of Trp operon. Application of the state-of-art methods of structural bioinformatics allowed to identify dynamics seen in the X-ray structures of the investigated proteins associated with their specific biological functions. In addition, Normal Mode analysis technique revealed the most probable directions of the functionally-relevant motions for all that proteins were also predicted. Importantly, overall type of the motions observed on the lowest-frequency modes was very similar to the motions seen from the analysis of the X-ray data of the examined macromolecules. Thereby it was shown that the large-scale as well as local conformational motions of the proteins might be predetermined already at the level of their tertiary structures. In particular, the determining factor might be the specific fold of the alpha-helixes. Thus functionally-relevant in vivo dynamics of the investigated proteins might be evolutionally formed by means of natural selection at the level of the spatial topology. PMID:23705506

  11. Soft water-soluble microgel dispersions: structure and rheology.


    Omari, A; Tabary, R; Rousseau, D; Calderon, F Leal; Monteil, J; Chauveteau, G


    The size and structural characteristics of polyacrylamide-based water-soluble microgel dispersions were investigated by optical and rheological methods. Microgel hydrodynamic radii Rh were measured by light scattering and derived from intrinsic shear viscosity [eta]0. The variations of Rh3 and [eta]0 with the crosslink density Nx, follow the scaling law Rh3 congruent withNx(-alpha) with alpha close to 0.63, in good agreement with the simple structural model proposed in this paper showing how the exact value of alpha depends on inner structural details of the microgel. The plateau viscosity versus particle apparent volume fraction shows a monotonous change from hard sphere dispersions (high crosslink density of microgels) to flexible linear polymer solutions. Measurements of the first normal stress difference N1 show that increasing the microgel crosslink density affects the system viscosity more than its elasticity. Under oscillatory shear flow, loss and storage moduli undergo both qualitative and quantitative changes with crosslink density. At moderate concentrations, the elastic modulus is the most affected and its slope in low frequency regime decreases from two to less than one as Nx increases. We discuss the experimental results within the frame of knowledge on linear, branched polymer solutions and soft microgel suspensions. PMID:16928380

  12. Stability of water-soluble carbodiimides in aqueous solution.


    Gilles, M A; Hudson, A Q; Borders, C L


    A dimethylbarbituric acid reagent has been used to follow the kinetics of loss of two water-soluble carbodiimides, 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and the structurally related 1-ethyl-3-(4-azonia-4,4-dimethylpentyl) carbodiimide (EAC), in aqueous solution as a function of pH and added chemical reagents. In 50 mM 2-(N-morpholino)ethanesulfonic acid at 25 degrees C, EDC has t1/2 values of 37, 20, and 3.9 h at pH 7.0, 6.0, and 5.0, respectively, while the corresponding values for EAC are 12, 2.9, and 0.32 h. Iodide, bromide, or chloride, at 0.1 M, has very little or no effect on carbodiimide stability. However, 0.1 M glycine methyl ester or 0.1 M ethylenediamine causes a significant increase in the rate of loss of EAC and EDC, while the presence of 0.1 M phosphate, 0.1 M hydroxylamine, or 0.01 M ATP decreases the half-lives to less than or equal to 0.4 h at all pH values. PMID:2158246

  13. Water soluble quantum dot nanoclusters: energy migration in artifical materials.


    Oh, Megan H J; Gentleman, Darcy J; Scholes, Gregory D


    Energy migration in self-assembled, water soluble, quantum dot (QD) nanoclusters is reported. These spherical nanoclusters are composed of CdSe QDs bound together by pepsin, a digestive enzyme found in mammals. A structural model for the clusters is suggested, based on scanning transmission electron microscopy, as well as dynamic light scattering and small angle X-ray scattering. Cluster sizes range from 100 to 400 nm in diameter and show a close-packed interior structure. Optical characterization of the absorption and emission spectra of the clusters is reported, finding photoluminescence quantum yields of up to approximately 60% in water for clusters made from core-shell CdSe-ZnS QDs. Clusters prepared from two different size populations of CdSe QD samples (3 and 4 nm in diameter) demonstrate energy migration and trapping. Resonance energy transfer (RET), from small to large dots within the QD-pepsin cluster, is observed by monitoring the quenching of the small donor dot fluorescence along with enhancement of the large acceptor dot fluorescence. PMID:17091158

  14. Water-soluble fullerene materials for bioapplications: photoinduced reactive oxygen species generation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The photoinduced reactive oxygen species (ROS) generation from several water-soluble fullerenes was examined. Macromolecular or small molecular water-soluble fullerene complexes/derivatives were prepared and their 1O2 and O2•- generation abilities were evaluated by EPR spin-trapping methods. As a r...

  15. Preparation of biomaterials on the basis of a water-soluble cellulose acetate

    NASA Astrophysics Data System (ADS)

    Akmalova, G. Yu.; Gulyamova, N. S.; Zainutdinov, U. N.; Rakhmanberdiev, G. R.; Negmatova, K. S.; Negmatova, M. I.


    Biomaterials were obtained on the basis of water-soluble cellulose acetate and diterpenoids group of plants Lagohulusa intoxicating having hemostatic properties. It is established that these biomaterials on the basis of water-soluble cellulose acetate and lagohilina (or lagohirzina) had increased hemostatic activity and reduce parenchymal hemorrhage 5-6 times compared to control.

  16. 40 CFR 799.6784 - TSCA water solubility: Column elution method; shake flask method.

    Code of Federal Regulations, 2011 CFR


    ... 40 Protection of Environment 32 2011-07-01 2011-07-01 false TSCA water solubility: Column elution... AND MIXTURE TESTING REQUIREMENTS Product Properties Test Guidelines § 799.6784 TSCA water solubility... here may not yet be optimal. This method is intended for material with solubilities below...

  17. 40 CFR 799.6784 - TSCA water solubility: Column elution method; shake flask method.

    Code of Federal Regulations, 2014 CFR


    ... 40 Protection of Environment 32 2014-07-01 2014-07-01 false TSCA water solubility: Column elution... AND MIXTURE TESTING REQUIREMENTS Product Properties Test Guidelines § 799.6784 TSCA water solubility... here may not yet be optimal. This method is intended for material with solubilities below...

  18. 40 CFR 799.6784 - TSCA water solubility: Column elution method; shake flask method.

    Code of Federal Regulations, 2012 CFR


    ... 40 Protection of Environment 33 2012-07-01 2012-07-01 false TSCA water solubility: Column elution... AND MIXTURE TESTING REQUIREMENTS Product Properties Test Guidelines § 799.6784 TSCA water solubility... here may not yet be optimal. This method is intended for material with solubilities below...

  19. Vertical distribution and water solubility of phosphorus and heavy metals in sediments of the St. Lucie Estuary, South Florida, USA

    NASA Astrophysics Data System (ADS)

    He, Z. L.; Zhang, M.; Stoffella, P. J.; Yang, X. E.


    Accumulation and distribution of heavy metals and phosphorus in sediments impact water quality. There has been an increasing concern regarding fish health in the St. Lucie Estuary, which is related to increased inputs of nutrients and metals in recent decades. To investigate vertical changes of contaminants (P, Cd, Cr, Co, Cu, Ni, Pb, Zn, and Mn) in sediments of the St. Lucie Estuary in South Florida, 117 layer samples from six of the 210 to 420 cm depth cores were analyzed for their total and water-soluble P and heavy metals, clay, total Fe, Al, K, Ca, Mg, Na, and pH. Principal component analysis (PCA) was used in two sets of analytical data (total and water-soluble contaminant concentrations) to document changes of contaminants in each core of sediments. The PCA of total contaminants and minerals resulted in two factors (principal components). The first and second factors accounted for 61.7 and 17.2 % of the total variation in all variables, and contrast indicators associated with contaminants of P, Cd, Co, Cr, Ni, Pb, Zn, and Mn and accumulation of Fe and Al oxides, respectively. The first factor could be used for overall assessment of P and heavy metal contamination, and was higher in the upper 45-90 cm than the lower depths of each core. The concentrations of P and heavy metals in the surface layers of sediments significantly increased, as compared with those in the sediments deeper than 45-90 cm. The PCA of water-soluble contaminants developed two factors. The second factor (Cu-P) was higher in the upper than the lower depths of the sediment, whereas the highest score of the first factor (Cd-Co-Cr-Ni-Pb-Zn-Mn) occurred below 100 cm. The water-soluble Cu and P concentrations were mainly dependent on their total concentrations in the sediments, whereas the water-soluble Cd, Co, Cr, Ni, Pb, Zn, and Mn concentrations were mainly controlled by pH.

  20. Photochemistry within a water-soluble organic capsule.


    Ramamurthy, Vaidhyanathan


    Photochemistry along with life as we know it originated on earth billions of years ago. Supramolecular Photochemistry had its beginning when plants that sustain life began transforming water into oxygen by carrying out light initiated reactions within highly organized assemblies. Prompted by the efforts of J. Priestly (photosynthesis), F. Sestini, S. Cannizaro, and C. Liebermann (solid-state photochemistry of santonin, quinones, and cinnamic acid), orderly scientific investigations of the link between light absorption by matter and molecules and the chemical and physical consequences began in the mid-1700s. By 1970 when Molecular Photochemistry had matured, it was clear that controlling photochemical reactions by conventional methods of varying reaction parameters like temperature and pressure would be futile due to the photoreactions' very low activation energies and enthalpies. During the last 50 years, the excited state behavior of molecules has been successfully manipulated with the use of confining media and weak interactions between the medium and the reactant molecule. In this context, with our knowledge from experimentation with micelles, cyclodextrins (CD), cucurbitruils (CB), calixarenes (CA), Pd nanocage, crystals, and zeolites as media, we began about a decade ago to explore the use of a new water-soluble synthetic organic cavitand, octa acid (OA) as a reaction container. The uniqueness of OA as an organic cavitand lies in that two OA molecules form a closed hydrophobic capsule to encapsulate water-insoluble guest molecule(s). The ability to include a large number of guest molecules in OA has provided an opportunity to examine the excited state chemistry of organic molecules in a hydrophobic, confined environment. OA distinguishes itself from the well-known cavitands CD and CB by its active reaction cavity absorbing UV-radiation between 200 and 300 nm and serving as energy, electron, and hydrogen donor. The freedom of guest molecules in OA, between that

  1. Water-soluble ruthenium complexes bearing activity against protozoan parasites.


    Sarniguet, Cynthia; Toloza, Jeannette; Cipriani, Micaella; Lapier, Michel; Vieites, Marisol; Toledano-Magaña, Yanis; García-Ramos, Juan Carlos; Ruiz-Azuara, Lena; Moreno, Virtudes; Maya, Juan Diego; Azar, Claudio Olea; Gambino, Dinorah; Otero, Lucía


    Parasitic illnesses are major causes of human disease and misery worldwide. Among them, both amebiasis and Chagas disease, caused by the protozoan parasites, Entamoeba histolytica and Trypanosoma cruzi, are responsible for thousands of annual deaths. The lack of safe and effective chemotherapy and/or the appearance of current drug resistance make the development of novel pharmacological tools for their treatment relevant. In this sense, within the framework of the medicinal inorganic chemistry, metal-based drugs appear to be a good alternative to find a pharmacological answer to parasitic diseases. In this work, novel ruthenium complexes [RuCl2(HL)(HPTA)2]Cl2 with HL=bioactive 5-nitrofuryl containing thiosemicarbazones and PTA=1,3,5-triaza-7-phosphaadamantane have been synthesized and fully characterized. PTA was included as co-ligand in order to modulate complexes aqueous solubility. In fact, obtained complexes were water soluble. Their activity against T. cruzi and E. histolytica was evaluated in vitro. [RuCl2(HL4)(HPTA)2]Cl2 complex, with HL4=N-phenyl-5-nitrofuryl-thiosemicarbazone, was the most active compound against both parasites. In particular, it showed an excellent activity against E. histolytica (half maximal inhibitory concentration (IC50)=5.2 μM), even higher than that of the reference drug metronidazole. In addition, this complex turns out to be selective for E. histolytica (selectivity index (SI)>38). The potential mechanism of antiparasitic action of the obtained ruthenium complexes could involve oxidative stress for both parasites. Additionally, complexes could interact with DNA as second potential target by an intercalative-like mode. Obtained results could be considered a contribution in the search for metal compounds that could be active against multiple parasites. PMID:24740394

  2. Non-ionic surfactant vesicles in pulmonary glucocorticoid delivery: characterization and interaction with human lung fibroblasts.


    Marianecci, Carlotta; Paolino, Donatella; Celia, Christian; Fresta, Massimo; Carafa, Maria; Alhaique, Franco


    Non-ionic surfactant vesicles (NSVs) were proposed for the pulmonary delivery of glucocorticoids such as beclomethasone dipropionate (BDP) for the treatment of inflammatory lung diseases, e.g. asthma, chronic obstructive pulmonary disease and various type of pulmonary fibrosis. The thin layer evaporation method followed by sonication was used to prepare small non-ionic surfactant vesicles containing beclomethasone dipropionate. Light scattering experiments showed that beclomethasone dipropionate-loaded non-ionic surfactant vesicles were larger than unloaded ones and showed a significant (P<0.001) decrease of the zeta potential. The morphological analysis, by freeze-fracture transmission electron microscopy, showed the maintenance of a vesicular structure in the presence of the drug. The colloidal and storage stability were evaluated by Turbiscan Lab Expert, which evidenced the good stability of BDP-loaded non-ionic surfactant vesicles, thus showing no significant variations of mean size and no colloidal phase segregation. Primary human lung fibroblast (HLF) cells were used for in vitro investigation of vesicle tolerability, carrier-cell interaction, intracellular drug uptake and drug-loaded vesicle anti-inflammatory activity. The investigated NSVs did not show a significant cytotoxic activity at all incubation times for concentrations ranging from 0.01 to 1 μM. Confocal laser scanning microscopy showed vesicular carrier localization at the level of the cytoplasm compartment, where the glucocorticoid receptor (target site) is localized. BDP-loaded non-ionic surfactant vesicles elicited a significant improvement of the HLF intracellular uptake of the drug with respect to the free drug solution, drug/surfactant mixtures and empty vesicles used as references. The treatment of HLF cells with BDP-loaded non-ionic surfactant vesicles determined a noticeable increase of the drug anti-inflammatory activity by reducing the secretion of both constitutive and interleukin-1

  3. Investigating water soluble organic aerosols: Sources and evolution

    NASA Astrophysics Data System (ADS)

    Hecobian, Arsineh N.

    Many studies are being conducted on the different properties of organic aerosols (OA-s) as it is first emitted into the atmosphere and the consequent changes in these characteristics as OA-s age and secondary organic aerosol (SOA) is produced and in turn aged. This thesis attempts to address some of the significant and emerging issues that deal with the formation and transformation of water-soluble organic aerosols in the atmosphere. First, a proven method for the measurement of gaseous sulfuric acid, negative ion chemical ionization mass spectrometry (CIMS), has been modified for fast and sensitive measurements of particulate phase sulfuric acid (i.e. sulfate). The modifications implemented on this system have also been the subject of preliminary verifications for measurements of aerosol phase oxalic acid (an organic acid). Second, chemical and physical characteristics of a wide range of biomass-burning plumes intercepted by the NASA DC-8 research aircraft during the three phases of the ARCTAS experiment are presented here. A statistical summary of the emission (or enhancement) ratios relative to carbon monoxide is presented for various gaseous and aerosol species. Extensive investigations of fire plume evolutions were undertaken during the second part of this field campaign. For four distinct Boreal fires, where plumes were intercepted by the aircraft over a wide range of down-wind distances, emissions of various compounds and the effect of aging on them were investigated in detail. No clear evidence of production of secondary compounds (e.g., WSOC and OA) was observed. High variability in emissions between the different plumes may have obscured any clear evidence of changes in the mass of various species with increasing plume age. Also, the lack if tropospheric oxidizing species (e.g., O3 and OH) may have contributed to the lack of SOA formation. Individual intercepts of smoke plumes in this study were segregated by source regions. The normalized excess mixing

  4. Thin liquid films from aqueous solutions of non-ionic polymeric surfactants.


    Exerowa, Dotchi; Platikanov, Dimo


    The conditions of formation and stability of foam, emulsion, and wetting films from aqueous solutions of non-ionic polymeric surfactants have been established. Two types of polymeric surfactants - PEO-PPO-PEO three-block copolymers (A-B-A type) and hydrophobically modified inulin graft polymer (AB(n) type) - have been explored. Information about surface forces and nanoscale phenomena in aqueous films containing polymeric surfactants was obtained using the micro-interferometric technique and the Thin Liquid Film-Pressure Balance Technique. Two types of surface forces, which determine the stability of the foam and emulsion films, have been distinguished, namely: DLVO-forces at low electrolyte concentrations and non-DLVO-forces at high electrolyte concentrations. Non-DLVO-forces are steric surface forces of the brush-to-brush and loop-to-loop interaction type according to De Gennes. A substantial difference in the behavior of these two film types has been established and in the case of O/W emulsion films transitions to Newton black film (NBF) have been observed. These films are very stable and so are the respective emulsions. In contrast the wetting films are relatively thicker compared to emulsion films, and their thickness depends on the concentration of the AB(n) polymeric surfactant. The steric repulsion of the loops and tails of the polymeric surfactant determine the film thickness of wetting films on a hydrophilic solid surface. For solid surfaces with different degrees of hydrophobicity the wetting films are stable only at high polymer concentrations and low degree of hydrophobicity. Otherwise the films are unstable and rupture. Two types of bilayer emulsion films have been distinguished for the first time. One type is related to the brush-to-brush or loop-to-loop interactions according to De Gennes. The other type is a NBF where the forces are also steric between strongly hydrated brush and loops but they are short-range forces acting in a two

  5. Efficiency of non-ionic surfactants - EDTA for treating TPH and heavy metals from contaminated soil

    PubMed Central


    Introduction of fuel hydrocarbons and inorganic compounds (heavy metals) into the soil, resulting in a change of the soil quality, which is likely to affect use of the soil or endangering public health and ground water. This study aimed to determine a series of parameters to remediation of TPH and heavy metals contaminated soil by non-ionic surfactants- chelating agents washing process. In this experimental study, the effects of soil washing time, agitation speed, concentration of surfactant, chelating agent and pH on the removal efficiency were studied. The results showed that TPH removal by nonionic surfactants (Tween 80, Brij 35) in optimal condition were 70–80% and 60–65%, respectively. Addition of chelating agent (EDTA) significantly increases Cd and Pb removal. The washing of soil by non- ionic surfactants and EDTA was effective in remediation of TPH and heavy metals from contaminated soil, thus it can be recommended for remediation of contaminated soil. PMID:24359927

  6. Water-Soluble 2-Hydroxyisophthalamides for Sensitization of Lanthanide Luminescence

    SciTech Connect

    Samuel, Amanda P. S.; Moore, Evan G.; Melchior, Marco; Xu, Jide; Raymond, Kenneth N.


    A series of octadentate ligands featuring the 2-hydroxyisophthalamide (IAM) antenna chromophore (to sensitize Tb(III) and Eu(III) luminescence) has been prepared and characterized. The length of the alkyl amine scaffold that links the four IAM moieties has been varied in order to investigate the effect of the ligand backbone on the stability and photophysical properties of the Ln(III) complexes. The amine backbones utilized in this study are N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-ethane-1,2-diamine [H(2,2)-], N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-propane-1,3-diamine [H(3,2)-] and N,N,N{prime},N{prime}-tetrakis-(2-aminoethyl)-butane-1,4-diamine [H(4,2)-]. These ligands also incorporate methoxyethylene [MOE] groups on each of the IAM chromophores to increase their water solubility. The aqueous ligand protonation constants and Tb(III) and Eu(III) formation constants were determined from solution thermodynamic studies. The resulting values indicate that at physiological pH, the Eu(III) and Tb(III) complexes of H(2,2)-IAM-MOE and H(4,2)-IAM-MOE are sufficiently stable to prevent dissociation at nanomolar concentrations. The photophysical measurements for the Tb(III) complexes gave overall quantum yield values of 0.56, 0.39, and 0.52 respectively for the complexes with H(2,2)-IAM-MOE, H(3,2)-IAM-MOE and H(4,2)-IAM-MOE, while the corresponding Eu(III) complexes displayed significantly weaker luminescence, with quantum yield values of 0.0014, 0.0015, and 0.0058, respectively. Analysis of the steady state Eu(III) emission spectra provides insight into the solution symmetries of the complexes. The combined solubility, stability and photophysical performance of the Tb(III) complexes in particular make them well suited to serve as the luminescent reporter group in high sensitivity time-resolved fluoroimmunoassays.

  7. Water-Soluble 2-Hydroxyisophthalamides for Sensitization of Lanthanide Luminescence

    PubMed Central

    Samuel, Amanda P. S.; Moore, Evan G.; Melchior, Marco; Xu, Jide; Raymond, Kenneth N.


    A series of octadentate ligands featuring the 2-hydroxyisophthalamide (IAM) antenna chromophore (to sensitize Tb(III) and Eu(III) luminescence) has been prepared and characterized. The length of the alkyl amine scaffold that links the four IAM moieties has been varied in order to investigate the effect of the ligand backbone on the stability and photophysical properties of the Ln(III) complexes. The amine backbones utilized in this study are N,N,N',N'-tetrakis-(2-aminoethyl)-ethane-1,2-diamine [H(2,2)-], N,N,N',N'-tetrakis-(2-aminoethyl)-propane-1,3-diamine [H(3,2)-] and N,N,N',N'-tetrakis-(2-aminoethyl)-butane-1,4-diamine [H(4,2)-]. These ligands also incorporate methoxyethylene [MOE] groups on each of the IAM chromophores to increase their water solubility. The aqueous ligand protonation constants and Tb(III) and Eu(III) formation constants were determined from solution thermodynamic studies. The resulting values indicate that at physiological pH, the Eu(III) and Tb(III) complexes of H(2,2)-IAM-MOE and H(4,2)-IAM-MOE are sufficiently stable to prevent dissociation at nanomolar concentrations. The photophysical measurements for the Tb(III) complexes gave overall quantum yield values of 0.56, 0.39, and 0.52 respectively for the complexes with H(2,2)-IAM-MOE, H(3,2)-IAM-MOE and H(4,2)-IAM-MOE, while the corresponding Eu(III) complexes displayed significantly weaker luminescence, with quantum yield values of 0.0014, 0.0015, and 0.0058, respectively. Analysis of the steady state Eu(III) emission spectra provides insight into the solution symmetries of the complexes. The combined solubility, stability and photophysical performance of the Tb(III) complexes in particular make them well suited to serve as the luminescent reporter group in high sensitivity time-resolved fluoroimmunoassays. PMID:18671388

  8. Antioxidant Activity of Water-soluble Polysaccharides from Brasenia schreberi

    PubMed Central

    Xiao, Huiwen; Cai, Xueru; Fan, Yijun; Luo, Aoxue


    Objective: In order to investigate the antioxidant activities of polysaccharides (BPL-1 and BPL-2), one of the most important functional constituents in Brasenia schreberi was isolated from the external mucilage of B. schreberi (BPL-1) and the plant in vivo (BPL-2). This paper examines the relationship between the content of sulfuric radicals and uronic acid in BPL and the antioxidant activity of BPL. Materials and Methods: The free radicals, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+) and 1,1-diphnyl-2-picrylhydrazyl (DPPH-), were used to determine the antioxidant activity of BPL. The Fourier-transform infrared spectroscopy of BPL-1 and BPL-2 revealed typical characteristics of polysaccharides. Results: The two sample types had different contents. This was proved by their different adsorption peak intensities. The IC50 values of BPL-1 (31.189 mg/ml) and BPL-2 (1.863 mg/ml) showed significant DPPH radical scavenging activity. Based on the quantification of ABTS radical scavenging, the IC50 value of BPL-1 (5.460 mg/ml) was higher than that of BPL-2 (0.239 mg/ml). Therefore, in terms of the reducing power, the IC50 value of BPL-1 was too high to determine, and the IC50 value of BPL-2 was found to be 50.557 mg/ml. Hence, the antioxidant activity and total reducing power were high, and they were greater in BPL-2 than in BPL-1. In addition, BPL-2 was found to have more sulfuric radicals and uronic acid than BPL-1. Conclusion: The contents of sulfuric radicals and uronic acid are significantly correlated to the antioxidant activity and reducing power of BPL; the more sulfuric radicals and uronic acid, the more antioxidant activity and reducing power BPL has. SUMMARY The water-soluble crude polysaccharides obtained from the external mucilage and the Brasenia schreberi plant in vivo were confirmed to have high contents of sulfuric radicals and uronic acidBoth BPL-1 and BPL-2 exhibited antioxidative activity and reducing power, and their antioxidative

  9. High-Resolution Electrospray Ionization Mass Spectrometry Analysis of Water- Soluble Organic Aerosols Collected with a Particle into Liquid Sampler

    SciTech Connect

    Bateman, Adam P.; Nizkorodov, Serguei; Laskin, Julia; Laskin, Alexander


    This work demonstrates the utility of a particle-into-liquid sampler (PILS) a technique traditionally used for identification of inorganic ions present in ambient or laboratory aerosols for the analysis of water soluble organic aerosol (OA) using high resolution electrospray ionization mass spectrometry (HR ESI-MS). Secondary organic aerosol (SOA) was produced from 0.5 ppm mixing ratios of limonene and ozone in a 5 m3 Teflon chamber. SOA was collected simultaneously using a traditional filter sampler and a PILS. The filter samples were later extracted with either water or acetonitrile, while the aqueous PILS samples were analyzed directly. In terms of peak intensities, types of detectable compounds, average O:C ratios, and organic mass to organic carbon ratios, the resulting high resolution mass spectra were essentially identical for the PILS and filter based samples. SOA compounds extracted from both filter/acetonitrile extraction and PILS/water extraction accounted for >95% of the total ion current in ESI mass spectra. This similarity was attributed to high solubility of limonene SOA in water. In contrast, significant differences in detected ions and peak abundances were observed for pine needle biomass burning organic aerosol (BBOA) collected with PILS and filter sampling. The water soluble fraction of BBOA is considerably smaller than for SOA, and a number of unique peaks were detectable only by the filter/acetonitrile method. The combination of PILS collection with HR-ESI-MS analysis offers a new approach for molecular analysis of the water-soluble organic fraction in biogenic SOA, aged photochemical smog, and BBOA.

  10. Seasonal cycles of water-soluble organic nitrogen aerosols in a deciduous broadleaf forest in northern Japan

    NASA Astrophysics Data System (ADS)

    Miyazaki, Yuzo; Fu, PingQing; Ono, Kaori; Tachibana, Eri; Kawamura, Kimitaka


    The seasonal variations in aerosol water-soluble organic nitrogen (WSON) concentrations measured in a deciduous forest canopy over an approximately 30 month period were investigated for possible sources in the forest. The WSON concentrations (average 157 ± 127 ng N m-3) and WSON/water-soluble total nitrogen mass fractions (average 20 ± 11%) in the total suspended particulate matter exhibited a clear seasonal cycle with maxima in early summer. The WSON mass was found to reside mostly in the fine-mode size range (Dp < 1.9 µm) during the summer months. WSON was positively correlated with oxidation products of α-pinene and isoprene with similar size distributions, suggesting that secondary formation from biogenic hydrocarbon precursors is a plausible source for WSON in summer. In contrast, the majority of WSON in autumn was associated with coarse fraction (Dp > 1.9 µm), which was similar to the size distributions of sugar compounds, indicating that the major WSON sources in autumn are associated with primary biological emissions. The vertical differences in WSON concentrations suggest that the water-soluble organic aerosol is enriched with nitrogen below the canopy level relative to the forest floor. The WSON concentration increased with enhanced hydrogen ion concentrations in aerosol in the early summer, indicating that aerosol acidity associated with anthropogenic sources outside the forest likely plays an important role in the formation of WSON in that season. The study suggests that multiple sources of WSON within the forest canopy may dominate over others in specific seasons, providing insights into WSON formation processes in forest environments.

  11. Explaining Ionic Liquid Water Solubility in Terms of Cation and Anion Hydrophobicity

    PubMed Central

    Ranke, Johannes; Othman, Alaa; Fan, Ping; Müller, Anja


    The water solubility of salts is ordinarily dictated by lattice energy and ion solvation. However, in the case of low melting salts also known as ionic liquids, lattice energy is immaterial and differences in hydrophobicity largely account for differences in their water solubility. In this contribution, the activity coefficients of ionic liquids in water are split into cation and anion contributions by regression against cation hydrophobicity parameters that are experimentally determined by reversed phase liquid chromatography. In this way, anion hydrophobicity parameters are derived, as well as an equation to estimate water solubilities for cation-anion combinations for which the water solubility has not been measured. Thus, a new pathway to the quantification of aqueous ion solvation is shown, making use of the relative weakness of interactions between ionic liquid ions as compared to their hydrophobicities. PMID:19399248

  12. Preparation, cytotoxicity and in vivo bioimaging of highly luminescent water-soluble silicon quantum dots

    NASA Astrophysics Data System (ADS)

    Fan, Jing-Wun; Vankayala, Raviraj; Chang, Chien-Liang; Chang, Chia-Hua; Chiang, Chi-Shiun; Hwang, Kuo Chu


    Designing various inorganic nanomaterials that are cost effective, water soluble, optically photostable, highly fluorescent and biocompatible for bioimaging applications is a challenging task. Similar to semiconducting quantum dots (QDs), silicon QDs are another alternative and are highly fluorescent, but non-water soluble. Several surface modification strategies were adopted to make them water soluble. However, the photoluminescence of Si QDs was seriously quenched in the aqueous environment. In this report, highly luminescent, water-dispersible, blue- and green-emitting Si QDs were prepared with good photostability. In vitro studies in monocytes reveal that Si QDs exhibit good biocompatibility and excellent distribution throughout the cytoplasm region, along with the significant fraction translocated into the nucleus. The in vivo zebrafish studies also reveal that Si QDs can be evenly distributed in the yolk-sac region. Overall, our results demonstrate the applicability of water-soluble and highly fluorescent Si QDs as excellent in vitro and in vivo bioimaging probes.

  13. Water solubility in aluminous orthopyroxene and the origin of Earth's asthenosphere.


    Mierdel, Katrin; Keppler, Hans; Smyth, Joseph R; Langenhorst, Falko


    Plate tectonics is based on the concept of rigid lithosphere plates sliding on a mechanically weak asthenosphere. Many models assume that the weakness of the asthenosphere is related to the presence of small amounts of hydrous melts. However, the mechanism that may cause melting in the asthenosphere is not well understood. We show that the asthenosphere coincides with a zone where the water solubility in mantle minerals has a pronounced minimum. The minimum is due to a sharp decrease of water solubility in aluminous orthopyroxene with depth, whereas the water solubility in olivine continuously increases with pressure. Melting in the asthenosphere may therefore be related not to volatile enrichment but to a minimum in water solubility, which causes excess water to form a hydrous silicate melt. PMID:17234945

  14. Bidirectional Transformation of a Metamorphic Protein between the Water-Soluble and Transmembrane Native States.


    Tanaka, Koji; Caaveiro, Jose M M; Tsumoto, Kouhei


    The bidirectional transformation of a protein between its native water-soluble and integral transmembrane conformations is demonstrated for FraC, a hemolytic protein of the family of pore-forming toxins. In the presence of biological membranes, the water-soluble conformation of FraC undergoes a remarkable structural reorganization generating cytolytic transmembrane nanopores conducive to cell death. So far, the reverse transformation from the native transmembrane conformation to the native water-soluble conformation has not been reported. We describe the use of detergents with different physicochemical properties to achieve the spontaneous conversion of transmembrane pores of FraC back into the initial water-soluble state. Thermodynamic and kinetic stability data suggest that specific detergents cause an asymmetric change in the energy landscape of the protein, allowing the bidirectional transformation of a membrane protein. PMID:26544760

  15. Delivery of floxuridine derivatives to cancer cells by water-soluble organometallic cages.


    Yi, Jeong Wu; Barry, Nicolas P E; Furrer, Mona A; Zava, Olivier; Dyson, Paul J; Therrien, Bruno; Kim, Byeang Hyean


    The self-assembly of 2,4,6-tris(pyridin-4-yl)-1,3,5-triazine (tpt) triangular panels with p-cymene (pPr(i)C(6)H(4)Me) ruthenium building blocks and 2,5-dioxydo-1,4-benzoquinonato (dobq) or 5,8-dioxydo-1,4-naphthoquinonato (donq) bridges, in the presence of a pyrenyl-nucleoside derivatives (pyreneR), affords the triangular prismatic host-guest compounds [(pyrene-R)⊂Ru(6)(pPr(i)C(6)H(4)Me)(6)(tpt)(2)(dobq)(3)](6+) ([(pyrene-R)⊂1](6+)) and [(pyrene-R)⊂Ru(6)(pPr(i)C(6)H(4)Me)(6)(tpt)(2)(donq)(3)](6+) ([(pyrene-R)⊂2](6+)), respectively. The inclusion of six monosubstitutedpyrenyl-nucleosides (pyrene-R1 = 5'-(1-pyrenyl butanoate)-2'-deoxyuridine, pyrene-R2 = 5-fluoro-5'-(1-pyrenyl butanoate)-2'-deoxyuridine, pyrene-R3 = 5'-{N-[1-oxo-4-(1-pyrenyl)butyl]-glycyl}-2'-deoxyuridine, pyrene-R4 = 5-fluoro-5'-{N-[1-oxo-4-(1-pyrenyl)butyl]-glycyl}-2'-deoxyuridine, pyrene-R5 = 5-fluoro-5'-{N-[1-oxo-4-(1-pyrenyl)butyl]-phenylalanyl}-2'-deoxyvuridine, pyrene-R6 = 5-fluoro-5'-{N-[1-oxo-4-(1-pyrenyl)butyl]-phenylalanyl}-2'-deoxyuridine) has been accomplished. The carceplex nature of [(pyrene-R)⊂1](6+) with the pyrenyl moiety firmly encapsulated in the hydrophobic cavity of the cage with the nucleoside groups pointing outward was confirmed by NMR spectroscopy and electrospray ionization mass spectrometry (ESI-MS), while the host-guest nature of [(pyrene-R)⊂2](6+) was studied in solution by NMR techniques. In contrast to the floxuridine compounds used in the clinic, the host-guest complexes are highly water-soluble. Consequently, the cytotoxicities of these water-soluble compounds have been established using human ovarian A2780 and A2780cisR cancer cells. All the host-guest systems are more cytotoxic than the empty cages alone [1][CF(3)SO(3)](6) (IC(50) = 23 μM) and [2][CF(3)SO(3)](6) (IC(50) = 10 μM), the most active compound [pyrene-R4⊂1][CF(3)SO(3)](6)being 2 orders of magnitude more cytotoxic (IC(50) = 0.3 μM) on these human ovarian cancer cell lines (A2780 and A2780

  16. Selective Organic and Organometallic Reactions in Water-Soluble Host-Guest Supramolecular Systems

    SciTech Connect

    Pluth, Michael D.; Raymond, Kenneth N.; Bergman, Robert G.


    Inspired by the efficiency and selectivity of enzymes, synthetic chemists have designed and prepared a wide range of host molecules that can bind smaller molecules with their cavities; this area has become known as 'supramolecular' or 'host-guest' chemistry. Pioneered by Lehn, Cram, Pedersen, and Breslow, and followed up by a large number of more recent investigators, it has been found that the chemical environment in each assembly - defined by the size, shape, charge, and functional group availability - greatly influences the guest-binding characteristics of these compounds. In contrast to the large number of binding studies that have been carried out in this area, the exploration of chemistry - especially catalytic chemistry - that can take place inside supramolecular host cavities is still in its infancy. For example, until the work described here was carried out, very few examples of organometallic reactivity inside supramolecular hosts were known, especially in water solution. For that reason, our group and the group directed by Kenneth Raymond decided to take advantage of our complementary expertise and attempt to carry out metal-mediated C-H bond activation reactions in water-soluble supramolecular systems. This article begins by providing background from the Raymond group in supramolecular coordination chemistry and the Bergman group in C-H bond activation. It goes on to report the results of our combined efforts in supramolecular C-H activation reactions, followed by extensions of this work into a wider range of intracavity transformations.

  17. Water-soluble polyelectrolyte complexes of Astramol poly(propyleneimine) dendrimers with poly(methacrylate) anion.


    Zhiryakova, Marina V; Izumrudov, Vladimir A


    Water-soluble complexes formed by pyrenyl-tagged poly(methacrylate) anion with cationic DAB-dendr-(NH2)x of five generations, x = 4, 8, 16, 32, and 64 were prepared and studied. The ability of the dendrimers to quench the pyrenyl fluorescence was used to monitor formation/dissociation of the complexes by fluorescence quenching technique. In salt-free solutions, dissociation of the complexes occurred in highly acidic and highly alkaline media independently on the dendrimer generation, whereas stability of the complexes against destruction by added salt (NaCl) enhanced markedly with x increase. Phase separations were dependent on pH and charged ratio of the components, but independent of a dendrimer generation. By contrast, in water-salt solutions the generation had a profound impact on phase diagram manifested by a considerable extension of a heterogeneity region as x increased. These findings strongly suggest that the complexes obey the main regularities ascertained for polyelectrolyte complexes of oppositely charged polyions. The revealed possibility of preparing negatively charged and positively charged complexes with controllable stability and solubility demonstrates potentialities of Astramol dendrimers for design self-assembled and self-adjusted systems attractive for biotechnological and biomedical applications. PMID:25369241

  18. A highly sensitive colorimetric determination of serum zinc using water-soluble pyridylazo dye.


    Makino, T; Saito, M; Horiguchi, D; Kina, K


    A colorimetric method for precise and accurate determination of zinc in serum is presented. Only 0.3 ml of sample is necessary, because of the use of a new, highly sensitive reagent, 2-(5-bromo-2-pyridylazo)-5-(N-n-propyl-N-3-sulfopropylamino)-phenol (epsilon 554nm = 1.3 X 10(5) 1 . mol-1 . cm-1), which is water-soluble and has long-term stability. Interference of iron and copper in serum can be removed by co-precipitation of the iron fluoride complex with trichloroacetic acid precipitated proteins and the copper dithiocarboxy sarcosine complex, respectively. Within-run and day-to-day precision (CV) are in the range of 0.3-3.5% and 1.9-3.1%, respectively, depending on the serum zinc content. A good correlation (r = 0.98, p less than 0.05) was obtained between this method and atomic absorption spectrometry. In contrast to previous colorimetric methods, the present method does not involve heating, extraction with organic solvents, or a cyanide masking system. PMID:7067132

  19. Redispersible fast dissolving nanocomposite microparticles of poorly water-soluble drugs.


    Bhakay, Anagha; Azad, Mohammad; Bilgili, Ecevit; Dave, Rajesh


    Enhanced recovery/dissolution of two wet media-milled, poorly water-soluble drugs, Griseofulvin (GF) and Azodicarbonamide (AZD), incorporated into nanocomposite microparticles (NCMPs) via fluidized bed drying (FBD) and spray-drying (SD) was investigated. The effects of drying method, drug loading, drug aqueous solubility/wettability as well as synergistic stabilization of the milled suspensions on nanoparticle recovery/dissolution were examined. Drug nanoparticle recovery from FBD and SD produced NCMPs having high drug loadings was evaluated upon gentle redispersion via optical microscopy and laser diffraction. During wet-milling, hydroxypropyl cellulose (HPC) alone stabilized more wettable drug (AZD) nanoparticles with slight aggregation, but could not prevent aggregation of the GF nanoparticles. In contrast, well-dispersed, stable nanosuspensions of both drugs were produced when sodium dodecyl sulfate (SDS) and HPC were combined. The FBD and SD NCMPs without SDS exhibited incomplete nanoparticle recovery, causing slower dissolution for GF, but not for AZD, likely due to higher aqueous solubility/wettability of AZD. For high active loaded NCMPs (FBD ∼50 wt%, SD ∼80 wt%) of either drug, HPC-SDS together owing to their synergistic stabilization led to fast redispersibility/dissolution, corroborated via optical microscopy and particle sizing. These positive attributes can help development of smaller, high drug-loaded dosage forms having enhanced bioavailability and better patient compliance. PMID:24333905

  20. The water-soluble extract of Illicium anisatum stimulates mouse vibrissae follicles in organ culture.


    Sakaguchi, Ikuyo; Ishimoto, Hiroko; Matsuo, Masaki; Ikeda, Norikazu; Minamino, Miki; Kato, Yoshiko


    It is well known that reduced blood flow in the scalp is a cause of alopecia. We have shown previously that the extract of Illicium anisatum increases subcutaneous blood flow in mice. In the present study, we used an organ culture system to examine whether this extract promoted hair follicle elongation. B6C3HF1 mouse vibrissae follicles were cultured in serum-free medium for 7 days at 31 degrees C. Follicles treated with water-soluble (WS) extracts of the leaves, fruits and roots of Illicium anisatum or shikimic acid grew significantly longer than controls. In contrast, ethyl acetate-soluble (AS) extracts and n-hexane-soluble (HS) extracts of the leaves, fruits and roots of the plant inhibited hair follicles and shaft growth. Fractionation of the WS fruit extract showed that the number 1 and number 2 fractions possessed hair follicle elongation activity. GC/MS analysis revealed that the number 1 fraction contained shikimic acid, and that the number 2 fraction was a mixture of many components including glycosides and polysaccharides. Reverse transcription-polymerase chain reaction analysis demonstrated that shikimic acid also induced mRNA expression of insulin-like growth factor-1, keratinocyte growth factor, and vascular endothelial growth factor in the hair follicles. These results suggest that the WS extract of Illicium anisatum promotes hair growth and may be a useful additive in hair growth products. PMID:15265014

  1. Application of dry-polishing techniques to water-soluble glass ceramics

    SciTech Connect

    Healey, J.T.; McAllaster, M.E.


    A dry polishing technique is presented for the preparation of glass ceramics for microstructural characterization. The technique is shown to be applicable to water soluble phosphate based glass ceramics and also to a non-water soluble zinc silicate glass ceramic. Microstructural characterization is performed primarily with composition backscattered electron imaging in the scanning electron microscopy. Some relief is observed on the polished surface utilizing topographical backscattered electron imaging.

  2. Synthesis, aggregation and spectroscopic studies of novel water soluble metal free, zinc, copper and magnesium phthalocyanines and investigation of their anti-bacterial properties.


    Bayrak, Rıza; Akçay, Hakkı Türker; Beriş, Fatih Şaban; Sahin, Ertan; Bayrak, Hacer; Demirbaş, Ümit


    In this study, novel phthalonitrile derivative (3) was synthesized by the reaction between 4-nitrophthalonitrile (2) and a triazole derivative (1) containing pyridine moiety. Crystal structure of compound (3) was characterized by X-ray diffraction. New metal free and metallo-phthalocyanine complexes (Zn, Cu, and Mg) were synthesized using the phthalonitrile derivative (3). Cationic derivatives of these phthalocyanines (5, 7, 9, and 11) were prepared from the non-ionic phthalocyanines (4, 6, 8, and 10). All proposed structures were supported by instrumental methods. The aggregation behaviors of the phthalocyanines (4-11) were investigated in different solvents such as dimethylsulfoxide (DMSO), N,N-dimethylformamide (DMF), chloroform and water. Water soluble cationic Pcs (5, 7, 9, and 11) aggregated in water and sodium dodecyl sulfate was used to prevent the aggregation. The second derivatives of the UV-Vis spectra of aggregated Pcs were used for analyzing the Q and B bands of aggregated species. Thermal behaviors of the phthalocyanines were also studied. In addition, anti-bacterial properties of the phthalocyanines were investigated. We used four gram negative and two gram positive bacteria to determine antibacterial activity of these compounds. Compound 7 has the best activity against the all bacteria with 125μg/mL of MIC value. Compounds 4, 6, and 10 have the similar effect on the bacteria with 250μg/mL of MIC value. PMID:24952089

  3. Synthesis, aggregation and spectroscopic studies of novel water soluble metal free, zinc, copper and magnesium phthalocyanines and investigation of their anti-bacterial properties

    NASA Astrophysics Data System (ADS)

    Bayrak, Rıza; Akçay, Hakkı Türker; Beriş, Fatih Şaban; Şahin, Ertan; Bayrak, Hacer; Demirbaş, Ümit


    In this study, novel phthalonitrile derivative (3) was synthesized by the reaction between 4-nitrophthalonitrile (2) and a triazole derivative (1) containing pyridine moiety. Crystal structure of compound (3) was characterized by X-ray diffraction. New metal free and metallo-phthalocyanine complexes (Zn, Cu, and Mg) were synthesized using the phthalonitrile derivative (3). Cationic derivatives of these phthalocyanines (5, 7, 9, and 11) were prepared from the non-ionic phthalocyanines (4, 6, 8, and 10). All proposed structures were supported by instrumental methods. The aggregation behaviors of the phthalocyanines (4-11) were investigated in different solvents such as dimethylsulfoxide (DMSO), N,N-dimethylformamide (DMF), chloroform and water. Water soluble cationic Pcs (5, 7, 9, and 11) aggregated in water and sodium dodecyl sulfate was used to prevent the aggregation. The second derivatives of the UV-Vis spectra of aggregated Pcs were used for analyzing the Q and B bands of aggregated species. Thermal behaviors of the phthalocyanines were also studied. In addition, anti-bacterial properties of the phthalocyanines were investigated. We used four gram negative and two gram positive bacteria to determine antibacterial activity of these compounds. Compound 7 has the best activity against the all bacteria with 125 μg/mL of MIC value. Compounds 4, 6, and 10 have the similar effect on the bacteria with 250 μg/mL of MIC value.

  4. Impact of biochar amendment on soil water soluble carbon in the context of extreme hydrological events.


    Wang, Daoyuan; Griffin, Deirdre E; Parikh, Sanjai J; Scow, Kate M


    Biochar amendments to soil have been promoted as a low cost carbon (C) sequestration strategy as well as a way to increase nutrient retention and remediate contaminants. If biochar is to become part of a long-term management strategy, it is important to consider its positive and negative impacts, and their trade-offs, on soil organic matter (SOM) and soluble C under different hydrological conditions such as prolonged drought or frequent wet-dry cycles. A 52-week incubation experiment measuring the influence of biochar on soil water soluble C under different soil moisture conditions (wet, dry, or wet-dry cycles) indicated that, in general, dry and wet-dry cycles increased water soluble C, and biochar addition further increased release of water soluble C from native SOM. Biochar amendment appeared to increase transformation of native SOM to water soluble C, based on specific ultraviolet absorption (SUVA) and C stable isotope composition; however, the increased amount of water soluble C from native SOM is less than 1% of total biochar C. The impacts of biochar on water soluble C need to be carefully considered when applying biochar to agricultural soil. PMID:27391051

  5. Water-soluble organic carbon, dicarboxylic acids, ketoacids, and α-dicarbonyls in the tropical Indian aerosols

    NASA Astrophysics Data System (ADS)

    Pavuluri, Chandra Mouli; Kawamura, Kimitaka; Swaminathan, T.


    Tropical aerosol (PM10) samples (n = 49) collected from southeast coast of India were studied for water-soluble dicarboxylic acids (C2-C12), ketocarboxylic acids (C2-C9), and α-dicarbonyls (glyoxal and methylglyoxal), together with analyses of total carbon (TC) and water-soluble organic carbon (WSOC). Their distributions were characterized by a predominance of oxalic acid followed by terephthalic (t-Ph), malonic, and succinic acids. Total concentrations of diacids (227-1030 ng m-3), ketoacids (16-105 ng m-3), and dicarbonyls (4-23 ng m-3) are comparative to those from other Asian megacities such as Tokyo and Hong Kong. t-Ph acid was found as the second most abundant diacid in the Chennai aerosols. This feature has not been reported previously in atmospheric aerosols. t-Ph acid is most likely derived from the field burning of plastics. Water-soluble diacids were found to contribute 0.4%-3% of TC and 4%-11% of WSOC. Based on molecular distributions and backward air mass trajectories, we found that diacids and related compounds in coastal South Indian aerosols are influenced by South Asian and Indian Ocean monsoons. Organic aerosols are also suggested to be significantly transported long distances from North India and the Middle East in early winter and from Southeast Asia in late winter, but some originate from photochemical reactions over the Bay of Bengal. In contrast, the Arabian Sea, Indian Ocean, and South Indian continent are suggested as major source regions in summer. We also found daytime maxima of most diacids, except for C9 and t-Ph acids, which showed nighttime maxima in summer. Emissions from marine and terrestrial plants, combined with land/sea breezes and in situ photochemical oxidation, are suggested especially in summer as an important factor that controls the composition of water-soluble organic aerosols over the southeast coast of India. Regional emissions from anthropogenic sources are also important in megacity Chennai, but their influence is

  6. Enhanced Glutathione Peroxidase Activity of Water-Soluble and Polyethylene Glycol-Supported Selenides, Related Spirodioxyselenuranes, and Pincer Selenuranes.


    McNeil, Nicole M R; Press, David J; Mayder, Don M; Garnica, Pablo; Doyle, Lisa M; Back, Thomas G


    Diaryl selenides containing o-hydroxymethylene substituents function as peroxide-destroying mimetics of the antioxidant selenoenzyme glutathione peroxidase (GPx), via oxidation to the corresponding spirodioxyselenuranes with hydrogen peroxide and subsequent reduction back to the original selenides with glutathione. Parent selenides with 3-hydroxypropyl or 2,3-dihydroxypropyl groups produced the novel compounds 10 and 11, respectively, with greatly improved aqueous solubility and catalytic activity. The phenolic derivative 28 displayed similarly ameliorated properties and also modest radical-inhibiting antioxidant activity, as evidenced by an assay based on phenolic hydrogen atom transfer to the stable free radical DPPH. In contrast, several selenides that afford pincer selenuranes (e.g., 20 and 21) instead of spiroselenuranes upon oxidation showed inferior catalytic activity. Several selenide analogues were attached to polyethylene glycol (PEG) oligomers, as PEG substituents can improve water solubility and bioavailability, while retarding clearance. Again, the PEG derivatives afforded remarkable activity when oxidation generated spirodioxyselenuranes and diminished activity when pincer compounds were produced. Several such compounds proved to be ca. 10- to 100-fold catalytically superior to the diaryl selenides and their spirodioxyselenurane counterparts investigated previously. Finally, an NMR-based assay employing glutathione in D2O was designed to accommodate the faster reacting water-soluble mimetics and to more closely duplicate in vivo conditions. PMID:27525346

  7. Antibacterial effect of water-soluble chitosan on representative dental pathogens Streptococcus mutans and Lactobacilli brevis

    PubMed Central

    CHEN, Chih-YU; CHUNG, Ying-CHIEN


    Dental caries is still a major oral health problem in most industrialized countries. The development of dental caries primarily involves Lactobacilli spp. and Streptococcus mutans. Although antibacterial ingredients are used against oral bacteria to reduce dental caries, some reports that show partial antibacterial ingredients could result in side effects. Objectives The main objective is to test the antibacterial effect of water-soluble chitosan while the evaluation of the mouthwash appears as a secondary aim. Material and Methods The chitosan was obtained from the Application Chemistry Company (Taiwan). The authors investigated the antibacterial effects of water-soluble chitosan against oral bacteria at different temperatures (25-37ºC) and pH values (pH 5-8), and evaluated the antibacterial activities of a self-made water-soluble chitosan-containing mouthwash by in vitro and in vivo experiments, and analyzed the acute toxicity of the mouthwashes. The acute toxicity was analyzed with the pollen tube growth (PTG) test. The growth inhibition values against the logarithmic scale of the test concentrations produced a concentrationresponse curve. The IC50 value was calculated by interpolation from the data. Results The effect of the pH variation (5-8) on the antibacterial activity of water-soluble chitosan against tested oral bacteria was not significant. The maximal antibacterial activity of water-soluble chitosan occurred at 37ºC. The minimum bactericidal concentration (MBC) of water-soluble chitosan on Streptococcus mutans and Lactobacilli brevis were 400 µg/mL and 500 µg/mL, respectively. Only 5 s of contact between water-soluble chitosan and oral bacteria attained at least 99.60% antibacterial activity at a concentration of 500 µg/mL. The water-soluble chitosan-containin g mouthwash significantly demonstrated antibacterial activity that was similar to that of commercial mouthwashes (>99.91%) in both in vitro and in vivo experiments. In addition, the alcohol

  8. Comparison of the performance of non-ionic and anionic surfactants as mobile phase additives in the RPLC analysis of basic drugs.


    Ruiz-Ángel, María J; García-Álvarez-Coque, María C


    Surfactants added to the mobile phases in reversed-phase liquid chromatography (RPLC) give rise to a modified stationary phase, due to the adsorption of surfactant monomers. Depending on the surfactant nature (ionic or non-ionic), the coated stationary phase can exhibit a positive net charge, or just change its polarity remaining neutral. Also, micelles in the mobile phase introduce new sites for solute interaction. This affects the chromatographic behavior, especially in the case of basic compounds. Two surfactants of different nature, the non-ionic Brij-35 and the anionic sodium dodecyl sulfate (SDS) added to water or aqueous-organic mixtures, are here compared in the separation of basic compounds (β-blockers and tricyclic antidepressants). The reversible/irreversible adsorption of the monomers of both surfactants on the stationary phase was examined. The changes in the nature of the chromatographic system using different columns and chromatographic conditions were followed based on the changes in retention and peak shape. The study revealed that Brij-35 is suitable for analyzing basic compounds of intermediate polarity, using "green chemistry", since the addition of an organic solvent is not needed and Brij-35 is a biodegradable surfactant. In contrast, RPLC with hydro-organic mixtures or mobile phases containing SDS required high concentrations of organic solvents. PMID:21328695

  9. Colloidal behavior of aqueous montmorillonite suspensions in the presence of non-ionic polymer

    NASA Astrophysics Data System (ADS)

    Gareche, M.; Azri, N.; Allal, A.; Zeraibi, N.


    In this paper we characterized at first, the rheological behavior of the bentonite suspensions and the aqueous solutions of polyethylene oxide (PEO), then we were investigated the influence of this polymer in a water-based drilling fluid model (6% of bentonite suspension). The objective is to exhibit how the non ionic polymer with molecular weight 6×103 g/mol. of varying concentration mass (0.7%, 1%, 2% et 3%) significantly alter the rheological properties (yield stress, viscosity, loss and elastic modulus) of the bentonite suspensions. The rheological measurements made in simple shear and in dynamic on the mixture (water-bentonite-PEO), showed rheological properties of bentonite suspensions both in the presence and absence of non-ionic polymer. The PEO presents an affinity for the bentonite particles slowing down their kinetic aggregation. The analysis by X-rays diffraction also allowed understanding the structure of this mixture. It had revealed the intercalation between of the clay platelets on one hand, and the links bridges assured by the chains of polymer between bentonite particles beyond a critical concentration in PEO on the other hand. The Herschel- Bulkley rheological model is used for the correlation of our experimental results.

  10. Stabilization of urinary THC solutions with a simple non-ionic surfactant.


    Welsh, Eric R; Snyder, J Jacob; Klette, Kevin L


    To stabilize urinary solutions against adsorptive loss of metabolites of Delta9-tetrahydrocannabinol (THC), a non-ionic surfactant, Tergitol, was investigated to reduce the need for special handling and storage of such solutions. Addition of surfactant up to 20 times the critical micelle concentration (CMC) did not adversely affect the analytical process. Yet, at only two times CMC, surfactant was found to mitigate adsorptive loss of THC analytes under a variety of storage and handling conditions including exposure to glass and plastic surfaces, after storage in a refrigerator or freezer, and at reduced pH, where adsorptive losses were expected to be significant. On average, micellar solubilization of analyte increased the assayed concentration by 10% with a range of 3 to 20%, depending on condition, relative to solutions without surfactant. Solutions with surfactant did not fail (i.e., deviate in concentration by +/-20%) over a 49-week period, whereas those without surfactant failed by 21 weeks. These results indicate that addition of small amounts of non-ionic surfactant to solutions of urinary THC metabolites is a simple method to improve both the accuracy and precision of analyte concentrations, as determined by gas chromatography-mass spectrometry, in such solutions by mitigating adsorptive losses during storage and handling events. PMID:19161669

  11. Ternary phase diagrams of a thermoreversible chelating non-ionic surfactant.


    Nave, S; Testard, F; Coulombeau, H; Baczko, K; Larpent, C; Zemb, Th


    The behaviour of a di-block molecule associating a diamide group and a non-ionic surfactant (C(i)E(j)) is determined in a ternary surfactant/water/oil/system. Its properties are compared to the ones of a parent non-ionic surfactant C(i)E(j) through the limits of boundaries in the phase prisms. The existence of a stable microemulsion single phase in a defined temperature and concentration range is demonstrated. The extension of the microemulsion domain is limited by the presence of a gel, containing lyotropic liquid crystals as gelling agents. Temperature dependence is observed for the curvature below the temperature of zero spontaneous curvature, but the ternary system cannot produce reverse microemulsion as observed with classical C(i)E(j). The decrease of the mean curvature with temperature is inhibited by the presence of the diamide as a grafted complexing group. Liquid-liquid extraction processes with this type of surfactant are possible, but will require the presence of at least a fourth component to enlarge the water in an oil microemulsion domain. PMID:19421528

  12. Effect of photochemical pre-treatment on COD fractionation of a non-ionic textile surfactant.


    Cokgor, E U; Arsian-Alaton, I; Erdinc, E; Insel, G; Orhon, D


    The work presented in this paper is focused on the effect of photochemical (H2O2/UV-C) pretreatment on COD fractionation and degradation kinetics of a non-ionic textile surfactant. In the first part of the study, the COD of non-ionic surfactant was adjusted to 1000 mg/L in order to simulate real effluent originating from the textile preparation stage featuring desizing, scouring, washing and rinsing operations. The surfactant was subjected to H2O2/UV-C pretreatment for up to 120 min at a dose of 30 mM (980 mg/L) H2O2. The biodegradability studies for untreated and photochemically treated samples were evaluated on the basis of modeling of oxygen uptake rate (OUR) profiles. Modelling of OUR profiles conducted for untreated sample showed that single complex substrate was subjected to enzymatic breakdown and disintegrated into one readily and two types of slowly biodegradable substrates. After modelling the biodegradation of photochemically pretreated sample, the readily biodegradable COD fraction was reduced, on the other hand, more slowly biodegradable organics were generated. A higher disintegration rate was obtained for chemically pretreated samples. However, other kinetic constants of growth and hydrolysis processes were not affected considerably. PMID:17564381

  13. Fabrication and Mechanical Characterization of Water-Soluble Resin-Coated Natural Fiber Green Composites

    NASA Astrophysics Data System (ADS)

    Manabe, Ken-Ichi; Hayakawa, Tomoyuki

    In this study, water-soluble biodegradable resin was introduced as a coating agent to improve the interfacial strength and then to fabricate a high-performance green composite with polylactic acid (PLA) and hemp yarn. Dip coating was carried out for hemp yarn and the green composites were fabricated by hot processing. The coated green composite achieves a high tensile strength of 117 MPa even though the fiber volume fraction is less than 30%. Interfacial shear strength (IFSS) was measured by a single fiber pull-out test, and the effect of water-soluble resin on the tensile properties of the composites was evaluated. As a result, when using coated natural bundles, the IFSS value is smaller than when using noncoated natural bundles. On the basis of observations of the fractured surface of composites and initial yarns using a scanning electron microscope (SEM), the effect of the impregnation of water-soluble resin into the natural bundles on the tensile strength is discussed in detail. It is found that water-soluble resin is effective in improving the mechanical properties of the composite, although the interfacial strength between PLA and water-soluble resin was decreased, and as a result, the tensile strength of green composites increases by almost 20%.

  14. Study on Mixed Solvency Concept in Formulation Development of Aqueous Injection of Poorly Water Soluble Drug

    PubMed Central

    Solanki, Shailendra Singh; Soni, Love Kumar; Maheshwari, Rajesh Kumar


    In the present investigation, mixed-solvency approach has been applied for the enhancement of aqueous solubility of a poorly water- soluble drug, zaltoprofen (selected as a model drug), by making blends (keeping total concentrations 40% w/v, constant) of selected water-soluble substances from among the hydrotropes (urea, sodium benzoate, sodium citrate, nicotinamide); water-soluble solids (PEG-4000, PEG-6000); and co-solvents (propylene glycol, glycerine, PEG-200, PEG-400, PEG-600). Aqueous solubility of drug in case of selected blends (12 blends) ranged from 9.091 ± 0.011 mg/ml–43.055 ± 0.14 mg/ml (as compared to the solubility in distilled water 0.072 ± 0.012 mg/ml). The enhancement in the solubility of drug in a mixed solvent containing 10% sodium citrate, 5% sodium benzoate and 25 % S cosolvent (25% S cosolvent contains PEG200, PEG 400, PEG600, Glycerine and Propylene glycol) was more than 600 fold. This proved a synergistic enhancement in solubility of a poorly water-soluble drug due to mixed cosolvent effect. Each solubilized product was characterized by ultraviolet and infrared techniques. Various properties of solution such as pH, viscosity, specific gravity and surface tension were studied. The developed formulation was studied for physical and chemical stability. This mixed solvency shall prove definitely a boon for pharmaceutical industries for the development of dosage form of poorly water soluble drugs. PMID:26555989

  15. Effects of PAH biodegradation in the presence of non-ionic surfactants on a bacterial community and its exoenzymatic activity.


    Chang, Yi-Tang; Thirumavalavan, Munusamy; Lee, Jiunn-Fwu


    The influence of two non-ionic surfactants (TX-100 and Brij 35) on a bacterial community and its exoenzymatic activity during polycyclic aromatic hydrocarbon (naphthalene, phenanthrene and pyrene) biodegradation was evaluated in this study. The result indicated the addition of the non-ionic surfactants altered the profiles of the microbial populations and produced exoenzymes. Fluorescence in situ hybridization found that, as PAH biodegradation progressed in the presence of non-ionic surfactant, the proportion of Bacteria presents increased significantly from the range 54.79%-57.00% to 64.17%-73.4% and there was parallel decrease in Archaea. The trends in five phyla/subclass of Bacteria, namely alpha -, beta -, or gamma -Proteobacteria, HGC bacteria and LGC bacteria, were influenced significantly by the addition of Brij 35 as either monomers or micelles. A change was ascribed to different cohesive energy density (CED) value between the PAH and surfactant. The percentage of genera Pseudomonas 4.76%-12.67%, which included two signals, namely most true Pseudomonas spp. and Pseudomonas aeruginosa, were dominant during biodegradation. For exoenzymaztic activities, trends were identified by principle component analysis of the API ZYM enzymatic activity dataset. The additions of non-ionic surfactant were identified strong activities of three esterase (esterase, esterase lipase and lipase), alpha -glucosidase, beta -glucosidase, leucine arylamidase and acid phosphatase during PAH biodegradation. These enzymes are selected as possible organic pollutant indicators when the in situ bioremediation was monitored in the presence of non-ionic surfactant additives. PMID:20390887

  16. Injectable polyanhydride granules provide controlled release of water-soluble drugs with a reduced initial burst.


    Tabata, Y; Domb, A; Langer, R


    A method for preparing polyanhydride granules of an injectable size was developed. The resulting granules permitted a nearly constant release of low-molecular-weight, water-soluble drugs without an initial burst. The polyanhydrides used were poly(fatty acid dimer), poly(sebacic acid), and their copolymers. The dyes acid orange 63 and p-nitroaniline were used as model compounds for drugs. Polymer degradation and drug release for disks and variously sized granules of copolymers containing drugs, prepared by a water-in-oil (W/O) emulsion method, were compared with those for devices prepared by the usual compression method. In the W/O emulsion method, a mixture of aqueous drug solution and polymer-chloroform solution was emulsified by probe sonication to prepare a very fine W/O emulsion. The powder obtained by freeze-drying of the W/O emulsion was pressed into circular disks. In the compression method, the drug was mechanically mixed with the polymer, and the mixture was compressed into circular disks. The resulting disks were ground to prepare granules of different sizes. The granules encapsulated more than 95% of the drug, irrespective of the preparation method. Both methods were effective in preparing polymer disks capable of controlled drug release without any initial burst. However, as the granule size decreased to an injectable size (diameter, < 150 microns), a large difference in the drug release profile was observed between the two preparation methods. The injectable granules obtained by the W/O emulsion method showed nearly constant drug release without any large initial burst, in contrast to those prepared by the compression method, irrespective of the drug type.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8138910

  17. Synthesis of water-soluble silicon-porphyrin: protolytic behaviour of axially coordinated hydroxy groups.


    Remello, Sebastian Nybin; Kuttassery, Fazalurahman; Hirano, Takehiro; Nabetani, Yu; Yamamoto, Daisuke; Onuki, Satomi; Tachibana, Hiroshi; Inoue, Haruo


    A new water-soluble silicon(IV)-tetra(4-carboxyphenyl)porphyrin (SiTCPP) with silicon(iv), the second most abundant element on Earth, in the center of porphyrin was synthesized. Fundamental properties including protolytic behaviour of axially coordinating hydroxy groups, and electrochemical behaviour were characterized. The properties were compared with those of silicon(IV)-tetra(2,4,6-trimethylphenyl)porphyrin (SiTMP) and silicon(IV)-tetra(4-trifluoromethylphenyl)porphyrin (SiTFMPP) and discussed in respect to the electron donating/withdrawing effect of the substituents. Two axially coordinating hydroxy groups of SiTCPP exhibit a four-step protolytic behaviour under the acidic conditions along with a single step protolysis of peripheral carboxyl groups. Though SiTCPP and SiTFMPP did not show any reactivity in the photochemical oxygenation of a substrate with K2PtCl6 as a sacrificial electron acceptor, the first oxidation wave in the electrochemical process of SiTCPP and SiTFMPP showed catalytic behaviour in aqueous acetonitrile solution at any pH condition, in contrast to SiTMP which has only a reversible oxidation wave under neutral and weakly acidic conditions. The criteria for the electrochemical oxidative activation of water and the photooxygenation of the substrate were obtained. The higher oxidation wave of Si-porphyrins than ∼0.86 volt vs. SHE is required for the electrochemical oxidation of water, while suitable protecting groups such as a methyl substituent is a requisite for the photochemical oxygenation with K2PtCl6 as a sacrificial electron acceptor. PMID:26526697

  18. Effect of supplementation of water-soluble vitamins on oxidative stress and blood pressure in prehypertensives.


    Talikoti, Prashanth; Bobby, Zachariah; Hamide, Abdoul


    The objective of the study was to evaluate the effect of water-soluble vitamins on oxidative stress and blood pressure in prehypertensives. Sixty prehypertensives were recruited and randomized into 2 groups of 30 each. One group received water-soluble vitamins and the other placebo for 4 months. Further increase in blood pressure was not observed in the vitamin group which increased significantly in the placebo group at the end of 4 months. Malonedialdehyde and protein carbonylation were reduced during the course of treatment with vitamins whereas in the placebo group there was an increase in the level of malondialdehyde. In conclusion, supplementation of water-soluble vitamins in prehypertension reduces oxidative stress and its progression to hypertension. PMID:25588130

  19. Coaxial electrospinning for encapsulation and controlled release of fragile water-soluble bioactive agents.


    Jiang, Hongliang; Wang, Liqun; Zhu, Kangjie


    Coaxial electrospinning is a robust technique for one-step encapsulation of fragile, water-soluble bioactive agents, including growth factors, DNA and even living organisms, into core-shell nanofibers. The coaxial electrospinning process eliminates the damaging effects due to direct contact of the agents with organic solvents or harsh conditions during emulsification. The shell layer serves as a barrier to prevent the premature release of the water-soluble core contents. By varying the structure and composition of the nanofibers, it is possible to precisely modulate the release of the encapsulated agents. Promising work has been done with coaxially electrospun non-woven mats integrated with bioactive agents for use in tissue engineering, in local delivery and in wound healing, etc. This paper reviews the origins of the coaxial electrospinning method, its updated status and potential future developments for controlled release of the class of fragile, water-soluble bioactive agents. PMID:24780265

  20. Effect of addition of water-soluble chitin on amylose film.


    Suzuki, Shiho; Shimahashi, Katsumasa; Takahara, Junichi; Sunako, Michihiro; Takaha, Takeshi; Ogawa, Kozo; Kitamura, Shinichi


    Amylose films blended with chitosan, which were free from additives such as acid, salt, and plasticizer, were prepared by casting mixtures of an aqueous solution of an enzymatically synthesized amylose and that of water-soluble chitin (44.1% deacetylated). The presence of a small amount of chitin (less than 10%) increased significantly the permeability of gases (N2, O2, CO2, C2H4) and improved the mechanical parameters of amylose film; particularly, the elastic modulus and elongation of the blend films were larger than those of amylose or chitin films. No antibacterial activity was observed with either amylose or water-soluble chitin films. But amylose films having a small amount of chitin showed strong antibacterial action, suggesting a morphological change in water-soluble chitin on the film surface by blending with amylose molecule. These facts suggested the presence of a molecular complex of amylose and chitosan. PMID:16283751

  1. Synthesis, characterization and fluorescent properties of water-soluble glycopolymer bearing curcumin pendant residues.


    Zhang, Haisong; Yu, Meng; Zhang, Hailei; Bai, Libin; Wu, Yonggang; Wang, Sujuan; Ba, Xinwu


    Curcumin is a potential natural anticancer drug with low oral bioavailability because of poor water solubility. The aqueous solubility of curcumin is enhanced by means of modification with the carbohydrate units. Polymerization of the curcumin-containing monomer with carbohydrate-containing monomer gives the water-soluble glycopolymer bearing curcumin pendant residues. The obtained copolymers (P1 and P2) having desirable water solubility were well-characterized by infrared spectroscopy (IR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), UV-Vis absorption spectroscopy, and photoluminescence spectroscopy. The copolymer P2 with a molar ratio of 1:6 (curcumin/carbohydrate) calculated from the proton NMR results exhibits a similar anticancer activity compared to original curcumin, which may serve as a potential chemotherapeutic agent in the field of anticancer medicine. PMID:27098211

  2. [New conjugates of antitumor antibiotic doxorubicin with water-soluble galactomannan: synthesis and biological activity].


    Teviashova, A N; Olsuf'eva, E N; Preobrazhenskaia, M N; Klesov, A A; Zomer, E; Platt, D


    New water-soluble conjugates in the form of Schiff bases (DGM-1 and DGM-2) were prepared by the interaction of water-soluble periodate-oxidized galactomannan with doxorubicin or N-(L-lysyl)doxorubicin, respectively. The water-soluble galactomannan (DAVANAT a commercial product of Pro-Pharmaceuticals company) was obtained by partial acidic hydrolysis of high-molecular-mass galactomannan from Cyamopsis tetragonoloba (guar gum) seeds. The conjugate stability was studied in aqueous solutions. The DGM-1 antiproliferative activity was comparable with that of doxorubicin on three models: cell lines of murine melanoma B 16-F1, human breast cancer MCF-7 (HTB-22), and human colon cancer HT-29 (HTB-38). DGM-2 was poorly active in all the three tests. DGM- 1 can thus be regarded as a high-molecular-mass depot form of doxorubicin. PMID:17375669

  3. Intestinal absorption of water-soluble vitamins in health and disease

    PubMed Central

    Said, Hamid M.


    Our knowledge of the mechanisms and regulation of intestinal absorption of water-soluble vitamins under normal physiological conditions, and of the factors/conditions that affect and interfere with theses processes has been significantly expanded in recent years as a result of the availability of a host of valuable molecular/cellular tools. Although structurally and functionally unrelated, the water-soluble vitamins share the feature of being essential for normal cellular functions, growth and development, and that their deficiency leads to a variety of clinical abnormalities that range from anaemia to growth retardation and neurological disorders. Humans cannot synthesize water-soluble vitamins (with the exception of some endogenous synthesis of niacin) and must obtain these micronutrients from exogenous sources. Thus body homoeostasis of these micronutrients depends on their normal absorption in the intestine. Interference with absorption, which occurs in a variety of conditions (e.g. congenital defects in the digestive or absorptive system, intestinal disease/resection, drug interaction and chronic alcohol use), leads to the development of deficiency (and sub-optimal status) and results in clinical abnormalities. It is well established now that intestinal absorption of the water-soluble vitamins ascorbate, biotin, folate, niacin, pantothenic acid, pyridoxine, riboflavin and thiamin is via specific carrier-mediated processes. These processes are regulated by a variety of factors and conditions, and the regulation involves transcriptional and/or post-transcriptional mechanisms. Also well recognized now is the fact that the large intestine possesses specific and efficient uptake systems to absorb a number of water-soluble vitamins that are synthesized by the normal microflora. This source may contribute to total body vitamin nutrition, and especially towards the cellular nutrition and health of the local colonocytes. The present review aims to outline our current

  4. Surfactant-assisted synthesis of water-soluble and biocompatible semiconductor quantum dot-micelles.

    SciTech Connect

    Brinker, C. Jeffrey; Bunge, Scott D.; Gabaldon, John; Fan, Hongyou; Scullin, Chessa; Leve, Erik W.; Wilson, Michael C.; Tallant, David Robert; Boyle, Timothy J.


    We report a simple, rapid approach to synthesize water-soluble and biocompatible fluorescent quantum dot (QD) micelles by encapsulation of monodisperse, hydrophobic QDs within surfactant/lipid micelles. Analyses of UV-vis and photo luminescence spectra, along with transmission electron microscopy, indicate that the water-soluble semiconductor QD micelles are monodisperse and retain the optical properties of the original hydrophobic QDs. The QD micelles were shown to be biocompatible and exhibited little or no aggregation when taken up by cultured rat hippocampal neurons.

  5. Cryptic clues as to how water-soluble protein toxins form pores in membranes.


    Parker, Michael W


    Pore-forming protein toxins possess the remarkable property that they can exist either in a stable water-soluble state or as an integral membrane pore. In order to convert from the water-soluble to the membrane state, the toxin must undergo large conformational changes. Recent work on a class of pore-forming toxins that are rich in beta-sheet content suggests a common mechanism of membrane insertion may exist despite these toxins possessing very different primary, tertiary and quaternary structures. PMID:12893054

  6. Method of immobilizing water-soluble bioorganic compounds on a capillary-porous carrier


    Ershov, Gennady Moiseevich; Timofeev, Eduard Nikolaevich; Ivanov, Igor Borisovich; Florentiev, Vladimir Leonidovich; Mirzabekov, Andrei Darievich


    The method for immobilizing water-soluble bioorganic compounds to capillary-porous carrier comprises application of solutions of water-soluble bioorganic compounds onto a capillary-porous carrier, setting the carrier temperature equal to or below the dew point of the ambient air, keeping the carrier till appearance of water condensate and complete swelling of the carrier, whereupon the carrier surface is coated with a layer of water-immiscible nonluminescent inert oil and is allowed to stand till completion of the chemical reaction of bonding the bioorganic compounds with the carrier.

  7. Determination of water-soluble ions in soils from the dry valleys of Antarctica

    NASA Technical Reports Server (NTRS)

    Bustin, R.


    The soil chemistry of the dry valleys of Antarctica was studied. These valleys furnish a terrestrial analog for the surface of Mars. The abundance of the water-soluble ions magnesium, calcium, potassium, sodium chloride, and nitrate in soil samples was determined. All samples examined contained water-soluble salts reflecting the aridity of the area. Movement of salts to low-lying areas was verified. Upward ionic migration was evident in all core samples. Of all cations observed, sodium showed the greatest degree of migration.

  8. Characteristics of size-fractionated atmospheric metals and water-soluble metals in two typical episodes in Beijing

    NASA Astrophysics Data System (ADS)

    Wang, Qingqing; Ma, Yongliang; Tan, Jihua; Zheng, Naijia; Duan, Jingchun; Sun, Yele; He, Kebin; Zhang, Yuanxun


    The abundance and behaviour of metals and water-soluble metals (V, Cr, Mn, Fe, Cu, Zn, As, Sr, Ag, Cd, Sn, Sb, Ba and Pb) in size-fractionated aerosols were investigated during two typical episodes in Beijing. Water-soluble inorganic ions (Na+, K+, Mg2+, Ca2+, NH4+ , F-, Cl-, SO4 2 - and NO3-) were also measured. Atmospheric metals and water-soluble metals were both found at high levels; for PM2.5, average As, Cr, Cd, Cu, Mn and Pb concentrations were 14.8, 203.3, 2.5, 18.5, 42.6 and 135.3 ng/m3, respectively, and their water-soluble components were 11.1, 1.7, 2.4, 14.5, 19.8 and 97.8 ng/m3, respectively. Daily concentrations of atmospheric metals and water-soluble metals were generally in accordance with particle mass. The highest concentrations of metals and water-soluble metals were generally located in coarse mode and droplet mode, respectively. The lowest mass of metals and water-soluble metals was mostly in Aitken mode. The water solubility of all metals was low in Aitken and coarse modes, indicating that freshly emitted metals have low solubility. Metal water solubility generally increased with the decrease in particle size in the range of 0.26-10 μm. The water solubility of metals for PM10 was: 50% ≤ Cd, As, Sb, Pb; 26% < V, Mn, Cu, Zn and Sr ≤ 50%; others ≤20%. Most metals, water-soluble metals and their water solubility increased when polluted air mass came from the near west, near north-west, south-west and south-east of the mainland, and decreased when clean air mass came from the far north-west and far due south. The influence of dust-storms and clean days on water-soluble metals and size distribution was significant; however, the influence of rainfall was negligible. Aerosols with high concentrations of SO4 2 - , K+ and NH4+ might indicate increased potential for human health effects because of their high correlation with water-soluble metals. Industrial emissions contribute substantially to water-soluble metal pollution as water-soluble metals

  9. Characteristics of size-fractionated atmospheric metals and water-soluble metals in two typical episodes in Beijing

    NASA Astrophysics Data System (ADS)

    Wang, Qingqing; Ma, Yongliang; Tan, Jihua; Zheng, Naijia; Duan, Jingchun; Sun, Yele; He, Kebin; Zhang, Yuanxun


    The abundance and behaviour of metals and water-soluble metals (V, Cr, Mn, Fe, Cu, Zn, As, Sr, Ag, Cd, Sn, Sb, Ba and Pb) in size-fractionated aerosols were investigated during two typical episodes in Beijing. Water-soluble inorganic ions (Na+, K+, Mg2+, Ca2+, NH4+ , F-, Cl-, SO42- and NO3-) were also measured. Atmospheric metals and water-soluble metals were both found at high levels; for PM2.5, average As, Cr, Cd, Cu, Mn and Pb concentrations were 14.8, 203.3, 2.5, 18.5, 42.6 and 135.3 ng/m3, respectively, and their water-soluble components were 11.1, 1.7, 2.4, 14.5, 19.8 and 97.8 ng/m3, respectively. Daily concentrations of atmospheric metals and water-soluble metals were generally in accordance with particle mass. The highest concentrations of metals and water-soluble metals were generally located in coarse mode and droplet mode, respectively. The lowest mass of metals and water-soluble metals was mostly in Aitken mode. The water solubility of all metals was low in Aitken and coarse modes, indicating that freshly emitted metals have low solubility. Metal water solubility generally increased with the decrease in particle size in the range of 0.26-10 μm. The water solubility of metals for PM10 was: 50% ≤ Cd, As, Sb, Pb; 26% < V, Mn, Cu, Zn and Sr ≤ 50%; others ≤20%. Most metals, water-soluble metals and their water solubility increased when polluted air mass came from the near west, near north-west, south-west and south-east of the mainland, and decreased when clean air mass came from the far north-west and far due south. The influence of dust-storms and clean days on water-soluble metals and size distribution was significant; however, the influence of rainfall was negligible. Aerosols with high concentrations of SO42- , K+ and NH4+ might indicate increased potential for human health effects because of their high correlation with water-soluble metals. Industrial emissions contribute substantially to water-soluble metal pollution as water-soluble metals

  10. Aqueous cationic, anionic and non-ionic multi-walled carbon nanotubes, functionalised with minimal framework damage, for biomedical application

    PubMed Central

    Chen, Shu; Hu, Sheng; Smith, Elizabeth F.; Ruenraroengsak, Pakatip; Thorley, Andrew J.; Menzel, Robert; Goode, Angela E.; Ryan, Mary P.; Tetley, Teresa D.; Porter, Alexandra E.; Shaffer, Milo S. P.


    The use of a thermochemical grafting approach provides a versatile means to functionalise as-synthesised, bulk multi-walled carbon nanotubes (MWNTs) without altering their inherent structure. The associated retention of properties is desirable for a wide range of commercial applications, including for drug delivery and medical purposes; it is also pertinent to studies of intrinsic toxicology. A systematic series of water-compatible MWNTs, with diameter around 12 nm have been prepared, to provide structurally-equivalent samples predominantly stabilised by anionic, cationic, or non-ionic groups. The surface charge of MWNTs was controlled by varying the grafting reagents and subsequent post-functionalisation modifications. The degree of grafting was established by thermal analysis (TGA). High resolution transmission electron microscope (HRTEM) and Raman measurements confirmed that the structural framework of the MWNTs was unaffected by the thermochemical treatment, in contrast to a conventional acid-oxidised control which was severely damaged. The effectiveness of the surface modification was demonstrated by significantly improved solubility and stability in both water and cell culture medium, and further quantified by zeta-potential analysis. The grafted MWNTs exhibited relatively low bioreactivity on human immortal alveolar epithelial type 1-like cells (TT1) following 24h exposure as demonstrated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) and lactate dehydrogenase release (LDH) assays. The exposure of TT1 cells to MWNTs suppressed the release of the inflammatory mediators, interleukin 6 (IL-6) and interleukin 8 (IL-8). TEM cell uptake studies indicated efficient cellular entry of MWNTs into TT1 cells, via a range of mechanisms. Cationic MWNTs showed a more substantial interaction with TT1 cell membranes than anionic MWNTs, demonstrating a surface charge effect on cell uptake. PMID:24631251

  11. Metformin loaded non-ionic surfactant vesicles: optimization of formulation, effect of process variables and characterization

    PubMed Central


    Background Metformin an oral hypoglycemic has been widely used as a fist line of treatment of Type II Diabetes but in a very high dose 2–3 times a day and moreover suffers from a number of side effects like lactic acidosis, gastric discomfort, chest pain, allergic reactions being some of them. The present work was conducted with the aim of sustaining the release of metformin so as to decrease its side effects and also reduce its dosing frequency using a novel delivery system niosomes (non-ionic surfactant vesicles). Non-ionic surfactant vesicles of different surfactants were prepared using thin film hydration technique and were investigated for morphology, entrapment, in-vitro release, TEM (transmission electron microscopy) and physical stability. Optimized formulation was further studied for the effect of Surfactant concentration, DCP (Dicetyl phosphate), Surfactant: cholesterol ratio and volume of hydration. The release studies data was subjected to release kinetics models. Results The prepared vesicles were uniform and spherical in size. Optimized formulation MN3 entrapped the drug with 84.50±0.184 efficiency in the vesicles of the size 487.60±2.646 and showed the most sustained release of 73.89±0.126. Also it was resulted that 100 molar concentration of cholesterol and surfactant, Presence of DCP, equimolar ratio of span 60: cholesterol and 15 ml of volume of hydration were found to be optimum for miosome preparation. Conclusions The present work concluded metformin loaded niosomes to be effective in sustaining the drug release leading to decreased side effects and increased patient compliance. PMID:23351604


    EPA Science Inventory

    A model for the removal of water-soluble organic materials from water by carbon-filled, buoyant packets and panels is described. Based on this model, equations are derived for the removal of dissolved organic compounds from waterways by buoyant packets that are either (a) cycled ...

  13. Profiling and relationship of water-soluble sugar and protein compositions in soybean seeds.


    Yu, Xiaomin; Yuan, Fengjie; Fu, Xujun; Zhu, Danhua


    Sugar and protein are important quality traits in soybean seeds for making soy-based food products. However, the investigations on both compositions and their relationship have rarely been reported. In this study, a total of 35 soybean germplasms collected from Zhejiang province of China, were evaluated for both water-soluble sugar and protein. The total water-soluble sugar (TWSS) content of the germplasms studied ranged from 84.70 to 140.91 mg/g and the water-soluble protein (WSP) content varied from 26.5% to 36.0%. The WSP content showed positive correlations with the TWSS and sucrose contents but negative correlations with the fructose and glucose contents. The clustering showed the 35 germplasms could be divided into four groups with specific contents of sugar and protein. The combination of water-soluble sugar and protein profiles provides useful information for future breeding and genetic research. This investigation will facilitate future work for seed quality improvement. PMID:26593554

  14. Polyoxometalate-directed assembly of water-soluble AgCl nanocubes.


    Neyman, Alevtina; Wang, Yifeng; Sharet, Shelly; Varsano, Neta; Botar, Bogdan; Kögerler, Paul; Meshi, Louisa; Weinstock, Ira A


    "Out-of-pocket" association of Ag(+) to the tetradentate defect site of mono-vacant Keggin and Wells-Dawson polyoxometalate (POM) cluster-anions is used to direct the formation of water-soluble AgCl nanocubes. PMID:22252035


    Technology Transfer Automated Retrieval System (TEKTRAN)

    Surface and interfacial tensions with hexadecane were measured for starch and water soluble starch ester solutions in order to determine their potential as stabilizers or emulsifiers. The surface tension for an acid hydrolysed starch (maltodextrin) initially declined with concentration and then rea...

  16. Simultaneous Determination of Water Soluble Vitamins in Dietary Supplements and Fortified Foods by LC-MS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent work in our laboratory has focused on development of LC methods with diode array and/or mass spectrometry (ms) detection for the simultaneous determination in supplement tablets and fortified foods of several water-soluble vitamins (WSV) including: thiamin, niacin, pyridoxine, pantothenic ac...

  17. Fabrication and multifunctional properties of ultrasmall water-soluble tungsten oxide quantum dots.


    Peng, Huaping; Liu, Pan; Lin, Danwei; Deng, Yani; Lei, Yun; Chen, Wei; Chen, Yuanzhong; Lin, Xinhua; Xia, Xinghua; Liu, Ailin


    A facile and green method has been demonstrated to synthesize ultrasmall tungsten oxide quantum dots (WOx QDs). The water-soluble WOx QDs present high luminescence stability, strong peroxidase-like activity, and excellent electrochemiluminescence properties. This work provides an eco-friendly strategy to prepare multifunctional WOx QDs, and opens the door for bioapplications of the WOx QDs. PMID:27381501

  18. Water-soluble lead in cathode ray tube funnel glass melted in a reductive atmosphere.


    Okada, Takashi


    In the reduction-melting process, lead can be recovered from cathode ray tube funnel glass (PbO=25wt%); however, resulting glass residues still contain approximately 1-2wt% of unrecovered lead. For environmental protection in the residue disposal or recycling, it is important to evaluate the quantities of water-soluble species among the unrecovered lead. This study examined water-soluble lead species generated in the reduction-melting process of the funnel glass and factors determining their generation. In the reduction-melting, metallic lead was generated by reducing lead oxides in the glass, and a part of the metallic lead remained in the glass residue. Such unrecovered metallic lead can dissolve in water depending on its pH level and was regarded as water-soluble lead. When 10g Na2CO3 was added to 20g funnel glass during reduction-melting, the resulting glass contained high concentrations of sodium. In a water leaching of the glass, the obtained leachate was alkalized by the sodium-rich glass (pH=12.7-13.0). The unrecovered metallic lead in the glass was extracted in the alkalized leachate. The quantity of the unrecovered metallic lead (water-soluble lead) in the glass decreased when the melting time, melting temperature, and carbon dosage were controlled during reduction-melting. PMID:27209518

  19. Antimicrobial Effect of Water-Soluble Muscadine Seed Extracts on Escherichia coli O157:H7

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water-soluble extracts were prepared from purple (cultivar Ison) and bronze (cultivar Carlos) muscadine seeds with or without heating. The Ison extracts had strong antimicrobial activity against a cocktail of three strains of Escherichia coli O157:H7. This extract had higher acidity (pH 3.39 to 3.43...

  20. Inactivation of Enterobacter sakazakii by Water-soluble Muscadine Seed Extracts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hot and cold water-soluble muscadine (Vitis rotundifolia) seed extracts and their polar and polyphenol fractions from two Muscadine cultivars (‘Ison’, purple and ‘Carlos’, bronze) were investigated for their inhibition of Enterobacter sakazakii. The heat treatment on each seed extract not only incre...

  1. 40 CFR 799.6786 - TSCA water solubility: Generator column method.

    Code of Federal Regulations, 2013 CFR


    ... 40 Protection of Environment 33 2013-07-01 2013-07-01 false TSCA water solubility: Generator...: Generator column method. (a) Scope—(1) Applicability. This section is intended to meet the testing... the saturated solutions produced by the generator column. After extraction onto a...

  2. 40 CFR 799.6786 - TSCA water solubility: Generator column method.

    Code of Federal Regulations, 2014 CFR


    ... 40 Protection of Environment 32 2014-07-01 2014-07-01 false TSCA water solubility: Generator...: Generator column method. (a) Scope—(1) Applicability. This section is intended to meet the testing... the saturated solutions produced by the generator column. After extraction onto a...

  3. 40 CFR 799.6786 - TSCA water solubility: Generator column method.

    Code of Federal Regulations, 2012 CFR


    ... 40 Protection of Environment 33 2012-07-01 2012-07-01 false TSCA water solubility: Generator...: Generator column method. (a) Scope—(1) Applicability. This section is intended to meet the testing... the saturated solutions produced by the generator column. After extraction onto a...


    EPA Science Inventory

    The objective of this study was to determine the partitioning of water soluble azo dyes in the activated sludge process (ASP). Azo dyes are of concern because some of the dyes, dye precursors , and/or their degradation products such as aromatic amines (which are also dye precurso...

  5. Photocatalytic hydrogen production from a simple water-soluble [FeFe]-hydrogenase model system.


    Cao, Wei-Ning; Wang, Feng; Wang, Hong-Yan; Chen, Bin; Feng, Ke; Tung, Chen-Ho; Wu, Li-Zhu


    Combined with a simple water soluble [FeFe]-hydrogenase mimic 1, Ru(bpy)(3)(2+) and ascorbic acid enable hydrogen production photocatalytically. More than 88 equivalents of H(2) were achieved in water, which is much better than that obtained in an organic solvent or a mixture of organic solvent and water. PMID:22772838

  6. Defensive strategies in Geranium sylvaticum, Part 2: Roles of water-soluble tannins, flavonoids and phenolic acids against natural enemies.


    Tuominen, Anu


    Geranium sylvaticum is a common herbaceous plant in Fennoscandia, which has a unique phenolic composition. Ellagitannins, proanthocyanidins, galloylglucoses, gallotannins, galloyl quinic acids and flavonoids possess variable distribution in its different organs. These phenolic compounds are thought to have an important role in plant-herbivore interactions. The aim of this study was to quantify these different water-soluble phenolic compounds and measure the biological activity of the eight organs of G. sylvaticum. Compounds were characterized and quantified using HPLC-DAD/MS, in addition, total proanthocyanidins were determined by BuOH-HCl assay and total phenolics by the Folin-Ciocalteau method. Two in vitro biological activity measurements were used: the prooxidant activity was measured by the browning assay and antioxidant activity by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Organ extracts were fractionated using column chromatography on Sephadex LH-20 and the activities of fractions was similarly measured to evaluate which polyphenol groups contributed the most to the biological activity of each organ. The data on the activity of fractions were examined by multivariate data analysis. The water-soluble extracts of leaves and pistils, which contained over 30% of the dry weight as ellagitannins, showed the highest pro-oxidant activity among the organ extracts. Fraction analysis revealed that flavonoids and galloyl quinic acids also exhibited high pro-oxidant activity. In contrast, the most antioxidant active organ extracts were those of the main roots and hairy roots that contained high amounts of proanthocyanidins in addition to ellagitannins. Analysis of the fractions showed that especially ellagitannins and galloyl quinic acids have high antioxidant activity. We conclude that G. sylvaticum allocates a significant amount of tannins in those plant parts that are important to the fitness of the plant and susceptible to natural enemies, i

  7. Nanoformulation and encapsulation approaches for poorly water-soluble drug nanoparticles.


    Wais, Ulrike; Jackson, Alexander W; He, Tao; Zhang, Haifei


    During the last few decades the nanomedicine sector has emerged as a feasible and effective solution to the problems faced by the high percentage of poorly water-soluble drugs. Decreasing the size of such drug compounds to the nanoscale can significantly change their physical properties, which lays the foundation for the use of nanomedicine for pharmaceutical applications. Various techniques have been developed to produce poorly water-soluble drug nanoparticles, mainly to address the poor water-soluble issues but also for the efficient and targeted delivery of such drugs. These techniques can be generally categorized into top-down, bottom-up and encapsulation approaches. Among them, the top-down approaches have been the main choice for industrial preparation of drug nanoparticles while other methods are actively investigated by researchers. In this review, we aim to give a comprehensive overview and latest progress of the top-down, bottom-up, and encapsulation methods for the preparation of poorly water-soluble drug nanoparticles and how solvents and additives can be selected for these methods. In addition to the more industrially applied top-down approaches, the review is focused more on bottom-up and encapsulation methods, particularly covering supercritical fluid-related methods, cryogenic techniques, and encapsulation with dendrimers and responsive block copolymers. Some of the approved and mostly used nanodrug formulations on the market are also covered to demonstrate the applications of poorly water-soluble drug nanoparticles. This review is complete with perspectives on the development and challenges of fabrication techniques for more effective nanomedicine. PMID:26731460

  8. Nanoformulation and encapsulation approaches for poorly water-soluble drug nanoparticles

    NASA Astrophysics Data System (ADS)

    Wais, Ulrike; Jackson, Alexander W.; He, Tao; Zhang, Haifei


    During the last few decades the nanomedicine sector has emerged as a feasible and effective solution to the problems faced by the high percentage of poorly water-soluble drugs. Decreasing the size of such drug compounds to the nanoscale can significantly change their physical properties, which lays the foundation for the use of nanomedicine for pharmaceutical applications. Various techniques have been developed to produce poorly water-soluble drug nanoparticles, mainly to address the poor water-soluble issues but also for the efficient and targeted delivery of such drugs. These techniques can be generally categorized into top-down, bottom-up and encapsulation approaches. Among them, the top-down approaches have been the main choice for industrial preparation of drug nanoparticles while other methods are actively investigated by researchers. In this review, we aim to give a comprehensive overview and latest progress of the top-down, bottom-up, and encapsulation methods for the preparation of poorly water-soluble drug nanoparticles and how solvents and additives can be selected for these methods. In addition to the more industrially applied top-down approaches, the review is focused more on bottom-up and encapsulation methods, particularly covering supercritical fluid-related methods, cryogenic techniques, and encapsulation with dendrimers and responsive block copolymers. Some of the approved and mostly used nanodrug formulations on the market are also covered to demonstrate the applications of poorly water-soluble drug nanoparticles. This review is complete with perspectives on the development and challenges of fabrication techniques for more effective nanomedicine.

  9. Structural Characterization and Reactivity of Pyrogenic Water-Soluble Organic Matter Derived from Biomass Combustion

    NASA Astrophysics Data System (ADS)

    Norwood, M. J.; Louchouarn, P.; Kuo, L.


    Combustion processes, whether from natural or anthropogenic origin, are major sources of particulate matter (PM), black carbon (BC), and volatile organic carbon to the atmosphere as well as soils and aquatic environments. The ubiquitous presence of biomass combustion by-products in atmospheric particles and soils could potentially lead to a large transfer of pyrogenic water-soluble organic matter (Pyr-WSOM) to the surface of watersheds and aquatic systems. In spite of this, there is a dearth of studies that have characterized the sources, and particularly the fate, of Pyr-WSOM to aquatic systems. In the present study, Pyr-WSOM was extracted from plant-derived chars (feedstocks: honey mesquite, cordgrass, and loblolly pine) produced at a range of temperatures (150-850C), and were then characterized using elemental analyses and ATR-FTIR. Low temperature (250C) Pyr-WSOM, extracted from honey mesquite and cordgrass biochars, were then incubated with aliquots of filtered water from the Trinity River (TX) for one month under dark conditions. Consistent with prior studies on combustion molecular markers such as anhydrosugars and methoxylated phenols, the total amount of dissolved organic carbon (DOC) released from biochars peaks around 200-250C and then decreases with increasing temperature of combustion. Elemental and structural analyses of biochar-derived WSOM reflect the selective solubility of certain functional groups. For example, despite the predominance of aromatic units and soot structures in biochars formed at high temperatures, such functionalities are not as predominant in their respective Pyr-WSOM. In addition, the high proportion of O-containing functionalities suggests that Pyr-WSOM may be more biodegradable than the particulate residues of biomass combustion. Indeed, low temperature Pyr-WSOM decomposed rapidly with half-lives ranging ~30 days for total DOC to 4-5 days for specific molecular markers of biomass combustion. These rapid turnover rates are in

  10. Characterization of the size-segregated water-soluble inorganic ions at eight Canadian rural sites

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Vet, R.; Wiebe, A.; Mihele, C.; Sukloff, B.; Chan, E.; Moran, M. D.; Iqbal, S.


    Size-segregated water-soluble inorganic ions, including particulate sulphate (SO42-), nitrate (NO3-), ammonium (NH4+), chloride (Cl-), and base cations (K+, Na+, Mg2+, Ca2+), were measured using a Micro-Orifice Uniform Deposit Impactor (MOUDI) during fourteen short-term field campaigns at eight locations in both polluted and remote regions of eastern and central Canada. The size distributions of SO42- and NH4+ were unimodal, peaking at 0.3-0.6 µm in diameter, during most of the campaigns, although a bimodal distribution was found during one campaign and a trimodal distribution was found during another campaign made at a coastal site. SO42- peaked at slightly larger sizes in the cold seasons (0.5-0.6 µm) compared to the hot seasons (0.3-0.4 µm) due to the higher relative humidity in the cold seasons. The size distributions of NO3- were unimodal, peaking at 4.0-7.0 µm during the warm-season campaigns, and bimodal, with one peak at 0.3-0.6 µm and another at 4-7 µm during the cold-season campaigns. A unimodal size distribution, peaking at 4-6 µm, was found for Cl-, Na+, Mg2+, and Ca2+ during approximately half of the campaigns and a bimodal distribution, with one peak at 2 µm and the other at 6 µm, was found during the rest of the campaigns. For K+, a bimodal distribution, with one peak at 0.3 µm and the other at 4 µm, was observed during most of the campaigns. Seasonal contrasts in the size-distribution profiles suggest that emission sources and air mass origins were the major factors controlling the size distributions of the primary aerosols while meteorological conditions were more important for the secondary aerosols. The dependence of the particle acidity on the particle size from the nucleation mode to the accumulation mode was not consistent from site to site or from season to season. Particles in the accumulation mode were more acidic than those in the nucleation mode when submicron particles were in the state of strong acidity; however, when

  11. Invisible Security Ink Based on Water-Soluble Graphitic Carbon Nitride Quantum Dots.


    Song, Zhiping; Lin, Tianran; Lin, Lihua; Lin, Sen; Fu, Fengfu; Wang, Xinchen; Guo, Liangqia


    Stimuli-responsive photoluminescent (PL) materials have been widely used as fluorescent ink for data security applications. However, traditional fluorescent inks are limited in maintaining the secrecy of information because the inks are usually visible by naked eyes either under ambient light or UV-light illumination. Here, we introduced metal-free water-soluble graphitic carbon nitride quantum dots (g-CNQDs) as invisible security ink for information coding, encryption, and decryption. The information written by the g-CNQDs is invisible in ambient light and UV light, but it can be readable by a fluorescence microplate reader. Moreover, the information can be encrypted and decrypted by using oxalic acid and sodium bicarbonate as encryption reagent and decryption reagent, respectively. Our findings provide new opportunities for high-level information coding and protection by using water-soluble g-CNQDs as invisible security ink. PMID:26797811

  12. Formation of water-soluble soybean polysaccharides from spent flakes by hydrogen peroxide treatment.


    Pierce, Brian C; Wichmann, Jesper; Tran, Tam H; Cheetamun, Roshan; Bacic, Antony; Meyer, Anne S


    In this paper we propose a novel chemical process for the generation of water-soluble polysaccharides from soy spent flake, a by-product of the soy food industry. This process entails treatment of spent flake with hydrogen peroxide at an elevated temperature, resulting in the release of more than 70% of the original insoluble material as high molar mass soluble polysaccharides. A design of experiment was used to quantify the effects of pH, reaction time, and hydrogen peroxide concentration on the reaction yield, average molar mass, and free monosaccharides generated. The resulting product is low in protein, fat, and minerals and contains predominantly water-soluble polysaccharides of high molar mass, including arabinan, type I arabinogalactan, homogalacturonan, xyloglucan, rhamnogalacturonan, and (glucurono)arabinoxylan. This treatment provides a straightforward approach for generation of soluble soy polysaccharides and opens a new range of opportunities for this abundant and underutilized material in future research and industrial applications. PMID:27083842

  13. Consequences of chirality on the dynamics of a water-soluble supramolecular polymer.


    Baker, Matthew B; Albertazzi, Lorenzo; Voets, Ilja K; Leenders, Christianus M A; Palmans, Anja R A; Pavan, Giovanni M; Meijer, E W


    The rational design of supramolecular polymers in water is imperative for their widespread use, but the design principles for these systems are not well understood. Herein, we employ a multi-scale (spatial and temporal) approach to differentiate two analogous water-soluble supramolecular polymers: one with and one without a stereogenic methyl. Initially aiming simply to understand the molecular behaviour of these systems in water, we find that while the fibres may look identical, the introduction of homochirality imparts a higher level of internal order to the supramolecular polymer. Although this increased order does not seem to affect the basic dimensions of the supramolecular fibres, the equilibrium dynamics of the polymers differ by almost an order of magnitude. This report represents the first observation of a structure/property relationship with regard to equilibrium dynamics in water-soluble supramolecular polymers. PMID:25698667

  14. Consequences of chirality on the dynamics of a water-soluble supramolecular polymer

    PubMed Central

    Baker, Matthew B.; Albertazzi, Lorenzo; Voets, Ilja K.; Leenders, Christianus M.A.; Palmans, Anja R.A.; Pavan, Giovanni M.; Meijer, E.W.


    The rational design of supramolecular polymers in water is imperative for their widespread use, but the design principles for these systems are not well understood. Herein, we employ a multi-scale (spatial and temporal) approach to differentiate two analogous water-soluble supramolecular polymers: one with and one without a stereogenic methyl. Initially aiming simply to understand the molecular behaviour of these systems in water, we find that while the fibres may look identical, the introduction of homochirality imparts a higher level of internal order to the supramolecular polymer. Although this increased order does not seem to affect the basic dimensions of the supramolecular fibres, the equilibrium dynamics of the polymers differ by almost an order of magnitude. This report represents the first observation of a structure/property relationship with regard to equilibrium dynamics in water-soluble supramolecular polymers. PMID:25698667

  15. Consequences of chirality on the dynamics of a water-soluble supramolecular polymer

    NASA Astrophysics Data System (ADS)

    Baker, Matthew B.; Albertazzi, Lorenzo; Voets, Ilja K.; Leenders, Christianus M. A.; Palmans, Anja R. A.; Pavan, Giovanni M.; Meijer, E. W.


    The rational design of supramolecular polymers in water is imperative for their widespread use, but the design principles for these systems are not well understood. Herein, we employ a multi-scale (spatial and temporal) approach to differentiate two analogous water-soluble supramolecular polymers: one with and one without a stereogenic methyl. Initially aiming simply to understand the molecular behaviour of these systems in water, we find that while the fibres may look identical, the introduction of homochirality imparts a higher level of internal order to the supramolecular polymer. Although this increased order does not seem to affect the basic dimensions of the supramolecular fibres, the equilibrium dynamics of the polymers differ by almost an order of magnitude. This report represents the first observation of a structure/property relationship with regard to equilibrium dynamics in water-soluble supramolecular polymers.

  16. Physico-chemical qualification of a universal portable sampler for aerosols and water-soluble gases

    NASA Astrophysics Data System (ADS)

    Roux, Jean-Maxime; Sarda-Estève, Roland


    Developing a universal portable air sampler based on electrostatic precipitation. The challenge is to collect micro and nanoparticles, microorganisms as well as toxic molecules with a portable device. Electrostatic precipitation is an efficient and gentle method to collect airborne microorganisms and preserve their cultivability. But the collection of toxic gases required is not possible in such a device. The collection of such gases requires a liquid into which they have to be solubilized. Two concepts are being evaluated. The first one is based on electrospray. The goal is to investigate the collection efficiency of water-soluble gases. The second concept is based on the semi-humid electrostatic precipitator. Their high collection efficiencies for particles were already demonstrated. In the present study they are both tested with water-soluble gases. Concentrations are measured in the liquid solution by Ion Chromatography and in the gas phase by Proton Transfer Reaction Mass Spectrometry.

  17. Photophysical Properties and Singlet Oxygen Generation Efficiencies of Water-Soluble Fullerene Nanoparticles

    PubMed Central

    Stasheuski, Alexander S; Galievsky, Victor A; Stupak, Alexander P; Dzhagarov, Boris M; Choi, Mi Jin; Chung, Bong Hyun; Jeong, Jin Young


    As various fullerene derivatives have been developed, it is necessary to explore their photophysical properties for potential use in photoelectronics and medicine. Here, we address the photophysical properties of newly synthesized water-soluble fullerene-based nanoparticles and polyhydroxylated fullerene as a representative water-soluble fullerene derivative. They show broad emission band arising from a wide-range of excitation energies. It is attributed to the optical transitions from disorder-induced states, which decay in the nanosecond time range. We determine the kinetic properties of the singlet oxygen (1O2) luminescence generated by the fullerene nanoparticles and polyhydroxylated fullerene to consider the potential as photodynamic agents. Triplet state decay of the nanoparticles was longer than 1O2 lifetime in water. Singlet oxygen quantum yield of a series of the fullerene nanoparticles is comparably higher ranging from 0.15 to 0.2 than that of polyhydroxylated fullerene, which is about 0.06. PMID:24893622

  18. Method of cross-linking polyvinyl alcohol and other water soluble resins

    NASA Technical Reports Server (NTRS)

    Phillipp, W. H.; May, C. E.; Hsu, L. C.; Sheibley, D. W. (Inventor)


    A self supporting sheet structure comprising a water soluble, noncrosslinked polymer such as polyvinyl alcohol which is capable of being crosslinked by reaction with hydrogen atom radicals and hydroxyl molecule radicals is contacted with an aqueous solution having a pH of less than 8 and containing a dissolved salt in an amount sufficient to prevent substantial dissolution of the noncrosslinked polymer in the aqueous solution. The aqueous solution is then irradiated with ionizing radiation to form hydrogen atom radicals and hydroxyl molecule radicals and the irradiation is continued for a time sufficient to effect crosslinking of the water soluble polymer to produce a water insoluble polymer sheet structure. The method has particular application in the production of battery separators and electrode envelopes for alkaline batteries.

  19. Synthesis and characterization of a hyper-branched water-soluble β-cyclodextrin polymer.


    Trotta, Francesco; Caldera, Fabrizio; Cavalli, Roberta; Mele, Andrea; Punta, Carlo; Melone, Lucio; Castiglione, Franca; Rossi, Barbara; Ferro, Monica; Crupi, Vincenza; Majolino, Domenico; Venuti, Valentina; Scalarone, Dominique


    A new hyper-branched water-soluble polymer was synthesized by reacting β-cyclodextrin with pyromellitic dianhydride beyond the critical conditions that allow the phenomenon of gelation to occur. The molar ratio between the monomers is a crucial parameter that rules the gelation process. Nevertheless, the concentration of monomers in the solvent phase plays a key role as well. Hyper-branched β-cyclodextrin-based polymers were obtained performing the syntheses with excess of solvent and cross-linking agent, and the conditions for critical dilution were determined experimentally. A hyper-branched polymer with very high water solubility was obtained and fully characterized both as for its chemical structure and for its capability to encapsulate substances. Fluorescein was used as probe molecule to test the complexation properties of the new material. PMID:25550720

  20. Chemical synthesis of water-soluble, chiral conducting-polymer complexes


    Wang, Hsing-Lin; McCarthy, Patrick A.; Yang, Sze Cheng


    The template-guided synthesis of water-soluble, chiral conducting polymer complexes is described. Synthesis of water-soluble polyaniline complexes is achieved by carefully controlling the experimental parameters such as; acid concentration, ionic strength, monomer/template ratio, total reagent concentration, and order of reagent addition. Chiral (helical) polyaniline complexes can be synthesized by addition of a chiral inducing agent (chiral acid) prior to polymerization, and the polyaniline helix can be controlled by the addition of the (+) or (-) form of the chiral acid. Moreover the quantity of chiral acid and the salt content has a significant impact on the degree of chirality in the final polymer complexes. The polyaniline and the template have been found to be mixed at the molecular level which results in chiral complexes that are robust through repeated doping and dedoping cycles.

  1. Synthesis, Characterization and Application of Water-soluble Gold and Silver Nanoclusters

    NASA Astrophysics Data System (ADS)

    Kumar, Santosh

    The term `nanotechnology' has emerged as a buzzword since the last few decades. It has found widespread applications across disciplines, from medicine to energy. The synthesis of gold and silver nanoclusters has found much excitement, due to their novel material properties. Seminal work by various groups, including ours, has shown that the size of these clusters can be controlled with atomic precision. This control gives access to tuning the optical and electronic properties. The majority of nanoclusters reported thus far are not water soluble, which limit their applications in biology that requires water-solubility. Going from organic to aqueous phase is by no means a simple task, as it is associated with many challenges. Their stability in the presence of oxygen, difficulty in characterization, and separation of pure nanoclusters are some of the major bottlenecks associated with the synthesis of water-soluble gold nanoclusters. Water-soluble gold nanoclusters hold great potential in biological labeling, bio-catalysis and nano-bioconjugates. To overcome this problem, a new ligand with structural rigidity is needed. After considering various possibilities, we chose Captopril as a candidate ligand. In my thesis research, the synthesis of Au25 nanocluster capped with captopril has been reported. Captopril-protected Au25 nanocluster showed significantly higher thermal stability and enhanced chiroptical properties than the Glutathione-capped cluster, which confirms our initial rationale, that the ligand is critical in protecting the nanocluster. The optical absorption properties of these Au25 nanoclusters are studied and compared to the plasmonic nanoparticles. The high thermal stability and solubility of Au25 cluster capped with Captopril motivated us to explore this ligand for the synthesis of other gold clusters. Captopril is a chiral molecule with two chiral centers. The chiral ligand can induce chirality to the overall cluster, even if the core is achiral

  2. Comparison of water solubilities by the flask and micro-column methods

    SciTech Connect

    Hashimoto, Y.; Tokura, K.; Ozaki, K.; Strachan, W.M.J.


    A comparative examination of the two procedures of the ''OECD Test Guildeline: Water Solubility'' was undertaken using carbazole, fluoranthene, anthracene, hexachlorobenzene, p-nitroaniline and diphenylamine. The flask method was modified to provide for dissolution of the solute from the surface of glass beads. By the proposed flask method, one can accurately measure the water solubility down to the order of 10 as well as those of the order of %. The micro-column method, which requires a number of concentration determinations to ensure that a saturated solution has been obtained, is recommended for the solubility range of 10 mg/L through 10 The flask method using the procedures described in this study, covers the range of solubility above 10 with only two determinations one being a simple preliminary test and the other a precise measurement.

  3. Preparation of starch macrocellular foam for increasing the dissolution rate of poorly water-soluble drugs.


    Zhao, Ying; Wu, Chao; Zhao, Zongzhe; Hao, Yanna; Xu, Jie; Yu, Tong; Qiu, Yang; Jiang, Jie


    Starch macrocellular foam (SMF), a novel natural bio-matrix material, was prepared by the hard template method in order to improve the dissolution rate and oral bioavailability of poorly water-soluble drugs. Nitrendipine (NDP) was chosen as a model drug and was loaded into SMF by the solvent evaporation method. SMF and the loaded SMF samples (NDP-SMF) were characterized by scanning electron microscopy, differential scanning calorimetry, X-ray powder diffraction and Fourier transform infrared spectroscopy. In vitro drug release studies showed that SMF significantly increased the dissolution rate of NDP. In vivo studies showed that the NDP-SMF tablets clearly increased the oral bioavailability of NDP in comparison with the reference commercial tablets. All the results obtained demonstrated that SMF was a promising carrier for the oral delivery of poor water-soluble drugs. PMID:26166407

  4. [Analysis and identification of water soluble components of water buffalo horn].


    Liu, Rui; Duan, Jin-ao; Wu, Hao; Liu, Pei; Shang, Er-xin; Qian, Da-wei


    This study is to analyze and identify the water soluble components of water buffalo horn (Bubali Cornu, WBH), and also establish a method for investigating these components. Shotgun proteomic analysis identified proteins in WBH aqueous extraction: keratin, collagen, desmoglein, etc. Ultrafiltration and LC-MS/MS were used to separate and identify the peptides in WBH aqueous extract, as a result, identified peptides were mainly derived from nonspecific degradation products of keratin and collagen, which including C-terminal peptides and non C-terminal peptides. Hypoxanthine, uridine, guanosine, and adenosine were identified by comparing with the standards. The strategy in present study could be used in analyzing water soluble components of animal horn derived TCM. It provides a reference for investigation of the material basis of animal horn derived TCM. PMID:26234143

  5. Water soluble nanocurcumin extracted from turmeric challenging the microflora from human oral cavity.


    Gopal, Judy; Muthu, Manikandan; Chun, Se-Chul


    Water soluble nanocurcumin prepared from commercial turmeric powders was compared against ethanol extracted curcumin particles. The oral microflora from five different human volunteers was collected and the efficacy of solvent extracted curcumin versus water extracted nanocurcumin was demonstrated. Nanocurcumin activity against oral microflora confirms its antimicrobial potency. Confocal laser scanning microscopic results revealed the enhanced entry of nanocurcumin particles into microbial cells. The nanosized nature of nanocurcumin appears to have led to increased cellular interaction and thereby efficient destruction of microbial cells in the mouth. In addition, solubility of nanocurcumin is also believed to be a crucial factor behind its successful antimicrobial activity. This study proves that the bioactivity of a compound is greatly influenced by its solubility in water. This work recommends the use of water soluble nanocurcumin (extracted from turmeric) as potent substitute for curcumin in dental formulations. PMID:27283711

  6. Design of Chitosan and Its Water Soluble Derivatives-Based Drug Carriers with Polyelectrolyte Complexes

    PubMed Central

    Wu, Qing-Xi; Lin, Dong-Qiang; Yao, Shan-Jing


    Chitosan, the cationic polysaccharide derived from the natural polysaccharide chitin, has been studied as a biomaterial for more than two decades. As a polycationic polymer with favorable properties, it has been widely used to form polyelectrolyte complexes with polyanions for various applications in drug delivery fields. In recent years, a growing number of studies have been focused on the preparation of polyelectrolyte complexes based on chitosan and its water soluble derivatives. They have been considered well-suited as biomaterials for a number of vital drug carriers with targeted/controlled release profiles, e.g., films, capsules, microcapsules. In this work, an overview highlights not only the favorable properties of chitosan and its water soluble derivatives but also the good performance of the polyelectrolyte complexes produced based on chitosan. Their various types of applications as drug carriers are reviewed in detail. PMID:25532565

  7. Bioavailability of water-soluble CoQ10 in beagle dogs.


    Prosek, Mirko; Butinar, Janos; Lukanc, Barbara; Fir, Maja Milivojevic; Milivojevic, Luka; Krizman, Mitja; Smidovnik, Andrej


    The bioavailability of a novel water-soluble inclusion complex of CoQ10, prepared in our laboratory was determined and compared with the bioavailability of commercially available oil-based form of CoQ10. Experimental work consisted of single dose comparative bioavailability study on seven beagle dogs, with a 14-day washout period between treatments. Identification and quantification of CoQ10 was done with HPLC-MS method using positive APCI ionization and SIM mode, M+ m/z 863.4. The bioavailability results confirm that the water-soluble formulation has nearly three times higher AUC(0-48 h), two times higher Cmax, and Tmax is shortened from 6 to 4 h. PMID:18495407

  8. Water-soluble polymer exfoliated graphene: as catalyst support and sensor.


    Wang, Haibo; Xia, Baoyu; Yan, Ya; Li, Nan; Wang, Jing-Yuan; Wang, Xin


    In this paper, we obtained various water-soluble polymer functionalized graphene in dimethyl sulfoxide under ultrasonication. The atomic force microscope analysis and control experiment shows the water-soluble polymer is the crucial part to help solvent molecules separate interlayer. Such polymer/graphene exhibits high conductivity and tunable surface property, as confirmed by the selected area electron diffraction and Raman and electrochemical impedance spectroscopy. As a result, a catalyst based on polyvinyl pyrrolidone (PVP)/graphene shows better methanol oxidation performance than that based on PVP/reduced graphene oxide. By changing to another polymer, poly(4-vinylpyridine)/graphene shows a stable and reversible response to pH, and demonstrates its potential for sensor application. PMID:23574310

  9. Anomalous thickness variation of the foam films stabilized by weak non-ionic surfactants.


    Qu, Xuan; Wang, Liguang; Karakashev, Stoyan I; Nguyen, Anh V


    The constant thickness (H) of metastable free films of various non-ionic surfactant solutions was measured at surfactant concentrations less than the critical micelle concentrations or solubility limits with fixed 5x10(-5) M sodium chloride (NaCl) serving as the background electrolyte. The surfactants include n-pentanol, n-octanol, methyl isobutyl carbinol (MIBC), polypropylene glycol (PPG-400), tetraethylene glycol monooctyl ether (C(8)E(4)), and tetraethylene glycol monodecyl ether (C(10)E(4)). H was interferometrically measured. For each surfactant in this study, the H-versus-surfactant-concentration curve finds a peak at a concentration around 5x10(-6)-1x10(-5) M and a valley at a higher concentration. The measured H values were compared to those predicted from the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory, which considers solely the contribution from electrostatic double-layer repulsion with van der Waals attraction being neglected in the present work. In determining the double-layer repulsion, the ionic strength was determined from the electrolytic conductivity measurement of the film-forming solutions and the surface potential was estimated from the zeta-potential measurement of air bubbles. It was found that the DLVO theory failed to explain the thickness variance with surfactant concentration, implying that additional non-DLVO attractive forces might be required to explain the experimental results. Finally, the possible origins of these attractive forces were discussed. PMID:19539299

  10. Photodegradation mechanism and rate improvement of chlorinated aromatic dye in non-ionic surfactant solutions.


    Ma, C W; Chu, W


    A typical insoluble chlorinated aromatic dye (CAD), disperse red (DR), was used to explore the reaction mechanism and kinetics of photodegradation in non-ionic surfactant solutions. The use of an additional hydrogen source and photosensitizer is also studied to improve the decay rates. The decay rate of dye in surfactants depends on the Km of surfactants and their ability to offering an effective hydrogen source. The photodegradation of CAD can be divided into three stages: the initial lag stage. the fast degradation stage and the final retardation stage. The lag stage will vanish and the decay rates of dye can be greatly improved by 2.5-3.6 times after adding an additional hydrogen source (NaBH4) or photosensitizer (acetone) to the surfactant micellar solution. However, the use of an additional hydrogen source or photosensitizer has dosage limitations in such applications. The photoreduction of DR is the main reaction mechanism, in which photodechlorination is observed first with the generation of HCI as the final product, then followed by photodecolorization by breaking the azo bond of the chromophore. PMID:11394780

  11. Investigation of colloidal properties of modified silicone polymers emulsified by non-ionic surfactants.


    Purohit, Parag S; Kulkarni, Ravi; Somasundaran, P


    Functionalized silicones are a unique class of hybrid materials due to their simultaneous hydrophobic-oleophobic properties, which results in applications in a variety of surface modification techniques. Prior research has shown that changes in surface charge and turbidity of modified silicone emulsions as a function of pH have a marked effect on their performance in coating applications. The emulsion droplet size is also believed to play significant role in such coating applications. In this work, modified silicone polymer emulsions stabilized by non-ionic surfactants were studied using dynamic light scattering (dilute) and electroacoustic (concentrated) spectroscopy to monitor the emulsion droplet size. The dilute and concentrated regime studies showed the emulsion droplet to be in nanometer range with no appreciable change in size as a function of pH. Electroacoustic studies showed a small fraction of droplets to be present in the micron size range. The emulsions were examined using Cryo-TEM technique, and the effect of pH and dilution on hydrophobicity of nanodomains was studied by employing fluorescence spectroscopy. It is shown from pyrene excimer behavior that both the dilution and pH have an effect on emulsion stability with a presence of critical surfactant concentration after which the emulsion was destabilized. It is proposed that the emulsion stability characteristics and the particle size distribution both play a significant role in their ability to impart desired macro and nano surface properties to treated substrates through electrostatic interactions and selective binding. PMID:22796069

  12. Simulation of non-ionic surfactant micelle formation across a range of temperature and pressure

    NASA Astrophysics Data System (ADS)

    Custer, Gregory; Das, Payel; Matysiak, Silvina

    Non-ionic surfactants can, at certain concentrations and thermodynamic conditions, aggregate into micelles due to their amphiphilic nature. Our work looks at the formation and behavior of micelles at extremes of temperature and pressure. Due to the large system size and simulation time required to study micelle formation, we have developed a coarse-grained (CG) model of our system. This CG model represents each heavy atom with a single CG bead. We use the multibody Stillinger-Weber potential, which adds a three-body angular penalty to a two-body potential, to emulate hydrogen bonds in the system. We simulate the linear surfactant C12E5 , which has a nonpolar domain of 12 carbons and a polar domain of 5 ethers. Our CG model has been parameterized to match structural properties from all-atom simulations of single and dimer surfactant systems. Simulations were performed using a concentration above the experimental critical micelle concentration at 300K and 1atm. We observe an expected region of stable micelle formation at intermediate temperature, with a breakdown at high and low temperature, as well as at high pressure. The driving forces behind the destabilization of micelles and the mechanism of micelle formation at different thermodynamic conditions will be discussed.

  13. Immobilization of enzymes using non-ionic colloidal liquid aphrons (CLAs): Activity kinetics, conformation, and energetics.


    Ward, Keeran; Xi, Jingshu; Stuckey, David C


    This study seeks to examine the ability of non-ionic/non-polar Colloidial Liquid Aphrons (CLAs) to preserve enzyme functionality upon immobilization and release. CLAs consisting of micron-sized oil droplets surrounded by a thin aqueous layer stabilized by a mixture of surfactants, were formulated by direct addition (pre-manufacture addition) using 1% Tween 80/mineral oil and 1% Tween 20 and the enzymes lipase, aprotinin and α-chymotrypsin. The results of activity assays for both lipase and α-chymotrypsin showed that kinetic activity increased upon immobilization by factors of 7 and 5.5, respectively, while aprotinin retained approximately 85% of its native activity. The conformation of the enzymes released through desorption showed no significant alterations compared to their native state. Changes in pH and temperature showed that optimum conditions did not change after immobilization, while analysis of activation energy for the immobilized enzyme showed an increase in activity at higher temperatures. Furthermore, the effect of bound water within the aphron structure allowed for some degree of enzyme hydration, and this hydration was needed for an active conformation with results showing a decrease in ΔH* for the immobilized system compared to its native counterpart. PMID:26497856

  14. Effect of Non-ionic Surfactants and Its Role in K Intercalation in Electrolytic Manganese Dioxide

    NASA Astrophysics Data System (ADS)

    Biswal, Avijit; Tripathy, B. C.; Subbaiah, T.; Meyrick, D.; Ionescu, Mihail; Minakshi, Manickam


    The effect of non-ionic surface active agents (surfactants) Triton X-100 (TX-100) and Tween-20 (Tw-20) and their role in potassium intercalation in electrolytic manganese dioxide (EMD) produced from manganese cake has been investigated. Electrosynthesis of MnO2 in the absence or presence of surfactant was carried out from acidic MnSO4 solution obtained from manganese cake under optimized conditions. A range of characterization techniques, including field emission scanning electron microscopy, transmission electron microscopy (TEM), Rutherford back scattering (RBS), and BET surface area/porosity studies, was carried out to determine the structural and chemical characteristics of the EMD. Galvanostatic (discharge) and potentiostatic (cyclic voltammetric) studies were employed to evaluate the suitability of EMD in combination with KOH electrolyte for alkaline battery applications. The presence of surfactant played an important role in modifying the physicochemical properties of the EMD by increasing the surface area of the material and hence, enhancing its electrochemical performance. The TEM and RBS analyses of the discharged EMD (γ-MnO2) material showed clear evidence of potassium intercalation or at least the formation of a film on the MnO2 surface. The extent of intercalation was greater for EMD deposited in the presence of TX-100. Discharged MnO2 showed products of Mn2+ intermediates such as MnOOH and Mn3O4.

  15. Ethanol enhanced in vivo gene delivery with non-ionic polymeric micelles inhalation.


    Chao, Yen-Chin; Chang, Shwu-Fen; Lu, Shao-Chun; Hwang, Tzyh-Chang; Hsieh, Wei-Hsien; Liaw, Jiahorng


    Modifications of both carriers and host barriers have been investigated for efficient inhalation gene delivery to lung. Here we used a biocompatible, non-ionic poly(ethyleneoxide)-poly(propyleneoxide)-poly(ethyleneoxide) (PEO-PPO-PEO) polymeric micelles (PM) as a carrier and combined it with ethanol to enhance membrane penetration of delivered DNA. The inhalation delivery with six 100 microg doses of pCMV-Lac Z with PM co-formulated with 10%-40% ethanol to nude mice in 2 days at 8 h interval was performed. The beta-galatosidase (beta-Gal) activity was assessed using chlorophenol red-beta-d galactopyranoside (CPRG) and X-gal staining for quantitative and qualitative analysis in tissues. The results showed that beta-Gal activity was significantly increased by 38% in lung around bronchioles when inhalation with PM and 10% ethanol was given. The 10% ethanol also increased the intracellular apparent permeability by 42% in stomach and by 141% in intestine at 48 h after the first dosage of delivery. Also delivery of DNA encoding a functional human cystic fibrosis transmembrane protein (CFTR) using the same inhalation delivery method co-formulated with 10% ethanol, an increased expression of CFTR in lung was detected by immunostaining. We concluded that 10% ethanol co-formulated with the PM system could enhance inhaled gene delivery to airway and gastrointestinal (GI) tract. PMID:17258837

  16. Adverse reactions to intravenous iodinated contrast media: a primer for radiologists.


    Namasivayam, Saravanan; Kalra, Mannudeep K; Torres, William E; Small, William C


    Adverse reactions to intravenous iodinated contrast media may be classified as general and organ-specific, such as contrast-induced nephrotoxicity. General adverse reactions may be subclassified into acute and delayed types. Acute general adverse reactions can range from transient minor reactions to life-threatening severe reactions. Non-ionic contrast media have lower risk of mild and moderate adverse reactions. However, the risk of fatal reactions is similar for ionic and non-ionic contrast media. Adequate preprocedure evaluation should be performed to identify predisposing risk factors. Prompt recognition and treatment of acute adverse reactions is crucial. Risk of contrast induced nephrotoxicity can be reduced by use of non-ionic contrast media, less volume of contrast, and adequate hydration. The radiologist can play a pivotal role by being aware of predisposing factors, clinical presentation, and management of adverse reactions to contrast media. PMID:16688432

  17. Biosorption of water-soluble dyes on magnetically modified Saccharomyces cerevisiae subsp. uvarum cells.


    Safaríková, M; Ptácková, L; Kibriková, I; Safarík, I


    Brewer's yeast (bottom yeast, Saccharomyces cerevisiae subsp. uvarum) cells were magnetically modified using water based magnetic fluid stabilized with perchloric acid. Magnetically modified yeast cells efficiently adsorbed various water soluble dyes. The dyes adsorption can be described by the Langmuir adsorption model. The maximum adsorption capacity of the magnetic cells differed substantially for individual dyes; the highest value was found for aniline blue (approx. 220 mg per g of dried magnetic adsorbent). PMID:15811411

  18. The removal of kaolinite suspensions by acid-soluble and water-soluble chitosans.


    Chung, Ying-Chien; Wu, Li-Chun; Chen, Chih-Yu


    Chitosan is a potential substitute for traditional aluminium salts in water treatment systems. This research compared the coagulant performance of acid-soluble chitosan with water-soluble chitosan and with coagulant mixtures of chitosan and aluminium sulfate (alum). We also assessed the coagulant performance of chitosan and poly-aluminium chloride (PAC) to remove kaolinite from turbid water. In addition, we evaluated their respective coagulation efficiencies under different coagulant concentrations, degrees of turbidity (NTU) and pH levels. Furthermore, we determined the size and settling velocity of flocs formed by these coagulants in order to illustrate major factors affecting kaolinite coagulation. The optimal concentrations of acid- versus water- soluble chitosan required to remove kaolinite from a 300 NTU suspension were 4.0 and 10.0 mg/l, respectively-with individual efficiencies of 79.3 and 92.4%, in that order. Optimum concentrations ofwater-soluble chitosan demonstrated a broader range than that of acid-soluble chitosan. In addition, it is of note that chitosan/alum and chitosan/PAC water-soluble coagulant mixtures demonstrated much wider ranges of optimal concentrations for turbidity reduction than either alum or PAC alone. Moreover, our water-soluble chitosan coagulant mixtures produced denser floc with elevated settling velocities that favour cost savings relevant to both installation and operational expenses. Based on our observations of these noteworthy performances, we confidently propose that a coagulant mixture with a 1:1 mass ratio of chitosan and alum presents a remarkably more cost-effective alternative to the use of chitosan alone in water treatment systems. PMID:23530342

  19. NASA Workmanship Hot Topics: Water Soluble Flux and ESD Charge Device Model

    NASA Technical Reports Server (NTRS)

    Plante, Jeannette F.


    This slide presentation reviews two topics of interest to NASA Workmanship: (1) Water Soluble Flux (WSF) and Electrostatic Discharge (ESD) safety. In the first topic, WSF, the presentation reviews voiding and the importance of cleanliness in using WSF for welding and soldering operations. The second topic reviews the NASA-HDBK-8739.21 for Human Body Model, and Machine Model safety methods, and challenges associated with the Charged Device Model (CDM)

  20. Biosynthetic Studies on Water-Soluble Derivative 5c (DTX5c)

    PubMed Central

    Vilches, Tamara S.; Norte, Manuel; Daranas, Antonio Hernández; Fernández, José J.


    The dinoflagellate Prorocentrum belizeanum is responsible for the production of several toxins involved in the red tide phenomenon known as Diarrhetic Shellfish Poisoning (DSP). In this paper we report on the biosynthetic origin of an okadaic acid water-soluble ester derivative, DTX5c, on the basis of the spectroscopical analysis of 13C enriched samples obtained by addition of labelled sodium [l-13C], [2-13C] acetate to artificial cultures of this dinoflagellate. PMID:23170080

  1. High Throughput Identification, Purification and Structural Characterization of Water Soluble Protein Complexes in Desulfovibrio vulgaris

    SciTech Connect

    Dong,, Ming; Han, Bong-Gyoon; Liu, Hui-Hai; Malik, J.; Geller, Jil; Yang, Li; Choi, M.; Chandonia, John-Marc; Arbelaez, Pablo; Sterling, H. J.; Typke, Dieter; Shatsky, Max; Brenner, Steve; Fisher, Susan; Williams, Evan; Szakal, Evelin; Allen, S.; Hall, S. C.; Hazen, Terry; Witkowska, H. E.; Jin, Jiming; Glaeser, Robert; Biggin, Mark


    Our scheme for the tagless purification of water soluble complexes. 10 g of protein from a crude bacterial extract is first fractionated by ammonium sulfate precipitation and then by a series of chromatographic steps: anion exchange (IEX), hydrophobic interaction (HIC), and finally size exclusion (Gel Filtration). Fractions from the last chromatography step are trypsin digested and peptides labeled with iTRAQ reagents to allow multiplexing and quantitation during mass spectrometric analysis. Elution profiles of identified proteins are then subjected to clustering analysis.

  2. Synthesis of Water-Soluble, Thiolate-Protected Gold Nanoparticles Uniform in Size.


    Azubel, Maia; Kornberg, Roger D


    By a modification of the method of Brust et al., water-soluble, thiolate-protected gold nanoparticles that are uniform in size were synthesized with no requirement for purification. The modification of the method was equilibration in the first step, which proved crucial for achieving size homogeneity. The thiol-to-gold ratio controlled the size of the particles, and the choice of thiol controlled the reactivity of the particles toward thiol exchange. PMID:27042759

  3. Water Solubility Studies in Lower Mantle Perovskite by Fourier Transform Infrared Spectroscopy

    NASA Astrophysics Data System (ADS)

    Amulele, G.; Otsuka, K.; Sanchez, C.; Lee, K. K.; Karato, S.; Liu, Z.; Chen, Z.


    Although the water solubility in lower mantle minerals is critical for understanding of global water circulation, the water solubility in lower mantle minerals is poorly constrained. The water solubility in MgSiO3-perovskite as well as Al-bearing MgSiO3-perovskite synthesized at 1500 - 1600 K and 24 - 25 GPa under SiO2 or MgO saturated conditions have been investigated by FTIR spectroscopy both at ambient as well as modest pressures of up to 10 GPa in a diamond-anvil cell using KBr as a pressure medium. The FTIR spectra show one dominant band at 3440 cm-1 in MgSiO3-perovskite corresponding to about 50 - 70 ppm wt water in the perovskite. This is consistent with the results by Litasov et al. (2003) who obtained solubility of about 100 ppm wt water in MgSiO3-perovskite, but much larger than the values reported by Bolfan-Casanova et al. (2000). Based on the in-situ FTIR in a diamond-anvil cell using KCl as a pressure medium, Reid et al. (2006) reported infrared absorption peaks at 3160 and 3066 cm-1 at high pressures that broaden and weaken at low (<3 GPa) pressures. They interpreted that these peak are caused by unquenchable hydroxyl-related species. However, we did not find these peaks but instead we found these peaks from the FTIR spectroscopy of KCl. We conclude that 3160 and 3060 cm-1 peaks are due to KCl, and MgSiO3 perovskite has small but finite water solubility (~50-70 ppm wt) that is expected to increase with Al content. We also present corresponding high-pressure x-ray diffraction measurements on the nominally hydrous MgSiO3-perovskite carried out up to 30 GPa.

  4. Formamide: an efficient solvent to synthesize water-soluble and sub-ten-nanometer nanocrystals

    NASA Astrophysics Data System (ADS)

    Xu, Biao; Zhang, Zhicheng; Wang, Xun


    Nanocrystals have drawn lots of attention in many fields. The main-stream synthetic routes usually produced hydrophobic nanocrystals (NCs). Organometallic precursors and long-alkyl-chain ligands are adopted and for further use surface modification to render them water-soluble is needed. A direct protocol to synthesize water-soluble NCs in an environmental-friendly and convenient way is still quite deficient, especially for sub-10 nm NCs. We report here a formamide solvent-system to prepare high-quality metal, metal alloy, metal sulfide, metal selenide and ternary sulfide NCs in the sub-10 nm region, with simple inorganic metal salts as precursors. The as-obtained NCs exhibit monodisperse size and can be dispersed in aqueous solution for further applications.Nanocrystals have drawn lots of attention in many fields. The main-stream synthetic routes usually produced hydrophobic nanocrystals (NCs). Organometallic precursors and long-alkyl-chain ligands are adopted and for further use surface modification to render them water-soluble is needed. A direct protocol to synthesize water-soluble NCs in an environmental-friendly and convenient way is still quite deficient, especially for sub-10 nm NCs. We report here a formamide solvent-system to prepare high-quality metal, metal alloy, metal sulfide, metal selenide and ternary sulfide NCs in the sub-10 nm region, with simple inorganic metal salts as precursors. The as-obtained NCs exhibit monodisperse size and can be dispersed in aqueous solution for further applications. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr00643c

  5. Enhanced water-solubility, antibacterial activity and biocompatibility upon introducing sulfobetaine and quaternary ammonium to chitosan.


    Chen, Yuxiang; Li, Jianna; Li, Qingqing; Shen, Yuanyuan; Ge, Zaochuan; Zhang, Wenwen; Chen, Shiguo


    Chitosan (CS) has attracted much attention due to its good antibacterial activity and biocompatibility. However, CS is insoluble in neutral and alkaline aqueous solution, limiting its biomedical application to some extent. To circumvent this drawback, we have synthesized a novel N-quaternary ammonium-O-sulfobetaine-chitosan (Q3BCS) by introducing quaternary ammonium compound (QAC) and sulfobetaine, and its water-solubility, antibacterial activity and biocompatibility were evaluated compare to N-quaternary ammonium chitosan and native CS. The results showed that by introducing QAC, antibacterial activities and water-solubilities increase with degrees of substitution. The largest diameter zone of inhibition (DIZ) was improved from 0 (CS) to 15mm (N-Q3CS). And the water solution became completely transparent from pH 6.5 to pH 11; the maximal waters-solubility was improved from almost 0% (CS) to 113% at pH 7 (N-Q3CS). More importantly, by further introducing sulfobetaine, cell survival rate of Q3BCS increased from 30% (N-Q3CS) to 85% at 2000μg/ml, which is even greater than that of native CS. Furthermore, hemolysis of Q3BCS was dropped sharply from 4.07% (N-Q3CS) to 0.06%, while the water-solution and antibacterial activity were further improved significantly. This work proposes an efficient strategy to prepare CS derivatives with enhanced antibacterial activity, biocompatibility and water-solubility. Additionally, these properties can be finely tailored by changing the feed ratio of CS, glycidyl trimethylammonium chloride and NCO-sulfobetaine. PMID:27083366

  6. Quinlobelane: A water-soluble lobelane analogue and inhibitor of VMAT2

    PubMed Central

    Vartak, Ashish P.; Deaciuc, A. Gabriela; Dwoskin, Linda P.; Crooks, Peter A.


    Replacing the phenyl groups in the structure of the VMAT2 inhibitor, lobelane with either pyridyl, quinolyl or indolyl groups affords novel analogues with improved water solubility. The synthetic methodologies reported herein also underscore the paucity of hydrogenation methods that offer selectivity in the synthesis of the different classes of heteroaromatic lobelane analogues. The quinolyl group was the only replacement for the phenyl group in lobelane that retained VMAT2 inhibition. PMID:20494575

  7. Water-soluble and biocompatible MnO@PVP nanoparticles for MR imaging in vitro and in vivo.


    Hu, Xiaoqing; Ji, Yuxuan; Wang, Mingliang; Miao, Fei; Ma, Hongmei; Shen, Hebai; Jia, Nengqin


    The uniform-sized manganese oxide nanoparticles (the oleic-capped MnO NPs) were synthesized by the thermal decomposition of Mn-oleate complex and were transferred into water with the help of cationic surfactant of cetyltrimethyl ammonium bromide (CTAB), then the poly(vinylpyrrolidone) (PVP) membrane was further coated on to them with the aid of anionic dispersant of poly(styrenesulfonate) (PSS) by layer-by-layer electrostatic assembly to render them water soluble and biocompatible. They were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), X-ray diffraction (XRD), Fourier-transform infrared (FTIR) and MTT assay. In vitro cellular uptake test revealed the MnO@PVP NPs were low cytotoxic, biocompatible and could be used as a T,-positive contrast agent for passive targeting magnetic resonance imaging (MRI). Interestingly, signal enhancement in cerebral spinal fluid (CSF) spaces in vivo experiment suggested that the MnO@PVP NPs can pass through the blood brain barrier (BBB). These results show that MnO@PVP NPs are good candidates as MRI contrast agents with the lack of cytotoxicity and have great potential applications in magnetic nano-device and biomagnetic field. PMID:23858961

  8. Synthesis of water soluble glycine capped silver nanoparticles and their surface selective interaction

    SciTech Connect

    Agasti, Nityananda; Singh, Vinay K.; Kaushik, N.K.


    Highlights: • Synthesis of water soluble silver nanoparticles at ambient reaction conditions. • Glycine as stabilizing agent for silver nanoparticles. • Surface selective interaction of glycine with silver nanoparticles. • Glycine concentration influences crystalinity and optical property of silver nanoparticles. - Abstract: Synthesis of biocompatible metal nanoparticles has been an area of significant interest because of their wide range of applications. In the present study, we have successfully synthesized water soluble silver nanoparticles assisted by small amino acid glycine. The method is primarily based on reduction of AgNO{sub 3} with NaBH{sub 4} in aqueous solution under atmospheric air in the presence of glycine. UV–vis spectroscopy, transmission electron microscopy (TEM), X–ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetry (TG) and differential thermal analysis (DTA) techniques used for characterization of resulting silver nanoparticles demonstrated that, glycine is an effective capping agent to stabilize silver nanoparticles. Surface selective interaction of glycine on (1 1 1) face of silver nanoparticles has been investigated. The optical property and crystalline behavior of silver nanoparticles were found to be sensitive to concentration of glycine. X–ray diffraction studies ascertained the phase specific interaction of glycine on silver nanoparticles. Silver nanoparticles synthesized were of diameter 60 nm. We thus demonstrated an efficient synthetic method for synthesis of water soluble silver nanoparticles capped by amino acid under mild reaction conditions with excellent reproducibility.

  9. Abalone water-soluble matrix for self-healing biomineralization of tooth defects.


    Wen, Zhenliang; Chen, Jingdi; Wang, Hailiang; Zhong, Shengnan; Hu, Yimin; Wang, Zhili; Zhang, Qiqing


    Enamel cannot heal by itself if damaged. Hydroxyapatite (HAP) is main component of human enamel. Formation of enamel-like materials for healing enamel defects remains a challenge. In this paper, we successfully isolated the abalone water-soluble matrix (AWSM) with 1.53wt% the abalone water-soluble protein (AWSPro) and 2.04wt% the abalone water-soluble polysaccharide (AWSPs) from abandoned abalone shell, and self-healing biomineralization of tooth defects was successfully achieved in vitro. Based on X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), hot field emission scanning electron microscopy (HFESEM) and energy dispersive spectrometer (EDS) analysis, the results showed that the AWSM can efficiently induce remineralization of HAP. The enamel-like HAP was successfully achieved onto etched enamel's surface due to the presence of the AWSM. Moreover, the remineralized effect of eroded enamel was growing with the increase of the AWSM. This study provides a solution to the resource waste and environmental pollution caused by abandoned abalone shell, and we provides a new method for self-healing remineralization of enamel defects by AWSM and develops a novel dental material for potential clinical dentistry application. PMID:27287112

  10. Determination of water-soluble forms of oxalic and formic acids in soils by ion chromatography

    NASA Astrophysics Data System (ADS)

    Karicheva, E.; Guseva, N.; Kambalina, M.


    Carboxylic acids (CA) play an important role in the chemical composition origin of soils and migration of elements. The content of these acids and their salts is one of the important characteristics for agrochemical, ecological, ameliorative and hygienic assessment of soils. The aim of the article is to determine water-soluble forms of same carboxylic acids — (oxalic and formic acids) in soils by ion chromatography with gradient elution. For the separation and determination of water-soluble carboxylic acids we used reagent-free gradient elution ion-exchange chromatography ICS-2000 (Dionex, USA), the model solutions of oxalate and formate ions, and leachates from soils of the Kola Peninsula. The optimal gradient program was established for separation and detection of oxalate and formate ions in water solutions by ion chromatography. A stability indicating method was developed for the simultaneous determination of water-soluble organic acids in soils. The method has shown high detection limits such as 0.03 mg/L for oxalate ion and 0.02 mg/L for formate ion. High signal reproducibility was achieved in wide range of intensities which correspond to the following ion concentrations: from 0.04 mg/g to 10 mg/L (formate), from 0.1 mg/g to 25 mg/L (oxalate). The concentration of formate and oxalate ions in soil samples is from 0.04 to 0.9 mg/L and 0.45 to 17 mg/L respectively.

  11. Water solubility measurements in supercritical fluids and high-pressure liquids using near-infrared spectroscopy

    SciTech Connect

    Jackson, K.; Bowman, L.E.; Fulton, J.L.


    A small amount of water added to a supercritical fluid can greatly increase the solubility of polar species in nonpolar fluids. These modified supercritical solutions significantly expand the use of the fluids in separations and reactions. In order to successfully utilize these systems, information on the miscibility or solubility of water in the fluid is required. Often solubility data are not available for water in a supercritical fluid under a given set of temperature and pressure conditions, and a costly set of equipment must be assembled in order to make these measurements. A relatively fast and inexpensive technique to measure water solubilities using a simple long path length optical cell in an FT-IR spectrometer is described. This technique is also applicable to common and newly developed refrigerants where water solubilities are often unknown at temperatures much above ambient. In this paper, water solubility data in carbon dioxide and two types of refrigerants (chlorodifluoromethane, R22; 1,1,1,2-tetrafluoroethane, R134a) are presented for temperatures from approximately 40 to 110{degree}C and pressures from approximately 10 to 344.8 bar. 26 refs., 6 figs., 4 tabs.

  12. Synthesis of Water Soluble Camptothecin-Polyoxetane Conjugates via Click Chemistry

    PubMed Central

    Zolotarskaya, Olga Yu.; Wagner, Alison F.; Beckta, Jason M.; Valerie, Kristoffer; Wynne, Kenneth J.; Yang, Hu


    Water soluble camptothecin (CPT)-polyoxetane conjugates were synthesized using a clickable polymeric platform P(EAMO) that was made by polymerization of acetylene-functionalized 3-ethyl-3-hydroxymethyl oxetane (i.e., EAMO). CPT was first modified with a linker 6-azidohexanoic acid via an ester linkage to yield CPT-azide. CPT-azide was then click coupled to P(EAMO) in dichloromethane using bromotris(triphenylphosphine) copper(I)/N,N-diisopropylethylamine. For water solubility and cytocompatibility improvement, methoxypolyethylene glycol azide (mPEG-azide) was synthesized from mPEG 750 gmol−1 and click grafted using copper(II) sulfate and sodium ascorbate to P(EAMO)-g-CPT. 1H NMR spectroscopy confirmed synthesis of all intermediates and the final product P(EAMO)-g-CPT/PEG. CPT was found to retain its therapeutically active lactone form. The resulting P(EAMO)-g-CPT/PEG conjugates were water soluble and produced dose-dependent cytotoxicity to human glioma cells and increased γ-H2AX foci formation, indicating extensive cell cycle-dependent DNA damage. Altogether, we have synthesized CPT-polymer conjugates able to induce controlled toxicity to human cancer cells. PMID:23051100

  13. Dendrimer-curcumin conjugate: a water soluble and effective cytotoxic agent against breast cancer cell lines.


    Debnath, Shawon; Saloum, Darin; Dolai, Sukanta; Sun, Chong; Averick, Saadyah; Raja, Krishnaswami; Fata, Jimmie E


    Curcumin, which is derived from the plant Curcuma longa, has received considerable attention as a possible anti-cancer agent. In cell culture, curcumin is capable of inducing apoptosis in cancer cells at concentrations that do not affect normal cells. One draw-back holding curcumin back from being an effective anti-cancer agent in humans is that it is almost completely insoluble in water and therefore has poor absorption and subsequently poor bioavailability. Here we have generated a number of curcumin derivatives (tetrahydro-curcumin, curcumin mono-carboxylic acid, curcumin mono-galactose, curcumin mono-alkyne and dendrimer-curcumin conjugate) to test whether any of them display both cytotoxicity and water solubility. Of those tested only dendrimer-curcumin conjugate exhibited both water solubility and cytotoxicity against SKBr3 and BT549 breast cancer cells. When compared to curcumin dissolved in DMSO, dendrimer-curcumin conjugate dissolved in water was significantly more effective in inducing cytotoxicity, as measured by the MTT assay and effectively induced cellular apoptosis measured by caspase-3 activation. Since dendrimer-curcumin conjugate is water soluble and capable of inducing potent cytotoxic effects on breast cancer cell lines, it may prove to be an effective anti-cancer therapy to be used in humans. PMID:23387971

  14. Chlorin p6-Based Water-Soluble Amino Acid Derivatives as Potent Photosensitizers for Photodynamic Therapy.


    Meng, Zhi; Yu, Bin; Han, Guiyan; Liu, Minghui; Shan, Bin; Dong, Guoqiang; Miao, Zhenyuan; Jia, Ningyang; Tan, Zou; Li, Buhong; Zhang, Wannian; Zhu, Haiying; Sheng, Chunquan; Yao, Jianzhong


    The development of novel photosensitizer with high phototoxicity, low dark toxicity, and good water solubility is a challenging task for photodynamic therapy (PDT). A series of chlorin p6-based water-soluble amino acid conjugates were synthesized and investigated for antitumor activity. Among them, aspartylchlorin p6 dimethylester (7b) showed highest phototoxicity against melanoma cells with weakest dark toxicity, which was more phototoxic than verteporfin while with less dark toxicity. It also exhibited better in vivo PDT antitumor efficacy on mice bearing B16-F10 tumor than verteporfin. The biological assays revealed that 7b was localized in multiple subcellular organelles and could cause both cell necrosis and apoptosis after PDT in a dose-dependent manner, resulting in more effective cell destruction. As a result, 7b represents a promising photosensitizer for PDT applications because of its strong absorption in the phototherapeutic window, relatively high singlet oxygen quantum yield, highest dark toxicity/phototoxicity ratio, good water solubility, and excellent in vivo PDT antitumor efficacy. PMID:27136389

  15. Biodesulfurization of water-soluble coal-derived material by Rhodococcus rhodochrous IGTS8

    SciTech Connect

    Kilbane, J.J. II; Jackowski, K.


    Rhodococcus rhodochrous IGTS8 was previously isolated because of its ability to use coal as its sole source of sulfur for growth. Subsequent growth studies have revealed that IGTS8 is capable of using a variety of organosulfur compounds as sources of sulfur but not carbon. In this paper, the ability of IGTS8 to selectively remove organic sulfur from water-soluble coal-derived material is investigated. The microbial removal of organic sulfur from coal requires microorganisms capable of cleaving carbonsulfur bonds and the accessibility of these bonds to microorganisms. The use of water-soluble coal-derived material effectively overcomes the problem of accessibility and allows the ability of microorganisms to cleave carbonsulfur bonds present in coal-derived material to be assessed directly. Three coals, two coal solubilization procedures, and two methods of biodesulfurization were examined. The results of these experiments reveal that the microbial removal of significant amounts of organic sulfur from watersoluble coal-derived material with treatment times as brief as 24 hours is possible. Moreover, the carbon content and calorific value of biotreated products are largely unaffected. Biotreatment does, however, result in increases in the hydrogen and nitrogen content and a decreased oxygen content of the coal-derived material. The aqueous supernatant obtained from biodesulfurization experiments does not contain sulfate, sulfite, or other forms of soluble sulfur at increased concentrations in comparison with control samples. Sulfur removed from water-soluble coal-derived material appears to be incorporated into biomass.

  16. Synthesis of water soluble glycosides of pentacyclic dihydroxytriterpene carboxylic acids as inhibitors of α-glucosidase.


    Xu, Jiancong; Nie, Xuliang; Hong, Yanping; Jiang, Yan; Wu, Guoqiang; Yin, Xiaoli; Wang, Chunrong; Wang, Xiaoqiang


    A series of compounds were synthesized by glycosylation of maslinic acid (MA) and corosolic acid (CA) with monosaccharides and disaccharides, and the structures of the derivatives were elucidated by standard spectroscopic methods including (1)H NMR, (13)C NMR and HRMS. The α-glucosidase inhibitory activities of all the novel compounds were evaluated in vitro. The solubility and inhibitory activity of α-glucosidase assays showed that the bis-disaccharide glycosides of triterpene acids possessed higher water solubility and α-glucosidase inhibitory activities than the bis-monosaccharide glycosides. Among these compounds, maslinic acid bis-lactoside (8e, IC50 = 684 µM) and corosolic acid bis-lactoside (9e, IC50 = 428 µM) had the best water solubility, and 9e exhibited a better inhibitory activity than acarbose (IC50 = 478 µM). However, most of glycosylated derivatives possessed lower inhibitory activities than the parent compounds, although their water solubility was enhanced obviously. Moreover, the kinetic inhibition studies indicated that 9e was a non-competitive inhibitor, and structure-activity relationships of the derivatives are also discussed. PMID:26974355

  17. The water-soluble fraction of carbon, sulfur, and crustal elements in Asian aerosols and Asian soils

    NASA Astrophysics Data System (ADS)

    Duvall, R. M.; Majestic, B. J.; Shafer, M. M.; Chuang, P. Y.; Simoneit, B. R. T.; Schauer, J. J.

    We quantified the water-soluble species in 24 h average TSP (Dunhuang and Gosan) and PM1.0 (Gosan only) samples associated with the Spring 2001 Asian Dust season. Samples were analyzed for water-soluble organic carbon, water-soluble sulfur, and water-soluble crustal elements, as well as their bulk chemical composition. Water-soluble organic carbon in Gosan accounted for 28-83% (average=63%) of the particle-phase TSP total organic carbon, and 1-69% (average=23%) of the particle-phase PM1.0 organic carbon. Water-soluble sulfur, primarily in the form of sulfate, accounted for 2-22% of the TSP mass in Gosan, and 0.9-11% of the TSP mass in Dunhuang. The absolute concentrations and the soluble fraction of crustal elements in TSP samples collected at Gosan were found to correlate with the air mass source region as determined by back-trajectory analysis. For example, elevated levels of water-soluble sodium, potassium, and calcium were observed during dust events. These observations are likely the result of differences in anthropogenic sources, mineralogical composition of resuspended crustal materials, and atmospheric processing of the aerosols. Experiments were conducted using Asian soil samples to study the impact of acidification by nitric acid vapor on the solubility of crustal elements present in Asian desert and non-desert dusts. These experiments demonstrated that gaseous nitric acid attack leads to significant increases (>100% increase) in water-soluble calcium, magnesium, aluminum, manganese, and iron, while little or no increases in water-soluble sodium and potassium were observed in the soils.

  18. Silica gel as a particulate carrier of poorly water-soluble substances in aquatic toxicity testing.


    Breitholtz, Magnus; Ricklund, Niklas; Bengtsson, Bengt-Erik; Persson, N Johan


    Aquatic toxicity tests were originally developed for water-soluble substances. However, many substances are hydrophobic and thus poorly water-soluble, resulting in at least two major implications. Firstly, toxicity may not be reached within the range of water solubility of the tested compound(s), which may result in the formation of solids or droplets of the tested substance and consequently an uneven exposure. Secondly, because of multi-phase distribution of the tested substance it may be complicated to keep exposure concentrations constant. To overcome such problems, we have introduced silica gel as a particulate carrier in a toxicity test with the benthic copepod Nitocra spinipes. The main objective of the current study was to evaluate whether a controlled exposure could be achieved with the help of silica gel for testing single poorly water-soluble substances. A secondary objective was to evaluate whether an equilibrium mass balance model could predict internal concentrations that were consistent with the toxicity data and measured internal concentrations of two model hydrophobic substances, i.e., the polybrominated diphenyl ethers BDE-47 and BDE-99. Larval N. spinipes were exposed for 6 days to BDE-47 and BDE-99, respectively, in the silica gel test system and, for comparative reasons, in a similar and more traditional semi-static water test system. Via single initial amounts of the model substances administered on the silica gel, effects on both larval development and mortality resulted in higher and more concentration-related toxicity than in the water test system. We conclude that the silica gel test system enables a more controlled exposure of poorly water-soluble substances than the traditional water test system since the concentration-response relationship becomes distinct and there is no carrier solvent present during testing. Also, the single amount of added substance given in the silica gel test system limits the artefacts (e.g., increased chemical

  19. Effects of some non-ionic surfactants on transepithelial permeability in Caco-2 cells.


    Dimitrijevic, D; Shaw, A J; Florence, A T


    The effects of the non-ionic surfactants polysorbate 20, polysorbate 60, polysorbate 85, cholesteryl poly (24) oxyethylene ether (Solulan C24) and the lanolin-based poly (16) oxyethylene ether (Solulan 16) on the epithelial integrity of monolayers of human intestinal epithelial (Caco-2) cells has been studied using metformin as a model drug. The aim was to identify the surfactants and their optimal concentrations capable of enhancing drug transport while causing no, or only minor, cellular damage. Effects on cell permeability were assessed by measurements of the transport of metformin, a hydrophilic drug, by monitoring transepithelial electrical resistance. Cell viability was determined by the diphenyltetrazolium bromide test (the MTT test). All the surfactants studied demonstrated concentration-dependent effects on cell permeability and cell viability. The effects on transepithelial electrical resistance correlated with cell viability, i.e. increased transepithelial electrical resistance and increased cell-monolayer permeability for metformin corresponded to decreased cell viability. The results indicate that the Solulan and polysorbate surfactants were active as absorption enhancers, Solulan C24 and 16 being more effective than polysorbates 20, 60 or 85, causing an increase in metformin transport at lower concentrations than the polysorbates. Polysorbate 20 exerted its greatest effect at a concentration of 5%-increasing the flux of metformin after 3 h by a factor of around 20 over the control. Large increases in the transport of metformin, especially at surfactant levels of 0.05%, 0.1% and 0.5%, were related to the effect of Solulan C24 and Solulan 16 on the cell permeability. The Caco-2 cell monolayer experiments confirmed the ability, especially of polysorbate 20, Solulan C24 and Solulan 16, to increase the absorption of metformin. The polysorbates increased permeability as a result of solubilisation of membrane components, while Solulans did so by penetrating

  20. Structure, thermodynamics and dynamics of the isotropic phase of spherical non-ionic surfactant micelles.


    Tse-Ve-Koon, Kévin; Tremblay, Nicolas; Constantin, Doru; Freyssingeas, Éric


    We investigate a non-ionic surfactant (C(12)E(8))/water binary mixture, over a wide range of concentrations and temperatures (i.e. 1-35 wt.% of C(12)E(8) and 10-60 °C in temperature) by means of different experimental techniques: Small-Angle Neutron Scattering (SANS), Quasi Elastic Light Scattering (QELS) and High Frequency Rheology. The aims of this work are to provide information on structure, thermodynamics and dynamics of the isotropic phase of such a micellar system and, by combining these different types of information, to obtain a comprehensive image of the behaviour of this phase. Our results demonstrate that structural, thermodynamic and dynamic properties of these solutions are fully monitored by the temperature-induced changes in the ethylene-glycol chain hydration. They confirm that C(12)E(8) micelles are spherical and do not grow in the investigated range of concentrations and temperatures. They demonstrate that the interaction potential between C(12)E(8) micelles is more complicated than what was previously described, with an additional repulsive interaction. They allow us to put forward explanations for the Isotropic-Ordered phase transition as well as for the temperature behaviour of the viscosity of C(12)E(8) micellar solutions. Our investigation provides new and valuable information on the dynamics of these mixtures that reflect the complexity of the interaction potential between the C(12)E(8) micelles. It shows that concentrated solutions exhibit a viscoelastic behaviour that can be described by a simple Maxwell model. PMID:23201065

  1. Self-assembly in aqueous solutions of a non-ionic hydrotrope

    NASA Astrophysics Data System (ADS)

    Subramanian, Deepa

    Hydrotropes are amphiphilic molecules, too small to cause spontaneous self-assembly towards equilibrium mesoscale structures in aqueous solutions, but they form dynamic, noncovalent assemblies, which may create microscopic regions of lowered polarity. This enhances the solubilization of hydrophobic compounds, also known as solubilizates, in aqueous solutions and may cause further aggregation to larger structures. In this work, unusual mesoscopic properties of aqueous solutions of a non-ionic hydrotrope, namely tertiary butyl alcohol (TBA) have been investigated by light scattering, microscopy, and chromatography. Aqueous TBA solutions show anomalous thermodynamic and structural properties in the range of concentrations 3-8 mol % TBA and temperatures 0-25 °C. These anomalies appear to be associated with short-lived, short-ranged micelle-like structural fluctuations, distinctly different from usual concentration fluctuations in non-ideal solutions. Molecular dynamics simulations and neutron-scattering experiments show clustering of TBA molecules on a nanometer scale, interacting through hydrogen bonds with a shell of water molecules. In this concentration range, TBA aqueous solutions, although macroscopically homogeneous, occasionally show the presence of "mysterious" inhomogeneities on a 100 nm scale. We have found that the emergence of such inhomogeneities strongly correlates with impurities present in commercial TBA samples. Experiments with controlled addition of a third component, such as propylene oxide, isobutyl alcohol, or cyclohexane, reveal the mechanism of formation of these inhomogeneities through stabilization of micelle-like fluctuations by a solubilizate. These structures are long-lived, i.e., stable from a few days up to many months. We have confirmed that mesoscale structures in aqueous solutions can be generated from self-assembly of small molecules, without involvement of surfactants or polymers. This kind of self-assembly may potentially result

  2. Characterization of the size-segregated water-soluble inorganic ions in the Jing-Jin-Ji urban agglomeration: Spatial/temporal variability, size distribution and sources

    NASA Astrophysics Data System (ADS)

    Li, Xingru; Wang, Lili; Ji, Dongsheng; Wen, Tianxue; Pan, Yuepeng; Sun, Ying; Wang, Yuesi


    To investigate the characteristics of aerosols in north China, the samples of water-soluble ions, including anions (F-, Cl-, NO2-, NO3-, SO42-) and cations (NH4+, K+, Na+, Ca2+, Mg2+) in 8 size-segregated particle fractions, are collected using a sampler from Sep. 2009 to Aug. 2010 at four sites in urban areas (Beijing, Tianjin and Tangshan) and a background region (Xinglong) in the Jing-Jin-Ji urban agglomeration. High spatial variability is observed between the urban areas and the background region. The results of chemical composition analysis showed that secondary water soluble ions (SO42- + NO3- + NH4+) (SWSI) composed more than half the total ions, and are mainly found in fine particles (aerodynamic diameters less than 2.1 μm), while Mg2+ and Ca2+ contributed to a large fraction of the total water-soluble ions in coarse particles (aerodynamic diameters greater than 2.1 μm and less than 9.0 μm). The concentrations of SO42-, NO3- and NH4+ are higher in summer and winter and lower in spring and autumn. Mg2+ and Ca2+ are obviously abundant in winter in Beijing, Tianjin and Tangshan. In contrast, Mg2+ and Ca2+ are abundant in autumn in Xinglong. The SWSI showed a bimodal size distribution with the fine mode at 0.43-1.1 μm and the coarse mode at 4.7-5.8 μm, and had different seasonal variations and bimodal shapes. NH4+ played an important role in the size distributions and the formations of SO42- and NO3-. Heterogeneous reaction is the main formation mechanism of SO42- and NO3-, which tended to be enriched in the coarse mode of aerosol. The sulfur oxidation ratio (SOR) and nitrogen oxidation ratio (NOR) indicated high photochemical oxidation property over the whole Jing-Jin-Ji urban agglomeration.

  3. Water-soluble noncovalent adducts of the heterometallic copper subgroup complexes and human serum albumin with remarkable luminescent properties.


    Chelushkin, P S; Krupenya, D V; Tseng, Yu-Jui; Kuo, Ting-Yi; Chou, Pi-Tai; Koshevoy, I O; Burov, S V; Tunik, S P


    Novel water-soluble noncovalent adducts of the heterometallic copper subgroup complexes and human serum albumin (HSA) display strong phosphorescence, internalize into HeLa cells and can be used in time-resolved fluorescent imaging. PMID:24296768

  4. Microautoradiography of Water-Soluble Compounds in Plant Tissue after Freeze-Drying and Pressure Infiltration with Epoxy Resin

    PubMed Central

    Vogelmann, Thomas C.; Dickson, Richard E.


    It is difficult to retain and localize radioactive, water-soluble compounds within plant cells. Existing techniques retain water-soluble compounds with varying rates of efficiency and are limited to processing only a few samples at one time. We developed a modified pressure infiltration technique for the preparation of microautoradiographs of 14C-labeled, water-soluble compounds in plant tissue. Samples from cottonwood (Populus deltoides Bartr. ex Marsh.) labeled with 14C were excised, quick frozen in liquid N2, freeze-dried at −50°C, and pressure-infiltrated with epoxy resin without intermediate solvents or prolonged incubation times. The technique facilitates the mass processing of samples for microautoradiography, gives good cellular retention of labeled water-soluble compounds, and is highly reproducible. Images Fig. 2 PMID:16662542

  5. Water-soluble LYNX1 Residues Important for Interaction with Muscle-type and/or Neuronal Nicotinic Receptors*

    PubMed Central

    Lyukmanova, Ekaterina N.; Shulepko, Mikhail A.; Buldakova, Svetlana L.; Kasheverov, Igor E.; Shenkarev, Zakhar O.; Reshetnikov, Roman V.; Filkin, Sergey Y.; Kudryavtsev, Denis S.; Ojomoko, Lucy O.; Kryukova, Elena V.; Dolgikh, Dmitry A.; Kirpichnikov, Mikhail P.; Bregestovski, Piotr D.; Tsetlin, Victor I.


    Human LYNX1, belonging to the Ly6/neurotoxin family of three-finger proteins, is membrane-tethered with a glycosylphosphatidylinositol anchor and modulates the activity of nicotinic acetylcholine receptors (nAChR). Recent preparation of LYNX1 as an individual protein in the form of water-soluble domain lacking glycosylphosphatidylinositol anchor (ws-LYNX1; Lyukmanova, E. N., Shenkarev, Z. O., Shulepko, M. A., Mineev, K. S., D'Hoedt, D., Kasheverov, I. E., Filkin, S. Y., Krivolapova, A. P., Janickova, H., Dolezal, V., Dolgikh, D. A., Arseniev, A. S., Bertrand, D., Tsetlin, V. I., and Kirpichnikov, M. P. (2011) NMR structure and action on nicotinic acetylcholine receptors of water-soluble domain of human LYNX1. J. Biol. Chem. 286, 10618–10627) revealed the attachment at the agonist-binding site in the acetylcholine-binding protein (AChBP) and muscle nAChR but outside it, in the neuronal nAChRs. Here, we obtained a series of ws-LYNX1 mutants (T35A, P36A, T37A, R38A, K40A, Y54A, Y57A, K59A) and examined by radioligand analysis or patch clamp technique their interaction with the AChBP, Torpedo californica nAChR and chimeric receptor composed of the α7 nAChR extracellular ligand-binding domain and the transmembrane domain of α1 glycine receptor (α7-GlyR). Against AChBP, there was either no change in activity (T35A, T37A), slight decrease (K40A, K59A), and even enhancement for the rest mutants (most pronounced for P36A and R38A). With both receptors, many mutants lost inhibitory activity, but the increased inhibition was observed for P36A at α7-GlyR. Thus, there are subtype-specific and common ws-LYNX1 residues recognizing distinct targets. Because ws-LYNX1 was inactive against glycine receptor, its “non-classical” binding sites on α7 nAChR should be within the extracellular domain. Micromolar affinities and fast washout rates measured for ws-LYNX1 and its mutants are in contrast to nanomolar affinities and irreversibility of binding for α-bungarotoxin and

  6. DNA binding and topoisomerase II inhibitory activity of water-soluble ruthenium(II) and rhodium(III) complexes.


    Singh, Sanjay Kumar; Joshi, Shweta; Singh, Alok Ranjan; Saxena, Jitendra Kumar; Pandey, Daya Shankar


    Water-soluble piano-stool arene ruthenium complexes based on 1-(4-cyanophenyl)imidazole (CPI) and 4-cyanopyridine (CNPy) with the formulas [(eta6-arene)RuCl2(L)] (L = CPI, eta6-arene = benzene (1), p-cymene (2), hexamethylbenzene (3); L = CNPy, eta6-arene = benzene (4), p-cymene (5), hexamethylbenzene (6)) have been prepared by our earlier methods. The molecular structure of [(eta6-C6Me6)RuCl2(CNPy)] (6) has been determined crystallographically. Analogous rhodium(III) complex [(eta5-C5Me5)RhCl2(CPI)] (7) has also been prepared and characterized. DNA interaction with the arene ruthenium complexes and the rhodium complex has been examined by spectroscopic and gel mobility shift assay; condensation of DNA and B-->Z transition have also been described. Arene ruthenium(II) and EPh3 (E = P, As)-containing arene ruthenium(II) complexes exhibited strong binding behavior, however, rhodium(III) complexes were found to be Topo II inhibitors with an inhibition percentage of 70% (7) and 30% (7a). Furthermore, arene ruthenium complexes containing polypyridyl ligands also act as mild Topo II inhibitors (10%, 3c and 40%, 3d) in contrast to their precursor complexes. Complexes 4-6 also show significant inhibition of beta-hematin/hemozoin formation activity. PMID:18001110

  7. Impact of tree cutting on water-soluble organic compounds in podzolic soils of the European North-East

    NASA Astrophysics Data System (ADS)

    Lapteva, Elena; Bondarenko, Natalia; Shamrikova, Elena; Kubik, Olesya; Punegov, Vasili


    Water-soluble organic compounds (WOCs) and their single components, i.e. low-molecular organic acids, alcohols, and carbohydrates, attain a great deal of attention among soil scientists. WOCs are an important component of soil organic matter (SOM) and form as a results of different biological and chemical processes in soils. These processes are mainly responsible for formation and development of soils in aboveground ecosystems. The purpose of the work was identifying qualitative and quantitative composition of low-molecular organic substances which form in podzolic loamy soils against natural reforestation after spruce forest cutting. The studies were conducted on the territory of the European North-East of Russia, in the middle taiga subzone (Komi Republic, Ust-Kulom region). The study materials were soil of undisturbed bilberry spruce forest (Sample Plot 1 (SP1)) and soils of different-aged tree stands where cutting activities took place in winter 2001/2002 (SP2) and 1969/1970 (SP3). Description of soils and vegetation cover on the plots is given in [1]. Low-molecular organic compounds in soil water extracts were identified by the method of gas chromatography mass-spectrometry [2, 3]. Finally, reforestationafterspruceforestcutting was found to be accompanied by different changes in soil chemical composition. In contrast with soils under undisturbed spruce forest, organic soil horizons under different-aged cuts decreased in organic carbon reserves and production of low-molecular organic compounds, changed in soil acidity. Within the soil series of SP1→SP2→SP3, the highest content of WOCs was identified for undisturbed spruce forest (738 mg kg-1 soil). In soils of coniferous-deciduous forests on SP1 and SP3, WOC content was 294 and 441 mg kg-1 soil, correspondingly. Soils at cuts decreased in concentration of any water-soluble low-molecular SOM components as low-molecular acids, alcohols, and carbohydrates. Structure of low-molecular WOCs in the study podzolic

  8. Preparations and properties of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials.


    Watanabe, Shoji


    This short review describes various types of anti-corrosion additives of water-soluble metal working fluids for aluminum alloy materials. It is concerned with synthetic additives classified according to their functional groups; silicone compounds, carboxylic acids and dibasic acids, esters, Diels-Alder adducts, various polymers, nitrogen compounds, phosphoric esters, phosphonic acids, and others. Testing methods for water-soluble metal working fluids for aluminum alloy materials are described for a practical application in a laboratory. PMID:18075217

  9. Water solubility of selected C9-C18 alkanes using a slow-stir technique: Comparison to structure - property models.


    Letinski, Daniel J; Parkerton, Thomas F; Redman, Aaron D; Connelly, Martin J; Peterson, Brian


    Aqueous solubility is a fundamental physical-chemical substance property that strongly influences the distribution, fate and effects of chemicals upon release into the environment. Experimental water solubility was determined for 18 selected C9-C18 normal, branched and cyclic alkanes. A slow-stir technique was applied to obviate emulsion formation, which historically has resulted in significant overestimation of the aqueous solubility of such hydrophobic liquid compounds. Sensitive GC-MS based methods coupled with contemporary sample extraction techniques were employed to enable reproducible analysis of low parts-per billion aqueous concentrations. Water solubility measurements for most of the compounds investigated, are reported for the first time expanding available data for branched and cyclic alkanes. Measured water solubilities spanned four orders of magnitude ranging from 0.3 μg/L to 250 μg/L. Good agreement was observed for selected alkanes tested in this work and reported in earlier literature demonstrating the robustness of the slow-stir water solubility technique. Comparisons of measured alkane water solubilities were also made with those predicted by commonly used quantitative structure-property relationship models (e.g. SPARC, EPIWIN, ACD/Labs). Correlations are also presented between alkane measured water solubilities and molecular size parameters (e.g. molar volume, solvent accessible molar volume) affirming a mechanistic description of empirical aqueous solubility results and prediction previously reported for a more limited set of alkanes. PMID:26924078

  10. Water-soluble and solid-state speciation of phosphorus in stabilized sewage sludge.


    Huang, Xiao-Lan; Shenker, Moshe


    Three chemicals, ferrous sulfate (Fe-sul), calcium oxide (CaO), and aluminum sulfate (alum), were used to stabilize phosphorus (P) in fresh, anaerobically digested sewage sludge (FSS). The chemically stabilized sludge materials and biosolids compost (BSC) were compared with the FSS with respect to water-soluble phosphorus (WSP) content in its inorganic (WSP(i)) and organic (WSP(o)) forms as well as water-soluble organic carbon (DOC). Solid-state P speciation was further probed by X-ray diffraction (XRD) and scanning electron microscopy (SEM) equipped with energy-dispersive X-ray elemental spectrometry (EDXS). Water-soluble P was effectively controlled by a wide range of Fe-sul or CaO additions to the sludge (Ca to P ratio = 3.47-17.72, Fe to P ratio = 1.01-16.53), but by only a narrow range (Al to P ratio = 1.04-2.87) of alum addition. The WSP content in the BSC was also depressed, but to a lesser extent. The pH in the treated sludge ranged from 3.0 to 12.5 and served as a key factor to control P chemistry. No correlation was observed between DOC and WSP(o). No crystallized Ca-P minerals were detected in the CaO-stabilized sludge, but brushite crystallization seemed to be obtained by low addition of Fe-sul and alum. Variscite and strengite crystallization was obtained following high addition of Fe-sul or alum, as detected by XRD and SEM-EDXS. Adsorption of P by newly formed Fe-hydroxide seems to play an important role in the Fe-sul-stabilized sludge. We concluded that administration of the tested chemicals at the proper rate can effectively reduce the hazard of P release and leaching from sludge. PMID:15356251

  11. Water-soluble germanium(0) nanocrystals: cell recognition and near-infrared photothermal conversion properties.


    Lambert, Timothy N; Andrews, Nicholas L; Gerung, Henry; Boyle, Timothy J; Oliver, Janet M; Wilson, Bridget S; Han, Sang M


    Surfactant-passivated germanium nanocrystals (Ge(0) NCs) 3-5 nm in diameter were synthesized and encapsulated with functionalized phospholipids to yield water-soluble Ge(0) NCs. Upon encapsulation, the NCs retained their cubic crystalline phase and displayed good resistance to oxidation, as determined by transmission electron microscopy and X-ray photoelectron spectroscopy. As a test of their cell compatibility, the ability of carboxyfluorescein (CF)-labeled dinitrophenyl (DNP)-functionalized Ge(0) NCs to crosslink dinitrophenol-specific immunoglobulin E antibodies on the surface of mast cells (RBL-2H3) was examined in vitro. Treatment with a multivalent DNP antigen (i.e., DNP-Ge(0) NCs or CF-DNP-Ge(0) NCs) caused crosslinking of FcepsilonRI receptors and cellular responses, which were evaluated with morphological and colorimetric assays and live-cell fluorescence microscopy. Incubation of RBL-2H3 cells with Ge(0) NCs for approximately 24 h gave less than a 2 % increase in cell death as compared to DNP-functionalized bovine serum albumin. When irradiated with near-infrared (NIR) radiation (lambda(exc)=770 nm, 1.1 W cm(-2)) from a continuous-wave Ti:sapphire laser, the bulk-solution temperature of a toluene solution containing 20 mg mL(-1) Ge(0) NCs increased by approximately 35 degrees C within 5 min. Phospholipid-encapsulated water-soluble Ge(0) NCs at concentrations of 1.0 mg mL(-1) also displayed stable photothermal behavior under repetitive and prolonged NIR laser exposures in water, to yield a temperature increase of approximately 20 degrees C within 5 min (lambda(exc)=770 nm, 0.9 W cm(-2)). The photothermal efficiency of water-soluble Ge(0) NCs compares favorably with a recent report for Au nanoshells. PMID:17299826

  12. Characterization of water-soluble organic matter isolated from atmospheric fine aerosol

    NASA Astrophysics Data System (ADS)

    Kiss, Gyula; Varga, BáLint; Galambos, IstváN.; Ganszky, Ildikó


    Atmospheric fine aerosol (dp < 1.5 μm) was collected at a rural site in Hungary from January to September 2000. The total carbon concentration ranged from 5 to 13 μg m-3 and from 3 to 6 μg m-3 in the first three months and the rest of the sampling period, respectively. On average, water-soluble organic carbon (WSOC) accounted for 66% of the total carbon concentration independent of the season. A variable fraction of the water-soluble organic constituents (38-72% of WSOC depending on the sample) was separated from inorganic ions and isolated in pure organic form by using solid phase extraction on a copolymer sorbent. This fraction was experimentally characterized by an organic matter to organic carbon mass ratio of 1.9, and this value did not change with the seasons. Furthermore, the average elemental composition (molar ratio) of C:H:N:O ≈ 24:34:1:14 of the isolated fraction indicated the predominance of oxygenated functional groups, and the low hydrogen to carbon ratio implied the presence of unsaturated or polyconjugated structures. These conclusions were confirmed by UV, fluorescence, and Fourier transform infrared (FTIR) studies. On the basis of theoretical considerations, the organic matter to organic carbon mass ratio was estimated to be 2.3 for the nonisolated water-soluble organic fraction, resulting in an overall ratio of 2.1 for the WSOC. In order to extend the scope of this estimation to the total organic carbon, which is usually required in mass closure calculations, the aqueous extraction was followed by sequential extraction with acetone and 0.01 M NaOH solution. As a result, a total organic matter to total organic carbon mass ratio of 1.9-2.0 was estimated, but largely on the basis of experimental data.

  13. Design of multicomponent photocatalysts for hydrogen production under visible light using water-soluble titanate nanodisks.


    Dinh, Cao-Thang; Pham, Minh-Hao; Seo, Yongbeom; Kleitz, Freddy; Do, Trong-On


    We report the design of efficient multicomponent photocatalysts (MPs) for H2 production under visible light by using water-soluble ultrathin titanate nanodisks (TNDs) stabilized by tetraethylammonium cations (TEA(+)) as building blocks. The photocatalysts are designed in such a way to significantly enhance simultaneously the efficiency of the three main steps in the photocatalytic process i.e., light absorption, charge separation and catalytic reaction. We show, as an example, the construction of water-soluble CdS-TND-Ni MPs. The designed CdS-TND-Ni MPs, in which CdS nanoparticles and TNDs are intimately assembled to enhance the charge transfer and surface area, are controlled in composition to optimize visible light absorption. The conception of the MPs allows them to be highly dispersed in water which markedly improves the photocatalytic H2 production process. Most importantly, a Ni co-catalyst is selectively located on the surface of TNDs, enabling vectorial electron transfer from CdS to TND and to Ni, which drastically improves the charge separation. Consequently, under visible light illumination (λ ≥ 420 nm), the optimally designed CdS-TND-Ni MPs could generate H2 from ethanol-water solution with rate as high as 15.326 mmol g(-1) h(-1) during a reaction course of 15 h and with an apparent quantum yield of 24% at 420 nm. Moreover, we also demonstrate that TNDs can be combined with other single or mixed metal sulfide to form water-soluble metal sulfide-TNDs composites which could also be of great interest for photocatalytic H2 production. PMID:24664235

  14. Water-soluble material on aerosols collected within volcanic eruption clouds ( Fuego, Pacaya, Santiaguito, Guatamala).

    USGS Publications Warehouse

    Smith, D.B.; Zielinski, R.A.; Rose, W.I., Jr.; Huebert, B.J.


    In Feb. and March of 1978, filter samplers mounted on an aircraft were used to collect the aerosol fraction of the eruption clouds from three active Guatemalan volcanoes (Fuego, Pacaya, and Santiaguito). The elements dissolved in the aqueous extracts represent components of water-soluble material either formed directly in the eruption cloud or derived from interaction of ash particles and aerosol components of the plume. Calculations of enrichment factors, based upon concentration ratios, showed the elements most enriched in the extracts relative to bulk ash composition were Cd, Cu, V, F, Cl, Zn, and Pb.-from Authors

  15. Effect of water-soluble oxalates in Amaranthus spp. leaves on the absorption of milk calcium.


    Pingle, U; Ramasastri, B V


    1. Amaranthus spp. leaves contain high amounts of oxalates which affect the calcium absorption. This study was done to determine whether removal of the water-soluble oxalates from the leaves by cooking would reduce this deleterious effect. 2. Experimental work done with two types of basal diets on six adult male subjects has shown that the milk Ca absorption was low when leaves cooked without draining away the water were included in the diet. However when the soluble oxalates were removed by throwing away the water after cooking the leaves, the absorption of milk Ca was unaffected. PMID:568935

  16. Green synthesis of water-soluble nontoxic polymeric nanocomposites containing silver nanoparticles

    PubMed Central

    Prozorova, Galina F; Pozdnyakov, Alexsandr S; Kuznetsova, Nadezhda P; Korzhova, Svetlana A; Emel’yanov, Artem I; Ermakova, Tamara G; Fadeeva, Tat’yana V; Sosedova, Larisa M


    New water-soluble nontoxic nanocomposites of nanosized silver particles in a polymer matrix were synthesized by a green chemistry method. Nontoxic poly(1-vinyl-1,2,4-triazole) was used as a stabilizing precursor agent in aqueous medium. Glucose and dimethyl sulfoxide were used as the silver ion-reducing agents to yield silver nanoparticles 2–26 nm and 2–8 nm in size, respectively. The nanocomposites were characterized by transmission electron microscopy, ultraviolet-visible and Fourier transform infrared spectroscopy, X-ray diffraction, atomic absorption, and thermogravimetric data analysis. The nanocomposites showed strong antimicrobial activity against Gram-negative and Gram-positive bacteria. PMID:24790430

  17. Characteristics of new particle formation events in Nanjing, China: Effect of water-soluble ions

    NASA Astrophysics Data System (ADS)

    An, Junlin; Wang, Honglei; Shen, Lijuan; Zhu, Bin; Zou, Jianan; Gao, Jinhui; Kang, Hanqing


    New particle formation (NPF) events and water-soluble ions were studied at the meteorological building on the campus of the Nanjing University of Information Science and Technology (NUIST), which is located in the western part of the Yangtze River Delta (YRD). A wide-range particle spectrometer (WPS) provided particle number size distributions between 10 nm and 10 μm, whereas water-soluble ions for particles with diameters between 10 nm and 18 μm were measured using a 13-stage Nano-MOUDI aerosol sampler and 850 professional Ion Chromatography (IC). Additionally, meteorological data, trace gas concentrations and mass concentration were recorded. Ten NPF days were captured during the measurement period from 08 July to 02 August 2012. The mean aerosol number concentration, which was primarily composed of Aitken-mode particles, i.e., with diameters of 20-100 nm, was 13,664 cm-3, which was 1.9 times larger than that on non-NPF days. The results suggest that the NPF events were only slightly affected by O3, SO2, and NO2; the primary factors affecting NPF events were meteorological factors and air mass directions. NPF events were found to be favorable during the summer in the presence of high temperatures, strong radiation, low humidity, strong winds and clean air masses originating from the southeastern coast. The mean growth rate (GR), formation rate (J10), condensational sink (CS), condensing vapor rate (Q), and condensation vapor (C) were determined to be 7.6 nm h-1, 3.7 cm-3 s-1, 2.8 × 10-2 s-1, 2.9 × 106 cm-3 s-1, and 10.5 × 107 cm-3, respectively, on NPF days. The largest effects of the studied NPF events were on the mass and water-soluble ion concentrations of Aitken-mode particles, followed by nuclei-mode particles; few contributions to accumulation- and coarse-mode particles were observed. Different water-soluble ions were observed to have distinct interactions with the NPF events. The proportions of NH4+, SO42-, NO3-, K+ and Mg2+ in nuclei- and Aitken

  18. Water-soluble chelating polymers for removal of actinides from watewater

    SciTech Connect

    Jarvinen, G.


    Polymer filtration is a technology being developed to recover valuable or regulated metal ions selectively from process or wastewaters. Water-soluble chelating polymers are specially designed to bind selectively with metal ions in aqueous solutions. The polymers molecular weight is large enough so they can be separated and concentrated using available ultrafiltration technology. Water and smaller unbound components of the solution pass freely through the ultrafiltration membrane. The polymers can then be reused by changing the solution conditions to release the metal ions, which are recovered in concentrated form, for recycle or disposal.

  19. Sulfur speciation and stable isotope trends of water-soluble sulfates in mine tailings profiles.


    Dold, Bernhard; Spangenberg, Jorge E


    Sulfur speciation and the sources of water-soluble sulfate in three oxidizing sulfidic mine tailings impoundments were investigated by selective dissolution and stable isotopes. The studied tailings impoundments--Piuquenes, Cauquenes, and Salvador No. 1--formed from the exploitation of the Rio Blanco/La Andina, El Teniente, and El Salvador Chilean porphyry copper deposits, which are located in Alpine, Mediterranean, and hyperarid climates, respectively. The water-soluble sulfate may originate from dissolution of primary ore sulfates (e.g., gypsum, anhydrite, jarosite) or from oxidation of sulfide minerals exposed to aerobic conditions during mining activity. With increasing aridity and decreasing pyrite content of the tailings, the sulfur speciation in the unsaturated oxidation zones showed a trend from dominantly Fe(III) oxyhydroxide fixed sulfate (e.g., jarosite and schwertmannite) in Piuquenes toward increasing presence of water-soluble sulfate at Cauquenes and Salvador No. 1. In the saturated primary zones, sulfate is predominantly present in water-soluble form (mainly as anhydrite and/or gypsum). In the unsaturated zone at Piuquenes and Cauquenes, the delta34S(SO4)values ranged from +0.5 per thousand to +2.0 per thousand and from -0.4 per thousand to +1.4 per thousand Vienna Canyon Diablo Troilite (V-CDT), respectively, indicating a major sulfate source from pyrite oxidation (delta34S(pyrite) = -1.1 per thousand and -0.9 per thousand). In the saturated zone at Piuquenes and Cauquenes, the values ranged from -0.8 per thousand to +0.3 per thousand and from +2.2 per thousand to +3.9 per thousand, respectively. At Cauquenes the 34S enrichment in the saturated zone toward depth indicates the increasing contribution of isotopically heavy dissolved sulfate from primary anhydrite (approximately +10.9 per thousand). At El Salvador No. 1, the delta34S(SO4) average value is -0.9 per thousand, suggesting dissolution of supergene sulfate minerals (jarosite, alunite, gypsum

  20. Application of water-soluble polymer in dewatering of fine coal

    SciTech Connect

    Xingyong, W.


    The addition of water-soluble polymer to fine coal slurry to enhance dewatering process of fine coal is considered to be one of the most effective ways of solving the problems of dewatering of fine coal. A series of tests are conducted with a vacuum dewatering apparatus to study the effects of various factors such as the species of polymer, polymer dosage and its ways of addition, and the pH of fine coal slurry on filtrating and dewatering of fine coal.

  1. Synthesis of a novel water-soluble zinc phthalocyanine and its CT DNA-damaging studies

    NASA Astrophysics Data System (ADS)

    Wang, Tianhui; Wang, Ao; Zhou, Lin; Lu, Shan; Jiang, Weiwei; Lin, Yun; Zhou, Jiahong; Wei, Shaohua


    A novel 3-(4-methoxybenzylamino) propanoic acid substituted water-soluble zinc phthalocyanine (CNPcZn) was synthesized. The interaction between CNPcZn with calf thymus DNA (CT DNA) was studied using spectroscopic methods. The studies indicated that CNPcZn has strong affinity to CT DNA, and furthermore, CNZnPc showed excellent photodamaging activity to CT DNA. Above results indicated that such CNPcZn has great potential to be used as an effective photosensitizer in the field of photodynamic therapy.

  2. Efficient Route to Highly Water-Soluble Aromatic Cyclic Hydroxamic Acid Ligands

    SciTech Connect

    Seitz, Michael; Raymond, Kenneth N.


    2-Hydroxyisoquinolin-1-one (1,2-HOIQO) is a new member of the important class of aromatic cyclic hydroxamic acid ligands which are widely used in metal sequestering applications and metal chelating therapy. The first general approach for the introduction of substituents at the aromatic ring of the chelating moiety is presented. As a useful derivative, the highly water-soluble sulfonic acid has been synthesized by an efficient route that allows general access to 1,2-HOQIO 3-carboxlic acid amides, which are the most relevant for applications.

  3. A property-matched water-soluble analogue of the benchmark ligand PPh3.


    Ferreira, Michel; Bricout, Hervé; Hapiot, Frédéric; Sayede, Adlane; Tilloy, Sébastien; Monflier, Eric


    A series of sulfonated biphenylphosphanes were readily prepared from commercially available, inexpensive, and air-stable organic compounds. Of these, the trisulfonated trisbiphenylphosphane can be considered as a true water-soluble analogue of PPh(3) as the cone angle and basicity of both phosphanes are very close and result in a similar coordination mode on palladium and rhodium complexes. The catalytic performance of the trisulfonated trisbiphenylphosphane was evaluated in the aqueous hydroformylation of 1-decene and the Tsuji-Trost reaction. PMID:18702165

  4. Induction of classical activation of macrophage in vitro by water soluble chitin

    NASA Astrophysics Data System (ADS)

    Jeon, Dong-Won; Ahn, Woong Shick; You, Su Jung; Chae, Gue Tae; Shim, Young Bock; Chun, Heung Jae


    The purpose of this study is to understand the effect of chitin on macrophage mediated immunity, which is a significant factor to wound healing and tissue regeneration. In this work, water soluble chitin (WSC) was prepared by re-acetylation of chitosan and was treated with the murine RAW 264.7 macrophage cell lines (ATCC TIB-71). WSC induced classical activation in the RAW 264.7 cells, accompanied by the induction of associated genes. The results suggest that WSC is one of the functional chitin molecules that are responsible for the immune response, especially present in macrophage classical activation.

  5. Embryotoxicity and biotransformation responses in zebrafish exposed to water-soluble fraction of crude oil.


    Pauka, Luciana M; Maceno, Marcell; Rossi, Stefani C; Silva de Assis, Helena C


    The toxic effects of water-soluble fraction (WSF) of crude oil (API27, Petrobras Campos Basin, Brazil) were evaluated during the early life stages of zebrafish, as well as its biotransformation in juvenile fish. Embryonic development was studied during 96 h. Reduced heartbeat rate, weak pigmentation, tail defects, and embryo mortality were observed for all of the tested concentrations of the WSF. Activities of the biotransformation enzymes were induced at the highest concentrations, showing that these enzymes played a role in its elimination. As shown in this study the crude oil WSF altered the normal embryonic development of fish. PMID:21404046

  6. Nanometer-Scale Water-Soluble Macrocycles from Nanometer-Sized Amino Acids

    PubMed Central

    Gothard, Chris M.


    This paper introduces the unnatural amino acids m-Abc2K and o-Abc2K as nanometersized building blocks for the creation of water-soluble macrocycles with well-defined shapes. m-Abc2K and o-Abc2K are homologues of the nanometer-sized amino acid Abc2K, which we recently introduced for the synthesis of water-soluble molecular rods of precise length. [J. Am. Chem. Soc. 2007, 129, 7272]. Abc2K is linear (180°), m-Abc2K creates a 120° angle, and o-Abc2K creates a 60° angle. m-Abc2K and o-Abc2K are derivatives of 3’-amino-[1,1’-biphenyl]-4-carboxylic acid and 2’-amino-[1,1’-biphenyl]-4-carboxylic acid, with two propyloxyammonium side chains for water solubility. m-Abc2K and o-Abc2K are prepared as Fmoc-protected derivatives Fmoc-m-Abc2K(Boc)-OH (1a) and Fmoc-o-Abc2K(Boc)-OH (1b). These derivatives can be used alone or in conjunction with Fmoc-Abc2K(Boc)-OH (1c) as ordinary amino acids in Fmoc-based solid-phase peptide synthesis. Building blocks 1a–c were used to synthesize macrocyclic “triangles” 9a–c, “parallelograms” 10a,b, and hexagonal “rings” 11a–d. The macrocycles range from a trimer to a dodecamer, with ring sizes from 24 to 114 atoms, and are 1–4 nm in size. Molecular modeling studies suggest that all the macrocycles except 10b should have well-defined triangle, parallelogram, and ring shapes if all of the amide linkages are trans and the ortho-alkoxy substituents are intramolecularly hydrogen bonded to the amide NH groups. The macrocycles have good water solubility and are readily characterized by standard analytical techniques, such as RP-HPLC, ESI-MS, and NMR spectroscopy. 1H and 13C NMR studies suggest that the macrocycles adopt conformations with all trans-amide linkages in CD3OD, that the “triangles” and “parallelograms” maintain these conformations in D2O, and that the “rings” collapse to form conformations with cis-amide linkages in D2O. PMID:20020731

  7. Formation of water soluble complexes of ?: solid-state reaction between tertiary amines and ?

    NASA Astrophysics Data System (ADS)

    Mohan, H.; Priyadarsini, K. I.; Tyagi, A. K.; Mittal, J. P.


    Water soluble complexes of 0953-4075/29/21/015/img3 have been prepared on solid-state mechano-chemical reaction between 0953-4075/29/21/015/img3 and tertiary amines (hexamine, DABCO) at room temperature 0953-4075/29/21/015/img5. The product is characterized by x-ray diffraction and FTIR methods. It is presumably due to the charge transfer interactions between electron affinic 0953-4075/29/21/015/img3 and electron rich tertiary amines.

  8. Water-Soluble Quantum Dots for Multiphoton Fluorescence Imaging in Vivo

    NASA Astrophysics Data System (ADS)

    Larson, Daniel R.; Zipfel, Warren R.; Williams, Rebecca M.; Clark, Stephen W.; Bruchez, Marcel P.; Wise, Frank W.; Webb, Watt W.


    The use of semiconductor nanocrystals (quantum dots) as fluorescent labels for multiphoton microscopy enables multicolor imaging in demanding biological environments such as living tissue. We characterized water-soluble cadmium selenide-zinc sulfide quantum dots for multiphoton imaging in live animals. These fluorescent probes have two-photon action cross sections as high as 47,000 Goeppert-Mayer units, by far the largest of any label used in multiphoton microscopy. We visualized quantum dots dynamically through the skin of living mice, in capillaries hundreds of micrometers deep. We found no evidence of blinking (fluorescence intermittency) in solution on nanosecond to millisecond time scales.

  9. Water-soluble quantum dots for multiphoton fluorescence imaging in vivo.


    Larson, Daniel R; Zipfel, Warren R; Williams, Rebecca M; Clark, Stephen W; Bruchez, Marcel P; Wise, Frank W; Webb, Watt W


    The use of semiconductor nanocrystals (quantum dots) as fluorescent labels for multiphoton microscopy enables multicolor imaging in demanding biological environments such as living tissue. We characterized water-soluble cadmium selenide-zinc sulfide quantum dots for multiphoton imaging in live animals. These fluorescent probes have two-photon action cross sections as high as 47,000 Goeppert-Mayer units, by far the largest of any label used in multiphoton microscopy. We visualized quantum dots dynamically through the skin of living mice, in capillaries hundreds of micrometers deep. We found no evidence of blinking (fluorescence intermittency) in solution on nanosecond to millisecond time scales. PMID:12775841

  10. Evaluation of hydration in a water-soluble polymer by terahertz spectroscopy

    NASA Astrophysics Data System (ADS)

    Kawabe, Shunsuke; Seki, Munetoshi; Tabata, Hitoshi


    In this study, we have evaluated the hydration properties of water-soluble polymers by terahertz spectroscopy. In particular, we focused on polyvinylpyrrolidone which has potential use for a wide range of applications as a biomaterial. The dielectric loss of samples obtained by the terahertz spectroscopy was found to strongly depend on the molecular weight of the polymers and the density of the solution. We revealed that the hydration number per monomer depends on the molecular weight of the polymer. It is also deduced that the hydration number is affected by the conformation of the polymer in the solution.