Abstract：
:In drug release systems using hydrogels as carriers, the presence of the polymer network will reduce the drug release rate, which can extend the release period. For a controlled-release process of drug, usually the ideal situation is to get a zero-order drug release rate. In this paper, the mathematical model of hydrogel swelling processes is constructed on the basis of a biphasic theory, and then an integrated equation that considers both water convection and drug diffusion phenomena is used to describe the drug release process. The effects of the initial drug concentration with nonuniform distributions along the radial direction of hydrogel carriers on the release of drugs are studied through simulating two-dimensional hydrogel swelling processes by means of the COMSOL Multiphysics software. The simulation results show that along with the hydrogel swelling, the drug release rate is changing, and the major influencing factors of the drug release rate are water convection and drug diffusion coefficient, which are affected by water volume fraction, drug concentration distribution in matrix, and carrier radius. The results also indicate that the initial drug concentration distribution following a sine curve can result in an ideal zero-order release process.
journal_name
J Pharm Scijournal_title
Journal of pharmaceutical sciencesauthors
Xu Y,Jia Y,Wang Z,Wang Zdoi
10.1002/jps.23497subject
Has Abstractpub_date
2013-05-01 00:00:00pages
1532-43issue
5eissn
0022-3549issn
1520-6017pii
S0022-3549(15)31115-1journal_volume
102pub_type
杂志文章abstract：:An automated potentiometric procedure was used for studying in vitro dissolution kinetics of acidic drugs. Theoretical considerations indicated that the pH-stat method could be used to establish approximate sink conditions or, possibly, a perfect sink. Data obtained from dissolution studies using the pH-stat method we...
journal_title：Journal of pharmaceutical sciences
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doi：10.1002/jps.2600670837
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abstract：:In this study, injectable microspheres were developed for the local treatment of joint degeneration in rheumatoid arthritis (RA). Microspheres loaded with triamcinolone (TA), a corticosteroid drug, and/or raloxifene (Ral), a cartilage regenerative drug, were prepared with a biodegradable and biocompatible polymer, pol...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
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journal_title：Journal of pharmaceutical sciences
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doi：10.1002/jps.2600670212
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journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600820310
更新日期：1993-03-01 00:00:00
abstract：:The disposition of radioactivity following oral administration of 14C-norgestimate was compared to that following administration of the drug in combination with 3H-ethinyl estradiol in humans. Seven normal, healthy female subjects were each administered one capsule orally containing 14C-norgestimate either alone (74.4...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600671020
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journal_title：Journal of pharmaceutical sciences
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doi：10.1002/jps.2600720930
更新日期：1983-09-01 00:00:00
abstract：:Successful development of stable solid protein formulations usually requires the addition of one or several excipients to achieve optimal stability. In these products, there is a potential risk of an inhomogeneous distribution of the various ingredients, specifically the ratio of protein and stabilizer may vary. Such ...
journal_title：Journal of pharmaceutical sciences
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abstract：:A potentiometric study of lithium complexation with tyramine, dopamine, norepinephrine, and 5-hydroxytryptamine was undertaken using monovalent cationic selective and pH glass electrodes. The conditional stability constants for the lithium catecholamine complexes were calculated for a range of pH values from direct po...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600750117
更新日期：1986-01-01 00:00:00
abstract：:Tryptophan (Trp) oxidation in proteins leads to a number of events, including changes in color, higher order structure (HOS), and biological activity. We describe here a number of new findings through a comprehensive characterization of 6 monoclonal antibodies (mAbs) following selective oxidation of Trp residues by 2,...
journal_title：Journal of pharmaceutical sciences
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abstract：:In vitro studies on the photodecomposition of uric acid in the presence of the monosodium salt of riboflavin 5'-phosphate in buffers at various pH values, in methanol, and in human plasma are reported. The decomposition rate increased with increasing pH and was independent of solvent or buffer species. The mechanism a...
journal_title：Journal of pharmaceutical sciences
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doi：10.1002/jps.2600661115
更新日期：1977-11-01 00:00:00
abstract：:The synthesis, hydrolysis rate, and bioavailability of 1-(p-acetaminophenoxy)-1-ethoxyethane, an acetaminophen prodrug, are described. The prodrug is less soluble than acetaminophen and stable at neutral pH. However, in an acidic environment, the compound cleaves rapidly, generating acetaminophen. When both the prodru...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600670426
更新日期：1978-04-01 00:00:00
abstract：:This work investigates the use of spray freeze-drying (SFD) to produce protein loaded particles suitable for epidermal delivery. In the first part of the study, the effects of formulation and process conditions on particle properties are examined. Aqueous solutions of trehalose produce SFD particles in the size range ...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.10204
更新日期：2002-10-01 00:00:00
abstract：:In 2005, the World Health Organization (WHO) proposed that provided an active pharmaceutical ingredient could meet certain criteria, bioequivalence could be evaluated with a set of laboratory tests, obviating the need for expensive and time-consuming pharmacokinetic studies in humans. The aim of this work was to deter...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.22349
更新日期：2011-03-01 00:00:00
abstract：:Two polymorphs of the 1:1 fumarate salt of 1,4-diazabicyclo[3.2.2]nonane-4-carboxylic acid 4-bromophenyl ester, developed for the treatment of cognitive symptoms of schizophrenia and Alzheimer disease, have been characterized. The 2 crystal structures have been solved, and their phase relationships have been establish...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1016/j.xphs.2015.10.015
更新日期：2016-01-01 00:00:00
abstract：:The inclusion complexation of homologous derivatives of steroid hormones with cyclodextrins and 2-hydroxypropyl-beta-cyclodextrin (2-HP-beta-CD) was investigated with regard to underlying structure-interaction relationship. The interaction was studied by phase solubility analysis and stabilization effects of complex f...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600810808
更新日期：1992-08-01 00:00:00
abstract：:The pre-equilibrium capillary zone electrophoretic (pre-eq CZE) method to determine association constants of active anionic forms of antithyroid drugs: 6-n-propyl-2-thiouracil (PTU), 6-methyl-2-thiouracil (MTU), 2-thiouracil (TU) with bovine serum albumin (BSA) under physiological pH 7.4 has been developed for the fir...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.21915
更新日期：2010-03-01 00:00:00
abstract：:The stability of therapeutic proteins formulated in prefilled syringes (PFS) may be negatively impacted by the exposure of protein molecules to silicone oil-water interfaces and air-water interfaces. In addition, agitation, such as that experienced during transportation, may increase the detrimental effects (i.e., pro...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.23973
更新日期：2014-06-01 00:00:00
abstract：:Electrolytes often break emulsions to which they were added as active ingredients, adjuvants, or impurities. The stability of oil-in-water emulsions containing octoxynol 9 NF as the emulsifier and various added electrolytes was investigated by measuring droplet size, turbidity, and oil separation on storage at various...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600721216
更新日期：1983-12-01 00:00:00
abstract：:There is a recognized need for new approaches to understand unit operations with pharmaceutical relevance. A method for analyzing complex interactions in experimental data is introduced. Higher-order interactions do exist between process parameters, which complicate the interpretation of experimental results. In this ...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.21565
更新日期：2009-05-01 00:00:00
abstract：:Sustained-release formulations such as hydroxypropyl methylcellulose (HPMC)-based hydrophilic matrix tablets of poorly water-soluble drugs often result in incomplete release because of the poor solubility and dissolution rate of the drug in the hydrophilic matrix. Sulfobutylether-beta-cyclodextrins ((SBE)(7M)-beta-CDs...
journal_title：Journal of pharmaceutical sciences
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doi：10.1002/jps.1034
更新日期：2001-07-01 00:00:00
abstract：:The objective of this study is to understand the underlying mechanisms responsible for the superior stability of indomethacin (INM)-Eudragit® E PO (E PO) system by exploring the miscibility and intermolecular interactions through the combination of thermal, rheological, and spectroscopic analysis. The zero shear-rate ...
journal_title：Journal of pharmaceutical sciences
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doi：10.1002/jps.23075
更新日期：2012-06-01 00:00:00
abstract：:The geometry and structural features of the inclusion complexes of beta-cyclodextrin (beta-CD) with the chiral antiamnesic drugs (+/-)-1-benzyl-4-hydroxymethylpyrrolidin-2-one (WEB-1868). (+/-)-1-benzenesulfonyl-5-ethoxypyrrolidin-2-one (RU-35929), and (+/-)-1-(3-pyridinlysulfonyl)-5-ethoxypyrrolidin-2-one (RU-47010) ...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600811205
更新日期：1992-12-01 00:00:00
abstract：:Biopharmaceuticals represent an important and growing class of medicines. Immunogenic responses to biopharmaceuticals in patients can sometimes result in reduced safety and efficacy. Although multiple factors are known to influence immunogenicity, our understanding of the complex underlying mechanisms remains imperfec...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.23247
更新日期：2012-10-01 00:00:00
abstract：:A method is described for the analysis of amitriptyline, doxepin, imipramine, nortriptyline, desmethyldoxepin, desipramine, and protriptyline in human plasma utlizing GLC-chemical-ionization mass spectrometry with selected ion monitoring. The assay is highly specific and is quantitative to at least 1 ng/ml with a stan...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600670106
更新日期：1978-01-01 00:00:00
abstract：:Nanocrystals have emerged as a potential formulation strategy to eliminate the bioavailability-related problems by enhancing the initial dissolution rate and moderately super-saturating the thermodynamic solubility. This review contains an in-depth knowledge of, the processing method for formulation, an accurate quant...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章,评审
doi：10.1002/jps.24694
更新日期：2016-01-01 00:00:00
abstract：:The absorption of the model drug carbenoxolone was reevaluated using an in situ rat intestinal perfusion technique in which disappearance from the intestinal lumen, binding to the perfused jejunal segment, and appearance in the mesenteric (jejunal) vein were measured. The effect of the degree of ionization on these pr...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600790510
更新日期：1990-05-01 00:00:00
abstract：:Ascorbic acid (100 mg/ml) and sodium bisulfite (0.5 and 20 mg/ml) prevented more than 10% oxidation of apomorphine hydrochloride in water maintained at room temperature over 1-3 days. Refrigeration at 5 degrees prevented oxidation of apomorphine hydrochloride in aqueous solutions for 1 week. Neither ascorbic acid nor ...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600690830
更新日期：1980-08-01 00:00:00
abstract：:Deiodination of diatrizoic acid, an anionic radiopaque, was found to be catalyzed by Cu(II). Through a detailed study of o-iodobenzoic acid, a model compound, the copper-catalyzed SN1 mechanism was established based on observations of common ion, salt, and pH effects. Meta- and para-iodobenzoic acids were unreactive. ...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600690616
更新日期：1980-06-01 00:00:00
abstract：:To design safe, efficient synthetic gene therapy vectors, it is desirable to understand the intracellular mechanisms that facilitate their delivery from the cell surface to the nucleus. Elements of the cytoskeleton and molecular motor proteins are known to play a pivotal role in most intracellular active transport pro...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.21106
更新日期：2008-04-01 00:00:00
abstract：:One of the most important challenges for pharmaceutical and cosmetic industries is solubilization and preservation of their active ingredients. Therefore, most of these formulations contain irritant chemical additives to improve their shelf-life and the solubility of hydrophobic ingredients. An interesting alternative...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1016/j.xphs.2019.02.010
更新日期：2019-07-01 00:00:00
