Calculation of the dimensions of drug-polymer devices based on diffusion parameters.


:The release kinetics of a polymeric-controlled release device are determined by its geometry and dimensions. A method to calculate the required size and shape of diffusion-controlled dosage forms to achieve a particular release profile is presented. The diffusion parameters are determined for various drugs (theophylline, diltiazem hydrochloride and caffeine) with thin ethyl cellulose (EC) films, containing different plasticizers [dibutyl sebacate (DBS) and acetyl tributyl citrate (ATBC)]. Computer simulations are then used to predict the drug release kinetics from various dosage forms (e.g. microparticles and cylinders). The practical benefit of these simulations is to optimize the geometry and dimensions of a controlled release device without the need of experimental studies. To verify the theoretical predictions, the release kinetics of theophylline from EC/ATBC microparticles of different size have also been determined experimentally. Good agreement is found between theory and experiment, proving the validity of the presented method.


J Pharm Sci


Siepmann J,Ainaoui A,Vergnaud JM,Bodmeier R




Has Abstract


1998-07-01 00:00:00














  • Alternative Manufacturing Concepts for Solid Oral Dosage Forms From Drug Nanosuspensions Using Fluid Dispensing and Forced Drying Technology.

    abstract::Flexible manufacturing technologies for solid oral dosage forms with a continuous adjustability of the manufactured dose strength are of interest for applications in personalized medicine. This study explored the feasibility of using microvalve technology for the manufacturing of different solid oral dosage form conce...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Bonhoeffer B,Kwade A,Juhnke M

    更新日期:2018-03-01 00:00:00

  • Nonlinear enthalpy-entropy compensation for the solubility of phenacetin in dioxane-water solvent mixtures.

    abstract::The solubility of phenacetin was determined at five temperatures in solvent mixtures of aprotic-amphiprotic mixtures of dioxane and water. Enthalpy-entropy compensation analysis is used to study the effect of changing polarity of the medium on the solute. The apparent heats of solution and free energies of solution ar...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Bustamante C,Bustamante P

    更新日期:1996-10-01 00:00:00

  • Quantitative determination of hexamidine isethionate in pharmaceutical preparations by high-performance liquid chromatography.

    abstract::Hexamidine isethionate in various pharmaceutical formulations was analyzed quantitatively by high-performance liquid chromatography. The method is rapid, accurate, and precise. Excellent results were obtained from four commercial bases. ...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Taylor P,Braddock PD,Ross S

    更新日期:1983-12-01 00:00:00

  • In vivo evaluation of controlled-release products.

    abstract::A theoretical investigation has been conducted to understand the deconvolution method used for evaluating the in vivo release rate of an oral controlled-release product from the plasma drug concentration versus time profile. The theory is based on well-accepted pharmacokinetic compartmental models. The cumulative amou...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Hwang SS,Bayne W,Theeuwes F

    更新日期:1993-11-01 00:00:00

  • Presystemic elimination of drugs: theoretical considerations for quantifying the relative contribution of gut and liver.

    abstract::From a consideration of the basic processes involved in drug elimination, the fraction of drug cleared by the gut and by the liver were described as functions of availability and hepatic clearance. For a drug given orally, a plot of the fraction of drug cleared by the gut or liver against alpha, a proportionality cons...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Minchin RF,Ilett KF

    更新日期:1982-04-01 00:00:00

  • Impact of Precipitation of Antibody Therapeutics After Subcutaneous Injection on Pharmacokinetics and Immunogenicity.

    abstract::Antibody therapeutics with poor solubility in the subcutaneous matrix may carry unintended risks when administered to patients. The objective of this work was to estimate the risk of antibodies that precipitate in vitro at neutral pH by determining the impact of poor solubility on distribution of the drug from the inj...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Kinderman F,Yerby B,Jawa V,Joubert MK,Joh NH,Malella J,Herskovitz J,Xie J,Ferbas J,McBride HJ

    更新日期:2019-06-01 00:00:00

  • Zinc(II) in saliva: determination of concentrations produced by different formulations of zinc gluconate lozenges containing common excipients.

    abstract::A study of the pH of saliva produced by humans sucking hard candy lozenges containing zinc gluconate and citric acid demonstrated the probability that the formulation delivered an insignificant amount of the contained zinc as Zn2+. This could account for the negative results of several clinical studies of this lozenge...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Zarembo JE,Godfrey JC,Godfrey NJ

    更新日期:1992-02-01 00:00:00

  • Influence of solid phase and formulation processing on stability of Abbott-232 tablet formulations.

    abstract::Abbott-232 is a chemically stable, highly water soluble non-hygroscopic compound selected for development as a potent uroselective alpha(1A) agonist. An anhydrate, a monohydrate, and an amorphous phase were isolated. The anhydrate was chosen for formulation development based on solid-state characterization. Excipients...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Wardrop J,Law D,Qiu Y,Engh K,Faitsch L,Ling C

    更新日期:2006-11-01 00:00:00

  • Long-term stability of aqueous solutions of luteinizing hormone-releasing hormone assessed by an in vitro bioassay and liquid chromatography.

    abstract::The stability of aqueous solutions of luteinizing hormone-releasing hormone (LHRH) after extended storage at various temperatures was investigated using a newly developed HPLC assay and an in vitro dispersed pituitary cell culture bioassay. Good correlations were obtained between the potency obtained by HPLC and bioas...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Shi YF,Sherins RJ,Brightwell D,Gallelli JF,Chatterji DC

    更新日期:1984-06-01 00:00:00

  • Effect of lipophilicity on the bioavailability of drugs after percutaneous administration by dissolving microneedles.

    abstract::To elucidate drug lipophilicity effects on the bioavailability (BA) of drugs from skin after administration by dissolving microneedles, nine compounds with different lipophilicity indexes (log p value) were formulated into two-layered dissolving microneedles and administered percutaneously to rat skin: desmopressin (D...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Ito Y,Yoshimura M,Tanaka T,Takada K

    更新日期:2012-03-01 00:00:00

  • Indolizines II: search for potential oral hypoglycemic agents.

    abstract::A few 1,2-bis(N-alkylaminomethyl)indolizines, simple indolizinecarboxylic acids, and several 6-alkoxyindolizine-2-carboxylic acids were synthesized and screened as possible oral hypoglycemic agents. The absence of any significant hypoglycemic activity excludes these compounds from the predicted structural lead provide...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: De AU,Saha BP

    更新日期:1975-02-01 00:00:00

  • Investigation of PEG crystallization in frozen PEG-sucrose-water solutions: II. Characterization of the equilibrium behavior during freeze-thawing.

    abstract::Our objective was to characterize, by DSC and XRD, the equilibrium thermal behavior of frozen aqueous solutions containing polyethylene glycol (PEG) and sucrose. Aqueous solutions of (i) PEG (2.5-50% w/w), (ii) sucrose (10% w/v) with different concentrations of PEG (1-20% w/v), and (iii) PEG (2% or 10% w/v) with diffe...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Bhatnagar BS,Martin SM,Teagarden DL,Shalaev EY,Suryanarayanan R

    更新日期:2010-11-01 00:00:00

  • Quantification of the effect of excipients on bioavailability by means of response surfaces III: In vivo--in vitro correlations.

    abstract::This study compares one of the previously studied formulations with commercial amoxicillin capsules. The results indicate that the percentage of the dose absorbed is similar in both formulations; nevertheless, the amoxicillin capsules present a higher absorption rate. The in vivo--in vitro correlations in terms of res...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Llabrés M,Vila JL,Martínez-Pacheco R

    更新日期:1982-08-01 00:00:00

  • Introduction of solvent-accessible surface area in the calculation of the hydrophobicity parameter log P from an atomistic approach.

    abstract::A conventional atomistic approach of estimating molecular hydrophobicity (log P) was improved by taking into account the proximity effect of substituent groups as well as the importance of solute-solvent interaction in the partition phenomena. The new method reassigns atomic parameters when the molecule is fully expos...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Masuda T,Jikihara T,Nakamura K,Kimura A,Takagi T,Fujiwara H

    更新日期:1997-01-01 00:00:00

  • The use of xanthan gum in an ophthalmic liquid dosage form: rheological characterization of the interaction with mucin.

    abstract::The development of an ocular dosage form containing xanthan gum and capable of interacting with mucin in the precorneal area is a challenge. The polymer concentration that can be applied is restricted because of the limited patient acceptability of highly viscous preparations. The precorneal mucin concentration is low...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Ceulemans J,Vinckier I,Ludwig A

    更新日期:2002-04-01 00:00:00

  • Anti-plasticizing effect of amorphous indomethacin induced by specific intermolecular interactions with PVA copolymer.

    abstract::The mechanism of how poly(vinyl alcohol-co-acrylic acid-co-methyl methacrylate) (PVA copolymer) stabilizes an amorphous drug was investigated. Solid dispersions of PVA copolymer, poly(vinyl pyrrolidone) (PVP), and poly(vinyl pyrrolidone-co-vinyl acetate) (PVPVA) with indomethacin (IMC) were prepared. The glass transit...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Ueda H,Aikawa S,Kashima Y,Kikuchi J,Ida Y,Tanino T,Kadota K,Tozuka Y

    更新日期:2014-09-01 00:00:00

  • Development of a CART Model to Predict the Synthesis of Cardiotoxic Daunorubicinol in Heart Tissue Samples From Donors With and Without Down Syndrome.

    abstract::Daunorubicin (DAUN) and doxorubicin (DOX) are used to treat a variety of cancers. The use of DAUN and DOX is hampered by the development of cardiotoxicity. Clinical evidence suggests that patients with leukemia and Down syndrome are at increased risk for anthracycline-related cardiotoxicity. Carbonyl reductases and al...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Hoefer CC,Blair RH,Blanco JG

    更新日期:2016-06-01 00:00:00

  • Influence of non-water-soluble placebo pellets of different sizes on the characteristics of orally disintegrating tablets manufactured by freeze-drying.

    abstract::The present study describes the development of an orally disintegrating tablet containing a non-water-soluble drug delivery system. A model system was applied to evaluate the effect of different-sized particles on tablet characteristics. Cellets were incorporated into tablets prepared by freeze-drying from a 100 mg/mL...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Stange U,Führling C,Gieseler H

    更新日期:2013-06-01 00:00:00

  • Specific interactions in high concentration antibody solutions resulting in high viscosity.

    abstract::The purpose of this work was to investigate the self-associating behavior observed in high concentration monoclonal antibody (MAb1) solutions at pH 6.0. Zeta potential measurements over the pH range (4.0-9.0) showed lower net charges present on the molecule at pH 6.0 and 7.0. The point of zero charge or crossover from...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Yadav S,Liu J,Shire SJ,Kalonia DS

    更新日期:2010-03-01 00:00:00

  • The effects of substituted cyclodextrins on the colloidal and conformational stability of selected proteins.

    abstract::The effects of various types of substituted and nonsubstituted cyclodextrins (CDs) on the physical and colloidal stability of three different proteins were studied to further ascertain the mechanism by which cyclodextrins stabilize proteins. The three proteins examined in this study are the Clostridium difficile Toxoi...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Samra HS,He F,Bhambhani A,Pipkin JD,Zimmerer R,Joshi SB,Middaugh CR

    更新日期:2010-06-01 00:00:00

  • Biochemical investigation of active intracellular transport of polymeric gene-delivery vectors.

    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


    authors: Drake DM,Pack DW

    更新日期:2008-04-01 00:00:00

  • Stereochemistries of geometric isomers of 4-(2-bromo-1,2-diphenylvinyl)phenol, 4-(2-bromo-1,2-diphenyylamine: corrections of the literature.

    abstract::The stereochemistries of geometric isomers of 4-(2-bromo-1,2-diphenylvinyl)phenol, 4-(2-bromo-1,2-diphenylvinyl)anisole, and 2-[p-(2-bromo-1,2-diphenylvinyl)phenoxy]triethylamine were determined by conversion of the phenolic analog to the ethers and subsequent comparison of physical properties with those of 2-[p-(2-ch...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Richardson A Jr,Benson HD,Hite G

    更新日期:1976-10-01 00:00:00

  • Modeling of transmitted X-ray intensity variation with sample thickness and solid fraction in glycine compacts.

    abstract::The previous paper in this series introduced an X-ray diffraction quantitation method for the polymorphic content in tablets made of pure components. Before the method could be transferred, further studies were required to explain the commonly observed X-ray intensity variation in analyzing compacts. The literature ty...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Cao W,Mullarney MP,Hancock BC,Bates S,Morris KR

    更新日期:2003-12-01 00:00:00

  • Comparison of 99mTc-N-pyridoxyl-5-methyltryptophan and 99mTc-N-(3-bromo-2,4,6-trimethylacetanilide)-iminodiace tate as hepatobiliary radiopharmaceuticals in rats.

    abstract::99mTc-N-(3-bromo-2,4,6-trimethylacetanilide)iminodiacetat e (I) and 99mTc-N-pyridoxyl-5-methyl-tryptophan (II) have been described as having optimal properties as hepatobiliary radiopharmaceuticals. This study compared specificity for hepatobiliary excretion, blood disappearance, rates of biliary appearance, and pharm...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Fritzberg AR,Bloedow DC,Eshima D,Johnson DL

    更新日期:1984-12-01 00:00:00

  • Dissolution media for in vitro testing of water-insoluble drugs: effect of surfactant purity and electrolyte on in vitro dissolution of carbamazepine in aqueous solutions of sodium lauryl sulfate.

    abstract::The intrinsic dissolution rate and solubility of carbamazepine was measured in aqueous solutions of sodium lauryl sulfate (SLS) prepared with two different grades of purity, 95 and 99%, and 95% SLS in 0.15 M NaCl to determine the effect of surface-active impurities and electrolytes. Four significant observations resul...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Crison JR,Weiner ND,Amidon GL

    更新日期:1997-03-01 00:00:00

  • Drug Distribution to Human Tissues: Prediction and Examination of the Basic Assumption in In Vivo Pharmacokinetics-Pharmacodynamics (PK/PD) Research.

    abstract::The tissue:plasma partition coefficients (Kp ) are good indicators of the extent of tissue distribution. Therefore, advanced tissue composition-based models were used to predict the Kp values of drugs under in vivo conditions on the basis of in vitro and physiological input data. These models, however, focus on animal...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Poulin P

    更新日期:2015-06-01 00:00:00

  • Facile synthesis of glycol metabolites of phenethylamine drugs.

    abstract::High yields of potential glycol metabolites of p-synephrine, epinephrine, octopamine, and normacromerine can be obtained from the readily available monosubstituted and disubstituted acetophenones. The general procedure involves alpha-bromination followed by displacement with acetate ion and reduction with lithium alum...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Holshouser MH,Kolb M

    更新日期:1986-06-01 00:00:00

  • Dequaternization of curare bases with sodium thiophenoxide and ethanolamine.

    abstract::To prepare (+)-tubocurine and O,O-dimethyl-(+)-tubocurine, the commonly used dequaternization procedures with sodium theophenoxide and ethanolamine were investigated. The quaternary compounds were (+)-tubocurarine chloride and the chloride and iodide salts of O,O-dimethyl-(+)-chondocurarine. The results obtained with ...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Naghaway JA,Soine TO

    更新日期:1978-09-01 00:00:00

  • Radioimmunoassay for terfenadine in human plasma.

    abstract::A radioimmunoassay procedure was developed for the antihistamine terfenadine (alpha[4-(1,2-dimethylethyl)phenyl]-4-(hydroxydiphenylmethyl)-1-piperidinebutanol). The keto analog of terfenadine was converted to its O-carboxymethyloxime derivative, which was conjugated to bovine thyroglobulin by a mixed anhydride techniq...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Cook CE,Williams DL,Myers M,Tallent CR,Leeson GA,Okerholm RA,Wright GJ

    更新日期:1980-12-01 00:00:00

  • In vivo and ex vivo evaluation of a multi-particulate composite construct for sustained transbuccal delivery of carbamazepine.

    abstract::Carbamazepine (CBZ) is a leading molecule in the management of epilepsy. Surveys have revealed that a sufficient lack of therapeutically efficient CBZ transbuccal formulation exists. Therefore, this investigation was directed toward designing multiparticulate composite construct (MCC) for the transbuccal delivery of C...

    journal_title:Journal of pharmaceutical sciences

    pub_type: 杂志文章


    authors: Adeleke OA,Choonara YE,Du Toit LC,Pillay V

    更新日期:2014-04-01 00:00:00