Abstract：
:First-order rate constants (k) were determined for the hydrolysis of ceftazidime in the pH range of 0.5 to 8.5 at 45, 55, and 65 degrees C by a stability-indicating HPLC assay. In the absence of buffer effects, the pH-rate expression was k = kH1f1(aH+) + kH2f2(aH+) + kH3f3(aH+) + kSf3 + kOHf3(aOH-), where KH and KOH are the catalytic rate constants for the activity of hydrogen (aH+) and hydroxyl (aOH-) ions, respectively, and kS is the rate constant for spontaneous hydrolysis. The fractions of ceftazidime in various stages of dissociation (f1, f2, and f3) were calculated from kinetically determined apparent Ka values of 2.03 x 10(-2) and 4.85 x 10(-5). Catalytic constants (kcat) were calculated for formate, acetate, phosphate, and borate buffers, which accelerated hydrolysis. Each of the rate constants (kH1, kH2, kH3, kS, kOH, and kcat) were described as a function of temperature with calculated A and E values in the Arrhenius equation, kT = Ae-E/RT. Ceftazidime hydrolysis rate constants (k) were calculated as a function of pH, temperature, and buffer by combining the pH-rate expression with the buffer contributions calculated from kcat values and the temperature dependencies. These equations and their parameter values successfully calculated 95 of 104 experimentally determined rate constants with errors of < 10%. Maximum stability was observed in the relatively pH-independent region from 4.5 to 6.5. Hydrolysis rate constants at 30 degrees C were predicted and experimentally verified for four ceftazidime solutions, three of which (pH 4.4 acetate buffer and pH 5.5 and 6.5 phosphate buffers) maintained 90% of their initial concentration for approximately 1.5 days.
journal_name
J Pharm Scijournal_title
Journal of pharmaceutical sciencesauthors
Zhou M,Notari REdoi
10.1002/jps.2600840504subject
Has Abstractpub_date
1995-05-01 00:00:00pages
534-8issue
5eissn
0022-3549issn
1520-6017pii
S0022-3549(15)49805-3journal_volume
84pub_type
杂志文章abstract：:Nonviral, plasmid-based therapeutics are a new class of pharmaceutical agents that offer the potential to cure many diseases that are currently considered untreatable. While nonviral vectors have shown promise in clinical trials, their physical instability in liquid formulations represents a major barrier to the devel...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章,评审
doi：10.1002/(SICI)1520-6017(200003)89:3<289::AID-JPS1>
更新日期：2000-03-01 00:00:00
abstract：:The recently introduced four-parameter extended Hansen approach was used to study the solubility of p-hydroxybenzoic acid and methyl p-hydroxybenzoate in 32 and 35 individual solvents, respectively. The results are compared with those for benzoic acid in 40 solvents. Seventeen of the thirty-two or 53% of the calculate...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600730211
更新日期：1984-02-01 00:00:00
abstract：:Various complex mechanisms and their multifactorial pathways decisively provoke low-grade local and systemic inflammation in β-cells of pancreatic islets and peripheral tissues to induce β-cells' dysfunction and apoptosis, insulin resistance, and ultimately, overt type 2 diabetes mellitus (T2DM). Conventional antidiab...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章,评审
doi：10.1002/jps.23057
更新日期：2012-05-01 00:00:00
abstract：:Drug stability studies are expensive and time consuming. Multiple batches are studied to ensure that a product will consistently remain within specifications for its entire expiration dating period. Some of these studies involve the same drug products in similar packages or in multiple strengths. Application of sound ...
journal_title：Journal of pharmaceutical sciences
pub_type： 指南,杂志文章
doi：10.1002/jps.2600841112
更新日期：1995-11-01 00:00:00
abstract：:The effect of dietary polyphenols on the intestinal glucuronidation and absorption of a model phenolic drug, alpha-naphthol (alpha-NA), was studied in isolated rat small intestine. (-)-Epicatechin significantly inhibited the glucuronidation of alpha-NA. Chrysin, (-)-epigallocatechin galleate (EGCG), and quercetin decr...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.20146
更新日期：2004-09-01 00:00:00
abstract：:An HPLC method for determining total pyridoxal from plasma was developed for a relative bioavailability comparison of two oral vitamin B6 (pyridoxine HCl) preparations. After cleavage of the pyridoxal-5-phosphate with the acid phosphatase enzyme, the total pyridoxal was determined by HPLC. Pyridoxal was separated on a...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600820921
更新日期：1993-09-01 00:00:00
abstract：:A sensitive, specific, high-performance liquid chromatographic procedure was developed for the measurement of plasma tiflamizole levels. Acidic plasma samples were extracted with three volumes of ether. The ether extracts were combined and evaporated to dryness. The residue was dissolved in acetonitrile, washed with h...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600731245
更新日期：1984-12-01 00:00:00
abstract：:Results of studies carried out in rats for model compounds, D-(-) mandelic acid, benzoylformic acid, and some of their para-alkylated homologs, showed that their biological half-lives determined from the elimination phase of urinary excretion data were longer than those determined from the elimination phase of blood l...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600650920
更新日期：1976-09-01 00:00:00
abstract：:Methods for the determination of diphenoxylate hydrochloride and atropine sulfate combinations in solutions and powdered tablet composites are presented. A semiautomated assay for diphenoxylate hydrochloride in individual tablets (content uniformity) also is presented. The USP XIX assays for these products are cumbers...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600661113
更新日期：1977-11-01 00:00:00
abstract：:The purpose of this investigation was to determine the effect of body temperature on the pharmacodynamics (convulsant activity) of pentylenetetrazol (PTZ). Rats received an iv infusion of PTZ until the onset of maximal seizures, at which time samples of cerebrospinal fluid (CSF), brain, and blood (for serum) were obta...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600801005
更新日期：1991-10-01 00:00:00
abstract：:Thymoquinone (TQ) is the main bioactive component isolated from Nigella sativa essential oil and seeds and has been used for the treatment of inflammations, liver disorders, arthritis, and is of great importance as a promising therapeutic drug for different diseases including cancer. This paper reports the first exper...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.23138
更新日期：2012-07-01 00:00:00
abstract：:The physical stability of an immunoglobulin G4 monoclonal antibody (mAb) upon dilution into intravenous (i.v.) bags containing 0.9% saline was examined. Soluble aggregates and subvisible particles were observed by size-exclusion high-performance liquid chromatography (SE-HPLC) and light obscuration when formulated wit...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.23224
更新日期：2012-10-01 00:00:00
abstract：:In recent years, computational methods have garnered much attention in protein engineering. A large number of computational methods have been developed to analyze the sequences and structures of proteins and have been used to predict the various properties. Antibodies are one of the emergent protein therapeutics, and ...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章,评审
doi：10.1016/j.xphs.2020.01.011
更新日期：2020-05-01 00:00:00
abstract：:Various multiparticulate dissolution models that assume a log-normal particle-size distribution are fitted by nonlinear least-squares regression to data from the dissolution of micronized glyburide. Estimates of parameters describing the effective initial particle-size distribution are obtained, together with estimate...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600660603
更新日期：1977-06-01 00:00:00
abstract：:Solvent-induced 3 frameworks (the monohydrate, methanol solvate, and dimethyl formamide [DMF] solvate) of an anticancer drug, 7-ethyl-10-hydroxycamptothecin (SN38), were constructed. The crystal structures of the 3 pseudopolymorphs were characterized by single-crystal X-ray diffraction technique for the first time. Cr...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1016/j.xphs.2017.03.020
更新日期：2017-10-01 00:00:00
abstract：:Alginate-based polyelectrolyte complexes (PECs) and hydrogel were engineered as platforms for local bevacizumab (BVZ) therapy. This study provides deep comprehension on the microstructures of such systems, and their correlation with drug-release patterns. PECs and hydrogel were characterized using Fourier transform in...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1016/j.xphs.2018.11.038
更新日期：2019-04-01 00:00:00
abstract：:Alkyl 2-imidazolyl disulfide compounds are novel antitumor agents, one of which is currently being evaluated in Phase I clinical trials. These molecules contain an unsymmetrical disulfide fragment, the lipophilic and electronic contributions of which are still not defined in the literature. Lipophilicity, ionization, ...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.10112
更新日期：2002-07-01 00:00:00
abstract：:Cyclosporin A (CyA) interacts with lipid membranes. Binding reaction and membrane location of CyA and analogs were examined with 2H-NMR, high-sensitivity isothermal titration calorimetry (ITC), and CD spectroscopy. Effects of CyA and charged analogs on the phosphocholine head group and on the membrane interior were in...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.10071
更新日期：2002-03-01 00:00:00
abstract：:Biodegradable, dextran-based ion-exchange microspheres (IE-MS) have been used for localized delivery of anticancer drugs and chemosensitizers. Because of their hydrophilic nature, the IE-MS release their payload quickly. The purpose of this work was to develop an IE-MS system that could provide a broad range of releas...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/(SICI)1520-6017(200006)89:6<807::AID-JPS13
更新日期：2000-06-01 00:00:00
abstract：:A simple and sensitive assay for quantitating 9-methyl-3-(1H-tetrazol-5-yl)-4H-pyrido[1,2-a]pyrimidin-4-one (1; BMY 26517) in human plasma was developed using high-performance liquid chromatography with fluorescence detection. The method involves precipitation of protein and reversed-phase chromatography. The method i...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600761216
更新日期：1987-12-01 00:00:00
abstract：:The reaction kinetics of blue tetrazolium with selected arylhydrazines were investigated under pseudo-first-order conditions. The reaction rate constants were obtained at various temperatures, and the enthalpy (8.4-11.2 kcal/mole) and entropy (-38--45 eu) of activations were calculated. A Hammett plot yielded a straig...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600670714
更新日期：1978-07-01 00:00:00
abstract：:The Setschenow constant, K(salt), of a nonelectrolyte in a NaCl solution is shown to be related to the logarithm of its octanol-water partition coefficient, log K(ow), determined by K(salt) = A log K(ow) + B, where K(ow) is the octanol-water partition coefficient of the solute and the coefficients A and B are constant...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/1520-6017(200012)89:12<1620::aid-jps13>3.0
更新日期：2000-12-01 00:00:00
abstract：:Central-nervous-system, physiologically based pharmacokinetic (PBPK) models predict exposure profiles in the brain, that is, the rate and extent of distribution. The current work develops one such model and presents improved methods for determining key input parameters. A simple linear regression statistical model est...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1016/j.xphs.2015.12.005
更新日期：2016-02-01 00:00:00
abstract：:Racemic and homochiral sodium ibuprofen were characterized by thermal analysis and powder X-ray diffractometry. The melting point phase diagram was constructed and thermodynamic calculation was performed. In contrast to racemic ibuprofen, which is a racemic compound, racemic sodium ibuprofen forms both a racemic congl...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.10393
更新日期：2003-07-01 00:00:00
abstract：:Small particles of two steroids, cholesteryl acetate and beta-sitosterol, were prepared by the following technique. The steroid was dissolved in an organic solvent, which was emulsified in water in the presence of surfactant, thus giving a water-continuous emulsion. As the organic solvent was evaporated, the steroid p...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600820608
更新日期：1993-06-01 00:00:00
abstract：:A sensitive (10 ng/mL) and specific high-performance liquid chromatographic (HPLC) assay, with electrochemical (EC) detection, for the geometric isomers of 3-hydroxy-N-(2-phenyl-2-(2-thienyl)ethenyl-5-(trifluoromethyl)benzo(b) thiophene-2-carboxamide in dog and human plasma has been developed. Both isomers strongly ab...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600771014
更新日期：1988-10-01 00:00:00
abstract：:The binding of Cu2+ and Ni2+ to bovine, dog, and human serum albumin has been studied by the 35Cl NMR probe technique. The number of primary copper sites were estimated to be 1.3 for human serum albumin, 3.1 for bovine serum albumin, and 6.6 for dog serum albumin. A similar number of primary nickel sites was determine...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600740116
更新日期：1985-01-01 00:00:00
abstract：:The degradation kinetics of moricizine hydrochloride (1) were examined over a pH range of 0.6 to 6.0 at an ionic strength of 0.3 and 60 degrees C. The disappearance of intact 1 was followed by a stability-indicating HPLC assay. The degradation products, which had approximate solubilities of less than 100 micrograms/mL...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600810625
更新日期：1992-06-01 00:00:00
abstract：:Preliminary studies indicate that it may be possible to differentiate the effects of a nephrotoxic substance from those of diuretic agents by the measurement of both urine and plasma osmolarity. The nephrotoxic substance, mercuric chloride, decreases urinary osmolality and increases plasma or serum osmolality. The diu...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600660411
更新日期：1977-04-01 00:00:00
abstract：:The granule strength (crushing load) of lactose granulated with 1-9% povidone was measured initially and at intervals during a 1-year period. The granule strengths of dibasic calcium phosphate dihydrate granulated with various concentrations of starch and povidone were measured. The axial and radial tensile strengths ...
journal_title：Journal of pharmaceutical sciences
pub_type： 杂志文章
doi：10.1002/jps.2600720513
更新日期：1983-05-01 00:00:00
