𝔖 Bobbio Scriptorium
✦   LIBER   ✦

The assay and absorption kinetics of oral theophylline−7-acetic acid in the human

✍ Scribed by S. Sved; I. J. McGilveray; N. Beaudoin


Publisher
John Wiley and Sons
Year
1981
Tongue
English
Weight
369 KB
Volume
2
Category
Article
ISSN
0142-2782

No coin nor oath required. For personal study only.

✦ Synopsis


Abstract

A sensitive and specific method for the estimation of theophylline−7‐acetic acid in plasma by high performance liquid chromatography is described. Acidified plasma is extracted with chloroform‐n‐butanol (85: 15), back extracted with phosphate buffer (0.5 moll^−1^, pH 6.5), and finally the acidified aqueous phase extracted again with chloroform‐butanol. After evaporation of the extract the residue is redissolved in the chromatographic mobile phase (hexane‐dichloromethane‐ethanol‐acetic acid, 10:86: 3:1) and chromatographed on silica gel. The method was used to follow the plasma theophylline‐7‐acetic acid concentrations in two volunteers after single oral doses of 1.0 g of the drug. The results confirm previous reports, based on urine data and on plasma data following intravenous administration, that the drug is poorly absorbed (apparent bioavailability of 1 and 2 per cent), rapidly eliminated (half‐life of 1.0 and 2.4 h) and not converted to theophylline.


📜 SIMILAR VOLUMES


Kinetics and mechanism of the oxidation
✍ Kalyan K. Sen Gupta; Biswajit Pal; Pratik K. Sen 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 200 KB 👁 1 views

The kinetics of oxidation of some neutralized ␣-hydroxy compounds such as glycolic (GA), lactic (LA), ␣-hydroxyisobutyric(IB), mandelic (MA), atrolactic (AL), and benzilic (BA) acids by tetrachloroaurate(III) have been studied. The substrates are oxidized to give formaldehyde, acetaldehyde, acetone,

A study of aminolevulinic acid-induced p
✍ Vaidyanathan, Vijay V.; Rastegar, Sohi; Fossum, Theresa W.; Flores, Patricia; va 📂 Article 📅 2000 🏛 John Wiley and Sons 🌐 English ⚖ 160 KB 👁 2 views

Background and Objective: 5-Aminolevulinic acid-induced protoporphyrin IX is a promising photosensitizer that could enhance the spectroscopic contrast between normal and diseased oral tissues. Knowledge of the pharmacokinetics and effects on tissue type are important for diagnostic and therapeutic p

ChemInform Abstract: Kinetics and Mechan
✍ Jeffrey S. Nicoson; Dale W. Margerum 📂 Article 📅 2010 🏛 John Wiley and Sons ⚖ 30 KB 👁 2 views

## Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable v

Kinetic study on the esterification of g
✍ Shih-Yow Huang; Hsiao-Li Chang 📂 Article 📅 1999 🏛 Wiley (John Wiley & Sons) 🌐 English ⚖ 169 KB 👁 2 views

Surfactant-coated lipase (SCL) was prepared by coating the surface of Candida cylindracea lipase with the non-ionic surfactant, Span 85. SCL catalyzed the esteriücation of geraniol and acetic acid. The ester product, geranyl acetate, is an important component of ýavor and fragrance compounds. The SC

The solvent effects in the reactions of
✍ Wiktor Bukowski 📂 Article 📅 2000 🏛 John Wiley and Sons 🌐 English ⚖ 184 KB 👁 2 views

Kinetics of the reaction of acetic acid with epichlorohydrin in the presence of chromium(III) acetate in butan-1-ol solution have been studied. The partial reaction orders with respect to reagents were found. The reactions were of first-order with respect to both epichlorohydrin and catalyst and zer