Reference

Separation and spectrophotometric determination of theophylline and hydroxyethyltheophylline in a pharmaceutical sirup

Separation and spectrophotometric determination of theophylline and hydroxyethyltheophylline in a pharmaceutical sirup. De Fabrizio, Fabrizio (Control Pharm. Lab., Saphar Lab. (PTY) Ltd., Johannesburg, S. Afr.). J. Pharm. Sci., 67(4), 572-3 (English) 1978. CODEN: JPMSAE. ISSN: 0022-3549. DOCUMENT TYPE: Journal CA Section: 64 (Pharmaceutical Analysis) A simple chromatog. procedure was developed for the sepn. and detn. of theophylline (I) [58-55-9] and hydroxyethyltheophylline (II) [519-37-9]. An aliquot of dild. sirup was pipetted into a chromatog. column contg. a strong anion-exchange resin, which retains I and allows the hydroxyethyl deriv. to pass through it. I was subsequently eluted with 1N HCl and detd. by difference spectrophotometry at 284 nm; its deriv. was detd. at 272 nm.

The cobalt reaction of barbital

The cobalt reaction of barbital. Schmidt, Fredulf (Med. Akad., Luebeck, Ger.). Dtsch. Apoth.-Ztg., 118(12), 443-4 (German) 1978. CODEN: DAZEA2. ISSN: 0011-9857. DOCUMENT TYPE: Journal CA Section: 64 (Pharmaceutical Analysis) Using isobutylamine [78-81-9] as the alkalizing agent for the alk. Co test for barbiturates, the test was made more sp. In addn. to barbiturates only phenytoin [630-93-3], ethosuximide [77-67-8], pyrithyldione [77-04-3] and theophylline [58-55-9] gave pos. reactions. Chlortalidone [77-36-1], thiamazole [60-56-0], tolazolin [59-98-3], and 4-nitrophenol [100-02-7] reacted with different colors (blue gray, blue green, blue green and yellow, resp.). A group of 102 drugs gave neg. tests making the modified test more sp.