title: An improved benzophenone procedure for the micro-determination of 5,5-diphenylhydantoin in blood.
abstract: A micro-modification of the benzophenone procedure proposed by Wallace for the determination of 5,5-diphenylhydantoin in blood is described which does not require specialised glassware and avoids the interferance caused by chloroform. In the new procedure 5,5-diphenylhydantoin is extracted from blood with 1,2-dichloroethane, returned to alkali, washed with n-heptane, and oxidised with permanganate in small teflon lined screw capped test tubes containing a layer of n-heptane. The absorbance of the oxidation product (benzophenone) is measured spectrophotometrically on an expanded scale using semi micro cuvettes. The method requires 100-200 mul sample and has a detection threshold of less than 0.1 mg/100 ml.
mesh_terms: D001577:Benzophenones; D006801:Humans; D008722:Methods; D008832:Microchemistry; D010084:Oxidation-Reduction; D010672:Phenytoin / Q000097:blood*; D010949:Plasma / Q000032:analysis; D013696:Temperature; D013997:Time Factors
chemical_list: D001577:Benzophenones; D010672:Phenytoin