Determination of Phenytoin in Serum in the Presence of Barbiturates, Sulthiame and Ethosuximid by Thin-Layer Chromatography

Abstract

Phenytoin was determined quantitatively and specifically by a method suitable for routine use. Extracts of 1 ml serum were applied to silica gel plates with a dispensing syringe. After development, the plates were dipped into staining reagents and faded by high humidity and heat. The uniformity of the plates ensures well defined spots with constant RF values. In routine conditions, 0.5–40μg pnenytoin could be quantified corresponding to serum concentrations in the range 0–20 m/gl, the S. D. being 1 mg/l. The determination could be completed in 2 1/2 hours.

Key Words:

• Anti-epileptics
• barbiturates
• diphenylhydantoin
• phenytoin
• thin-layer Chromatography