Practical kinetics I: Quantitation of barbiturate stability by TLC.

The purpose of this work was the application of established techniques to the quantitation of stability investigations of liquid formulations as well as in solution kinetic studies. The process consists of streaking aliquots of reaction solution on TLC plates, development, elution, and analysis of the substances in the eluate. Several barbiturates were investigated regarding their decomposition at elevated temperatures. Reasonable correlation is noted between obtained rate constants and literature data. This technique represents a utilitarian approach to stability screening of compounds in solution, aqueous or otherwise, where chromatographic separation and analytical methodology for the pure compound are available.