Approach to develop a standardized TLC-DPPH• test for assessing free radical scavenging properties of selected phenolic compounds.

Research paper by Łukasz Ł Cieśla, Jakub J Kryszeń, Anna A Stochmal, Wiesław W Oleszek, Monika M Waksmundzka-Hajnos

Indexed on: 04 Jul '12Published on: 04 Jul '12Published in: Journal of Pharmaceutical and Biomedical Analysis


TLC-DPPH(•) test belongs to a group of frequently performed assays aimed at detection of compounds with desired activity (effect directed analysis). Despite its popularity a standard procedure has not been elaborated so far causing difficulties in comparing results obtained in different laboratories. Thus the aim of the presented research was an approach to develop a standardized procedure for assessing free radical scavenging properties of plant polyphenols. It was observed that specifically positive adsorbent (silica gel) strengthened the observed result of radical-antioxidant reaction, while polar bonded stationary phase CN-silica weakened it. Based on the observed results it was concluded that the TLC-DPPH(•) assay should be preferably performed on the surface of non-specific adsorbents (e.g.: RP-18) with the use of n-hexane for DPPH(•) dissolution. It is also proposed to document the results every 5 min after staining, as they change in time.