Applicability of the Universal Mixture for describing system suitability and quality of analytical data in routine normal phase High Performance Thin Layer Chromatography methods.

The Universal HPTLC Mixture (UHM) consists of eight substances (guanosine, sulisobenzone, thymidine, paracetamol, phthalimide, 9-hydroxyfluorene, thioxanthen-9-one, and 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol) and yields separated zones over the whole R range for a multitude of developing solvents. Therefore, it could be used in a generic system suitability test (SST) as well as for the verification of quality of HPTLC data. In this work, changes caused by ±10% variation of the volume fractions of the developing solvent components were tested on three developing solvents, to investigate the R shifts of the UHM zones in comparison to established SSTs and results described for test samples in selected pharmacopeia monographs for identification of herbal drugs.