Journal of Chromatograhy A, 2021
Authors: Thi Kieu Tiên Do, Marco Schmid, Manjusha Phanse, Akshay Charegaonkar, Hanspeter Sprecher, Markus Obkircher & Eike Reich
Abstract
The use of chromatographic methods in routine analysis includes System Suitability Tests (SST). This paper presents a novel approach to SST in HPTLC, which allows qualification of the entire RF range of an HPTLC plate independently of the samples. It is based on the Universal HPTLC mix (UHM), a pre-defined mixture of eight reference substances: guanosine, sulisobenzone, thymidine, paracetamol, phthalimide, 9-hydroxyfluorene, thioxanthen-9-one, and 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol, selected to cover a broad range of polarities and functional groups. The chromatographic behavior of the UHM was evaluated for 20 different mobile phases on Silica gel 60 F>sub>254. At least three constituents were baseline separated. In a collaborative trial with four laboratories the reproducibility of RF values for three representative mobile phases, was found to be within a confidence interval of 0.040
RF units. The response characteristics of the UHM were assessed with respect to changes in chromatographic conditions, such as variation of the relative humidity, improperly employed saturation, or mistakes in the preparation of the mobile phase. Based on the
RF values of the individual constituents significant responses were found for most changes. This qualifies the UHM for use in SST.
https://doi.org/10.1016/j.chroma.2020.461830