A novel approach for the development of the first universal HPTLC mixture (UHM) to be used in system suitability tests was developed by the research team at CAMAG Switzerland in collaboration with Anchrom Enterprises (I) Pvt Ltd, and Sigma Aldrich Chemie GmBH, Switzerland.
System Suitability Test:
System Suitability Testing (SST) is done to assess whether the HPTLC chemical analysis method is working as per its intended purpose. In a system suitability testing process, a single reference or a mixture of reference samples is taken and analyzed with the selected chromatographic method. Now the results of these tests are compared with the acceptance criteria that would qualify the chromatographic system for its performance.
As per the European and US Pharmacopoeias, the principal criteria for an HPTLC analysis system to be qualified is that the reference substances selected have similar Rf values and are separable.
Universal HPTLC Mix (UHM):
A universal mixture for use in system suitability tests for HPTLC was developed. A total of 8 reference standards covering a broad range of polarities and functional groups were used in the development of the mixture.
Chromatographic behavior of the UHM:
The chromatographic behavior of the UHM was evaluated using 20 different mobile phases on Silica Gel F254 and a baseline separation of at least 3 different constituents was done. Additionally, testing carried out in collaboration with four different labs showed the Rf value of the mobile phase was within the confidence interval of 0.040 Rf units.
The mixture was subjected to various conditions viz. changes in Relative Humidity, improper saturation, deliberate mistakes in the preparation of the mobile phase.
It was observed that significant responses were found for most of the varied conditions based on the Rf value.
With reference to the various tests that were carried out for the qualification of the Universal HPTLC mixture, it can be concluded that the novel Universal HPTLC Mixture can be used for the System Suitability Testing.