Modular testing

The performance of an HPLC system can be evaluated by examining the key functions of the various modules that comprise the system, followed by holistic testing that challenges the performance of the HPLC components as an integrated system. The holistic testing is commonly referred to as the performance qualification (PQ). The holistic test can be as simple as running a frequently used HPLC method in the laboratory. Modular testing of various components, which is... 

If a system comprises several modules, it is recommended that system tests be performed for parameters that are affected by multiple modules (holistic testing) rather than performing tests module by module (modular testing). Individual module tests should be performed if the parameter is affected by that module only (e.g., the wavelength accuracy of an HPLC variable-wavelength detector or the temperature accuracy of a column compartment). 

If the sy.stem does not perform as expected, individual modules may be interchangeably used to identify the source of the system problem, which means modular testing is recommended for troubleshooting purposes. 

Muller, A., Drese, K., Gnaser, H., Hampe, M., Hessel, V, Lowe, H., Schmitt, S., Zapf, R., Fast preparation and testing methods using a micro-structured modular reactor for parallel gas phase catalyst screening, Catal. Today 81 (2002) 377-391. 

Since carbohydrates constitute an inexpensive and highly modular chiral source for preparing chiral ligands," Claver et al. have reported the use of a series of thioether-phosphite" and thioether-phosphinite furanoside ligands" in the test palladium-catalysed allylic substitution reaction. In the first type of ligand, a systematic variation of the donor group attached to the carbon atom C5 indicated that the presence of a bulky phosphite functionality had a positive effect on the enantioselectivity. Indeed, the enantioselectivity was controlled mainly by the phosphite moiety. This was confirmed by the use of a ligand... 

Bundesinstitut fiir Gesundheitlichen Verbraucherschutz und Veterinarmedizin, Official Collection of Test Methods According to 35 LMBG (Law of Food and Commodities), edited Beuth Verlag, Berlin, 1999, Modular Multi Method L 00.00-34. 

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