Reliable low-cost capillary electrophoresis device for drug quality control and counterfeit medicines

Abstract

The proportion of counterfeit medicines is dramatically increasing these last few years. According to numerous official sources, in some pharmaceutical wholesalers in African countries, the proportion has reached 80%. Unfortunately, this situation is far to be improved due to lack of suitable analytical equipment allowing rapid actions of the Regulatory Agencies based on scientific consideration, at affordable cost and all over the drug supply chain. For that purpose, a network group considered that mater by building a low-cost original capillary electrophoresis (CE) equipment equipped with a new deep UV detector based on LED technology. The generic conditions for analysis were investigated: capillary zone electrophoresis (CZE) performed at acidic pH for basic drug molecules (i.e., quinine, highly used as the last antimalarial rampart), basic pH for compounds such as furosemide (a common diuretic drug) and at neutral pH for a well known antibiotic combination, trimethoprim/sulfamethoxazol. To evaluate the ability of the CE equipment for quantification, a full validation and a method comparison study were carried out for the CZE method dedicated to quinine determination. The validation involved the use of accuracy profile and total error concept to monitor the adequacy of the results obtained by the new prototype. The method comparison was based on the Bland and Altman approach by comparing results obtained by the low-cost CE and a conventional set-up. Subsequent validation studies were realized with neutral and acidic drug molecules, each focusing on a single concentration level calibration curve in order to maintain as low as possible the expenses due to reagents and thus the cost of analysis, as important advantages of CE for drug quality control.