Development of a capillary electrophoresis method for the determination of the chiral purity of dextromethorphan by a dual selector system using quality by design methodology.

Dextromethorphan is a centrally acting antitussive drug, while its enantiomer levomethorphan is an illicit drug with opioid analgesic effects. As capillary electrophoresis has been proven as an ideal technique for enantiomer analysis, the present study was conducted in order to develop a capillary electrophoresis-based limit test for levomethorphan. The analytical target profile was defined as a method that should be able to determine levomethorphan with acceptable precision and accuracy at the 0.1 % level. From initial scouting experiments, a dual selector system consisting of sulfated ß-cyclodextrin and methyl-α-cyclodextrin was identified. The critical process parameters were evaluated in a fractional factorial resolution IV design followed by a central composite face-centered design and Monte Carlo simulations for defining the design space of the method. The selected working conditions consisted of a 30/40.2 cm, 50 µm id fused-silica capillary, 30 mM sodium phosphate buffer, pH 6.5, 16 mg/mL sulfated ß-cyclodextrin, and 14 mg/mL methyl-α-cyclodextrin at 20°C and 20 kV. The method was validated according to ICH guideline Q2(R1) and applied to the analysis of a capsule formulation. Furthermore, the apparent binding constants between the enantiomers and the cyclodextrins as well as complex mobilities were determined to understand the migration behavior of the analytes.

[The role of German official medicines control laboratories in combating counterfeit medicines]. / Die Rolle der deutschen amtlichen Arzneimitteluntersuchungsstellen bei der Bekämpfung von Arzneimittelfälschungen.

An official medicines control laboratory (OMCL) provides an important contribution to combat counterfeit and illegal medicines. The OMCL supports the competent authorities in controlling the quality of authorised medicinal products in the legal supply chain. For detecting counterfeit medicines in the legal supply chain, a risk-based approach in choice of products is conducted. Furthermore, the OMCL analyses suspicious medicines from the illegal supply chain for any other authority. The chemical analysis of a suspicious sample is needed to identify such a sample as a counterfeit medicine. The analytical results are fundamental for the evaluation of the legal status of the product and for the assessment of it's inherent hazard to public health. The global market of illegal medicines is rapidly changing. Therefore a good national and international working liaison and co-operation between laboratories and authorities is obligatory to protect public health. The OMCL provides important knowledge of new trends in counterfeit and illegal medicines. Hence, it is an essential part in surveillance of medicinal products. The efficient networking enables prompt official interventions. Thus, risks for the public health by substandard medicines were reduced. Beside the chemical analysis, the OMCL can help to raise public awareness about counterfeit and illegal medicines. In Germany, the risk of counterfeit medicines reaching patients through the legal supply chain is still low, but the possibility cannot be ignored.