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The goal of the present study was to separate a set of benzodiazepines, namely bromazepam, oxazepam, nitrazepam, chlordiazepoxide, flunitrazepam, lormetazepam and diazepam by analytical scale HPLC and CZE. The both methods for separation of these seven compounds from the 1,4-benzodiazepine group were optimized and compared. LODs and LOQs were determined under the optimized conditions in the both methods. The corresponding LOD and LOQ values are approximately three orders of magnitude lower in HPLC than in CZE. As expected, elution order was found to be different for the both techniques. As a result of a critical collation of all the parameters considered, RP-HPLC was found to be more suitable for determination of the set of benzodiazepines. A real sample analysis was performed under optimized conditions to demonstrate applicability of the proposed analytical methods. (doi: 10.5562/cca1738)

In recent years enantioseparation of both active pharmaceutical ingredients and bio molecules such as amino acids became more and more necessary because in most cases the two stereo forms exhibit different pharmacological effects. This article deals with the chiral separation of dansylated amino acids by ligand-exchange capillary electrophoresis using L-phenylalaninamide, L-lysine and L-threonine as chiral selectors. Experiments with different central metal ions such as Cu(II), Co(II), Cd(II), Ni(II) and Zn(II) were carried out. Optimal conditions were found out by studying the effect of the pH and the selector molarity on the chiral resolution. Best separation was obtained for the Cu(II)/L-lysine complex, showing a chiral resolution up to 17 for Dns-DL-Met. (doi: 10.5562/cca1762)

A novel methodology for the synthesis of sulfo- and oxy-modified amino acid analogues of arginine (Arg) has been developed using both conventional and polymer assisted synthesis from ready available amino acid precursor. Introduction of guanidine group was made also by the MWA synthesis. The in vitro inhibitory effect of the amino acid analogues on the growth of murine erythroleukemia cells, clone F4N in culture was also studied. (doi: 10.5562/cca1780)