Ülkü Dilek Uysal

This article presents a newly developed capillary gel electrophoresis (CGE) using dynamic coating with hydroxyethylcellulose methodology for the separation of fourteen standard DNA fragments and determination of RAPD-PCR products after a PCR purification clean-up procedure for certain Salvia (sage) species. The developed CGE was successfully applied to the RAPD products of ten different Turkish Salvia (sage) species (Salvia bracteata, S. candidissima, S. ceratophylla, S. dichroantha (endemic), S. forskahlei, S. fruticosa, S. sclarea, S. tomentosa, S. verticillata, and S. viridis). These medicinal plants exhibit a wide range of Turkish flora. The CGE results were compared with those by the slab gel electrophoresis (SGE). The present study offers an alternative CGE method to SGE for the effective separation and evaluation of RAPD-PCR products. This CGE has certain advantages to SGE on the viewpoint of requiring smaller amount of sample and solvent, higher resolution and speed, easier automation, higher sensitivity, and online detection. DNA analysis in Salvia species can help further understanding of their biological functions. In this study, a phylogenetic relationship was analysed by SGE. S. fruticosa and S. dichroantha are genetically the most distant species, and S. bracteata and S. fruticosa are the the most similar species.

A validated capillary electrophoresis method for the determination of parabens-methyl, ethyl, propyl, and butyl is described. The optimum results were obtained by the use of a run buffer containing 20 mM borate buffer (pH 9.0) with 10% methanol and by applying a voltage of 20 kV, a low hydrodynamic injection of 10 s, and detecting the signals at 200 nm. Moxifloxazin was used as an internal standard. All parabens were separated within 10 min. The method showed a good repeatability, linearity, and sensitivity. It was applied to the determination of parabens in pharmaceutical and certain cosmetic products.

A capillary electrophoretic method for the determination of cetirizine is described in this study. The method was developed by using a running buffer consisting of 10 mM of 10% methanol with pH 8.5, employing a fused silica column with a total length of 85 cm, an effective length of 65 cm, and internal diameter of 75 µm. 28 kV were applied, which produced signals that were detected at 200 nm. Under these conditions, cetirizine and phenobarbital sodium as an internal standard appeared at 6.7 and 8.9 minutes, respectively. The limits of detection and quantification were found to be 5.45×10⁻⁶ M and 1.60×10⁻⁵ M, respectively. The repeatability and linearity of the method were validated by intra‐day and inter‐day precision. Then, the proposed method was applied to Zyrtec^® tablet, syrup, and oral drop. The results indicate that the method is simple, accurate, and precise for the analysis of cetirizine.