1.Recent advances of capillary electrophoresis in pharmaceutical analysis
Leena Suntornsuk. Anal Bioanal Chem (2010) 398:29–52
Prutthiwanasan et al. developed an efficient and rapid CZE method, using indirect UV detection, for assay of three alkylphosphonate drugs (fosfomycin disodium (FOS), clodronate disodium (CLO), and alendronate sodium (ALN)) in pharmaceutical formulations. The multiple probe BGE containing 30 mmol L−1 benzoic acid, 5 mmol L−1 salicylic acid and 0.5 mmol L−1 cetyltrimethylammonium bromide (CTAB) (pH 3.8), the temperature (30 °C), the applied potential (−30 kV), and detection at 220 were optimized. Addition of CTAB to the two-probe BGE greatly improved peak symmetry and EOF reversal, and the negative voltage polarity led to the co-EOF flow and short analysis time. All analytes were well resolved (resolution (R)>2.2) in 3.2 min. Good linearity (r>0.999 in the ranges 20–1,000 μgmL−1 for FOS, 100–1,000 μgmL−1 for clodronate disodium (CLO), and 100–750 μgmL−1 for ALN), repeatability (relative standard deviation (RSD)<2.15%), recovery (99.3–101.1%) and sensitivity (limit of detection<50 μgmL−1)wereobtained by use of the proposed method. The method successfully applied to analysis of FOS, clodronate disodium (CLO), and ALN in dosage forms.