Capillary electrophoresis to determine entrapment efficiency of a nanostructured lipid carrier loaded with piroxicam

Abstract

A simple and fast capillary electrophoresis method has been developed to determine the amount of piroxicam loaded in a drug delivery system based on nanostructured lipid carriers (NLC). The entrapment efficiency of the nanostructured lipid carrier was estimated by measuring the concentration of drug not entrapped in a suspension of NLC. The influence of different parameters on migration times, peak symmetry, efficiency and resolution was studied; these parameters included the pH of the electrophoretic buffer solution and the applied voltage. The piroxicam peak was obtained with a satisfactory resolution. The separation was carried out using a running buffer, which it is composed of 50 mmol L-1 ammonium acetate and 13.75 mmol L-1 ammonia at pH 9. The optimal voltage was 20kV and the cartridge temperature was 20°C. The corresponding calibration curve was linear over the range of 2.7 ? 5.4 µg mL-1 of NLC suspension. The reproducibility of migration time and peak area were investigated, and the obtained RSD% values (n = 5) were 0.99 and 2.13, respectively.