Application of capillary electrophoresis for determination of glycosaminoglycans in biological and cosmetic samples

Abstract

In this research, on-line preconcentration and determination of glycosaminoglycans (GAGs), especially chondroitin sulfate (CS), dermatan sulfate (DS) and hyaluronic acid (HA) using capillary electrophoresis (CE) was developed. Large-volume sample stacking using an electroosmotic flow (EOF) pump (LVSEP) technique was employed for on-line preconcentration and improvement of the detection sensitivity in CE method. Central composite design (CCD) was used to simultaneously optimize all parameters for CE separation. The optimized CE conditions were background electrolyte consisting of 200 mM sodium dihydrogen phosphate, 200 mM buthylamine and 0.5% w/v polyethylene glycol at pH 4.0 and separation voltage of -16 kV. Limit of detections (LODs) and the limit of quantitations (LOQs) were 3.0, 5.0 and 1.0 and 10.0, 15.0 and 3.0 mg L-1 for CS, DS and HA, respectively. Precisions of the method were investigated from the percent relative standard deviation (%RSD) of corrected peak area of spiked standards in real samples, which were lower than 7% and 8% for intra-day and inter-day precisions, respectively. In addition, recovery percentages of CS and HA in various samples were found in the range of 84-104% and 73-120%., respectively. The developed method was reliable, simple and minimal sample pretreatment. Therefore, the proposed CE method could be applied to determine the amounts of CS and HA in biological samples (cerebrospinal fluid, cell culture media, plasma, urine) for prognostic diseases and medical pretreatment and in cosmetic and supplement samples for product quality control in the future.