Determination of pentamidine in serum and urine by micellar electrokinetic chromatography

A number of parameters influencing the electrokinetic processing of pentamidine by micellar electrokinetic chromatography (MEKC) were studied in order to develop an analytical method for this compound. The parameters considered were: pH, ionic strength, and SDS concentration of electrolyte, temperature and working voltage. On the basis of the results obtained, the best analytical conditions for the detection of pentamidine in serum and urine by MEKC were determined. Analysis by MEKC permitted determination of the drug in 10 min. Good linearity, reproducibility and accuracy were obtained in the range 0-30 micrograms/ml for both samples, with a correlation coefficient r > or = 0.9998 and a recovery of 87-92% in serum and 90-108.9% in urine. We examined the metabolism of pentamidine using rat liver homogenates in order to exclude any possible interference of metabolites in the analysis of pentamidine.