Determination of carbamazepine in formulation samples using dispersive liquid-liquid microextraction method followed by ion mobility spectrometry

A simple, sensitive, fast and efficient method based on dispersive liquid-liquid microextraction (DLLME) followed by ion mobility spectrometry (IMS) has been proposed for preconcentration and trace detection of carbamazepine (CBZ) in formulation samples. In this method, 1 mL of methanol (disperser solvent) containing 80 mu L of chloroform (extraction solvent) was rapidly injected by a syringe into a sample. After 5 min centrifugation, the preconcentrated carbamazepine in the organic phase was determined by IMS. Development of DLLME procedure includes optimization of parameters influencing the extraction efficiencies such as kind and volume of extraction solvent, disperser solvent and salt addition, centrifugation time and pH of the sample solution. The proposed method presented good linearity in the range of 0.05-10 mu g mL(-1) and the detection limit was 0.025 mu g mL(-1). The repeatability of the method expressed as relative standard deviation was 6 % (n = 5). This method has been applied to the analysis of carbamazepine formulation samples with satisfactory relative recoveries <= 75 %.