Coacervative Microextraction With Solidification Of Floating Surfactant Droplets For The Determination Of Glibenclamide In Environmental Water Samples

A green coacervative microextraction method with solidification of floating surfactant droplets (CAME-SFD) has been developed for the preconcentration and determination of glibenclamide in environmental water samples followed by fluorescence detection. The microextraction was performed by mixing the sample with SDS in a strong acidic medium. Then, the resulting solution was heated in a water bath at 100 degrees C for 23 min. After this, the tube was placed in an ice bath, and the surfactant rich phase was removed and dissolved with 500 mu L of ethanol to perform the fluorometric measurements. A Plackett-Burman design was built to evaluate the main factors affecting the extraction, and the optimum values for the different factors were as follows: 5.0 mL of HCl 36.5-38.0% w/w (1.2 mol L-1), 800 mu L of a 0.8 mol L-1 SDS solution, 500 mg of NaCl and 800 mu L of MeOH.Under optimal conditions, the preconcentration factor was 86. The method presented a suitable liner range (0.50-4.20 mu g L-1), a low limit of detection (0.37 mu g L-1), and low RSD values (1.0-3.4%).The method was successfully applied to analyze surface water samples from the city of Bahia Blanca and Carmen de Patagones (Argentina), obtaining satisfactory recovery values (92.6-103.1%).