Detection, quantification and degradation kinetic for five benzodiazepines using VAUS-ME-SFO/LC-MS/MS method for...

Benzodiazepines can make victims more docile, they are frequently used in drug-facilitated crimes, such as robberies and sexual assaults. Therefore, it is essential to develop techniques for determining whether these chemicals are present in relation with illegal activity is crucial. Therefore, to determine the presence of five benzodiazepines (alprazolam, clonazepam, diazepam, lorazepam, and oxazepam) in water, alcoholic beverages, and non-alcoholic beverages, a simple and direct, miniaturized, and effective vortex assisted ultrasound based microextraction using solidification of floating organic droplets (VAUS-ME-SFO) in combination with LC-MS/MS was developed. 1-Undecanol and acetonitrile, respectively, served as the extractant and disperser solvents. Many other parameters affect the efficiency of the developed analytical procedure VAUS-ME-SFO/LC-MS/MS. These parameters were optimized using Plackett Burman Design and Central Composite Design to obtain reliable results. The optimum conditions for the extraction were: 10.0 mL of sample; 180 μL acetonitrile, as a dispersive solvent; 200 μL of 1-undecanol, as an extraction solvent; pH 7; 105 s of vortex agitation; 120 s of ultrasonication application and 3 min of centrifugation at 7000 rpm. The benzodiazepines were separated by a chromatographic separation technique carried out by a UPLC system consisting of a binary mobile phase. The solvent system comprises of 0.1% Formic acid in Milli-Q (Solvent A) and 0.1% Formic acid in ACN (Solvent B) with a gradient flow of 3.5 min total analysis time. Under the optimized conditions, the calibration curve was studied in the range of 0.124-7.810 ng mL^-1. The regression correlation coefficient (R²) value of all targeted analytes ranges from 0.993 to 0.999. The LOD and LOQ of VAUS-ME-SFO methods using LC-MS/MS analysis range from 0.316 to 0.968 ng mL^-1 and 1.055-3.277 ng mL^-1 respectively. The repeatability within a day varied from 0.6 to 3.5%, and the reproducibility across days varied from 2.2 to 6.3%. The recoveries ranges for water, alcoholic and non-alcoholic beverages from 70.77 to 114.53%, 63.20-102.21% and 66.23-113.28% respectively. Further, the degradation kinetics was studied to establish the half-life of each targeted analyte in the matrix undertaken in the study. The water samples were classified based on their BDZs residues. This implies that the more health care and anthropogenic activity, the more the BDZs residue will be in water samples.