Electrochemical sensor based on Carbon Ceramic Electrode modified by molecularly imprinted polymer nanoparticles for determination of Alprazolam drug

The determination of benzodiazepines in biological fluids has been a field of interest for many researchers. Alprazolam (ALP){8-chloro-1-methyl-6-phenyl-4H-s-triazol-o(4,3-a)(1,4) benzodiazepine } belongs to the class of benzodiazepine with anxiolytic, muscle relaxant, anticonvulsant properties which is generally used as a hypnotic and as a tranquilizer. In this research, a selective and sensitive voltammetric sensor based on carbon ceramic electrode modified by molecularly imprinted polymer (MIP) nanoparticles for determination of alprazolam drug is developed. The MIP nanoparticles were synthesized by suspension polymerization method and characterized by scanning electron microscopy (SEM). The non-imprinted polymer (NIP) nanoparticles were synthesized in a similar manner but in absence of alprazolam molecules. Then, the MIP nanoparticles were used as the recognition elements in construction of the sensor. The determination of alprazolam after its extraction onto the electrode surface was carried out by square wave voltammetry (SWV) method. The results show that the nano-MIP modified carbon ceramic electrode (MIP-CCE) had much higher adsorption ability to alprazolam than the nonimprinted polymer carbon ceramic electrode (NIP-CCE). The effect of some parameters on the sensor response, such as electrode composition, extraction and analysis conditions and electrochemical measurements conditions were studied. For optimization of parameters, Design Expert 7.0.0 software was used. Under optimized extraction and analysis conditions, Peak current showed a linear relationship with Alprazolam concentration, in the range of 7.0 × 10-9 to 5.0 × 10-7 M (R2=0.998) with a detection 226 limit of 5.01 × 10-9 M. The repeatability of the developed sensor in terms of relative standard deviation was 3.83%. The developed sensor was successfully applied for determination of alprazolam in pharmaceutical formulation and human serum samples.