Synthesis and application of polymers nanoparticles with molecular imprints of salbutamol in the recognition layer of a piezoelectric sensor
In this paper were studied the conditions for the synthesis of polymers nanoparticles with molecular prints of salbutamol (the active component of drugs for the treatment of asthma and doping for athletes) by the method of mini-emulsion polymerization based on methacrylic acid and ethylene glycol dimethacrylate, as functional and cross-monomers. The effect of sodium dodecyl sulfate concentration, the nature of the radical polymerization initiator, and the presence of a hydrophobic agent in the system on the average diameter of the MIP particles and their dispersion was established. The resulting micelles solubilize the monomers and the template and inside them a polymerization process takes place with the formation of MIP particles. To limit the size of the droplets, the two-phase system was ultrasonically subjected. An increase in the surfactant concentration leads not only to an increase in the homogeneity of the obtained nanoparticles, but also to a decrease in their average diameter. A method for forming a recognition layer on the sensor electrode surface was described. The composition of the regenerating solution, which allows the maximum extraction of salbutamol from the polymer layer and maintain a constant number of prints for re-binding to the template was proposed. The characteristics of the recognition layer based on the MIP salbutamol nanoparticles were determined by the method of piezoquartz microweighting, which allowed us to estimate the surface concentration of molecular prints and the stability of the recognition layer and calculate the degree of imprinting. The analytical characteristics of the MIP-sensor for determining salbutamol in water solutions were established, the selectivity of the recognition layer was evaluated. The metrological characteristics of piezoelectric sensors based on MIP of salbuta-mol were established, the calibration dependence of the analytical signal on the concentration is linear in a fairly wide concentration range of 26-526 μg/cm<sup>3</sup>, the detection limit is 7.8 μg/cm<sup>3</sup>.