چكيده به لاتين
In this study, novel optical sensors were prepared using molecularly imprinted polymers (MIPs), cadmium selenide sulfide/zinc sulfide quantum dots (CdSeS /ZnS QDs) and glass slides. In the first part of the study, after covalent attachment of QDs to the surface of the amino-functionalized glass slide, a molecularly imprinted polymer layer, using lidocaine as the template, was embedded onto the modified surface of the glass slide@QDs. The prepared MIP-optosensor was characterized by various techniques such as scanning electron microscopy, elemental analysis and fluorescence spectroscopy and was used to sulfasalazine determination by spectrofluorimetric method (based on fluorescence quenching of QDs). Under optimal conditions (pH 4.5, the response time of 10 min), a linear response was obtained in the concentration range of 0.5-1.2 μm, with a correlation coefficient of 0.9986 and a detection limit of 0.0071 μm for sulfasalazine. Finally, the sensor was successfully applied to detection of sulfasalazine in biological samples (urine and plasma) with satisfactory recoveries in the range of 107-109%, and RSDs between 2.4-4.9%. The results showed that this sensor has advantages such as fast response, high sensitivity and selectivity and no need for organic solvents to detect sulfasalazine. In the second part of the study, another sensor, similar to that one synthesized in the first work, was prepared using a silica imprinted polymer modified QDs for lidocaine (as the template) and was characterized by various techniques. After optimizing the effective parameters on the sensor response, the linear range of 0.01-0.22 μm (coefficient of determination 0.9991) and the detection limit of 0.0063 μm were obtained for lidocaine. The prepared sensor was successfully used to detect trace amount of lidocaine in human plasma and urine with recoveries in the range of 96.4-47.5% (RSDs: 1.8-4.9%). The results showed that the proposed MIP-optosensor offered advantages such as simplicity, rapid response, good optical sensitivity and high selectivity toward lidocaine.
