A smart electrochemical sensor based upon hydrophilic core-shell molecularly imprinted polymer for determination of L-tryptophan

The present research addresses an efficient, eco-friendly, and facile sol-gel approach for the synthesis of hy-drophilic core-shell L-tryptophan (Trp) imprinted polysilicate on polyvinylpyrrolidone coated gold nanoparticles (AuNPs@PVP@SiO2MIP). Various characterization techniques including ultraviolet-visible (UV-vis) absorption spectroscopy, Fourier transform infrared (FTIR) transmission spectroscopy, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), energy dispersive X-ray analysis (EDX), dynamic light scattering (DLS), water contact angle (WCA) measurement, and cyclic voltammetry (CV) were employed to clarify the structure of the nanocomposite. The AuNPs@PVP@SiO2MIP nanostructure was utilized to construct a smart electrochemical sensor for Trp using a graphite (Gr) electrode substrate. The performance of the proposed sensor was optimized and evaluated. The calibration plot of Trp, which was obtained using linear sweep vol-tammetry (LSV), was linear in two concentration ranges of 1 mu M to 50 mu M and 50 mu M to 350 mu M. Moreover, the limit of detection (LOD) and limit of quantification (LOQ) were 0.3 mu M and 1 mu M on the basis of 3sb/m and 10sb/ m criteria, respectively. The applicability of the sensor for the determination of Trp in a real sample was monitored through the analysis of unspiked and spiked biomedical sample.