The present research addresses an efficient, eco-friendly, and facile sol–gel approach for the synthesis of hydrophilic 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 voltammetry (LSV), was linear in two concentration ranges of 1 μM to 50 μM and 50 μM to 350 μM. Moreover, the limit of detection (LOD) and limit of quantification (LOQ) were 0.3 μM and 1 μM 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.

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