Development of Novel Peptide-Modified Silver Nanoparticle-Based Rapid Biosensors for Detecting Aminoglycoside Antibiotics

Abstract

The detection and monitoring of aminoglycosideantibiotics (AGAs)have become of utmost importance due to their widespread use in humanand animal therapy, as well as the associated risks of exposure, toxicity,and the emergence of antimicrobial resistance. In this study, we successfullysynthesized casein hydrolysate peptides-functionalized silver nanoparticles(CHPs@AgNPs) and employed them as a novel colorimetric analyticalplatform to demonstrate remarkable specificity and sensitivity towardAGAs. The colorimetric and spectral response of the CHPs@AgNPs wasobserved at 405 and 520 nm, showing a linear correlation with theconcentration of streptomycin, a representative AGA. The color changesfrom yellow to orange provided a visual indication of the analyteconcentration, enabling quantitative determination for real-worldsamples. The AgNP assay exhibited excellent sensitivity with dynamicranges of approximately 200-650 and 100-700 nM for streptomycin-spikedtap water and dairy whey with limits of detection found to be & SIM;98and 56 nM, respectively. The mechanism behind the selective aggregationof CHPs@AgNPs in the presence of AGAs involves the amine groups ofthe target analytes acting as molecular bridges for electrostaticcoupling with hydroxyl or carboxyl functionalities of adjacent NPs,driving the formation of stable NP aggregates. The developed assayoffers several advantages, making it suitable for various practicalapplications. It is characterized by its simplicity, rapidity, specificity,sensitivity, and cost-effectiveness. These unique features make themethod a promising tool for monitoring water quality, ensuring foodsafety, and dealing with emergent issues of antibiotic resistance.