Title : Kinetics of silver ion encapsulation as nanoparticles using vaccinium oxycoccos plant extract for the efficient sensing of Cr(iii) ions and its biological assessment
Abstract:
This research reports a novel biosensor based on the ability of Vaccinium oxycoccos plant extract to reduce and encapsulate silver ions as nanoparticles. The sensor phenomenon for Cr3+ detection relies on the aggregation of dispersed silver nanoparticles upon the addition of Cr3+ ions. The interaction of polyphenolic plant extract with Cr3+ causes the formation of Cr–polyphenol–AgNPs complexes, which initiates the aggregation of nanoparticles in solution. This aggregation is evidenced by a gradual shift in the absorption band from 402 nm to 520 nm and changes in solution color from yellow to pink. With a correlation value (R2) of 0.997, the sensor’s detection limit is between 0.5 µM and 100 µM, demonstrating a strong linear response between the absorption ratio and Cr3+ concentration. The results are selective even in the presence of possible interfering ions like As3+, Co2+, Cd2+, Hg2+, Mn2+, Ni2+, Pb2+, Sn2+, and Cr6+ ions. The whole biosensor process is examined using spectroscopic and kinetic analysis. Spectroscopic analysis confirms the complexation process of Cr3+, while kinetic analysis reveals that the aggregation follows a pseudo-second-order reaction. Moreover, the results suggest that this biosensor has a very good antibacterial potential against Escherichia coli, significant antifungal activity against Syncephalastrum racemosum, and the various pathogens tested. Similarly, AgNPs and pure Vaccinium oxycoccos extracts were evaluated for their antioxidant effects, and the results indicated that AgNPs show more antioxidant potential as compare to pure Vaccinium oxycoccos extract. The results of sensing and biological assessments showed potential applications in pharmaceutical and environmental monitoring areas.
