Silver nanoparticle noduled ZnO nanowedge fetched novel FO-LMR based H₂O₂ biosensor: A twin regime sensor for in-vivo applications and H₂O₂ generation analysis from polyphenolic daily devouring beverages

Zinc oxide (ZnO) fetched lossy mode resonance based fiber optic biosensor for the detection of H₂O₂ is reported. The sensor works in two regimes of H₂O₂ concentration range, one for in-vivo applications covering the range which includes adequate, enduring and toxic levels in human body and the other for the range of H₂O₂ liberated by polyphenolic-daily consuming beverages. The sensor probe is fabricated in two steps. In the first step, ZnO film is coated over unclad core of the fiber followed by a layer of ZnO nanorods. In the second step, the morphological accession of ZnO nanowedge from its nanorod structure along with the silver nanoparticle growth as nodules on nanowedge surface is carried out in the presence of UV light. The performance of the probe is evaluated using samples of H₂O₂ of different concentrations prepared in laboratory. Its performance is also tested on real samples of daily in taking polyphenol rich beverages such as green tea, black tea and coffee in a pseudo-corporal condition. This is for the analysis of maximum H₂O₂ generation as intermediate and by-products by such consumables in human body. The sensor possesses best limit of detection, fair selectivity and reusability which supports real time applications.