3D NiO nanoflakes/carbon fiber meshwork: Facile preparation and utilization as general platform for photocathodic bioanalysis

Herein, we describe a customized approach for facile preparation of three-dimensional (3D) NiO nanoflakes (NFs)/carbon fiber meshwork (CFM) and its validation as a common photocathode matrix for photoelectrochemical (PEC) bioanalysis, which to our knowledge has not been reported. Specifically, 3D NiO NEs/CFM was fabricated by a sequential liquid phase deposition and annealing process, which was then characterized by scanning electron microscopy, X-ray photoelectron spectrum, UV-vis absorption spectra and N-2 adsorption-desorption measurement. Sensitized by BiOl and incorporated with an alkaline phosphatase (ALP)/tyrosinase (TYR) bi-enzyme cascade system, a sensitive split-type cathodic PEC bioanalysis for the determination of ALP was achieved. This method can detect ALP concentrations down to 3 x 10(-5) U L-1 with a linear response range of 0.001-10 U L-1. Moreover, this proposed system exhibited good selectivity, stability and excellent performance for real sample analysis. This research features the facile preparation of 3D NiO NEs/CFM that could acts as a universal matrix for photocathodic analysis, and is envisioned to stimulate more effort for advanced 3D photocathode for PEC bioanalysis and beyond. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

This study describes a facile method for preparing 3D NiO nanoflakes/carbon fiber meshwork as a common photocathode matrix for photoelectrochemical bioanalysis. The method enables sensitive analysis of alkaline phosphatase with good selectivity, stability, and real sample analysis performance. The research highlights the potential of 3D photocathodes for advanced PEC bioanalysis and beyond.