Photoelectrochemical bioanalysis: A mini review

Photoelectrochemical detection of metal ions

Depending on the situation, metal ions may either play beneficial roles or be harmful to human health and ecosystems. Sensitive and accurate detection of metal ions is thus a critical issue in the field of analytical sciences and great efforts have been devoted to the development of various metal ion sensors. Photoelectrochemical (PEC) detection is an emerging technique for the bio/chemical detection of metal ions, and features a fast response, low cost and high sensitivity. Using representative examples, this review will first introduce the fundamentals and summarize recent progress in the PEC detection of metal ions. In addition, interesting strategies for the design of particular PEC metal ion sensors are discussed. Challenges and opportunities in this field are also presented.

Photoamperometric flow injection analysis of glucose based on dehydrogenase modified quantum dots-carbon nanotube nanocomposite electrode

In this work, a core-shell quantum dot (QD, ZnS-CdS) was electrodeposited onto multiwalled carbon nanotube modified glassy carbon electrode (ZnS-CdS/MWCNT/GCE) and following glucose dehydrogenase (GDH) was immobilized onto QD modified electrode. The proposed electrode (GDH/ZnS-CdS/MWCNT/GCE) was effectively used for the photoelectrochemical biosensing of glucose in flow injection analysis (FIA) system using a home-made flow cell. Results from cyclic voltammetric and FI amperometric measurements have revealed that GDH/ZnS-CdS/MWCNT/GCE is capable of signaling photoelectrocatalytic activity toward NADH when the surface of enzyme modified electrode was irradiated with a light source (250W Halogen lamp). Thus, photoelectrochemical biosensing of glucose was monitored by recording current-time curve of enzymatically produced NADH at optimized conditions. The biosensor response was found linear over the range 0.010-2.0mM glucose with detection limits of 6.0 and 4.0μM for amperometric and photoamperometric methods, respectively. The relative standard deviations (n=5) for 0.5mM glucose were 5.8% and 3.8% for photoamperometric and amperometric results, respectively. The photoelectrochemical biosensor was successfully applied to the real samples. The results with this biosensor showed good selectivity, repeatability and sensitivity for monitoring glucose in amperometric and photoamperometric FIA studies.

Photoelectrochemical bioanalysis: the state of the art

This review provides a panoramic snapshot of the state of the art in the dynamically developing field of photoelectrochemical bioanalysis.

A simple label-free photoelectrochemical immunosensor for highly sensitive detection of aflatoxin B1based on CdS–Fe3O4magnetic nanocomposites

A simple label-free photoelectrochemical (PEC) platform was developed based on magnetic CdS–Fe₃O₄nanocomposites and used for detection of aflatoxin B₁(AFB₁).

A new visible-light-driven photoelectrochemical biosensor for probing DNA–protein interactions

A novel photoelectrochemical approach was achieved for the detection of a DNA binding protein via the protein–DNA interaction.

Bismuthoxyiodide nanoflakes/titania nanotubes arrayed p-n heterojunction and its application for photoelectrochemical bioanalysis

We have developed sensitive detection of cancer biomarker vascular endothelial growth factor (VEGF) using the p-n heterojunction comprised of p-type BiOI nanoflakes (NFs) array and n-type TiO₂ nanotubes (NTs) array. Due to the unique arrayed structure and the synergy effect of photoelectrochemistry in the formed p-n junction, the synthesized configuration has superior excitation efficiency and thus excellent photoresponsibility. Then, the fabricated p-n heterojunction was integrated with an exquisite bioassay protocol for addressing VEGF using a sandwich immunoassay with glucosedehydrogenase (GDH) as the enzyme tags. Due to the excellent performance of BiOI NFs array/TiO₂ NTs array and the ingenious signaling mechanism, the proposed system could achieve the sensitive and specific VEGF detection. This work not only presents a simple BiOI NFs array/TiO₂ NTs array p-n heterojunction for general applications in the broad photochemistry areas, but also opens a different horizon for current development of advanced PEC biomolecular detection.