TiO2/WO3 nanoarrays photodetector and liposomes equipped with electron donor-mediated signal amplification for immunoassay applications

Abstract

Exploring efficient photoelectric conversion platforms and innovative sensing strategies is the driving force of sensors to realize sensitivity detection. In this work, a photoelectrochemical (PEC) sensor integrating the type-II heterojunction of TiO₂/WO₃ nanoarrays (NAs) composites and liposome-mediated electron donor equipping strategy, was present for highly sensitive immunoassays. TiO₂/WO₃ NAs with the well-ordered density orientation, stable signal output, and minimal variation between batches, were an excellent PEC sensing substrate for the analysis of low abundance disease-related markers. A complete chain of evidence confirmed the successful charge carriers transfer containing density functional theory (DFT), in situ XPS (ISI-XPS), and electron paramagnetic resonance (EPR). Impressively, liposome-encapsulated electron donor (ascorbic acid) was utilized as a signal amplification strategy, which effectively shortened the distance between the electron donor and the substrate material, improved the photoelectronic conductivity of the photoelectric sensing interface. Tumor Necrosis Factor-Like Ligand 1A (TL1A) as a new target for inflammatory bowel disease to test the feasibility of this "signal-on" immunosensor in the linear range from 10.00 pg/mL to 100.00 ng/mL. The sensing model is only a small demonstration of its application potential, and we also expect that this will be a promising path to broaden the analysis of other targets.