Platinum Nanozyme-Catalyzed Gas Generation for Pressure-Based Bioassay Using Polyaniline Nanowires-Functionalized Graphene Oxide Framework

作者：Ruijin Zeng, Zhongbin Luo, Lijia Zhang, Dianping Tang · 发表于：Analytical Chemistry · 年份：2018 · DOI：10.1021/acs.analchem.8b03889 · 被引用次数：357 · 研究领域：Advanced biosensing and bioanalysis techniques、Advanced Nanomaterials in Catalysis、Electrochemical sensors and biosensors

Pressure-based bioassays incorporating biomolecular recognition with a catalyzed gas-generation reaction have been developed for gas biosensors, but most involve poor sensitivity and are unsuitable for routine use. Herein we design an innovative gas pressure-based biosensing platform for the detection of Kanamycin (Kana) on polyaniline nanowires-functionalized reduced graphene oxide (PANI/rGO) framework by using platinum nanozyme-catalyzed gas generation. The signal was amplified by coupling with catalytic hairpin assembly (CHA) and strand-displacement amplification (SDA). Upon target Kana introduction, the analyte initially triggered a SDA reaction between hairpin DNA1 and hairpin DNA2, and then induced CHA conjugation between magnetic bead-labeled hairpin DNA3 (MB-H3) and platinum nanoparticle-labeled hairpin DNA4 (Pt-H4) to form a three-dimensional network. Numerous platinum nanoparticles (peroxidase-like nanozymes) were carried over with magnetic beads to reduce hydrogen peroxide into oxygen. The as-produced gas compressed PANI/rGO frameworks (modified to polyurethane sponge, used as the piezoelectric materials) in a homemade pressure-tight device, thus causing the increasing current of PANI/rGO sponge thanks to its deformation. The change in the current caused by the as-generated gas pressure was determined on an electrochemical workstation. Under optimum conditions, PANI/rGO sponge exhibited outstanding compressibility, stable signal-waveform output, fast response and r...