3D-architectured aptasensor for ultrasensitive electrochemical detection of norovirus based on phosphorene-gold nanocomposites

A 3D electrochemical aptasensor was constructed for sensitive detection of norovirus, featuring in a highly sensitive and movable spherical working electrode (WE) decorated with phosphorene-gold nanocomposites (BP-AuNCs) and screen-printed electrodes on fabric. The BP-AuNCs were prepared via the in situ reduction of phosphorene nanosheets (BPNSs) on chloroauric acid (HAuCl4), representing a simple, low-cost and mass-producible process. The design of the movable spherical WE facilitated the increase of surface area, ease of sampling and avoidance of cross-contamination. The critical design parameters of the 3D electrochemical aptasensor, including the concentration of immobilized aptamer and reaction time, were adjusted to yield tunable ranges for the assay dynamic range and limit of detection (LOD) for the recombinant norovirus-like particles. Under optimum conditions, the 3D electrochemical aptasensor revealed a limit of detection (LOD) of 0.28 ng/mL with a linear range between 1 ng/mL and 10 µg/mL. The relative standard deviation (RSD) of repeatability and reproducibility of the aptasensor were 2.29% and 3.03%, respectively. It was applied to determine norovirus spiked oyster samples and the recovery was found between 97.2% and 103.7%. In addition, it exhibited good stability, repeatability and selectivity. We believe that the proposed 3D electrochemical aptasensor provides a facile, low-cost paradigm for sensitive and selective detection of norovirus and would be of great potential in the realm of food safety and clinical diagnosis.