Light-responsive bifunctional crosslinker enables facile preparation of antifouling sensor array for immunodetection of viral antigens

To achieve reliable detection of viral antigens, it is critical to develop of antifouling sensor arrays. Herein, we introduce a robust strategy for facile design and construction of hydrogel-based antifouling sensor arrays with a light-responsive bifunctional crosslinker. Upon UV light irradiation, the capture antibodies and blocking agents can be chemically conjugated onto the hydrogel interface to generate antifouling sensor arrays with desirable protein patterns with the aid of a hole-array mask. We demonstrated the antifouling sensor arrays for the quantitative detection of SARS-CoV-2 spike protein with satisfying sensitivity and high signal-to-background ratio. We further confirmed the prepared multiplexed sensor arrays for the detection of multiple viral proteins simultaneously in complex environments. Moreover, we achieved the quantitative detection of synthetic virus-like particles and SARS-CoV-2 pseudoviruses with satisfying detection performances. All these evidences suggested that the hydrogel-based antifouling sensor arrays holds great potential for quantitative analysis of viral antigens and virus particles in real applications.