This work reports a 3D-printed virus sensing device that combines the functions of sample enrichment and quantification. The device consists of a nanoplasmonic biosensor surrounded by a biomimetic superhydrophobic structure. The superhydrophobic structure serves as a sample concentrator that can enrich the target analyte, which is subsequentially quantified by the nanoplasmonic biosensor. Both nanoscale sensor and microscale hydrophobic sample concentrator were fabricated using a high-resolution 3D printer through two-photon polymerization lithography (TPL). The design of the 3D-printed superhydrophobic microstructure was inspired by natural patterns found on surfaces like lotus leaves, which are known for their water-repellent properties. The TPP-based 3D printing approach enables the integration of two functions into one chip with a low-cost, high resolution, and simple fabrication process. This system was used to detect the swine influenza A virus contained in sample droplet with a starting volume of 25 μL. During a test, the droplet volume reduced due to evaporation, which was facilitated by the plasmonic heating. As a results the droplet’s diameter can shrink from 3.5 mm to 0.1 mm within 15 minutes. The volume reduction corresponds to the virus concentration increase over 4 × 104 times. The implementation of superhydrophobic sample concentration around of the sensor significantly improved the immobilization of target viruses on the plasmonic sensor. The device not only achieved a higher sensitivity but also reduced the assay time.
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