Silver nanoparticles embedded polymer-zirconium-based metal–organic framework (polyUiO-66) for electrochemical biosensors of respiratory viruses

Sensitive and selective diagnosis of respiratory viruses is important because they can rapidly infect populations and seriously threaten the safety of human life. Here, novel electrochemical biosensors were developed based on the silver nanoparticles (AgNPs) embedded polymer-zirconium-based metal–organic framework (polyUiO-66@AgNPs) towards effective detection of respiratory viruses, including influenza A (H1N1) virus and the N-gene of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). The polyUiO-66@AgNPs hybrid was prepared using polyether polymer ligand with 1,4-benzenedicarboxylic acid unit as the linkers and AgNPs as the dopants by hydrothermal method. A large number of H1N1-targeted antibody and N-gene-targeted aptamer can be separately adsorbed on the developed matrix by integrating the enhanced electrochemical activity and biocompatibility of AgNPs with the high specific surface area, large pore size, and rich functionality of polyUiO-66. Consequently, the electrochemical biosensors based on polyUiO-66@AgNPs show amplified electrochemical responses for detecting H1N1 virus and SARS-CoV2 N-gene, with extremely low limits of detection (54.7 and 23.4 fg mL−1, respectively), as well as other superior sensing performances (e.g. high selectivity, good stability, excellent reproducibility, and acceptable regenerability). Moreover, the constructed biosensors show outstanding practicality. This work provides a new strategy for sensitive and selective detection of respiratory diseases and extends the applications of polyMOFs in biosensing fields.