Mercaptophenylboronic Acid-Mediated Nanozyme Immunochromatographic Assay for Simultaneous Detection of Respiratory Bacteria and Virus

Rapid, sensitive, and accurate detection of respiratory pathogens is essential yet challenging. Here, this study presents a universal nanozyme immunochromatographic assay (ICA) that utilizes the broad binding capacity of 4-mercaptophenylboronic acid (MPBA) for glycosylated molecules on bacterial and viral surfaces, along with the colorimetric-catalytic dual enhancement capability of multi-tentacle magnetic nanozyme (FeAu@AuIr), to achieve ultrasensitive, wide-range, and simultaneous detection of multiple respiratory pathogens. The virus-like biomimetic FeAu@AuIr with multi-tentacle shell is prepared by sequentially assembling a layer of large Au nanoparticles and a layer of highly catalytic 5 nm AuIr nanoparticles on 160 nm Fe₃O₄ surface, greatly enhancing the universal capture/detection capability of detection system for both bacteria and virus. By simultaneously detecting two significant respiratory bacteria (Streptococcus pneumoniae and Pseudomonas aeruginosa) and one respiratory virus (Severe Acute Respiratory Syndrome Coronavirus 2), this study demonstrates that combination of FeAu@AuIr-MPBA probe and antibody-modified ICA strips can achieve ultrasensitive and highly specific detection of different respiratory pathogens, with sensitivity and detection range improved by more than 238 times compared to existing colorimetric ICA methods. Moreover, the practical utility of the FeAu@AuIr-based ICA is validated through testing 170 positive clinical respiratory samples, underscoring its considerable potential for real-time pathogen detection in both clinical and field settings.