Zheyu Wang et al have developed a microneedle patch that can help to detect small amounts of antibodies in interstitial fluid. The noninvasive technology could provide an alternative to blood draws for antibody tests. The ultrasensitive and quantitative biodetection technology is based on a bilayered microneedle patch with plasmonic-enhanced fluoroimmunoassay. The researchers used plasmonic-fluors, fluorescent nanolabels, to boost the detection of protein biomarkers present in very low levels. The signal from the target biomarkers in samples was nearly 800 times more powerful compared with conventional fluorophores, and a magnetic backing layer to the patch implemented conventional immunoassay procedures, thus improving measurement consistency. Using a series of mouse models, the team demonstrated that the patch enabled simple and timely detection of biomarkers of interest, including longitudinal monitoring of inflammatory immune responses, evaluation of vaccine efficiency in a minimally invasive manner, as well as quantification of localized changes in protein content within the tissue microenvironment. The microneedle patch could facilitate point-of-care diagnostics and clinical longitudinal monitoring.
Source: Nature Biomedical Engineering volume 5, pages64–76(2021) https://www.nature.com/articles/s41551-020-00672-y