Methods gold standard in clinic millifluidics multiplexed extended gate field-effect transistor biosensor with gold nanoantennae as signal amplifiers

• DOI: 10.1016/j.bios.2023.115701
• Publication Date: 2023-09-22T00:12:23Z
• Authors: Željko Janićijević; Trang-Anh Nguyen-Le; Ahmed Alsadig; Isli Cela; Rugilė Žilėnaite; Taufhik Hossain T...; Manja Kubeil; Michael Bachmann; Larysa Baraban
• Keywords: Bioconjugation

We present a portable multiplexed biosensor platform based on the extended gate field-effect transistor and demonstrate its amplified response thanks to gold nanoparticle-based bioconjugates introduced as part of immunoassay. The comprises disposable chip hosting an array 32 electrodes, readout module single operating in constant charge mode, multiplexer scan sensing electrodes one-by-one. Although employing only off-the-shelf electronic components, our achieves sensitivities comparable fully customized nanofabricated potentiometric sensors. In particular, it reaches detection limit 0.2 fM for pure molecular assay when horseradish peroxidase-linked secondary antibody (∼0.4 nM reached by standard microplate methods). Furthermore, with nanoparticle bioconjugation format, we ca. 5-fold amplification compared assay, at 13.3 fM. Finally, elaborate mechanism this propose that nanoparticle-mediated disruption diffusion barrier layer is main contributor signal enhancement. These results show great potential portable, sensitive, cost-efficient multidimensional diagnostics clinical laboratory settings, including e.g., serological tests or pathogen screening.