Nano-plasmonics and electronics co-integration in CMOS enabling a pill-sized multiplexed fluorescence microarray system
Realizing accurate point-of-care diagnostics is the key to an efficient detection and monitoring of diseases, as required to provide patients with personalized, adequate, and successful medical treatments. To this aim, miniaturized multiplexed biosensors revealing complex molecular fingerprints in nearly real-time are needed. Biosensors based on fluorescence detection are excellent candidates to meet such requirements. However, current devices present a limited compactness because they include bulky optical components. In their work, Lingyu Hong and coworkers present a miniaturized multiplexed biosensor enabling a 96-channel fluorescence readout on a 2-mm2 chip. Labeled target molecules attach to a glass slide at functionalized areas placed above the readout channels. Each of these channels consists of an array of integrated photodetectors covered with vertical plasmonic waveguide filters that transmit only the fluorescence signal coming from the labeled target molecules above them. This configuration enables a monolithic design without bulky optical components and is compatible with well-established CMOS fabrication processes. After suitable calibration and electronic signal processing, detection below the pM level is reported for the biosensor.