Identification of Biomolecules and Food Analytes Using Dielectric Signature Based Junctionless Gate All Around MOSFET Biosensor for Higher Sensitivity

The authors have developed a novel device, the Split-Gate Junctionless Gate-All-Around (SGJL-GAA) MOSFET for biosensor applications, utilizing split-gate technology for the first time. This dielectric design has been formulated for this InGaAs-based SGJL-GAA MOSFET, featuring a nanogap cavity for label-free biosensing applications. The SGJL-GAA MOSFET can detect the presence of various neutral biomolecules, charged protein biomolecules, and neutral food analytes by leveraging its dielectric signature. Detection within the cavity area is achieved by monitoring changes in the dielectric constant associated with biomolecules such as streptavidin, APTES, biotin, proteins, and DNA, as well as food analytes like gluten, zein, keratin, and gelatin. The proposed biosensor design has been evaluated for its electrostatic, linearity, and RF properties, as well as the sensitivity of these parameters. While neutral streptavidin biomolecules exhibit greater sensitivity regarding changes in linearity, neutral DNA biomolecules show higher sensitivity to changes in electrostatic and RF performance. Furthermore, the parameters were analyzed in the presence of charged protein biomolecules (ranging from − 10 × 10¹¹ C to 10 × 10¹¹ C); sensitivity was found to increase with the magnitude of the charge. Additionally, gelatin-based food analytes demonstrated the highest sensitivity alongside superior electrostatic, linearity, and RF performance. The biosensing system operates effectively with 10 × 10¹¹ C charged proteins, gelatin-neutral food analytes, and DNA-neutral biomolecules.