FIG. 7.

SiMoT sensing measurements. (a) Transfer curves with varied IgG concentrations of 6 zeptoMolar (zM, black curve), $(6\pm 3)\times 10$ zM (blue curve), $(6\pm 1)\times 102$ zM (dark curve), $(6.7\pm 0.1)\times 103$ zM (magenta curve), and $(6.67\pm 0.01)\times 106$ zM (light green curve) in PBS standard solutions. (b) Negative shifts in the work function with corresponding threshold voltage shifts at each functionalization step. EF is the gate electrochemical potential and VL is the vacuum level. Reproduced with permission from Macchia et al., Nat. Commun. 9, 3223 (2018). Copyright 2018, Author(s), licensed under Attribution 4.0 International (CC BY 4.0).