Fig. 3.

Protein detection using thermally reduced graphene oxide (TRGO) sheets decorated with gold nanoparticle–antibody conjugates. (a) Schematic of a TRGO FET. Anti-IgG is anchored to the TRGO sheet surface through AuNPs and functions as a specific recognition group for the IgG binding. The electrical detection of protein binding is accomplished by FET and direct current measurements. (b) Sensor sensitivity (relative resistance change, %) versus the IgG concentration. The dashed line represents the noise level from the buffer solution. (c) Comparison of the sensor sensitivity in response to complementary IgG, mismatched IgM, mismatched HRP, and PBS buffer. Reproduced from ref. ⁶⁶ with permission from Wiley.