This sensitive detection was due to the integration of a porous nanomaterial with excellent electrochemical properties that can be easily modified for site-specific surface detection. Lee et al. developed a photothermal biosensor (PTB) was developed for detecting C-reactive protein (CRP) in human saliva. It can measure the concentration of CRP (0.1-100 ng/mL) in 7-μL sample volumes. The CRP is captured by a sandwich immunoassay on the sensor, and gold nanoparticles conjugated with antibodies cause a photothermal effect when irradiated with a laser.