Abstract
In the current study, a novel double-layer gold nanoparticles-electrochemical immunosensor electrode immobilized with tetrahydrocannabinol (THC) antibody derived from Balb/c mice was developed. To increase the fixed quantity of antibodies and electrochemical signals, an electrochemical biosensing signal amplification system was utilized with gold nanoparticles-thionine-chitosan absorbing horseradish peroxidase (HRP). In addition, a transmission electron microscope (TEM) was used to characterize the nanogold solution. To evaluate the quality of the immunosensor, the amperometric I-t curve method was applied to determine the THC in PBS. The results showed that the response current had a good linear correlation with the THC concentration range from 0.01~10³ ng/mL with a correlation coefficient of 0.9986. The lowest detection limit for THC was 3.3 pg/mL (S/N = 3). Moreover, it was validated with high sensitivity and reproducibility. Apparently, the immunosensor may be a very useful tool for monitoring the THC.