Ultrasound-radiated synthesis of PAMAM-Au nanocomposites and its application on glucose biosensor

Hybrid nanocomposites of carboxyl-terminated generation 4 (G 4) poly(amidoamine) dendrimers (PAMAM) with gold nanoparticles (AuNPs) encapsulated inside them were synthesized under ultrasound irradiation. The obtained nanocomposites were used to fabricate highly sensitive amperometric glucose biosensor which exhibited a high and reproducible sensitivity of 2.9 mA/mM/cm², response time less than 5 s, linear dynamic range from 0.1 to 15.8 μM, correlation coefficient of R² = 0.9988, and limit of detection (LOD), based on S/N ratio (S/N = 3) of 0.05 μM. A value of 2.7 mM for the apparent Michaelis-Menten constant K_M^app was obtained. The high sensitivity, wider linear range, good reproducibility and stability make this biosensor a promising candidate for portable amperometric glucose biosensor.