Enhanced THz signal via Au encapsulated in hydrogel gel for non-enzymatic glucose sensing

Non-enzymatic glucose sensors were developed based on Au nanoparticles embedded in the hydrogel system. The sensors were soaked in glucose aqueous solutions with concentrations ranging from 0 to 1.5 mg/mL for 30 min. Terahertz time domain spectroscopy was then used to measure the absorption of the sensors. The Au nanoparticles can oxidize the glucose molecules to gluconic acid, resulting in a pH change of the samples. The sensitivity of the sensors to glucose levels are therefore enhanced compared to traditional terahertz spectroscopy measurements.