Monolithic integrated MQW-based optoelectronic glucose sensor

This study presents the development process of a multiquantum well (MQW)-based optoelectronic integrated device designed for precise glucose concentration measurements. The proposed monolithic device consists of two identical diodes containing InGaN/GaN MQWs, serving as a light emitter (LED) and a photodetector (PD), respectively. The chip is meticulously packaged with polydimethylsiloxane (PDMS) to facilitate exposure to the glucose solution. By monitoring changes in the photocurrent of the PD that detects scattered light of the LED propagating through the sapphire substrate, the chip can accurately reflect alterations in the glucose solution's concentration. The device's uniqueness lies in its ability to achieve this precision without the need for external optical components. The device exhibits a fast response, operating at a sub-second level, and can gauge glucose solutions with concentrations ranging from 5% to 40%. The fabricated optical sensing device showcases appealing characteristics, including compactness, stability, repeatability, and rapid response, making it highly suitable for glucose concentration measurement applications.