Micromolar Metabolite Measurement in an Electronically Multiplexed Format

Integrating Microfluidics and Electronics in Point-of-Care Diagnostics: Current and Future Challenges

Point-of-Care (POC) diagnostics have gained increasing attention in recent years due to its numerous advantages over conventional diagnostic approaches. As proven during the recent COVID-19 pandemic, the rapidity and portability of POC testing improves the efficiency of healthcare services and reduces the burden on healthcare providers. There are hundreds of thousands of different applications for POC diagnostics, however, the ultimate requirement for the test is the same: sample-in and result-out. Many technologies have been implemented, such as microfluidics, semiconductors, and nanostructure, to achieve this end. The development of even more powerful POC systems was also enabled by merging multiple technologies into the same system. One successful example is the integration of microfluidics and electronics in POC diagnostics, which has simplified the sample handling process, reduced sample usage, and reduced the cost of the test. This review will analyze the current development of the POC diagnostic systems with the integration of microfluidics and electronics and discuss the future challenges and perspectives that researchers might have.

A Hybrid Microfluidic Electronic Sensing Platform for Life Science Applications

This paper presents a novel hybrid microfluidic electronic sensing platform, featuring an electronic sensor incorporated with a microfluidic structure for life science applications. This sensor with a large sensing area of 0.7 mm² is implemented through a foundry process called Open-Gate Junction FET (OG-JFET). The proposed OG-JFET sensor with a back gate enables the charge by directly introducing the biological and chemical samples on the top of the device. This paper puts forward the design and implementation of a PDMS microfluidic structure integrated with an OG-JFET chip to direct the samples toward the sensing site. At the same time, the sensor’s gain is controlled with a back gate electrical voltage. Herein, we demonstrate and discuss the functionality and applicability of the proposed sensing platform using a chemical solution with different pH values. Additionally, we introduce a mathematical model to describe the charge sensitivity of the OG-JFET sensor. Based on the results, the maximum value of transconductance gain of the sensor is ~1 mA/V at Vgs = 0, which is decreased to ~0.42 mA/V at Vgs = 1, all in Vds = 5. Furthermore, the variation of the back-gate voltage from 1.0 V to 0.0 V increases the sensitivity from ~40 mV/pH to ~55 mV/pH. As per the experimental and simulation results and discussions in this paper, the proposed hybrid microfluidic OG-JFET sensor is a reliable and high-precision measurement platform for various life science and industrial applications.