Customized low-cost high-throughput amplifier for electro-fluidic detection of cell volume changes in point-of-care...

Current methods for measuring cell volume changes often rely on costly and non-portable equipment, limiting their use to controlled laboratory settings. While electro-fluidic techniques offer high-resolution and high-throughput capabilities, their reliance on commercial amplifiers increases costs and hinders field deployment. Prior research has shown that cell volume is a critical biomarker for disease and response to disinfectants. However, no prior work had resolved how to make such measurements portable and affordable. This gap motivated the development of a low-cost, portable amplifier to enable in-field electro-fluidic cell analysis. The need for real-time, high-throughput cell volume detection in clinical and environmental settings remains unmet. Existing techniques struggle with resolution and speed when applied to microbial cells. The challenge lies in balancing cost, portability, and performance. This paper addresses the limitations of current methods by proposing a novel hardware solution.

The goal of this research was to design and test a low-cost, portable amplifier for electro-fluidic cell volume detection. The study aimed to overcome the limitations of commercial amplifiers by developing a home-built alternative. The motivation stemmed from the need for in-field, high-throughput cell analysis in point-of-care applications. The research focused on bacterial volume changes in response to disinfectants, which are difficult to measure via traditional imaging. The authors sought to validate the amplifier's performance in terms of accuracy, noise, and throughput. They also aimed to demonstrate its compatibility with electro-fluidic devices for real-world use. The study's scope included characterization of the amplifier's key parameters and comparison with commercial models. The ultimate aim was to enable affordable, portable cell volume monitoring for clinical and environmental diagnostics.

The researchers designed a transimpedance amplifier using low-cost components and tested its performance in an electro-fluidic setup. They measured the amplifier's maximum range, absolute error, and RMS noise in the current signal. The bandwidth of the amplifier was also evaluated and compared to commercial alternatives. The device was integrated with a micropore-based system for cell volume detection. They used the amplifier to monitor bacterial cells passing through the micropore and recorded the resulting signals. The throughput was calculated based on the number of cells detected per second. The resolution was tested by measuring changes in cell diameter down to 1 micrometer. Finally, the system was used to assess E. coli cell volume changes after exposure to 5% ethanol.

The home-built amplifier achieved a throughput of approximately 1300 cells per second. It resolved cell diameter changes as small as 1 micrometer. The amplifier's maximum range was comparable to commercial models, with an absolute error percentage within acceptable limits. The RMS noise was measured and found to be suitable for high-resolution cell detection. The amplifier's bandwidth supported the required signal processing for real-time analysis. The device operated on battery power, making it suitable for point-of-care applications. The system successfully detected E. coli volume changes after exposure to 5% ethanol. The cost of the amplifier was about 100 times lower than commercial alternatives, while maintaining performance.

The study demonstrated that a low-cost, portable amplifier can effectively support electro-fluidic cell volume detection. The amplifier's performance in terms of throughput and resolution was comparable to commercial models. The device's portability and affordability make it suitable for in-field applications. The researchers confirmed that the amplifier can resolve cell diameter changes as small as 1 micrometer. The system was successfully used to measure E. coli volume changes after ethanol exposure. The cost reduction of approximately 100-fold supports widespread adoption in resource-limited settings. The authors propose that this amplifier can enhance the feasibility of point-of-care diagnostics. The results suggest that the electro-fluidic method, combined with the home-built amplifier, is a viable alternative to traditional techniques.