Sustainable and optimized fabrication of microfluidic devices for electrochemical detection and monitoring of microbial biofilms

In healthcare and industry, infections caused by biofilms and unwanted buildup in the environment are big problems, making it important to have affordable and easy-to-use monitoring tools. The study aims to create an affordable and eco-friendly electrochemical microfluidic device that can easily check biofilm growth without needing invasive methods, making it simpler and cheaper than traditional biosensors. The fabrication of the microfluidic device involved a resource-efficient approach, utilizing 3-D printed molds made from acrylonitrile butadiene styrene material, followed by polydimethylsiloxane casting to form the channels. Screen-printed electrodes (SPEs) were integrated into the device, and acetone washing was used for channel formation. The device performed testing with one bacterial strain (Staphylococcus aureus), one fungal strain (Candida albicans), and two real samples (clinical blood and wastewater) employing impedance methods. Additionally, the study simulated real-world conditions by utilizing clinical and wastewater samples to monitor biofilm growth. Biofilm development in the microfluidic device exhibited a sigmoidal growth pattern, with impedance increases of ~ 74.4% for S. aureus, 73.78% for C. albicans, and 82.7% and 87.34% for clinical and wastewater samples, respectively. High-resolution SEM imaging confirmed the presence of biofilms on the surface of the SPEs. The dynamic range of the device was found to be 1291.57–1811.25 ohms, with a limit of detection of 0.208 CFU/mL and a sensitivity of 10.83 µA/CFU/mL. The device's sustainable fabrication process and reliable performance make it a practical option for researchers with limited resources, offering a valuable alternative to traditional biofilm study methods.

Graphical abstract