Magnetic Bead Characterization, Implementation and Control for the Extraction of Nucleic Acids from Patient Biofluid Samples in Point of Need Microfluidic Devices

The application of microfluidics in Point of Care (PoC) testing was a breakthrough in PoC diagnostics, yet high precision testing remains a challenge. In order to extract and isolate pure RNA or DNA from biofluids containing a virus or virion, small spherical magnetic particles called magnetic beads are commonly used in laboratories. Magnetic beads have many applications ranging from purification of nucleic acids, magnetic cell separation, targeted drug delivery to brain or malignant tumors, magnetic chaining etc. Unfortunately, integrating magnetic beads into PoC devices is challenging. This paper delves into a comparative study of the behaviour and parameters of five different sizes of carboxyl coated paramagnetic beads along with silica coated dynabeads. Their behavior is characterized in a microcapillary channel for a SARS-CoV-2 virus PoC testing kit to enrich the sample, concentrating the nucleic acid. This step would increase the sensitivity and specificity for any nucleic acid-based PoC testing device.