Towards point-of-care detection of microRNAs using paper-based microfluidics

Human immunodeficiency virus (HIV) weakens a person’s immune system by destroying cells which are important to fighting the disease and infection. HIV is a major global public health issue with an estimated 38 million people living with HIV at the end of 2019. There is no cure for HIV. However, increased access to effective prevention, diagnosis and treatment has enabled people living with HIV to lead healthy lives. Rapid diagnosis forms an important part of the WHO’s strategy for ensuring those who are HIV positive have immediate access to care. Perhaps more critical however is that effective diagnostic testing informs individuals of their HIV status, reducing the risk of transmission. HIV prevalence within the US is disproportionately high amongst Black/African American and Hispanic/Latino American populations who often have limited access to advanced medical clinics. In this paper, we present a lateral flow device designed to detect miR-150-5p; an emerging biomarker of HIV. Based on our preliminary results shown here, we are capable of detecting the miRNA sequence at sub-ng uL-1 using colorimetric analysis, without prior amplification of the target material. We have also detailed our initial results obtained from surface-enhanced Raman scattering measurements made at the device capture line, whilst the standard deviations are large, the technique shows lots of promise for lowering the detection limit in the future.