Nucleic acid analysis on paper substrates (NAAPs): an innovative tool for Point of Care (POC) infectious disease diagnosis.

The cost-effective rapid diagnosis of infectious diseases is an essential and important factor for curing such diseases in the global public health care picture. Owing to poor infrastructure and lack of sanitation, these diseases have an extreme impact on remote and rural areas, especially in developing countries, and there are unresolved challenges. Molecular diagnosis, such as nucleic acid analysis, plays a key role in the significant treatment of numerous infectious diseases. Current molecular diagnostic assays require a sophisticated laboratory setup with expensive components. Molecular diagnosis on a microfluidic point-of-care (POC) platform is attractive to researchers for disease detection with proper prevention. Compared to various microfluidic substrate materials, paper-based POC technologies offer significant cost-effective solutions over high-cost clinical instruments to fill the gap between the needs of users and affordability. Low-cost paper-based microfluidic POC technologies provide portable and disposable diagnostic systems for multiple disease detection that may be extremely useful in remote areas. This article presents a critical review of paper-based microfluidic device technology which has become an imminent platform to adjust the current health scenario for the detection of diseases using different stages of nucleic acid analysis, such as extraction, amplification and detection of nucleic acid, with future perspectives for paper substrates.