Trends of nucleic acid – based point-of-care diagnostics for infectious diseases

The global emergence and spread of infectious diseases highlights the importance of having an easily accessible, decentralized testing modality that is adept at quickly identifying the nucleic acids present in a Point-of-Care (PoC) setting. PoC-based nucleic acid diagnostics encompass a broad range of platforms, such as lateral flow, biochips, and biosensors, whose primary goal has always been to offer sensitive, selective, and economically viable testing beyond conventional laboratory facilities. The current review illustrates a comprehensive overview of PoC-based nucleic acid diagnostics for infectious diseases, as it is divided into three major operational steps: nucleic acid extraction, amplification, and detection. Firstly, it describes strategies that could effectively work as a PoC, such as magnetic bead-based, paper-based, and integrated microfluidic approaches, while further focusing on their ability to remain simplified, rugged, and equipment-free. Secondly, it summarizes key amplification methods, such as Polymerase Chain Reaction (PCR), Nucleic Acid Sequence-Based Amplification (NASBA), Recombinase Polymerase Amplification (RPA), and Loop-Mediated Isothermal Amplification (LAMP), as they have all been modified to effectively work under more rapid, low-power, and portable conditions. Lastly, it introduces all presently known detection platforms, starting from simpler colorimetric and fluorescent assays present in lateral flow or device platforms, to innovative and advanced biosensors like those exploiting CRISPR/Cas systems and toehold switch principles, as these detectively offer highly sensitive and highly programmable nucleic acid recognition.