Strategies for Engineering Affordable Technologies for Point-of-Care Diagnostics of Infectious Diseases.

Disease prevalence is highest in low-resource settings (LRS) due to the lack of funds, infrastructure, and personnel required to carry out laboratory-based molecular tests. In high-resource settings, gold-standard molecular tests for diseases consist of nucleic acid amplification tests (NAATs) due to their excellent sensitivity and specificity. These tests require the extraction, amplification, and detection of nucleic acids from clinical samples. In high-resource settings, all three of these steps require highly specialized, costly, and onerous equipment that cannot be used in LRS. Nucleic acid extraction involves multiple centrifugation steps. Amplification consists of the polymerase chain reaction (PCR), which requires thermal cyclers. The detection of amplified DNA is typically done with specialized thermal cyclers that are capable of fluorescence detection. Traditional methods used to extract, amplify, and detect nucleic acids cannot be used outside of a laboratory in LRS. Thus, there is a need for affordable point-of-care devices to ease the high burden of disease in LRS.The past decade of work on paper-based fluidic devices has resulted in the invention of many paper-based biosensors for disease detection as well as isothermal amplification techniques that replace PCR. However, a challenge still remains in detecting pathogenic biomarkers from complex human samples without specialized laboratory equipment. Our research has focused on the development of affordable technologies to extract and detect nucleic acids in clinical samples with minimal equipment. Here we describe methods for the paper-based extraction, amplification, and detection of nucleic acids. This Account provides an overview of our latest technologies developed to detect an array of diseases in low-resource settings. We focus on detecting nucleic acids of H1N1,