Project Summary HIV (human immunodeficiency virus) causes the acquired immune deficiency syndrome (AIDS). HIV/AIDS is one of the most serious public health challenges in the world. Early diagnosis of HIV can improve health outcome and reduce HIV transmission effectively. Currently nucleic acid amplification tests (NAAT) and enzyme-linked immunosorbent assays (ELISA) are the common methods for HIV detection. However, they can be only performed by professionals in a central laboratory. There is an essential need for development of point- of-care (POC) tools for early HIV detection. The p24 antigen is a protein biomarker that can be used for early detection. However, current POC testing tools have a poor limit of detection (LOD) toward p24 detection, which cannot be used for testing HIV within less than two weeks of post-infection The objective of this project is to develop a paper-based lateral flow strip (PLFS) for rapid, in-field detection of the p24 antigen in finger-prick whole blood samples. A plasmon-enhanced fluorescent sensor will be developed by utilizing a hierarchical three-dimensional nano-architecture. The chip-based fluorescent sensor and a plasma-separation unit will be integrated into a single paper-based microfluidic strip to enable blood sample pretreatment, fluid transport and analyte detection. The performance of the integrated PLFS will be tested in terms of limit of detection, sensitivity, selectivity and applicability to clinical patient samples. This need-driven work capitalizes on the expertise and skills of a multidisciplinary project team in device development, statistical modeling, medicine, HIV biology and clinical diagnosis. The discovery-driven research is novel because of the several appealing features. That is, incorporation of a blood plasma separation unit into the PLFS will eliminate the need of sample pretreatment in a central laboratory. The three-dimensional plasmonic nanostructure will enhance the sensitivity of the near-infrared fluorescence sensor. The PLFS can be read out by a commercial, battery-powered, hand-held fluorescence reader. The portable device can be employed as a POC tool for measuring p24 antigen in finger-prick (or heel-prick) blood samples in a minimally invasive way at home, in a clinic or other resource-limited settings. It can be used for self-testing by an untrained lay-person, and for early infant diagnosis. The data obtained from this portable device will assist early diagnosis of HIV within first two weeks of post-infection. Early detection of HIV infection will improve medical intervention outcome, and reduce HIV transmission, leading to substantial reduction in HIV/AIDS- related mortality and morbidity as well as economic costs.

Project Narrative This application aims to develop a portable device for early detection of HIV (human immunodeficiency virus) with finger-prick (or heel-prick) blood samples in a minimally-invasive way. This portable device will allow for rapid, accurate, sensitive, on-site, self-testing by untrained individuals to detect HIV within less than two weeks of post-infection in a resource-limited setting.