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.