| dc.description.abstract | At the onset of some infectious diseases, diagnostic biomarkers begin to circulate the bloodstream in low concentrations. Early detection of these biomarkers can improve treatment outcomes, prevent long-term complications, reduce transmissions, or screen for asymptomatic individuals. For malaria, eradication efforts have been confounded by an asymptomatic population, which cannot be diagnosed with current detection technologies such as light microscopy and lateral flow assays. We have developed a cyclic catch-and-release amplification design to detect malaria biomarker histidine rich protein II (HRPII) based on our previous work on extraction tubes and malaria catch-and-release. In this design, HRPII surface functionalized magnetic beads cyclically transfer NiNTA surface functionalized reporter beads from a “catch” chamber to an imidazole-rich “release-detect” chamber. In theory, the signal in the release-detect chamber should be amplified by N times x, where N is the number of cycles performed and x is the number of captured HRPII. We first created a self-contained prototype using polyhistidine functionalized magnetic beads, and demonstrated cyclic, linear amplification of NiNTA beads in the release-detect reservoir. Experimental parameters of the test were then optimized in a 96 well plate with anti-HRPII antibody functionalized magnetic beads and recombinant HRPII. The self-contained prototype was modified to incorporate the optimized parameters and antibody functionalized beads. The final design achieved a limit of detection of 5 nM HRPII with a signal to noise ratio of 20. Overall, this study supports cyclic catch-and-release amplification as a feasible alternative for malaria detection. | |
