We have developed a rapid magnetic microparticle-based detection strategy for malarial biomarkers Plasmodium lactate dehydrogenase ( p LDH) and Plasmodium falciparum histidine-rich protein II ( Pf HRPII). In this assay, magnetic particles functionalized with antibodies specific for p LDH and Pf HRPII as well as detection antibodies with distinct enzymes for each biomarker are added to parasitized lysed blood samples. Sandwich complexes for p LDH and Pf HRPII form on the surface of the magnetic beads, which are washed and sequentially re-suspended in detection enzyme substrate for each antigen. The developed simultaneous capture and sequential detection (SCSD) assay detects both biomarkers in samples as low as 2.0 parasites/µl, an order of magnitude below commercially available ELISA kits, has a total incubation time of 35 min, and was found to be reproducible between users over time. This assay provides a simple and efficient alternative to traditional 96-well plate ELISAs, which take 5–8 h to complete and are limited to one analyte. Further, the modularity of the magnetic bead-based SCSD ELISA format could serve as a platform for application to other diseases for which multi-biomarker detection is advantageous. Graphical abstract Magnetic microparticle-based immunoassay reproducibly detects two malarial biomarkers in under an hour with detection limits an order of magnitude better than commercially available kits. fx1 Highlights • Rapid, magnetic microparticle-based detection of p LDH and Pf HRPII from one sample. • Detection of both biomarkers is critical in the context of malaria elimination. • Total incubation time of 35 min. • LODs an order of magnitude below commercial ELISA kits, within asymptomatic regime. • Reproducible across users over time, and simple enough for novice users.
【저자키워드】 malaria, immunoassay, Plasmodium lactate dehydrogenase, Plasmodium falciparum histidine-rich protein II,