title: Nanoparticle-Based Histidine-Rich Protein-2 Assay for the Detection of the Malaria Parasite Plasmodium falciparum.
abstract: A nanoparticle-based assay for detection and quantification of Plasmodium falciparum histidine-rich protein 2 (HRP2) in urine and serum is reported. The assay uses magnetic beads conjugated with anti-HRP2 antibody for protein capture and concentration, and antibody-conjugated quantum dots for optical detection. Western blot analysis demonstrated that magnetic beads allow the concentration of HRP2 protein in urine by 20-fold. The concentration effect was achieved because large volume of urine can be incubated with beads, and magnetic separation can be easily performed in minutes to isolate beads containing HRP2 protein. Magnetic beads and quantum dots conjugated to anti-HRP2 antibodies allows the detection of low concentrations of HRP2 protein (0.5 ng/mL), and quantification in the range of 33-2,000 ng/mL corresponding to the range associated with non-severe to severe malaria. This assay can be easily adapted to a noninvasive point-of-care test for classification of severe malaria.
authors.affiliation: Laboratorio de Investigación en Enfermedades Infecciosas, Universidad Peruana Cayetano Heredia, Lima, Peru.
authors.forename: Yagahira E
authors.initials: YE
authors.lastname: Castro-Sesquen
authors.affiliation: Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland. Institute for Nanobiotechnology Johns Hopkins University, Baltimore, Maryland.
authors.forename: Chloe
authors.initials: C
authors.lastname: Kim
authors.affiliation: Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland.
authors.forename: Robert H
authors.initials: RH
authors.lastname: Gilman
authors.affiliation: Department of Molecular Microbiology and Immunology, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland.
authors.forename: David J
authors.initials: DJ
authors.lastname: Sullivan
authors.affiliation: Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland. Institute for Nanobiotechnology Johns Hopkins University, Baltimore, Maryland. searson@jhu.edu.
authors.forename: Peter C
authors.initials: PC
authors.lastname: Searson
mesh_terms: D000913:Antibodies, Protozoan / Q000737:chemistry; D000953:Antigens, Protozoan / Q000652:urine*; D001681:Biological Assay; D015153:Blotting, Western; D002138:Calibration; D015870:Gene Expression; D006801:Humans; D059346:Magnets; D016778:Malaria, Falciparum / Q000175:diagnosis* / Q000469:parasitology / Q000652:urine; D053758:Nanoparticles / Q000737:chemistry*; D010963:Plasmodium falciparum / Q000235:genetics / Q000302:isolation & purification*; D015800:Protozoan Proteins / Q000652:urine*; D045663:Quantum Dots / Q000737:chemistry*; D012680:Sensitivity and Specificity
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; C514457:HRP-2 antigen, Plasmodium falciparum; D015800:Protozoan Proteins