title: Development of a bead-based aptamer/antibody detection system for C-reactive protein.
abstract: A multiplexing bead-based platform provides an approach for the development of assays targeting specific analytes for biomonitoring and biosensing applications. Multi-Analyte Profiling (xMAP) assays typically employ a sandwich-type format using antibodies for the capture and detection of analytes of interest, and the system permits the simultaneous quantitation of multiple targets. In this study, an aptamer/antibody assay for the detection of C-reactive protein (CRP) was developed. CRP is an acute phase marker of inflammation whose elevated basal levels are correlated with an increased risk for a number of pathologies. For this assay, an RNA aptamer that binds CRP was conjugated to beads to act as the capture agent. Biotinylated anti-CRP antibody coupled to fluorescently labeled streptavidin was used for quantification of CRP. The detection limit of the CRP assay was 0.4 mg/L in diluted serum. The assay was then used to detect spiked CRP samples in the range of 0.4 to 10mg/L in diluted serum with acceptable recoveries (extrapolated values of 70-130%), including that of a certified reference material (129% recovery). The successful incorporation of the CRP aptamer into this platform demonstrates that the exploration of other aptamer-target systems could increase the number of analytes measurable using xMAP-type assays.
authors.affiliation: Environmental Health Science and Research Bureau, Health Canada, Tunney's Pasture, Ottawa, Ontario K1A 0K9, Canada.
authors.forename: Elyse D
authors.initials: ED
authors.lastname: Bernard
authors.affiliation: Environmental Health Science and Research Bureau, Health Canada, Tunney's Pasture, Ottawa, Ontario K1A 0K9, Canada.
authors.forename: Kathy C
authors.initials: KC
authors.lastname: Nguyen
authors.affiliation: Department of Chemistry, Carleton University, Ottawa, Ontario K1S 5B6, Canada.
authors.forename: Maria C
authors.initials: MC
authors.lastname: DeRosa
authors.affiliation: Environmental Health Science and Research Bureau, Health Canada, Tunney's Pasture, Ottawa, Ontario K1A 0K9, Canada.
authors.forename: Azam F
authors.initials: AF
authors.lastname: Tayabali
authors.affiliation: Environmental Health Science and Research Bureau, Health Canada, Tunney's Pasture, Ottawa, Ontario K1A 0K9, Canada. Electronic address: rocio.aranda-rodriguez@hc-sc.gc.ca.
authors.forename: Rocio
authors.initials: R
authors.lastname: Aranda-Rodriguez
mesh_terms: D000906:Antibodies / Q000737:chemistry*; D052157:Aptamers, Nucleotide / Q000737:chemistry*; D002097:C-Reactive Protein / Q000032:analysis* / Q000378:metabolism*; D006801:Humans; D007249:Inflammation / Q000097:blood
chemical_list: D000906:Antibodies; D052157:Aptamers, Nucleotide; D002097:C-Reactive Protein
keywords: Aptamer; C-reactive protein; Multi-Analyte Profiling (xMAP)