Rapid one-step whole blood C-reactive protein magnetic permeability immunoassay with monoclonal antibody conjugated nanoparticles as superparamagnetic labels and enhanced sedimentation
A rapid (5.5 min) one-step whole blood C-reactive protein (CRP) magnetic permeability immunoassay utilizing monoclonal antibody conjugated dextran iron oxide nanoparticles (70 nm) as superparamagnetic labels and mixed fractions (1:1 ratio of 15-40 and 60 μm) of polyclonal anti-CRP conjugated silica...
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Published in | Analytical and bioanalytical chemistry Vol. 384; no. 3; pp. 651 - 657 |
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Main Authors | , , , , |
Format | Journal Article |
Language | English |
Published |
Germany
Berlin/Heidelberg : Springer-Verlag
01.02.2006
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Subjects | |
Online Access | Get full text |
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Summary: | A rapid (5.5 min) one-step whole blood C-reactive protein (CRP) magnetic permeability immunoassay utilizing monoclonal antibody conjugated dextran iron oxide nanoparticles (70 nm) as superparamagnetic labels and mixed fractions (1:1 ratio of 15-40 and 60 μm) of polyclonal anti-CRP conjugated silica microparticles for enhanced sedimentation is described. In this one-step assay procedure, a whole blood sample (4 μl) is applied to an assay glass vial, containing both antibody conjugates, and mixed for 30 s. The target analyte, CRP, forms a sandwich complex between the conjugated nanoparticles and microparticles, and, subsequently, the complex sediments under normal gravitation within 5 min to the bottom of the vial. The magnetic permeability increase of the sediment due to the presence of the complexed superparamagnetic nanoparticles is determined using an inductance-based transducer. Assayed patient whole blood samples were compared with the Abbott Diagnostics Architect reference method. A strong linear correlation was observed for the CRP concentration range 0-260 mg/l in whole blood (y=1.001x+0.42, R ²=0.982, n=50). The CRP assay presented showed a limit of detection of 3 mg/l and a total imprecision (coefficient of variation) of 10.5%. On the basis of our observations, we propose a rapid, one-step, CRP assay for near-patient testing. |
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Bibliography: | http://dx.doi.org/10.1007/s00216-005-0094-6 ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 |
ISSN: | 1618-2642 1618-2650 |
DOI: | 10.1007/s00216-005-0094-6 |