Two immunoassay formats for fully automated CRP detection in human serum

Immunoassays are a proven approach towards fast, sensitive, cost-effective and easy-to-use analytical systems which are able to measure a variety of interesting analytes, especially in medical diagnostics. Herein, we report two assay formats, binding inhibition and sandwich assay format, for detection of C-reactive protein (CRP) in human serum. Both assays were characterised and compared with respect to their suitability and adaption into a complete sensor system. An automated, optical biosensor system, based on evanescent field technology, was used to carry out a full threefold calibration in each case. Owing to the resulting working ranges, 0.044–2.9 mg L−1 and 0.13–22.9 mg L−1, respectively, the assays qualify for use in detecting high-sensitivity CRP (C-reactive protein).