Quantification of cystatin C by time-resolved fluorometry-based immunoassays

►Competitive and non-competitive immunoassays for cystatin C developed and compared. ►Heterogeneous non-competitive assay showed best sensitivity and widest working range. ►Heterogeneous competitive assay had non-optimal working range and varying recoveries. ►Homogeneous competitive assay: rapid, simple protocol with optimal working range.