OBJECTIVETo establish chemiluminescence enzyme immunoassay (CLEIA) for quantitative detection of procollagen III N-terminal peptide (P III NP) in serum.

METHODSA sandwich reaction was preformed with horseradish peroxidase labeled monoclonal antibody of P III NP as the catalytic enzyme and the luminol as the luminescence reagent. Several reactions liquid's concentration and reaction conditions were optimized. The method was evaluated in all aspects such as linear range, sensitivity, specificity, stability and so on. The CLEIA was compared with imported ELISA kits, by detecting clinical serum.

RESULTSThe linear range was 0.8-85 ng/ml. The detection limit was 0.5 ng/ml. Inter-assay and intra-assay RSD were both less than 10%. The recoveries of three different spiked concentration samples were 96.2%, 91.2% and 101.1%. After stored at 4 degrees C and 37 degrees C for 3, 5, 7 days, the analysis showed correlation coefficient higher than 0.99 and RSD lower than 6%. The detected results of clinical sera with CLEIA closely corresponded to those with imported ELISA.

CONCLUSIONEstablished CLEIA for quantity determination of serum P III NP has high accuracy, sensitivity and repeatability.