Abstract:

An indirect competitive chemiluminescent enzyme immunoassay (CLEIA) was developed for the detection of
Sudan Ⅰ in food products. The CLEIA conditions including molar ratio of coating antigen to carrier, antigen concentration,
and dilution ratio of antibody were optimized. In the standard curve of the optimized CLEIA, the linear range was 0.156–
5 ng/mL, the half maximal inhibitory concentration (IC50) was 0.679 ng/mL and the limit of detection (LOD) was
0.078 9 ng/mL. The CLEIA showed good recoveries with spiked chili powder ranging from 75.08% to 112.18%. Compared
with ELISA method, the IC50 values of CLEIA was reduced by 30%. The proposed method has a high sensitivity.

Key words: Sudan Ⅰ, chemiluminescent enzyme immunoassay (CLEIA), enzyme-linked immunosorbent assay (ELISA)