ABSTRACT
AIM: To establish a new chemiluminescent assay with high sensitivity for detecting E. coli O157:H7 in food. METHODS: The assay was established based on the alkaline phosphatase (ALP) labeled anti-E. coli O157:H7 antibody, which reacted with an excellent chemiluminescent reagent, 3(2' spiroadamantane)4 methoxy 4(3''phosphoryloxy) phenyl 1,2 dioxetane (AMPPD) buffer solution and emitted the photons. RESULTS: The sensitivity of chemiluminescence assay was 850, and the linear range was 1000-50,000. The intra- and interassay CV values (CVs) were respectively below 15% and 20%. The correlation coefficient was 0.9807 by comparing with the conventional counting method. CONCLUSION: The chemiluminescent immunoassay is more accurate than other methods in the detection of concentration of E. coli O157:H7 in samples.
Subject(s)
Escherichia coli O157/isolation & purification , Food Contamination , Luminescent Measurements/methods , Enzyme-Linked Immunosorbent Assay/methods , Escherichia coli O157/immunology , Food Contamination/prevention & control , Food Microbiology/standards , Immunoassay , Sensitivity and SpecificityABSTRACT
AIM: To establish a low cost and sensitive microbeads-based chemiluminescence immunoassay (CLEIA) for detecting human thyrotropin. METHODS: Thyrotropin in sera was captured by an alkaline phosphase-labeled mAb against TSH beta subunit and a FITC-labeled mAb against TSH alpha subunit. Captured thyrotropin was then isolated with immuno-magnetic beads conjugated with anti-FITC antibody and then quantified by chemiluminescence using adamanatane amine as luminescent substrate. RESULTS: The sensitivity of this assay is 0.004 mIU/L. The intra-assay CV and the inter-assay CV of the assay were 7.45% and 10.45%, respectively. The recovery rate was 91.4% -102.4%. The examination result of the assay correlates well with that of ACS-180 system. CONCLUSION: The CLELA for detecting TSH is low-cost, sensitive, specific and stable, and therefore may have a promising prospect in clinical application.
