Development of a sensitivity-improved immunoassay for the determination of carbaryl in food samples

✍ Scribed by Tingting Dong; Jingwei Sun; Bing Liu; Yan Zhang; Yang Song; Shuo Wang

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 118 KB
• Volume: 90
• Category: Article
• ISSN: 0022-5142
• DOI: 10.1002/jsfa.3917

✦ Synopsis

BACKGROUND: With the aim of developing a highly sensitive immunoassay for carbaryl, a hapten which had high similarity to carbaryl was synthesised using a safer and more practical approach. After it was conjugated to horseradish peroxidase, direct competitive heterologous enzyme-linked immunosorbent assay (CD-ELISA) was optimised and characterised. The assay performance conditions were investigated in details. Enhanced chemiluminescence ELISA (ECL-ELISA) was also used in preliminary studies.

RESULTS:

The assay obtained an IC 50 value (the concentration causing 50% inhibition) of 2 µg kg -1 , which was 12-fold more sensitive than previous results of homologous CD-ELISA. In ECL-ELISA, the IC 50 was further decreased 10-fold to 0.2 µg kg -1 . The CD-ELISA developed was applicable for broad conditions, and could be applied on various food samples with a more convenient pre-treatment. Average recoveries were in a range of 88.3-101.7%. The results correlated well with those obtained using high-performance liquid chromatography (HPLC) analysis (R 2 = 0.989).

CONCLUSION:

The ELISA developed was a great improvement in the determination of carbaryl, showing that the immunoassay developed was a simple, rapid and efficient method that was reliable for the detection of carbaryl and suitable for rapid quantitative or qualitative determination in food samples.