Abstract:

Six sample pretreatment methods for colloidal gold-based immunochromatographic detection of chloranphenicol in honey were compared through colour observation of the test strip with the naked eye and detection of chloranphenicol recovery rate with image analyzer and with ELISA kit, combined with the characteristics of immunochromatographic test strip. The results showed that the highest recovery rate of chloranphenicol can be achieved by the following pretreatment method: weighing 4 g of samples into 15-ml centrifuge tube, and then adding 2 ml of distilled water and oscillating vigorously to make the honey fully dissolved; adding 8 ml of ethyl acetate, and then overturned oscillating for 8 min; standing the tube until the upper organic phase clarified; aspirating 5 ml of organic solvents into the 5-ml centrifuge tube, and then blow-drying it with hair dryer; adding 160  μl of PBST buffer to dissolve residue, and then adding 1 ml of hexane and oscillating fully; standing the tube, and then aspirating the lower water layer to detect chloranphenicol.

Key words: honey, gold-based immunochromatographic assay, chloramphenicol, pretreatment, ELISA