Colloidal Gold Immunochromatographic Strip Assay for the Detection of Azaperone in Pork and Pork Liver

Abstract

In this study, a highly sensitive and specific monoclonal antibody (mAb) against azaperone was produced. The mAb belonged to the IgG2b subtype and its half maximal inhibitory concentration (IC 50 ) was 0.46 ng/mL. The limit of detection value was 0.081 ng/mL and the linear range (IC 20 −IC 80 ) was 0.165−1.29 ng/mL. Based on this anti-azaperone mAb, a colloidal gold immunochromatographic strip assay method was established for the detection of azaperone in pork and pork liver samples. For pork samples, the cutoff value of the colloidal gold immunochromatographic strip assay was 10 ng/g, and the cutoff value was also 10 ng/g in pig liver samples. This colloidal gold immunochromatographic strip assay is a rapid, simple, and practical method for the detection of azaperone in pork and pork liver samples available in markets.

Highly sensitive immunochromatographic assay for simultaneous determination of azaperone and azaperol in pork

“…3 (b), the linear equation of mAb against AZN and AZL was y = −0.32947 x + 0.3508 ( R 2 = 0.9916) and y = −0.35707 x + 0.31694 ( R 2 = 0.9919), respectively. It was worth noting that the IC 50 of AZN and AZL was 0.35 and 0.31 ng/mL which is lower than that reported ( Lin et al, 2020 ). It indicated that the sensitivity of mAb for AZN was higher than that before.…”

“…It is well known that the design of hapten and the preparation of antigen are the keys to obtain mAb with high quality. In previous study, Lin et al prepared the hapten by introducing a linker arm containing four carbon atoms and an active carboxyl group to the benzene ring of AZL, which is then linked with KLH to synthesize the immunogen ( Lin et al, 2020 ). However, the CR value to AZL of the mAb obtained by the hapten was <2.5 % influenced by the mode and location of hapten binging to carrier protein.…”

“…However, AZN is usually illegally added for improving fodder conversion rate by reducing animal activity, which can promote weight gain. The accumulation of AZN in edible animal tissues is caused by the improper use of drug dosage or non-observance of withdrawal period ( Oliveira et al, 2017 ), which thus cause damage to the health of consumers through the food chain to result in heart rate reduction, skin vasodilation, cardiovascular effects and so on ( Lin, Wu, Cui, Song, Kuang, & Xu, 2020 ). It is worth noting that azaperol (AZL), the main metabolite of AZN, can be used as the marker residue to screen AZN ( Rauws, Olling, Freudenthal, & Ham, 1976 ).…”

“…Notably, the most important components are molecular recognition element and the signal transduction element in ICA ( Liu et al, 2015 , Majdinasab et al, 2019 ). At present, only one literature has reported the detection of AZN by ICA method ( Lin et al, 2020 ). However, the reported monoclonal antibody (mAb), a molecular recognition element, was unable to detect AZN and AZL simultaneously due to its weak cross-reactivity (CR) with AZL.…”

A gold-based immunochromatographic strip for the detection of sirolimus in human whole blood

“…Mouse spleens were dissected for cell fusion which was performed as previously reported. [32][33][34] On the seventh day after fusion, cell lysates from the hybridoma cells were added to 96-well plates and were screened by ic-ELISAs, and then subcloned three times. The resulting ascites were collected and purified as previously described.…”