A Sensitive Two-Analyte Immunochromatographic Strip for Simultaneously Detecting Aflatoxin M1 and Chloramphenicol in Milk.

Shih-Wei Wu,Feng-Yih Yu,Biing-Hui Liu,Jiunn-Liang Ko

doi:10.3390/toxins12100637

Abstract

A two-analyte immunochromatographic strip (immunostrip) was developed for the simultaneous detection of aflatoxin M1 (AFM1) and chloramphenicol (CAP) in milk. Protein conjugates (AFM1-ovalbumin (OVA) and CAP-OVA) and goat anti-rabbit IgG were respectively drawn on nitrocellulose membrane as two test lines (T1 and T2) and a control line (C). The immunostrip was dipped into a well that contained a 200 μL milk sample, 5 μL AFM1 antibody-gold conjugates, and 8 μL CAP antibody-gold conjugates; the whole assay was completed in 15 min and the results could be interpreted visually or using a reader. This immunostrip has cut-off levels of 0.1 ng/mL and 0.5 ng/mL for AFM1 and CAP, respectively. Analysis of CAP and AFM1 in milk samples revealed that data from the immunostrip test agreed closely with those obtained from ELISA. The two-analyte immunostrip is a rapid way for on-site simultaneous detection of AFM1 and CAP in milk.

Highlights

Milk is consumed in daily life to provide essential nutrients for humans
Aflatoxin M1, a hydroxylated metabolite of aflatoxin B1 (AFB1), is a frequently contaminant in dairy products since it remains stable during the whole process of milk pasteurization [1,2]
Polyclonal antibodies specific to aflatoxin M1 (AFM1) or CAP were used to establish dcELISAs

Summary

Introduction

Milk is consumed in daily life to provide essential nutrients for humans. Increasing concern about food safety has led to a growth in anxiety about the contamination of milk with mycotoxins or drug residues, such as aflatoxin M1 (AFM1) and chloramphenicol (CAP).Aflatoxin M1, a hydroxylated metabolite of aflatoxin B1 (AFB1), is a frequently contaminant in dairy products since it remains stable during the whole process of milk pasteurization [1,2].Previous studies have demonstrated that consumption of AFM1 through milk products is an important health issue to human, especially young individuals [3,4]. Increasing concern about food safety has led to a growth in anxiety about the contamination of milk with mycotoxins or drug residues, such as aflatoxin M1 (AFM1) and chloramphenicol (CAP). Aflatoxin M1, a hydroxylated metabolite of aflatoxin B1 (AFB1), is a frequently contaminant in dairy products since it remains stable during the whole process of milk pasteurization [1,2]. Previous studies have demonstrated that consumption of AFM1 through milk products is an important health issue to human, especially young individuals [3,4]. Numerous countries have set legal regulations on AFM1 levels in milk products. The United States Food and Drug Administration (FDA) and the European Union (EU) restrict the concentrations of AFM1 in milk to 0.5 ng/mL and

Methods

Results

Conclusion