Validation of I'screen AFLA M1 Milk for Detection of Aflatoxin M1 in Raw Bovine Milk and Powdered Milk: AOAC Performance Tested MethodSM 072002.

Background: Aflatoxin M1 (AFM1) is the major metabolite of Aflatoxin B1 (AFB1) and can be found in the milk of animals fed with feed containing AFB1. The frequency of occurrence of AFM1 in milk has led to the development of specific quantitative methods of analysis to mitigate the risk of adversely affecting human health.

Objective: To demonstrate that the I'screen AFLA M1 Milk ELISA kit can quantify AFM1 in raw bovine milk and powdered milk.

Method: Assay performance was evaluated studying lot-to-lot consistency, assay stability, robustness, and possible interferences of related molecules. Raw bovine milk samples spiked at 0, 5.0, 20, 50, 100, and 200 ng/L of AFM1 and powdered milk reference materials and spiked samples at 100 and 200 ng/L were tested to determine recovery, repeatability, and bias. LOD and LOQ were also determined for both matrices.

Results: High selectivity for AFM1 was demonstrated and performances were consistent, robust, and stable. The LOQ was validated at 5 ng/L for raw milk and 50 ng/L for powdered milk. Recoveries for spiked raw and powdered milk were 97-122%, with RSDr < 10%, and 106-111% for reference materials, with RSDr < 5%.

Conclusions: The data collected validate the method as a selective, specific, sensitive, accurate, and precise tool for the analysis of AFM1 in raw bovine milk and powdered milk.

Highlights: We demonstrated that I'screen AFLA M1 is a reliable kit and a proper screening tool suitable for high analytical throughputs.