Aflatest wb sr

The stock solution of aflatoxins was purchased from Sigma-Aldrich (St Louis, MO, USA) and consisted of a mix with 1 µg AFB1, 0.3 µg AFB2, 1 µg AFG1, and 0.3 µg AFG2 in methanol. Calibration curves for aflatoxins B1, B2, G1, and G2 were prepared at concentrations of 0.5, 1, 2.5, 5, and 10 ng/mL for AFB1 and AFG1 and 0.25, 0.5, 0.7, 1.5, and 3 ng/mL for AFB2 and AFG2. An intermediate solution for aflatoxins was made by 100-fold dilution of the original mix; then, working calibration solutions were prepared with mobile phase, stored at 4 °C, and renewed every week. Stock and intermediate standard solutions were stored at –20 °C. The immunoaffinity column (IAC) AflaTest WB SR was acquired from VICAM (Watertown, MA, USA). Deionized water was obtained from a Millipore milli-Q water purification system (Mildford, MA, USA). HPLC-grade acetonitrile and methanol were supplied from Scharlau (Scharlab, Barcelona, Spain), and sodium chloride was purchased from Panreac (Barcelona, Spain).
As a safety note, all used laboratory glassware were treated with an aqueous solution of sodium hypochlorite (5%) before discarding to minimize health risks due to mycotoxin contamination [18 (link)].

Stock solutions of aflatoxin B1 and M1 were purchased from Sigma-Aldrich (St. Louis, MO, USA) and consisted of 2 μg/mL of AFB1 and 0.5 μg/mL of AFM1 in acetonitrile, respectively. Calibration curves for AFB1 and AFM1 were prepared at concentrations of 0.25, 0.5, 1, 2.5 and 5 ng/mL for AFB1 and 0.025, 0.050, 0.075, 0.100, 0.150 and 0.200 ng/mL for AFM1. Working calibration solutions were prepared with mobile phase, stored at 4 °C and renewed every week. The immunoaffinity columns (IAC) AflaTest WB SR and Afla M1 were acquired from VICAM (Watertown, MA, USA). Deionized water was obtained from a Millipore milli-Q water purification system (Mildford, MA, USA). HPLC-grade acetonitrile and methanol were supplied from Scharlau (Scharlab, Barcelona, Spain) and sodium chloride was purchased from Panreac (Barcelona, Spain). Certified reference materials from Biopure (Romer, Getzersdorf, Austria) were used for method validation: maize flour contaminated with AFB1 (QCM1C2, level 8.8 μg/kg ± 3.1 μg/kg) and milk powder contaminated with AFM1 (ERMBD 284, level 0.44 μg/kg ± 0.06 μg/kg).