Adaptation, Optimization, and Validation of HPLC-FLD for the Simultaneous Quantification of the Aflatoxins in Merkén

• HPLC-FLD was adapted, optimized, and validated to quantify aflatoxins in merkén. • Interferents were adequately eliminated with Tween 20 (10%) • LLOQ (1 ng g −1 ) were lower than international regulations. • The validated method is reliable for routine aflatoxin analysis in merkén. • Concentration levels in the range of 1.00–176 ng g −1 were quantified in merkén. Mycotoxin contamination in agro-food systems has become a serious global concern over the last decade. Several methods have been developed in recent years to detect aflatoxins (AFs) in single spices, although none have been developed for mixed spices like merkén. The present study adapted, optimized, and validated an analytical method for the extraction, purification, and quantification of total aflatoxins (AFs; B1, B2, G1, and G2) in merkén by high performance liquid chromatography with fluorescence detection (HPLC-FLD) and post-column derivatization. The results provide satisfactory AFs separation in an elution time of 21 min with a 10-µL injection loop. The method was linear (r > 0.98) over the concentration ranges of 0.6–6.2 ng g −1 (B2 and G2) and 1.96–20 ng g −1 (B1 and G1). The lower limits of detection (LLOD) and lower limits of quantification (LLOQ) for B1, B2, G1, and G2 were 0.3 and 1.0 ng g −1 , respectively. The recoveries of AFs in merkén ranged from 71% (G2) to 86% (B1) and were considered satisfactory for matrix fortifications of 0.99 (B1 and B2), 0.98 (G1), and 1.03 (G2), respectively. The intra-day precision ranged from 1.2 to 5.1% while the inter-day precision ranged from 3.7 to 14.9%. The uncertainty values calculated for the method at 1 ng g −1 (LLOQ) were 38, 25, 34, and 59% for B1, B2, G1, and G2, respectively. The method was successfully applied for AFs quantification in merkén (1.00–176 ng g −1 ). The calculated EDI values were lower than the limits proposed by the European Union (0.93–2.451 ng kg −1 bw day −1 ) and the United States (2.7 ng kg −1 bw day −1 ) and were not indicative of a health risk to consumers. This is the first study to describe the development and validation of a method for AFs quantification in merkén, which is important for future quality monitoring efforts of this mixed spice.