Simultaneous analysis of mycotoxins in corn flour using LC/MS-MS combined with a modified QuEChERS procedure

Abstract

The present study was developed to simultaneously quantify different mycotoxins including zearalenone (ZEA), T2-toxin, aflatoxin B1 (AFB1), deoxynivalenol (DON), and ochratoxin A (OTA) in 30 and 10 corn flour samples collected from local gristmill corn in Ardabil province and local markets in Tehran, respectively. A modified method QuEChERS (quick, easy, cheap, effective, rugged, and safe) in combination with an LC-MS/MS technique was used for sample preparation and measuring the levels of mycotoxins, respectively. Spiked calibration curves based on external and internal standards were used to overcome matrix effects and were reported as linear between 2 and 50 ng g−1 for aflatoxin B1, T-2 toxin, ochratoxin A; 50 and 1250 ng g−1 for zearalenone; and 75 and 1800 ng g−1 for deoxynivalenol. With the aid of spike calibration curves and acidic condition, the absorption of OTA by primary, secondary amine was reduced, and consequently, the percentage of recoveries was improved (in the range of 92.98–103.8). AFB1, OTA, and ZEA were detected and quantified in 23 (76.6%), 6 (20%), and 14 (46%) of 30 samples, with average contamination of 154.1 ng g−1, 25 ng g−1, and 358.7 ng g−1, respectively. The co-occurrence of AFB1 + ZEA and AFB1 + OTA + ZEA was noted in 20% and 23% of corn samples, respectively. The measured level of contamination for DON and T-2 toxin of corn flour samples did not exceed the maximum tolerated level. Moreover, the estimation of dietary intake of AFB1, OTA, ZER, DON, and T2-toxin were 5.8, 1.1, 32.1, 5.58, and 0.06 ng per kg body weight per day, respectively.