Simultaneous Rapid Detection of Aflatoxin B₁ and Ochratoxin A in Spices Using Lateral Flow Immuno-Chromatographic Assay

Abstract

Spices are susceptible to contamination by aflatoxin B1 (AFB1) and ochratoxin A (OTA), which are both mycotoxins with high toxicity and carcinogenicity. In this study, we aimed to develop an immuno-chromatographic strip test for the simultaneous quantification of AFB1 and OTA in spices by spraying the coupled antigens AFB1–ovalbumin (AFB1–OVA) and OTA–ovalbumin (OTA–OVA) on a nitrocellulose membrane. The test strip had high sensitivity, good specificity, and strong stability. The detection limits of these two mycotoxins in Chinese prickly ash, pepper, chili, cinnamon, and aniseed were 5 μg/kg. The false positivity rate was 2%, and the false negativity rate was 0%. The maximum coefficient of variation was 4.28% between batches and 5.72% within batches. The average recovery rates of AFB1 and OTA in spices were 81.2–113.7% and 82.2–118.6%, respectively, and the relative standard deviation (RSD) was 1 and OTA in spices. This method would allow the relevant regulatory agencies to strengthen supervision in an effort to reduce the possible human health hazards of such contaminated spices.

Keywords

• aflatoxin B₁
• ochratotoxin A
• gold immuno-chromatography assay
• spice
• detection method