Scott P M, Trucksess M W
Health Canada, Health Protection Branch, Food Research Division, Sir Frederick G. Banting Research Centre, Ottawa, ON, Canada.
J AOAC Int. 1997 Sep-Oct;80(5):941-9.
Immunoaffinity columns (IACs) are widely used for cleanup and isolation of mycotoxins extracted from foods and biological fluids, particularly aflatoxins, ochratoxin A, and fumonisins. The columns are prepared by binding antibodies specific for a given mycotoxin to a specially activated solid-phase support and packing the support suspended in aqueous buffer solution into a cartridge. The mycotoxin in the extract or fluid binds to the antibody, impurities are removed with water or aqueous solution, and then the mycotoxin is desorbed with a miscible solvent such as methanol. Further separation can be performed with IAC, followed by liquid chromatographic (LC) quantitation, either off-line or on-line in an automated system, or by fluorometry. IACs have been used by laboratories that developed the antibodies but are also available commercially for aflatoxins, ochratoxin A, fumonisins, zearalenone, and deoxynivalenol. Among commercial IACs, Aflatest P is used as the cleanup step in an LC method and in a solution fluorometry method for corn, peanuts, and peanut butter that was adopted as an AOAC INTERNATIONAL Official Method after evaluation by an international collaborative study. As part of a fluorometer-based test kit, aflatest P was further certified by the AOAC Research Institute to measure total aflatoxins in 10 grains and grain products. IACs can concentrate the analyte from a large amount of sample, allowing detection limits at low parts-per-trillion levels in some cases (e.g., for aflatoxin M1 and ochratoxin A in liquid food matrixes). Regeneration of IACs for reuse in aflatoxin, ochratoxin A, fumonisin, and zearalenone analyses has been investigated.
免疫亲和柱（IAC）被广泛用于从食品和生物体液中提取的霉菌毒素的净化和分离，特别是黄曲霉毒素、赭曲霉毒素A和伏马毒素。这些柱子是通过将针对特定霉菌毒素的抗体与经过特殊活化的固相支持物结合，并将悬浮在水性缓冲溶液中的支持物装填到柱管中制备而成。提取物或液体中的霉菌毒素与抗体结合，用水或水溶液去除杂质，然后用甲醇等可混溶溶剂解吸霉菌毒素。可通过IAC进行进一步分离，随后进行液相色谱（LC）定量分析，可离线或在自动化系统中在线进行，也可通过荧光法进行。开发抗体的实验室使用过IAC，但黄曲霉毒素、赭曲霉毒素A、伏马毒素、玉米赤霉烯酮和脱氧雪腐镰刀菌烯醇的IAC也有商业供应。在商业IAC中，Aflatest P被用作一种LC方法和一种溶液荧光法中的净化步骤，用于玉米、花生和花生酱，该方法经国际协作研究评估后被采纳为AOAC INTERNATIONAL官方方法。作为基于荧光计的检测试剂盒的一部分，Aflatest P经AOAC研究所进一步认证，可用于测量10种谷物和谷物产品中的总黄曲霉毒素。IAC可以从大量样品中浓缩分析物，在某些情况下可实现万亿分之一低水平的检测限（例如，对于液态食品基质中的黄曲霉毒素M1和赭曲霉毒素A）。已经对用于黄曲霉毒素、赭曲霉毒素A、伏马毒素和玉米赤霉烯酮分析的IAC再生以重复使用进行了研究。
