Shotwell O L, Holaday C E, Athnasios A K, Ayres J L, Baxley J R, Bean G A, Chisholm T, Edds G T, Erickson R, Holaday C E, Johnson H S, Lowie D M, Minyard J P, Nesheim S, Rashmawi K J, Romer T R, Shannon G M, Soloman W, Teague R T, Wilson D M
J Assoc Off Anal Chem. 1981 May;64(3):674-7.
The Holaday-Velasco method and a modified Holaday method have been compared. The former method combines the speed and simplicity of the Holaday extraction and cleanup with the sensitivity of the minicolumn originally described by Velasco. The combination method has been approved by the AOAC and the AACC for determining aflatoxin in corn. The Holaday method was modified by substituting toluene for benzene in the solvent partition, and methylene chloride for chloroform in the minicolumn development to eliminate use of hazardous solvents. The neutral alumina in the Holaday minicolumn was changed from activity V to activity III to provide a more stable column. At aflatoxin levels in raw peanuts of 13-20 ng/g, the presence of aflatoxin was missed by the modified Holaday method in 4 analyses (3 laboratories) of 42 reported. There were no misses in this contamination range by the Holaday-Velasco method. There were no misses by either method with samples containing greater than 20 ng total aflatoxins/g. Analysis of uncontaminated raw peanuts by the modified Holaday method resulted in 2 false positives of 14 reports; the Holaday-Velasco method produced no false positive reports from 15 analyses of uncontaminated peanuts. The Holaday-Velasco method was adopted official first action for peanuts.
已对霍拉迪 - 贝拉斯科方法和改良的霍拉迪方法进行了比较。前一种方法将霍拉迪提取和净化的速度与简便性与最初由贝拉斯科描述的微柱的灵敏度相结合。该组合方法已获美国官方分析化学师协会（AOAC）和美国谷物化学家协会（AACC）批准用于测定玉米中的黄曲霉毒素。对霍拉迪方法进行了改良，在溶剂分配中用甲苯替代苯，在微柱展开中用二氯甲烷替代氯仿，以避免使用危险溶剂。霍拉迪微柱中的中性氧化铝活性从V级改为III级，以提供更稳定的柱子。对于生花生中黄曲霉毒素含量为13 - 20 ng/g的情况，在42份报告的4次分析（3个实验室）中，改良的霍拉迪方法有4次未检测到黄曲霉毒素的存在。在这个污染范围内，霍拉迪 - 贝拉斯科方法没有漏检情况。对于总黄曲霉毒素含量大于20 ng/g的样品，两种方法均未出现漏检情况。用改良的霍拉迪方法分析未受污染的生花生，在14份报告中有2例假阳性；用霍拉迪 - 贝拉斯科方法对15份未受污染的花生进行分析，未产生假阳性报告。霍拉迪 - 贝拉斯科方法被首次作为官方方法用于花生检测。
