Joe F L, Salemme J, Fazio T
J Assoc Off Anal Chem. 1982 Nov;65(6):1395-402.
A simple, rapid method has been developed for the separation and determination of polynuclear aromatic hydrocarbons (PAHs) in barley malt. An ultrasonic-cyclohexane extraction method was used to separate the PAHs from ground barley malt. The cyclohexane extracts were purified by chromatography through a water-deactivated silica gel-alumina column. The eluate from the column was concentrated and purified further by partitioning between dimethyl sulfoxide (DMSO) and cyclohexane. The DMSO extract was diluted with water and the PAHs were extracted back into cyclohexane. The cyclohexane extract was washed with water, dried through sodium sulfate, and evaporated, and the resulting residue was dissolved in 80% aqueous acetonitrile-methanol (1 + 1) and subjected to reverse phase high performance liquid chromatography. Thirty barley malt samples were analyzed using this procedure. Peaks having the same retention time as the carcinogen benzo(a)pyrene were isolated from 18 of the samples, and were equivalent to trace levels ranging from less than 0.1 to 0.2 ppb. Average recoveries of 11 PAHs, including benzo(a)pyrene, benzo(b)fluoranthene, indeno(1,2,3-cd)pyrene, and benz(a)anthracene, added to 25 g samples at 2.5 and 5 ppb, ranged from 78 to 97%, with a mean relative standard deviation of 6.6%.
已开发出一种简单、快速的方法用于分离和测定大麦芽中的多环芳烃（PAHs）。采用超声 - 环己烷萃取法从研磨后的大麦芽中分离PAHs。环己烷萃取物通过水失活硅胶 - 氧化铝柱进行色谱纯化。柱洗脱液经浓缩后，通过在二甲基亚砜（DMSO）和环己烷之间分配进一步纯化。DMSO萃取物用水稀释，PAHs再萃取回环己烷中。环己烷萃取物用水洗涤，经无水硫酸钠干燥并蒸发，所得残渣溶解于80%乙腈 - 甲醇水溶液（1 + 1）中，然后进行反相高效液相色谱分析。使用该方法分析了30个大麦芽样品。在18个样品中分离出了与致癌物苯并(a)芘保留时间相同的峰，其含量相当于痕量水平，范围从小于0.1至0.2 ppb。添加到25 g样品中浓度为2.5和5 ppb的11种PAHs（包括苯并(a)芘、苯并(b)荧蒽、茚并(1,2,3 - cd)芘和苯并(a)蒽）的平均回收率为78%至97%，平均相对标准偏差为6.6%。
