Tomkins B A, Griest W H
J Chromatogr. 1987 Jan 16;386:103-10. doi: 10.1016/s0021-9673(01)94588-1.
Benzo[a]pyrene (BaP), a well-known carcinogen, is frequently measured as an "indicator" of the potential dermal tumorigenicity of a sample. The present sequential high-performance liquid chromatography--high-performance liquid chromatography method overcomes problems in trace-level sample enrichment and recovery corrections encountered earlier. An amount of 5 g of naphtha or fuel oil is diluted to 10 ml with dichloromethane and spiked with a small quantity (ca. 0.25 micrograms) of 14C-labeled BaP tracer. A BaP-enriched fraction is obtained from a 1-ml aliquot of this sample by semipreparative chromatography on a Partisil PAC 10 column with dichloromethane-hexane (10:90) as the eluent, and concentrated to exactly 0.3, 0.5, or 1.0 ml in acetonitrile. Quantitation is performed using a reversed-phase Vydac 201 TP 5415 column with acetonitrile-water (75:25) as eluent and a Waters Model 420 E/420 AC fluorescence detector, employing an excitation/emission filter pair of 360/425 nm. The recovery of the radiolabeled tracer is evaluated by combustion of 50 microliter of the final isolate in pure oxygen, collection of the liberated 14CO2 in an alkaline desorber, and liquid scintillation counting. The recovery of BaP normally exceeded 90%, but values as low as ca. 50% were occasionally observed. Potential matrix interferences in the recovery determination were eliminated by sample combustion. The nominal precision of the overall method is approximately +/- 30% relative standard deviation at a BaP concentration of 30 ppb. The nominal analysis time for a single sample is approximately 4 h.
苯并[a]芘（BaP）是一种著名的致癌物，常被用作样品潜在皮肤致癌性的“指标”进行测定。目前的高效液相色谱 - 高效液相色谱串联法克服了早期在痕量样品富集和回收率校正方面遇到的问题。取5克石脑油或燃料油，用二氯甲烷稀释至10毫升，并加入少量（约0.25微克）的14C标记的BaP示踪剂。取该样品1毫升等分试样，在Partisil PAC 10柱上以二氯甲烷 - 己烷（10:90）为洗脱剂进行半制备色谱，得到富含BaP的馏分，然后在乙腈中浓缩至恰好0.3、0.5或1.0毫升。使用反相Vydac 201 TP 5415柱，以乙腈 - 水（75:25）为洗脱剂，以及Waters Model 420 E/420 AC荧光检测器进行定量分析，激发/发射滤光片对为360/425纳米。通过在纯氧中燃烧50微升最终分离物、在碱性解吸器中收集释放的14CO2并进行液体闪烁计数来评估放射性标记示踪剂的回收率。BaP的回收率通常超过90%，但偶尔也会观察到低至约50%的值。通过样品燃烧消除了回收率测定中潜在的基质干扰。在BaP浓度为30 ppb时，该整体方法的标称精密度约为相对标准偏差±30%。单个样品的标称分析时间约为4小时。
