经剪碎和粉碎的印刷电路板样品用甲酸-甲醇(0.1+99.9)溶液超声提取,所得提取液于45 ℃旋转蒸发至1 mL,加水5 mL,用稀甲酸或稀氨水调节溶液的pH值为4~5。将溶液通过Oasis WAX固相萃取小柱净化,用甲酸(2+98)溶液和甲醇先后清洗小柱后,用氨水-甲醇(2+98)混合溶液洗脱,将全部洗脱液氮吹蒸发至近干,用流动相溶液定容为1 mL供测定。所用色谱柱为Acquity UPLC BEH C18柱,柱温30 ℃,进样量为5 μL。由5 mmol·L-1乙酸铵溶液及乙腈(60+40)混合溶液作为流动相,在0.3 mL·min-1流量条件下进行洗脱。质谱测定中采用ESI负电离方式,多反应监测扫描模式。测得全氟辛烷磺酸盐质量分数在1.0~1 000 μg·kg-1范围内与峰面积值呈线性关系,测定下限(10S/N)为1.0 μg·kg-1。用标准加入法测得回收率在89.0%~99.3%之间。

An appropriate amount of cut and crushed printed circuit board (PCB) sample was taken and extracted with HCOOH-CH3OH(0.1+99.9) mixture ultrasonically. The extract was evaporated to ca. 1 mL in a rotary evaporator at 45 ℃, 5 mL of H2O was added and the pH value of the solution was adjusted to 4-5 with dil. formic acid and dil. aq. ammonia. The solution was then purified by passing through the Oasis WAX SPE micro column and eluting with mixture of NH3(aq.)+CH3OH(2+98). The eluate was blown with N2 to near-dryness, and made up its volume to 1 mL with the mobile phase solution mentioned below. An aliquot of 5 μL of the sample was introduced for analysis. The Acquity UPLC BEH C18 column with column temp. of 30 ℃ was used for chromatographic separation, using a mixture of 5 mmol·L-1 NH4OAc solution and acetonitrile(60+40) as mobile phase for elution (flow-rate: 0.3 mL·min-1). ESI with negative ionization mode and scanning mode of MRM were used in the MS/MS analysis. Linearity range for perfluoro-octane sulfonate was found between 1.0-1 000 μg·kg-1. Lower limit of determination (10S/N) was found to be 1.0 μg·kg-1. Values of recovery found by standard addition method were in the range of 89.9%-99.3%.