高级检索

    超高效液相色谱-串联质谱法快速测定环境空气中13种醛酮类化合物的含量

    Rapid Determination of 13 Aldehydes and Ketones in Ambient Air by Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry

    • 摘要: 将两根2,4-二硝基苯肼(DNPH)采样管串联,前端连接一根除臭氧柱,采样25 min,用密封帽密封管口,于4℃以下保存。将DNPH采样管于25℃静置2 h,用5 mL乙腈洗脱,洗脱液流向与采样时气流方向相反。收集洗脱液,用乙腈稀释至5 mL,过0.22 μm滤膜,加入与滤液等体积的水,注入超高效液相色谱仪,在Shim-pack GISS色谱柱(50 mm×2.1 mm,1.9 μm)上用不同体积比的乙腈-水溶液进行梯度洗脱,分离得到的13种醛酮类化合物(甲醛、乙醛、丙酮、丙烯醛、丙醛、丁烯醛、丁醛、苯甲醛、戊醛、对甲基苯甲醛、己醛、甲基丙烯醛和丁酮)在串联质谱仪中以电喷雾离子源负离子模式电离,多反应监测模式检测,外标法定量。结果显示,13种醛酮类化合物的DNPH衍生物可在8 min内实现基线分离,且基质干扰小;标准曲线的线性范围均为0.005~0.20 mg·L-1,检出限(3.143s)为0.09~0.32 μg·m-3;分别进行精密度和回收试验,各目标物测定值的相对标准偏差(n=6)为0.90%~7.1%,回收率为81.8%~104%;方法用于环境空气样品的分析,检出了甲醛、乙醛、丙酮、丙烯醛、丙醛、丁醛和戊醛,检出量分别为5.24,5.52,31.2,11.8,3.42,7.10,4.27 μg·m-3

       

      Abstract: Two 2,4-dinitrophenylhydrazine (DNPH) sampling tubes were connected in series, and a deozonation column was connected to the front-end. After sampling for 25 min, the tube was sealed with a sealer, and stored below 4℃. The DNPH sampling tubes were settled at 25℃ for 2 h, and eluted with 5 mL of acetonitrile, with the flow direction of the eluate opposite to that of the air during sampling. The eluate was collected, diluted to 5 mL with acetonitrile, passed through a 0.22 μm filter membrane, mixed with an equal volume of water as the filtrate, and introduced into ultra-high performance liquid chromatograph. Gradient elution was performed on a Shim-pack GISS column (50 mm×2.1 mm, 1.9 μm) with acetonitrile-water solution at different volume ratios, and the 13 aldehydes and ketones (formaldehyde, acetaldehyde, acetone, acrolein, proponaldehyde, butenal, butyraldehyde, benzaldehyde, valeraldehyde, p-methylbenzaldehyde, hexanal, methylacrolein and butanone) were separated. The above compounds separated were ionized by tandem mass spectrometer with negative electrospray spray ion source mode, detected with multiple reaction monitoring mode, and quantified by external standard method. It was shown that the DNPH derivatives of the 13 aldehydes and ketones achieved baseline separation within 8 min with little matrix interference. The linear ranges of the standard curves were 0.005-0.20 mg·L-1, with detection limits (3.143s) in the range of 0.09-0.32 μg·m-3. Tests for precision and recovery were carried out, giving RSDs (n=6) of the determined values of each target in the range of 0.90%-7.1%, and recoveries ranged from 81.8% to 104%. The prescribed method was applied to the analysis of the ambient air sample, and formaldehyde, acetaldehyde, acetone, acrolein, proponaldehyde, butyraldehyde and valeraldehyde were detected, and the detected amounts were 5.24, 5.52, 31.2, 11.8, 3.42, 7.10, 4.27 μg·m-3, respectively.

       

    /

    返回文章
    返回