色谱 ›› 2019, Vol. 37 ›› Issue (2): 239-245.DOI: 10.3724/SP.J.1123.2018.09039

• 技术与应用 • 上一篇    

在线固相萃取-液相色谱法直接测定水中超痕量多环芳烃

王超1, 黄肇章2, 邢占磊3, 陈烨1, 于建钊1, 刘方1, 袁懋1   

  1. 1. 中国环境监测总站, 北京 100012;
    2. 广州市环境监测中心站, 广州 510091;
    3. 赛默飞世尔科技有限公司, 北京 100080
  • 收稿日期:2018-09-29 出版日期:2019-02-09 发布日期:2014-12-31
  • 通讯作者: 王超,Tel:(010)84943198,E-mail:preparing@126.com

Direct determination of ultra-trace polycyclic aromatic hydrocarbons in water by liquid chromatography coupled with online solid phase extraction

WANG Chao1, HUANG Zhaozhang2, XING Zhanlei3, CHEN Ye1, YU Jianzhao1, LIU Fang1, YUAN Mao1   

  1. 1. China National Environmental Monitoring Centre, Beijing 100012, China;
    2. Guangzhou Environmental Monitoring Centre, Guangzhou 510091, China;
    3. Thermo Fisher Scientific Corporation China, Beijing 100080, China
  • Received:2018-09-29 Online:2019-02-09 Published:2014-12-31

摘要:

建立了在线固相萃取-液相色谱直接测定水体中16种超痕量多环芳烃(PAHs)的方法。水样经高速离心后,加入适量甲醇,配制成40%(体积分数)甲醇水溶液,直接进样2 mL至在线固相萃取流路,进行萃取富集,再通过阀切换将洗脱的PAHs转移至分析流路进行分离检测。16种PAHs在各自范围内线性关系良好,相关系数均大于0.996;方法的检出限为0.14~12.50 ng/L,其中苯并[a]芘(B(a)P)的检出限为0.38 ng/L。实际水样在10、40和200 ng/L加标水平下的加标回收率为76.1%~134.9%,RSD为0.3%~16.6%。B(a)P在1 ng/L加标水平下的回收率为71.8%~92.7%,RSD为3.9%。结果表明,该方法操作简单,灵敏度高,溶剂消耗量少,可满足水样中PAHs,尤其是B(a)P的超痕量分析要求。

关键词: 苯并[a]芘, 多环芳烃, 水样, 液相色谱, 在线固相萃取

Abstract:

A method was developed for the direct determination of 16 ultra-trace polycyclic aromatic hydrocarbons (PAHs) in water by liquid chromatography (LC) coupled with online solid phase extraction (online SPE). The water sample was centrifuged at a high speed to remove the particulate matter and prepared into an aqueous solution containing 40% (v/v) methanol. A 2 mL-sample was directly injected into the online SPE flow path. Online purification and enrichment of the samples were carried out on the SPE column (Acclaim PA Ⅱ, 50 mm×4.6 mm, 3 μm). The PAHs eluted from the SPE column were transferred to the analytical flow path by valve switching, and were separated on a Hypersil Green PAHs column (150 mm×3 mm, 3 μm). Water and acetonitrile were used as the mobile phases. The flow rates of 1.0 mL/min and 0.4 mL/min were used in the extraction and balance processes, respectively. The flow rate of 0.6 mL/min was used to separate the PAHs in the analytical flow path. Acenaphthylene without a fluorescent signal was detected at the ultraviolet absorption wavelength of 220 nm, while other PAHs were measured by the fluorescence signal via the special excitation/emission wavelength program. The entire analysis could be completed within 37 min. The linear correlation coefficients of the 16 PAHs were greater than 0.996. The limits of detection of the PAHs were 0.14-12.50 ng/L (S/N=3) with only 0.38 ng/L for benzo(a)pyrene (B(a)P). The recoveries of PAHs at spiked levels of 10, 40 and 200 ng/L in the water samples were 76.1%-134.9%. The RSDs (n=3) were 0.3%-16.6%. Furthermore, the recoveries and RSDs (n=3) of B(a)P were 71.8%-92.7% and 3.9%, respectively. The proposed method is simple, rapid, solvent-saving, stable and sensitive, and can meet the ultra-trace analysis requirements of the PAHs (especially B(a)P) in various water samples.

Key words: benzo(a)pyrene (B(a)P), liquid chromatography (LC), online solid phase extraction (online SPE), polycyclic aromatic hydrocarbons (PAHs), water

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