稳定性同位素内标-吹扫捕集-气相色谱-质谱联用分析水中硫化物  

Determination of Sulfide in Water by Purge and Trap GC-MS Coupled with Stable Isotope Internal Standard

作　　者：林麒[1] 李俊荣[1] 林坚[1] 林国斌[1] 

机构地区：[1]福建省人兽共患病研究重点实验室福建省疾病预防控制中心,福州350001

出　　处：《分析化学》2014年第5期678-682,共5页Chinese Journal of Analytical Chemistry

基　　金：福建省疾病预防控制中心青年科研课题基金资助项目(No.2011-07)

摘　　要：建立稳定性同位素内标-吹扫捕集-气相色谱-质谱联用法（ GC-MS）分析多种水体中硫化物,为预警异味水质突发事件和开展相关研究奠定基础。水样脱氯过滤后,加入同位素内标与氯化钠,吹扫捕集装置40℃氮气吹扫10 min,200℃脱附2 min,吹扫流量40 mL/min。色谱柱：DB-624,进样口温度270℃,分流比20：1,载气高纯He,流速3.8 mL/min。升温条件：35℃（5 min）,6℃/min升至120℃,20℃/min升至210℃。传输线（ AUX）温度为280℃。质谱条件：离子源温度230℃,四极杆温度150℃,电子能量70 eV。以保留时间和质谱全扫描方式进行定性分析,质量范围m/z 45~450；选择离子监测定量；基质加标验证方法的准确度与精密度。乙硫醇、二甲基硫和二甲基二硫在0.6~21.3μg/L范围内线性良好。 ET, DMS和DMDS的检出限分别为0.088,0.13和0.10μg/L。5种水体高、低浓度加标,回收率为90.7%~118.0%, RSD为2.7%~9.8%。本方法采用稳定同位素内标法,具有较好的准确性、稳定性和实用性,可用于地表水、地下水和生活饮用水等多种水体中含硫嗅味物质的分析。A stable isotope internal standard-purge and trap-GC-MS analytical method of sulfides in a variety of water was established for the early warning odor water emergencies and researches. Water samples were dechlorinated, filtered and added sodium chloride and isotope internal standard, and purged 10 min by nitrogen at 40 ℃, desorpbed 2 min at 200 ℃. The purging flow was 40 mL/min. Chromatographic column：DB-624, inlet temperature 270 ℃, split ratio 20：1, high purity He as carrier gas, flow rate 3. 8 mL/min. Temperature programmed condition： 35 ℃ （ 5 min ） , 6 ℃/min to 120 ℃, 20 ℃/min to 210 ℃. AUX temperature was 280 ℃. Mass spectrometric conditions were as follows： ion source temperature 230 ℃, quadrupole temperature 150℃, electrical energy 70 eV. Qualitative analysis was carried out by retention time and mass spectrometric scan in the mass range of 45-450 and quantified by select ion monitoring method. The accuracy and precision were determined by matrix spike. The results showed that ethyl thiol, dimethyl sulfide and dimethyl disulfide had good linear at range of 0. 6-21. 3 μg/L. The limits of detection were 0. 09, 0. 13 and 0. 10 μg/L, respectively. The recovery of high and low spike concentration in 5 kinds of water samples were 90 . 7%-118 . 0% with the RSDs of 2 . 7%-9 . 8%. The method could be used for the analysis of surface water, groundwater and drinking water containing sulfide by using isotope internal standard with good accuracy, stability and practicability.

关 键 词：稳定性同位素内标 吹扫捕集 气相色谱-质谱联用 硫化物 

分 类 号：X832[环境科学与工程—环境工程] O657.63[理学—分析化学]