瓶装饮用水中高氯酸盐含量的离子色谱-电导检测法和离子色谱-串联质谱法测定研究

Study of Perchlorate in Bottled Drinking Water with Ion Chromatography-Conductance Detection and Ion Chromatography-Tandem Mass Spectrometry

建立了离子色谱-电导检测法(IC-CD)和离子色谱-串联质谱法(IC-MS/MS)测定瓶装饮用水中高氯酸盐浓度的方法,并对两种方法进行F检验(精密度)和t检验(系统误差)。结果表明,IC-CD的检出限为0.35μg·L^(-1),定量限为1.17μg·L^(-1),在0.5~8.0μg·L^(-1)范围内呈线性关系(R 2=0.9993),相对标准偏差(RSD)为4.55%(n=7),加标回收率为99.50%~104.81%。IC-MS/MS的检出限为0.01μg·L^(-1),定量限为0.04μg·L^(-1),在0.05~20.00μg·L^(-1)范围内呈线性关系(R 2=0.9998),其RSD为1.21%(n=7),加标回收率为96.40%~102.52%。F检验和t检验表明两种方法在各自的线性范围内,检测方法准确可靠。根据建立的方法对瓶装饮用水中高氯酸盐含量进行测定,结果发现瓶装饮用水中高氯酸盐的浓度均低于美国环境保护署所提出的暂定安全浓度限量值(15.0μg·L^(-1))。

Two methods of ion chromatography-conductance detection(IC-CD)and ion chromatography-tandem mass spectrometry(IC-MS/MS)were established for the determination of perchlorate in bottled drinking water.Meanwhile the F-test(precision)and t-test(systematic error)were carried out for the two methods.The result for IC-CD indicated that the detection limit was 0.35μg·L^(-1)and the quantitation limit was 1.17μg·L^(-1).The correlation coefficient was 0.9993 in the range of 0.5-8.0μg·L^(-1),the relative standard deviation was 4.55%(n=7),and the recovery of the sample was 99.50%-104.81%.For IC-MS/MS,the method was also satisfying with good detection limit(0.01μg·L^(-1)),quantitation limit(0.04μg·L^(-1)),relative standard deviation(1.21%,n=7),perfect correlation coefficient(0.9998)in linear range of 0.05-20.00μg·L^(-1)and the recovery of the sample was 96.40%-102.52%.F-test and t-test showed that the two methods were accurate and reliable in their own linear range.The methods were successfully applied to the determination of perchlorate in real water samples.The results showed the concentration of perchlorate in bottled drinking water was lower than the tentative safe concentration limit(15.0μg·L^(-1))proposed by EPA of United States.