Instituto de Química, Universidade de São Paulo, C.P. 26077, 05513-970 São Paulo, SP, Brazil.
Instituto de Química, Universidade de São Paulo, C.P. 26077, 05513-970 São Paulo, SP, Brazil.
Talanta. 2015 Jan;131:528-34. doi: 10.1016/j.talanta.2014.08.020. Epub 2014 Aug 19.
This paper describes the development of reversed phase sequential injection chromatography (SIC) methods for separation of simazine (SIM) and atrazine (AT), as well as their metabolites deethylatrazine (DEA), deisopropylatrazine (DIA) and hydroxyatrazine (HAT) exploiting silica based monolithic (50 × 4.6 mm) and core-shell (30 × 4.6 mm, 2.7 µm particles) columns. The separation was made by stepwise elution with two mobile phases: MP1 composed of 15:85 (v/v) acetonitrile: 2.5 mmol L(-1) acetic acid/ammonium acetate buffer (pH 4.2), and MP2, composed of 35:65 (v/v) acetonitrile: 2.5 mmol L(-1) acetic acid/ammonium acetate buffer (pH 4.2).The less hydrophobic compounds (DIA, HAT and DEA) eluted with MP1, whereas SIM and AT eluted with MP2. The method using core-shell column exhibited better chromatographic efficiency compared with monolithic column for separation of SIM and AT, but failed to provide base line separation of DIA and HAT. The proposed composition of mobile phases enabled the monolithic column to separate all the studied compounds with resolution >2.3 at flow rate of 35 µL s(-1) and sampling throughput of 8 analyses per hour, whereas in the core-shell the maximum flow rate allowed in the SIC system was 8 µL s(-1) (sampling throughput of 3 analyses per hour). The limits of detection were between 24 µg L(-1) (AT) and 40 µg L(-1) (DEA) using the monolithic column, and between 20 µg L(-1) (SIM) and 38 µg L(-1) (DEA) with the core-shell. Ultrasound-assisted extraction (80:20 v/v acetonitrile:water) of a soil sample enriched with the five triazines (250, 500 and 1000 µg kg(-1)) resulted recoveries between 51% and 121% of the spiked concentrations.
本文描述了反相顺序注射色谱（SIC）方法的发展，用于分离西玛津（SIM）和莠去津（AT），以及它们的代谢物去乙基莠去津（DEA）、去异丙基莠去津（DIA）和羟基莠去津（HAT），利用基于硅胶的整体式（50×4.6mm）和核壳式（30×4.6mm，2.7µm 颗粒）柱。分离是通过两步洗脱用两种流动相进行的：MP1 由 15:85（v/v）乙腈：2.5mmol L(-1) 乙酸/乙酸铵缓冲液（pH4.2）组成，MP2 由 35:65（v/v）乙腈：2.5mmol L(-1) 乙酸/乙酸铵缓冲液（pH4.2）组成。疏水性较低的化合物（DIA、HAT 和 DEA）用 MP1 洗脱，而 SIM 和 AT 用 MP2 洗脱。与整体柱相比，核壳柱用于 SIM 和 AT 的分离，显示出更好的色谱效率，但未能提供 DIA 和 HAT 的基线分离。流动相的组成使得整体柱能够以 35µL s(-1) 的流速和 8 次/小时的采样通量分离所有研究的化合物，分辨率>2.3，而在核壳柱中，SIC 系统允许的最大流速为 8µL s(-1)（3 次/小时的采样通量）。使用整体柱时，检测限在 24µg L(-1)（AT）至 40µg L(-1)（DEA）之间，而使用核壳柱时，检测限在 20µg L(-1)（SIM）至 38µg L(-1)（DEA）之间。超声辅助提取（80:20v/v 乙腈：水）富集了五种三嗪（250、500 和 1000µg kg(-1)）的土壤样品，回收率为添加浓度的 51%至 121%。
