HPLC-MS-MS法测定水体中残留的氨基甲酸酯类农药

应用高效液相色谱-串联质谱(HPLC-MS-MS)联用技术,建立了检测水体中氨基甲酸酯类农药残留的方法。水样经氨基柱固相萃取,二氯甲烷洗脱,梯度流动相洗脱,电喷雾正离子(ESI+)模式采集、选择反应性监测模式(SRM)对定性、定量离子进行MS/MS测定。5种氨基甲酸酯类农药在5～200ng/L范围内线性关系良好,回收率为80%～92%,相对标准偏差均小于10%,方法检出限分别为:异丙威和仲丁威为1.4ng/L,克百威和甲萘威为1.5ng/L,恶虫威为1.6ng/L。该方法适用于水体中氨基甲酸酯类农药残留的检测。     

市售虾中磺胺甲噁唑的LC-MS-MS定量分析

当前各国对食品安全都极为重视,我国以及发达国家相继制定了相关兽药用量的法规和标准,尽管中国已经加入到了WTO,但我国的畜禽产品出口还是遇到了很多困难,农药、兽药、饲料添加剂等非法滥用,造成药物残留而直接影响到人类的健康。如引发癌症,婴儿畸形,代谢紊乱以及抗药性等诸多问题。其中磺胺类兽药是一类受到严格限制使用的兽药,本文研究了市售虾中磺胺甲(口恶)唑定量分析方法,检出限绝对量可达到0.5pg,完全满足发达国家的最低检出规定的苛刻标准。     

A liquid chromatography tandem mass spectrometry method for simultaneous analysis of 46 atmospheric particulate-phase persistent organic pollutants and comparison with gas chromatography/mass spectrometry

A novel multi-analyte method for the simultaneous determination of 46 compounds of environmental concern, most of them belonging to the category of persistent organic pollutants, was developed using high-performance liquid chromatography and the results were compared to those obtained by gas chromatography. This study was performed in perspective of a cumulative exposure assessment of substances of health concern in environments where high levels, relatively to airborne particulate matter, can be found. The target compounds included polychlorinated biphenyls, brominated flame–retardants and derivatives of polycyclic aromatic hydrocarbons.

The multi-analyte method was evaluated in air particulate matter in terms of reproducibility, linearity, recovery, limits of detection and quantification and matrix effect. The recovery was above 70% for all the analytes, whereas limits of quantification ranged between 23 and 390 pg?m^?3 in liquid chromatography and less than ten times in gas chromatography–mass spectrometry.

Matrix effect was generally negligible for both the techniques, except the case of the detection of oxygenated derivatives of polycyclic aromatic hydrocarbons by gas chromatography.

In order to demonstrate the efficacy and to assess the method performances (accuracy and precision), both the techniques were applied to standard reference materials, and the results were compared, discussing their advantages and disadvantages.

The method was finally applied to a real sample of indoor airborne particulate matter with aerodynamic diameter ≤4 μm (PM₄).

We demonstrated that liquid chromatography was the only technique able to analyse the 46 compounds, including thermally degradable ones, with a single chromatographic run without derivatisation steps. On the other hand, gas chromatography still presents higher sensitivity for the detection of some of the investigated compounds. This study can be considered only explorative and further improvements can be expected with new-generation LC-MS instruments (10–100 times more sensitive).     

Multi-residue analysis of traces of pesticides and antibiotics in honey by HPLC-MS-MS

The aim of this work was to develop an analytical method for simultaneous assay of residues of two families of antibiotics, and three pesticides, in honey. The assays involved a mixture of five tetracyclines, four sulfamides, and the pesticides coumaphos, carbendazim, and amitraz (two metabolites). All the compounds were extracted from honey and pre-concentrated by optimised solid-phase extraction (SPE). Analysis was by high-performance liquid chromatography-mass spectrometry-mass spectrometry (HPLC-MS-MS) using a triple-quadrupole spectrometer in multiple reaction monitoring (MRM) mode in order to identify and quantify the compounds present (Sheth et al J Agric Food Chem 38:1125–1130, 1990). During development of the analytical method a strong matrix effect was found that depended on the floral origin of the honey. This led to the development of a standard additions method to quantify the contaminants sought.     

New Au(III), Pt(II) and Pd(II) complexes with glycyl-containing homopeptides

Twelve new Au(III), Pt(II) and Pd(II) complexes with glycyl-containing homopeptides glycyl-glycine (G2), glycyl-glycyl-glycine (G3), glycyl-glycyl-gycyl-glycine (G4), glycyl-glycyl-glycyl-glycyl-glycine (G5) and glycyl-glycyl-glycyl-glycyl-glycyl-glycine (G6) have been synthesized, isolated and characterized spectroscopically and structurally by means of solid-state linear-dichroic infrared (IR-LD) spectroscopy of oriented colloids in nematic liquid crystal host, ¹H- and ¹³C-NMR, TGA and DSC, UV–Vis spectroscopy, EPR, ESI- and FAB mass spectrometry and HPLC tandem mass spectrometry (HPLC-MS/MS). Quantum chemical calculations are carried out with a view to obtain the structures and spectroscopic properties of the ligand and newly synthesized metal complexes.