高效液相色谱-电喷雾质谱联用研究三氯生的光聚合产物

三氯生在光解时可能会产生二噁英类物质,因而它在日用化学品中的安全性受到学术界的广泛关注.本文采用高效液相色谱-电喷雾质谱研究了三氯生在紫外光照射下的光聚合反应,通过对产物的准分子离子分析,初步确定了7种光聚合产物.聚合物的分子离子分别为505、540、792,且有同分异构体存在,其异构体个数分别为2个、3个和2个.这些物质的产生主要由三氯生分子间脱除氯化氢、分子上脱除氯离子等过程来聚合完成.在光解溶液中也测到2,8-二氯代二苯并-对-二噁英,该物质则是通过分子自身脱除氯化氢而环化产生.同时应用液相色谱定性分析了不同光源对光聚物产生及含量变化的影响.结果表明,三氯生的光聚合反应受光源的影响显著,UVB比UVA更易产生聚合反应.     

固相萃取-超高效液相色谱-串联质谱法测定人指甲中的三氯生和三氯卡班

建立了人指甲中三氯生和三氯卡班的固相萃取结合超高效液相色谱-串联质谱(UPLC-MS/MS)检测方法。指甲样品经氢氧化钠消化,C18柱富集净化后,通过Waters ACQUITY^TM UPLC HSS T3色谱柱(100 mm×2.1 mm, 1.8 μm) 分离,以甲醇和水为流动相进行梯度洗脱,采用三重四极杆串联质谱仪负离子模式进行检测,同位素内标法定量。三氯生和三氯卡班分别在0.5~500.0 μg/kg和0.1~100.0 μg/kg范围内线性关系良好,相关系数(r²)均为0.999,方法定量限分别为2.0 μg/kg和0.2 μg/kg。3个水平的平均加标回收率为95.9%~110.2%,相对标准偏差为0.6%~9.7%(n=6)。本方法具有良好的灵敏度、回收率和重复性,适合指甲中痕量目标污染物的测定。利用该方法分析了60份实际样品,目标物的检出率为100%,三氯生和三氯卡班的含量范围分别为     

Evolution of dispersive liquid–liquid microextraction method

Dispersive liquid–liquid microextraction (DLLME) has become a very popular environmentally benign sample-preparation technique, because it is fast, inexpensive, easy to operate with a high enrichment factor and consumes low volume of organic solvent. DLLME is a modified solvent extraction method in which acceptor-to-donor phase ratio is greatly reduced compared with other methods. In this review, in order to encourage further development of DLLME, its combination with different analytical techniques such as gas chromatography (GC), high-performance liquid chromatography (HPLC), inductively coupled plasma-optical emission spectrometry (ICP-OES) and electrothermal atomic absorption spectrometry (ET AAS) will be discussed. Also, its applications in conjunction with different extraction techniques such as solid-phase extraction (SPE), solidification of floating organic drop (SFO) and supercritical fluid extraction (SFE) are summarized. This review focuses on the extra steps in sample preparation for application of DLLME in different matrixes such as food, biological fluids and solid samples. Further, the recent developments in DLLME are presented. DLLME does have some limitations, which will also be discussed in detail. Finally, an outlook on the future of the technique will be given.     

原位衍生分散液相微萃取-气相色谱/质谱快速检测饮用水中的痕量三氯生

建立了原位衍生分散液相微萃取-气相色谱/质谱检测饮用水中痕量三氯生的方法.将含有30.0 μL氯苯(萃取剂)和50.0 μL乙酸酐(衍生试剂)的0.5 mL丙酮(分散剂)作为萃取体系,快速注入到5.0 mL含有K2CO3(0.5%, m/V)的水溶液中.在5000 r/min下离心2 min后,得到(10±0.5) μL沉积相(氯苯),取底部沉积相1.0 μL进行气相色谱/质谱联用仪分析.方法的线性范围为0.05～50 μg/L(r=0.9994),检出限为0.01 μg/L;相对标准偏差2.0%(n=5).利用本方法检测了饮用水中的三氯生,平均加标回收率分别为92.1%和98.4%,结果满意.     

亲水作用液相色谱-串联质谱测定水产品中的消毒剂残留

首次建立了水产品中消毒剂二氯异氰尿酸和三氯异氰尿酸总残留量以及三氯生残留量的液相色谱-串联质谱(LC-MS/MS)同时测定方法。水产样品用乙腈-5%氨水(体积比30∶70)提取,HyperSep RetainAX SPE固相萃取小柱净化,采用亲水作用色谱柱SeQuant ZIC-HILIC分离,以(0.1%甲酸+10 mmol/L乙酸铵)水溶液-乙腈体系为流动相进行梯度洗脱,在电喷雾负离子模式下以多反应监测(MRM)方式检测。结果表明,在0.042～2.4 mg/L质量浓度范围内线性良好,相关系数大于0.99,在3个不同加标水平下,平均回收率为68%～96%,相对标准偏差(RSD)为5.9%～10.9%,检出限(LOD,S/N=3)和定量下限(LOQ,S/N=10)分别为0.015、0.05 mg/kg。实际样品测定表明,该方法适用于各种水产品中三氯生、二氯异氰尿酸和三氯异氰尿酸消毒剂残留量的测定。     

Molecularly imprinted polymer functionalized magnetic Fe3O4 for the highly selective extraction of triclosan

We present a facile strategy to prepare the molecularly imprinted polymers layer on the surface of Fe₃O₄ nanoparticles with core‐shell structure via sol–gel condensation for recognition and enrichment of triclosan. The Fe₃O₄ nanoparticles were first synthesized by a solvothermal method. Then, template triclosan was self‐assembled with the functional monomer 3‐aminopropyltriethoxysilane on the silica‐coated Fe₃O₄ nanoparticles in the presence of ethanol and water. Finally, the molecularly imprinted polymers were formed on the surface of silica‐coated Fe₃O₄ nanoparticles to obtain the product. The morphology, magnetic susceptibility, adsorption, and recognition property of magnetic molecularly imprinted polymers were characterized using transmission electron microscopy, Fourier transform infrared spectroscopy, X‐ray diffractometry, vibrating sample magnetometry, and re‐binding experiments. The magnetic molecularly imprinted polymers showed binding sites with good accessibility, fast adsorption rate, and high adsorption capacity (218.34 μg/g) to triclosan. The selectivity of magnetic molecularly imprinted polymers was evaluated by the rebinding capability of triclosan and two other structural analogues (phenol and p‐chlorophenol) in a mixed solution and good selectivity with an imprinting factor of 2.46 was obtained. The application of triclosan removal in environmental samples was demonstrated.     

超高效液相色谱法测定湿巾中的三氯羟基二苯醚

采用超高效液相色谱法(UPLC)检测湿巾中的三氯羟基二苯醚含量.湿巾样品加甲醇超声提取,离心过滤后上机,采用甲醇-水(体积比为8∶2)为流动相,Phenomenex C18色谱柱分离,在波长280 nm下检测,外标法定量.结果表明:方法在0.50~100.00 mg/L质量浓度范围内线性良好,相关系数为0.999 1,检出限为0.30 mg/kg,方法定量限为10.0 mg/kg,RSD为2.3%,加标回收率为90.50%~93.50%.方法前处理简便快捷,准确度、精密度、稳定性好,检测结果准确可靠.     

微波辅助萃取/超高效液相色谱-静电场轨道阱高分辨质谱法同时测定纺织品中的抗菌剂和紫外光稳定剂

建立了超高效液相色谱-静电场轨道阱高分辨质谱(UPLC-Orbitrap HRMS)同时测定纺织品中7种抗菌剂和7种紫外光稳定剂含量的分析方法。以甲醇为萃取溶剂,85℃下微波萃取纺织品中的抗菌剂和紫外光稳定剂,萃取液经浓缩定容后进行UPLC/Orbitrap HRMS分析,外标法定量。以甲醇-0.1%甲酸水溶液(含5 mmol/L乙酸铵)为流动相,14种目标化合物在Hypersil GOLD色谱柱(100 mm×2.1 mm,1.9μm)上进行梯度洗脱。一级质谱扫描范围为m/z 100~500,14种目标化合物的质量数准确度误差均小于2×10-6(2ppm),其中对氯间二甲酚(PCMX)和三氯生采用电喷雾负离子模式,其余12种目标化合物均采用电喷雾正离子模式。通过目标化合物的保留时间和准分子离子峰的精确质量数进行定性,提取离子色谱图的峰面积进行定量。在各自的线性范围内,每种目标化合物的提取离子色谱图的峰面积均与其质量浓度线性相关,相关系数均大于0.998。在3个不同的加标浓度水平下,方法的平均加标回收率为80.1%~95.6%,相对标准偏差为2.9%~10.5%。方法的检出限(S/N=3)为0.1~0.3μg/kg。该方法定性可靠,定量准确,检出限低,完全可满足纺织品中抗菌剂和紫外光稳定剂含量检测的需要。     

Photolytic degradation of triclosan in the presence of surfactants

The formation of 2,8-dichlorodibenzo-p-dioxin (2,8-DCDD) in the photolytic degradation of triclosan has evoked a great concern for its safety and environmental fate. The photochemical behaviour of triclosan in daily-used chemical products, in which triclosan is present in relatively high concentrations and coexists with surfactants, was, however, addressed less frequently. The present work is focused on the mechanistic aspects of triclosan photodegradation in an aqueous medium with a relatively high concentration (≥ 30 mg L⁻¹) and on the influence of pH (8.7 and 10.5) and surfactants (Triton X100, SDS, and CTMAB) on this process. The results demonstrated that photodegradation was strongly affected by the pH and the presence of surfactants. Photodegradation products, including 2,4-dichlorophenol (2,4-DCP), 5-chloro-2-(4-chlorophenoxyl)-phenol, 2,8-DCDD, dimers, trimers, and other intermediates, were identified. Based on the analysis of photoproducts, homolytic scission of ether bond, dechlorination, ring closure, and photo-polymerisation were proposed as the main routes of triclosan photodegradation.     

Organo-Montmorillonite as a Controlled Release Reservoir for Triclosan in Silicone Elastomer: A Flow Micro-Calorimetry and Leaching Study

Summary: Organically modified montmorillonite (o-MMT) in a room temperature addition cured silicone elastomer (PDMS) has been found to control the release of 2,4,2′-trichloro-2′-hydroxy diphenylether (triclosan (TCS)) from the composite. The effect of o-MMT gallery polarity on controlled release was investigated via different intercalants and the interaction of triclosan with the o-MMT was investigated using flow micro-calorimetry (FMC). The latter was found not to be a universal predictor of controlled release activity of the composite as combined TCS and PDMS interactions with MMT/o-MMT leading to intercalation (observed using WAXS) and controlled release activity must also be considered. Southern Clay Products Cloisite® 15A (C15A) gave the most sustained release of TCS whilst also featuring a uniform gallery spacing in the composite. A pore structure based on self-assembled C15A intercalant alkyl tails is tentatively proposed.