计算机拟合技术研究C18柱在富集PAEs时的萃取条件

利用固相萃取技术富集了水中5种邻苯二甲酸酯类(邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二(2-乙基己基)酯(DEHP)、邻苯二甲酸二辛酯(DOP)).借助均匀设计法及计算机回归建模优化技术对5种PAEs的固相萃取条件进行了设计与优化,得到最佳固相萃取条件为: 洗脱剂配比: V(正己烷)∶V(丙酮)=30∶1,洗脱体积2 mL,洗脱流速为4 mL/min,上样流速8 mL/min.富集后的样品用带电子捕获检测器的毛细管气相色谱检测,方法的线性范围为1～1000 μg/L (DMP,DEP,DOP),0.2～100 μg/L (DBP,DEHP);线性回归方程的相关系数为0.9970～1.000,检出限为0.02～0.4 μg/L,方法回收率为69%～117%,相对标准偏差为2.2%～9.5%.     

多壁碳纳米管表面邻苯二甲酸二(2-乙基)己酯印迹聚合物的制备及其在固相萃取中的应用

以苯基修饰的多壁碳纳米管为载体,邻苯二甲酸二(2-乙基)己酯为模板分子,甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,在碳纳米管表面接枝一层塑化剂邻苯二甲酸二(2-乙基)己酯印迹聚合层.采用红外光谱和扫描电镜对聚合物进行表征和分析.结果表明,在碳纳米管表面成功接枝一层20～30 nm厚的印迹聚合层.采用高效液相色谱研究该印迹聚合物的吸附性能,结果表明,碳纳米管分子印迹聚合物对邻苯二甲酸二(2-乙基)己酯最大吸附量为69.1 μmol/g,达到吸附平衡时间约为60 min.选择性吸附实验表明,与其它结构类似物相比,该印迹复合材料对邻苯二甲酸二(2-乙基)己酯有良好的识别能力.作为固相萃取材料装填于固相萃取柱中,该印迹聚合物能对芒果汁样品中塑化剂进行有效的分离和富集.     

固相萃取-气相色谱-质谱法分析尿液中邻苯二甲酸单酯和双酯

建立了固相萃取-气相色谱-质谱测定尿液中邻苯二甲酸单酯和双酯的分析方法。尿液经 β-葡萄糖苷酸酶酶解后进行固相萃取净化,用乙腈、乙酸乙酯和乙醚-正己烷(1: 19, v/v)分别洗脱,合并洗脱液,氮气吹干后,用N,O-双三甲基硅基三氟乙酰胺(BSTFA)对邻苯二甲酸单酯进行硅烷化处理,使用气相色谱-质谱法检测。邻苯二甲酸单酯和双酯的线性范围为5~1000 μ g/L,检出限为0.3~1.1 μ g/L,回收率为77.9%~97.7%,相对标准偏差为3.7%~10.9%。应用该方法对50份尿液进行检测,检出邻苯二甲酸二(2-乙基己基)酯(DEHP)等7种邻苯二甲酸单酯和双酯类物质,平均质量浓度为6.0~142.7 μ g/L。该方法准确、可靠、灵敏度高,适用于尿液中邻苯二甲酸单酯和双酯的同时测定。     

固相萃取-超高效液相色谱/串联质谱法检测人体血清中邻苯二甲酸二(2-乙基已基)酯代谢物

建立了固相萃取-超高效液相色谱/串联质谱法检测人体血清中邻苯二甲酸二(2-乙基已基)酯(DEHP)代谢物.血清样品中加入乙酸钠溶液及内标13C4邻苯二甲酸单乙基已基酯(13C4MEHP)后,在37℃条件下用β-葡萄糖醛苷酶酶解提取12h,提取液经MAX固相萃取小柱净化并浓缩到纯水中.以甲醇5 mmol/L乙酸铵溶液为流动相,经Waters UPLC(R)HSS T3色谱柱分离后,在电喷雾离子源负离子模式下,以多反应监测(MRM)方式进行扫描,内标法定量.DEHP代谢物在1.0～100.0 μg/L范围内线性关系良好,检出限均为0.1 μg/kg,回收率89.6％～103.2％.该方法灵敏度高,准确度好,可作为监测人群内暴露的重要技术支撑.     

溶胶-凝胶富勒烯固相微萃取-气相色谱法测定塑料水浸泡液中多种邻苯二甲酸二酯

利用新型溶胶-凝胶富勒烯涂层,结合顶空固相微萃取-气相色谱法-FID检测,对PVC塑料制品在水溶液浸泡液中的12种邻苯二甲酸二酯进行了分析和测定,其检出限为0.097～3.646 μg/L;回收率为87.9%～107%;RSD<8%.对12种邻苯二甲酸二酯类增塑剂的固相微萃取条件和色谱条件进行了优化,并与商用固相微萃取聚二甲基硅氧烷(PDMS)探头的性能进行了比较.本方法应用于PVC玩具及PVC餐垫样品的分析,结果令人满意.     

模拟唾液浸泡塑料玩具溶出的邻苯二甲酸二(乙基己基)酯的固相微萃取-气相色谱法测定

利用新型溶胶 -凝胶富勒烯C60 涂渍的萃取头 ,采用顶空固相微萃取 -气相色谱法 ,研究了用模拟唾液浸泡塑料玩具溶出的邻苯二甲酸二(乙基己基)酯(DEHP)的固相微萃取(SPME)条件 ,并对聚氯乙烯玩具制品的模拟唾液浸泡液中增塑剂进行了分析和测定 ,方法的检出限为1.02μg/L ,实际样品的检出限为10.2×10-6(w) ,相对标准偏差RSD=10.5 %(n=7)。     

快速溶剂萃取-高效液相色谱测定塑料中邻苯二甲酸酯类化合物

反相高效液相色谱;快速溶剂萃取;邻苯二甲酸二(乙基)己基酯;邻苯二甲酸二正辛酯     

固相萃取-气相色谱法测定纺织品中的邻苯二甲酸酯类环境激素

采用索氏提取法以正己烷为提取溶剂提取纺织品中的邻苯二甲酸酯类物质(PAEs),以强阴离子交换固相萃取(SPE)小柱净化本底杂质并富集待测物,建立了纺织品中10余种PAEs环境激素的同时测定方法。采用的固相萃取条件为:5 mL正己烷活化、3 mL异辛烷淋洗、2 mL含15%乙酸乙酯的正己烷溶液洗脱。SPE能有效地对提取液进行富集浓缩,同时对纺织物提取液中的杂质净化效果突出。该方法准确可靠,重现性好,在5~100 mg/kg 添加水平,PAEs各化合物的回收率为86.3%~102.7%,相对标准偏差（RSD）一般小于5%。检测的10余种PAEs中邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二丙酯(DPrP)、邻苯二甲酸二丁酯(DBP)、邻苯二甲酸二戊酯(DAP)、邻苯二甲酸丁基苄基酯(BBP)、邻苯二甲酸二环己酯(DCHP)、邻苯二甲酸二(2-乙基己基)酯(DEHP)、邻苯二甲酸二正辛酯(DNOP)的方法检出限小于1mg/kg,邻苯二甲酸二异壬酯(DINP)与邻苯二甲酸二异癸酯(DIDP）的方法检出限分别为1.74 mg/kg和1.55 mg/kg。     

固相微萃取气相色谱法测定水相中邻苯二甲酸二酯

采用m(聚硅氧烷 (OV 1) )∶m (富勒烯聚二甲基硅氧烷 (PSO C60 ) ) =4∶1的混合固定相自制萃取头 ,利用顶空固相微萃取与气相色谱联用技术 (HS SPME GC)分析了水中 5种邻苯二甲酸二酯。考察了萃取温度、离子强度、吸附和热解吸时间等因素对该方法灵敏度的影响。结果表明该萃取头萃取选择性优于商用PDMS萃取头。方法的检出限为 0 331ng/L～ 12 5 μg/L ;除邻苯二甲酸二正壬酯外 ,相对标准偏差均在 12 %以下     

微溶剂萃取-气相色谱-质谱法测定水中邻苯二甲酸二(2-乙基己基)酯

取水样25mL,加入无水硫酸钠3.0g,加入环己烷2.0mL,振荡萃取3min。移取萃取了邻苯二甲酸二(2-乙基己基)酯(DEHP)的上层有机相2.0μL注入HP-5毛细管柱(30m×0.32mm,0.25μm)色谱分离后进行质谱测定。DEHP的质量浓度在50.0μg.L-1以内与其峰面积呈线性关系,方法的检出限(3S/N)为0.052μg.L-1。分析了早、中、晚不同时间的天津市自来水,并用标准加入法做回收试验,测得回收率在97.0%～109.4%之间,测定值的相对标准偏差(n=6)均小于2.5%。     

Development of a time-resolved fluoroimmunoassay for phthalate esters in water

Summary An antigenic derivative of dimethylphthalate has been synthesized and used to raise an antibody that selectively recognizes o-phthalate esters. With this antibody we have standardized a direct time-resolved fluoroimmunoassay for these esters in water. Its sensitivity is 0.5 pmol/ml.     

Synthesis and Structural Characterization of Co( Ⅱ ) Coordination Polymer [Co(μ-phth)(imi)2]n

A new cobalt( Ⅱ ) complex [Co(μ-phth)(imi)2]n (phth = o-phthalato, imi = imidazole)has been synthesized by the reaction of CoCl2 with disodium o-phthalate and imidazole. The crystal structure of the compound has been determined by single-crystal X-ray diffraction. The crystal is of monoclinic system, space group Pn with a = 8.405(1), b = 9.995(1), c = 9.996(2) (A),β= 104.479(2),V= 813.0(2) (A)3, Dc= 1.467 g/cm3, C14H12N4O4Co, Mr= 359.21, F(000) = 366,μ = 1.079 mm-1, Z = 2, R = 0.0483 and wR = 0.1209 for 1583 observed reflections (Ⅰ＞ 2σ(Ⅰ)). In the title complex, the Co(Ⅱ) ions are bridged by o-phthalate ligands in a bidentate mode, producing a zigzag infinite chain structure. Each four-coordinated cobalt( Ⅱ ) center was coordinated by two oxygen atoms and two nitrogen atoms to give a distorted tetrahedral geometry. The chains are linked by hydrogen bonds between oxygen atoms belonging to carboxylate groups and hydrogen atoms of imidazole molecules, forming an unusual two-dimensional coordination polymer.     

Synthesis and Structural Characterization of Co(Ⅱ) Coordination Polymer [Co(-phth)(imi_)2]_n

1 INTRODUCTION The polymeric metal complexes with extended structures are of great interest because of their useful chemical or physical properties[1]. Due to the noticeable fact that the aromatic polycarboxylate can provide versatile coordination mode and the non-coplanar structure of the carboxylate groups and the benzene rings, a lot of efforts in this field have been particularly directed to the preparation of aromatic polycarboxylate (such as phthalate, tere- phthalate and isophthal…     

Thiourea-based molecular clips for fluorescent discrimination of isomeric dicarboxylates

A new clip-like receptor, which comprises two thiourea-based binding groups and two naphthalene units, has been designed and synthesized as a fluorescent chemosensor for distinguishing o-phthalate from two other isomers of dicarboxylates. Upon the addition of these three ions, the emission intensity at 420 nm (excitation at 340 nm) decreases drastically through PET. When excited at 380 nm, a new emission band at 460 nm appears and develops gradually upon the addition of the o-phthalate ion and the fluorescent intensity increases markedly over time, but the presence of m-phthalate or p-phthalate do not cause this kind of change. It suggests a guest-induced "off-on" conformational switching signaling transduction. The presence of the o-phthalate anion induces a special conformation with two naphthalene units positioned close enough to exhibit a new emission.     

反相高效液相色谱法测定高能发射药中5种组分

提出了反相高效液相色谱法测定高能发射药中5种组分硝化甘油(NG)、黑索今(RDX)、硝基胍(NQ)、Ⅱ号中定剂(C2)和邻苯二甲酸二正辛酯(DOP)的含量。试样溶解后进行色谱分离,采用Agilent色谱柱(150mm×4.6mm,5μm),流动相为甲醇-水(60+40)混合溶液(用于分离NG、RDX、NQ和C2)和甲醇-水(95+5)混合溶液(用于分离DOP),在波长220nm处进行测定。NG的质量浓度在0.42～4.08g.L-1,RDX在1.41～5.04g.L-1,NQ在1.11～3.74g.L-1,C2在0.07～0.90g.L-1,DOP在0.08～0.37g.L-1时分别与其峰面积呈线性关系。5种化合物的加标回收率在99.3%～101.9%之间;相对标准偏差(n=6)在0.19%～3.1%之间。     

Organophosphate esters by GC–MS: An optimized method for aquatic risk assessment

Organophosphate esters used as flame retardants and plasticizers are ubiquitous contaminants in surface waters. Many studies indicate that these compounds are neurotoxicants, endocrine disruptors, and may affect reproduction and development of aquatic organisms. Thus, analytical methods that allow accurate quantification of these contaminants at environmentally relevant concentrations are desirable for risk assessment studies. In this study, a method based on solid phase extraction and gas chromatography coupled to mass spectrometry was developed for determination of organophosphate esters in river water extracts. Multivariate optimization was used to determine the best conditions for injection of larger volumes of sample in a Programmable Temperature Vaporization inlet. Furthermore, the matrix effect on the instrumental response was evaluated and compensated by association of extraction‐blank‐matched calibration and isotopically labeled focus standards. The method quantification limits ranged from 0.009 to 0.11 µg/L, staying below the predicted non‐effect concentration for the aquatic compartment for all analytes, which is a requisite for using in risk assessment studies. The method was applied to freshwater samples collected in rivers from the Sao Paulo State, Brazil, and eight out of the ten target organophosphate esters were quantified, being tris(2‐chloroisopropyl) phosphate and tris(phenyl) phosphate the most frequently detected compounds.     

液相色谱串联质谱法研究小刺猴头菌子实体中污染物增塑剂

采用GC/MS和LC-MS/MS联用技术对栽培小刺猴头菌子实体中分离得到的组分A进行分析, 检测出邻苯二甲酸二正辛酯(DNOP)和邻苯二甲酸二丁酯(DBP)两种增塑剂, 建立了对有可能造成栽培食用菌被污染的9种常见增塑剂的同时检测方法, 该方法的回收率为71.6%~82.2%, 精密度为2.11%~8.53%, 检测限为0.002~0.030 μg/L     

Challenges encountered in the analysis of phthalate esters in foodstuffs and other biological matrices

Phthalate esters are ubiquitous environmental pollutants and are recognized as environmental endocrine disruptors because of their potential to elicit reproductive and developmental toxicity. Several phthalate esters have been listed by the US Environmental Protection Agency (EPA) as chemicals of concern. Determination of concentrations of phthalate esters in foodstuffs, typically present at sub to low nanogram-per-gram concentrations (between 0.1 and 100?ng?g^?1), is essential for assessment of human dietary exposure. However, phthalate esters are commonly present as contaminants in several laboratory products, including organic solvents, that are used in sample preparation and analysis. Therefore, accurate analysis of phthalates in food samples is a challenging task. In this review, we summarize the methods available for the determination of phthalate esters in foodstuffs and report on concentrations of phthalates in foodstuffs and potential sources of contamination by phthalates in the analysis of foodstuffs. We offer suggestions to eliminate and/or reduce background levels of contamination by phthalates in the analysis of food and other biological samples. We also introduce methods that are suitable for trace analysis of phthalates in a variety of liquid and solid food samples, in particular, a liquid–liquid extraction method for removal of lipids from food samples, because these can substantially reduce background levels of phthalates in the analytical procedure.     

Synthesis and Structural Characterization of Gd(Ⅱ) Coordination Polymer [Gd2(μ-phth)3(b-pd)(H2O)5]n

A new Gd(Ⅱ) complex [Gd2(μ-phth)3(b-pd)(H2O)5]n (phth = o-phthalato, b-pd = N,N- bipyridine) has been synthesized by the reaction of GdO2 with o-phthalate, H2O and 2,2′-bipyridine. The crystal structure has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group P with a = 11.82920(10), b = 13.53550(10), c = 13.7381(2)(A), α = 88.99, β = 66.9120(10), γ = 66.2370(10)°, V = 1826.02(3)(A)3, Dc = 1.915 g/cm3, C34H30N2O17Gd2, Mr = 1053.10, F(000) = 1024, μ = 3.680 mm-1, Z = 2, R = 0.0612 and wR = 0.1320 for 6259 observed reflections (I > 2σ(I)). In the title complex, the Gd(II) ions are bridged by o-phthalate ligands in a bidentate mode, producing a 1D infi- nite chain structure. Each eight-coordinated Gd(Ⅱ) center is coordinated by eight oxygen atoms from phth to give a distorted dodecahedral geometry, and each nine-coordinated Gd(Ⅱ) center is coordi- nated by two N atoms from b-pd and seven oxygen atoms from phth to give a distorted geometry of capped square antiprism. The chains are linked by π-π interactions and hydrogen bonds between oxy- gen atoms of carboxylate groups and H2O molecules and hydrogen atoms of H2O, b-pd and o-phth molecules, forming an unusual three-dimensional coordination polymer.     

Capillary electrochromatographic analysis of aliphatic mono- and polycarboxylic acids

The parameters influencing the electrochromatographic separation of aliphatic organic acids in a capillary column with a wall-coated macrocyclic polyamine have been studied. Indirect detection using chromate, pyromellitate, trimellitate, o-phthalate, benzoate and acetate as background electrolytes has been tested. A complete separation of polyprotic acids could be achieved with pyromellitate buffer (7.5 mM, pH 6.5), and satisfactory results for the simultaneous separation of monoprotic acids and polyprotic acids were found using a capillary column of 70 cm (50 cm effective length)x75 microm inner diameter, electrokinetic injection (-10 kV, 10 s), benzoate buffer (6 mM, pH 4.6), separation voltage of -10 kV, and detection at 220 nm. For the separation of the geometric isomers fumarate and maleate, acetate buffer was found the best choice among the background electrolytes tested. The method so established has been applied to the determination of organic acids in soy sauce, brandy, lemon juice, spinach juice and cigarette. From the retention behavior, it was found that the separation mechanism on the bonded phase was influenced by the macrocyclic effect, electrostatic attraction, hydrogen bonding, van der Waals forces, and anion exchange, in addition to the differences in electrophoretic mobility.