基质固相分散萃取和固相萃取-高效液相色谱-三重四极杆-复合线性离子阱质谱同时测定奶制品中6种雌激素

采用了基质固相分散萃取（MSPD）和固相萃取（SPE）技术分别对奶制品（奶粉和牛奶）中6种雌激素进行提取和净化。结果显示,MSPD适用于固体奶粉的处理,而SPE则适用于液体牛奶的处理。基于优化结果,利用高效液相色谱-三重四极杆-复合线性离子阱质谱（HPLC-Q-TRAP-MS）建立了在不同奶制品中同时测定6种雌激素含量的方法。方法学考察结果显示,建立的分析方法符合含量测定要求,在0.1~200 mg/L（雌三醇为0.1~20 mg/L）范围内线性关系良好（相关系数（R²）>0.99）;检出限（LOD,S/N=3）和定量限（LOQ,S/N=10）分别为0.01~0.05 mg/L和0.05~0.10 mg/L。在添加水平分别为1.0、5.0和10 mg/kg时,固态奶粉经MSPD处理后,6种雌激素的平均回收率为71.8%~106.0%（RSD为1.6%~9.2%,n=3）;液态牛奶经SPE处理后,6种雌激素的平均回收率为70.3%~108.4%（RSD为2.0%~11.0%,n=3）。该方法灵敏度和重复性高,适于分析复杂基质中雌激素的痕量残留。     

量子点标记荧光免疫分析测定雌三醇

采用包被雌三醇完全抗原竞争免疫分析模式,以量子点标记羊抗兔抗体为荧光探针,建立了一种测定雌三醇的量子点标记的荧光免疫分析新方法.方法测定雌三醇的线性范围为0.01～10 000μg/L;检出限为0.007 5μg/L.此法用于尿液样品的分析,并利用高效液相色谱法进行对照,测定结果一致。     

MIL-101(Cr)填充针头式过滤器固相微萃取/高效液相色谱法检测水中雌激素

建立了多孔金属有机骨架MIL－101（Cr）填充针头式尼龙过滤器固相微萃取结合高效液相色谱－荧光检测器对水中雌二醇（E2）、雌三醇（E3）、雌酮（E1）3种雌激素进行快速检测的方法。MIL－101（Cr）与尼龙滤膜对雌激素表现出协同吸附效果。通过对萃取材料以及新型萃取装置制备过程、吸附、洗脱过程进行优化,可对10 mL水样中3种雌激素实现4 min吸附、1 min洗脱的快速前处理。结果显示,E2和E3在0.2～500 μg/L、E1在5～500 μg/L质量浓度范围内线性良好,相关系数（r2）为0.998 2～0.999 3,检出限分别为0.05、0.06、1.50 μg/L,日内和日间相对标准偏差（RSD）分别为0.20%～3.2%（n = 6）和 5.9%～6.1%（n = 3）。水样中3种分析物的加标回收率为84.1%～108%,RSD均不大于5.5%。该方法简单方便、灵敏度高,能够用于水样中3种雌激素的快速筛查和准确定量。     

荧光碳量子点的绿色合成及高灵敏高选择性检测汞离子

本实验以苹果汁为原料,通过一步水热法合成得到了水溶性好及稳定性高的蓝色荧光碳量子点。研究发现Hg2+对碳量子点荧光有良好的猝灭作用,从而建立了一种快速检测Hg2+的新方法。实验发现在pH 7.0磷酸盐缓冲介质中碳量子点荧光猝灭强度与Hg2+浓度在5~100 nmol/L和1~50μmol/L范围内呈线性关系,检出限为2.3 nmol/L(S/N=3)。本方法可用于实际水样中Hg2+的测定。     

荧光法快速测定邻苯二甲酸酯的总量

基于邻苯二甲酸酯在浓硫酸下荧光增强的原理构建了一种测定邻苯二甲酸酯总量的荧光分析新方法。 体系的荧光强度与邻苯二甲酸酯的浓度在5.00~600 μg/L的范围内呈线性关系,方法的检出限为0.57 μg/L,回收率在91.6%~105.1%之间。 该方法简单、快速、灵敏度高、线性范围宽。 用于塑料水杯和聚氯乙烯水管中邻苯二甲酸酯总量的测定,结果令人满意。     

新型衍生化试剂雌激素衍生物的大气压化学电离质谱增敏研究

合成了用于酚羟基化合物衍生化试剂10-乙基吖啶酮-2-磺酰氯(EASC),EASC与雌二醇和雌三醇, 在pH=10.5 的NaHCO3缓冲溶液中、60 ℃下反应3 min可获得稳定的衍生产物. EASC与丹磺酰氯(Dansyl-Cl)相比:最大摩尔吸光系数之比UVEASC/UVDansyl-Cl = 6.67;荧光量子效率之比Φf(EASC)/Φf(Dansyl-Cl)=43,对雌二醇和雌三醇标记后的质谱离子流强度比为:ICEASC/ICDansyl-Cl = 4.98(雌二醇) 和 ICEASC/ICDansyl-Cl = 4.51(雌三醇).在LC-MS-APCI (MRM)模式下,能够高灵敏地实现雌二醇和雌三醇的快速质谱测定.建立的方法具有良好的重现性,回归系数大于0.9995;检出限分别为4.3 ng/L(雌二醇)和14 ng/L(雌三醇).对实际样品中藏羚羊粪便、根田鼠尿样和狼血清中痕量游离的雌二醇和雌三醇进行了测定,结果满意.     

用亲水性的C16硅胶反相色谱柱分离测定血清样品中的雌激素

将亲水性较强的C16硅胶反相色谱柱应用于血清样品中β-雌二醇、雌三醇、雌酮和17α-乙炔基雌二醇的分离。实验对分离条件进行了优化,得到的最佳色谱条件是：柱温40℃,流速1mL／min,以40％乙腈水溶液作等度洗脱。在此条件下．4种雌激素可在大约26min内实现基线分离,得到的4个色谱峰峰型对称。分离后的4种雌激素用紫外检测器在200nm处进行测定,方法对β-雌二醇、雌三醇、雌酮和17α-乙炔基雌二醇的检出限分别为0．024、0．015、0．012和0．016mg/L;校正曲线的线性范围为2-3个数量级,相关系数为0．998以上。方法应用于血清样品的测定,β-雌二醇、雌三醇、雌酮和17α-乙炔基雌二醇的标准加入回收率分别为96．3％、103．7％、100．1％和95．2％。     

固相萃取-超高效液相色谱-三重四极杆质谱法同时测定不同水体中的6种雌激素

建立了固相萃取-超高效液相色谱-三重四极杆质谱（SPE-UPLC-MS/MS）联用技术同时测定不同水体中6种雌激素（雌三醇、17-β-雌二醇、17- α-雌二醇、雌酮、炔雌醇、己烯雌酚）的分析方法。样品经HLB固相萃取柱提取和净化后经BEH C18色谱柱分离,采用MS/MS多反应监测模式（MRM）进行分析。采用内标法定量,以雌三醇-D3、17-β-雌二醇-D2、己烯雌酚-D8为内标。当6种雌激素的质量浓度在1.0~100 μg/L线性范围内时,所得回归方程的相关系数（r）均不小于0.9982;方法检出限为0.27~0.45 ng/L,定量限为1.08~1.78 ng/L;在高、中、低3个添加水平下的回收率为68.3%~97.4%,相对标准偏差（RSD）小于15%。该方法灵敏、准确,检测范围广,分析速度快,适用于地表水、废水、饮用水源水及生活用水等不同水体中6种雌激素的同时检测。     

固相萃取-高效液相色谱荧光检测法测定人血浆3-硝基酪氨酸含量

建立了人血浆中痕量3-硝基酪氨酸的高效液相色谱-荧光检测法. 血浆经乙腈沉淀蛋白后,上清液用氮气吹干,残渣复溶后过C18固相萃取小柱净化浓缩,洗脱液再用氮气吹干,残渣进行荧光衍生化反应.采用高效液相色谱分离,荧光检测器检测,外标法定量.3-硝基酪氨酸在0.50～50.0 nmol/L范围内线性关系良好,相关系数为0.9999;样品加标绝对回收率为89.3%～91.9%,相对回收率为99.2%～107.9%;日内相对标准偏差为1.46%～4.79%,日间相对标准偏差为2.75%～9.20%;在血浆中检出限为0.25 nmol/L;测定正常人血浆中3-硝基酪氨酸平均浓度为118 nmol/L(n=21),Ⅱ型糖尿病病人血浆中3-NT平均浓度为3.63 nmol/L(n=23).本方法灵敏度高,重现性好,适用于临床研究中大样本量的测定.     

气相色谱-质谱法同时测定饲料中6种雌激素类药物

建立了固相萃取/气相色谱-质谱法(GC-MS)同时测定饲料中己烷雌酚、己烯雌酚、双烯雌酚、雌酮、17β-雌二醇、雌三醇的检测方法。饲料样品经乙醚提取后,HLB固相萃取柱净化、衍生化后用气相色谱-质谱仪进行检测,外标法定量。结果表明,己烷雌酚在2.5~250 ng/m L,其它5种雌激素类药物在5~500ng/m L范围内具有良好的线性关系,相关系数不小于0.99,检出限为3~8μg/kg,样品的平均加标回收率为75.9%~96.3%。该方法检出限低,能够准确进行定性和定量测定,可同时测定饲料中的6种雌激素类药物。     

A systematic investigation to optimize simultaneous extraction and liquid chromatography tandem mass spectrometry analysis of estrogens and their conjugated metabolites in milk

In this study, the simultaneous extraction of estrone (E1), 17β-estradiol (E2), estriol (E3), ethinylestradiol (EE2), and their glucuronated and sulfated metabolites in milk was optimized using solid-phase extraction (SPE). The aim of this research was to analyze estrogens and their conjugated metabolites by liquid chromatography with tandem mass spectrometry (LC–MS/MS) in a single run, without the need to perform enzymatic cleavage and derivatization. Two SPE cartridges in tandem were used, consisting of sorbents based on the hydrophilic–lipophilic balance and amine-functionalized packing materials. To monitor analyte loss at every step of the SPE procedure ¹⁴C-labeled E2 was spiked into the milk sample and the radioactivity was monitored at all stages of the SPE. In addition, non-radiolabeled standards of estrogens and metabolites were used to optimize solvent systems for the SPE and LC–MS/MS. The optimized method described in this paper can achieve recoveries ranging from 72% to 117% for the free estrogens (E1, E2, E3, and EE2), and 62% to 112% for seven conjugated metabolites. The three doubly conjugated, highly polar metabolites included in this study gave lower recoveries (≤43%) due to poor retention in SPE. Finally, commercial milk samples were analyzed for the presence of estrogens and their conjugated metabolites. Estrone (concentration range: 23–67 ng/L) was found to be the major free estrogen present in all milk samples. Estradiol was consistently observed in milk, but the concentrations were below the limit of detection (LOD of 10 ng/L), and no estriol and ethinylestradiol were detected. Several conjugated estrogen metabolites were identified, 17β-estradiol-3-glucuronide (71–289 ng/L), estrone-3-sulfate (60–240 ng/L), 17β-estradiol-3,17β-sulfate (<LOD to 30 ng/L), and estrone-3-glucuronide (<LOQ of 25 ng/L). This method proved efficient in the simultaneous analysis of estrogens and their metabolites in milk.     

表面增强拉曼光谱法同时检测奶粉中三聚氰胺和二聚氰胺

本文建立了奶粉中同时检测三聚氰胺及二聚氰胺的表面增强拉曼光谱法.奶粉样品经15％三氯乙酸溶液提取,中性氧化铝吸附杂质后进行拉曼光谱检测.三聚氰胺线性范围为0.0050～0.075 mg/L,检出限为0.0015 mg/L,回收率在79.5％～124％之间,相对标准偏差小于8.8％(n=5);二聚氰胺线性范围为0.50～l0mg/L,检出限为0.15 mg/L,回收率在76.5％～112％之间,相对标准偏差小于9.4％(n=5).该方法相比常规表面增强拉曼光谱法,仅通过一种样品前处理手段即可对奶粉中的三聚氰胺或二聚氰胺进行定性检出及定量分析,相比色谱等检测方法具有样品前处理过程简单、耗时短等优点,在奶粉质量监控方面具有良好的应用前景.     

Development of a novel luminol chemiluminescent method catalyzed by gold nanoparticles for determination of estrogens

It has been found that gold nanoparticles (nano-Au) enhance the chemiluminescence (CL) of the luminol–hydrogen peroxide system and that estrogens inhibit these CL signals in alkaline solution. CL spectra, UV–visible spectra, X-ray photoelectron spectra (XPS), and transmission electron microscopy (TEM) were used to investigate the mechanism of the CL enhancement. On the basis of the inhibition, a flow-injection CL method has been established for determination of three natural estrogens. Under the optimized conditions, the linear range for determination of the estrogens was 0.07 to 7.0 μmol L⁻¹ for estrone, 0.04 to 10 μmol L⁻¹ for estradiol, and 0.1 to 10 μmol L⁻¹ for estriol. The detection limits were 3.2 nmol L⁻¹ for estrone, 7.7 nmol L⁻¹ for estradiol, and 49 nmol L⁻¹ for estriol, with RSD of 2.9, 2.6, and 1.8%, respectively. This method has been used for analysis of estrogens in commercial tablets and in urine samples from pregnant women.     

Simultaneous determination of three naturally occurring estrogens in environmental waters by high-performance liquid chromatography

A simple, sensitive and accurate reversed-phase high-performance liquid chromatographic (HPLC) method for simultaneous determination of three naturally occurring estrogenic steroids including estrone (E1), 17β-estradiol (E2) and estriol (E3) in environmental water samples was developed. Analytes were extracted with ethyl acetate solvents and preconcentrated prior to HPLC analysis. Separations were accomplished in <20 min using a reversed-phase C(18) column (4.6×250 mm id, 5 μm) with a gradient elution of mobile phase containing 3.0 mM ammonium acetate/acetonitrile mixtures (flow rate, 1.0 mL/min). UV light absorption responses at 205 nm were linear over a wide concentration range from 100,000 μg/L to the detection limits of 0.96 μg/L E1, 0.64 μg/L E2 and 0.78 μg/L E3. Quantitation was carried out by the peak area method. The relative standard deviation for the analysis of three estrogens was <3.0%. This method was applied for the simultaneous determination of estrogens in environmental water samples collected in Zhejiang, China. The higher concentrations of both E2 and E3 were found in Tang River and West Lake waters, and E1 was detected in lake water only. All three estrogens were below the detection limits in rain waters.     

Magnetic solid-phase extraction based on magnetic carbon nanotube for the determination of estrogens in milk

In this work, a novel method for the fabrication of magnetic carbon nanotubes based on 'aggregation wrap' was proposed. When carbon nanotubes and magnetic nanoparticles were vortically mixed in a solvent, the magnetic nanoparticles were wrapped into the carbon nanotube bundles that formed during the aggregation process, leading to the formation of magnetic carbon nanotubes. Thus, the resultant material can be separated from the solvent rapidly and conveniently by a magnet. Our investigation demonstrated that the 'aggregation wrap' mechanism for the preparation of magnetic composite is also applicable to other self-aggregated micro/nanomaterials, including graphene, graphite, C(60), etc. To testify the feasibility of the magnetic composites in sample preparation, the resultant magnetic carbon nanotubes were applied as sorbents for magnetic solid-phase extraction (MSPE) of estrogens in milk samples. Under optimized conditions, a rapid, convenient and efficient method for the determination of estrogens in milk samples was established by the combination of MSPE with high-performance liquid chromatography with fluorescence detector. The linearity range of the proposed method was 5-2000 μg/L with correlation coefficients (R) of 0.9983-0.9994. The limit of detection (LOD) for three estrogens ranged from 1.21 to 2.35 μg/L. The intra- and inter-day relative standard deviations (RSDs) were <9.3%. The reproducibility of the MSPE with different batches of magnetic carbon nanotubes was acceptable with RSD values <3.6%.     

高效液相色谱-串联质谱法测定牛奶和奶粉中的三聚氰酸

建立了牛奶和奶粉中三聚氰酸(CYA)的高效液相色谱-串联质谱(HPLC-MS/MS)测定方法。样品用乙腈提取并沉淀蛋白,经强阴离子交换柱富集和净化,AX色谱柱分离,HPLC-MS/MS法测定,内标法定量。50～2000 μg/L范围内CYA的线性关系良好(r≥0.999);在奶粉和牛奶基质中,添加200、500和1000 μg/kg 3个添加水平的回收率均在97%～121%之间,相对标准偏差(RSD)均小于4.8%;定量限(LOQ)为200 μg/kg。方法的前处理快速简便,净化效果好,准确度和精密度高,可用于牛奶和奶粉中CYA的测定。     

Stacking and simultaneous determination of estrogens in water samples by CE with electrochemical detection

A rapid and sensitive method based on transient ITP and field enhancement in CE with electrochemical detection at copper disk electrode was developed for the simultaneous separation and determination of three estrogens: estrone, 17β‐estradiol, and estriol. The effects of several important factors that influence the separation and detection were investigated. Under the optimum conditions, the estrogens could be separated in 0.06 mol/L sodium hydroxide solution within 14 min. With transient ITP by addition of 0.5% NaCl, a good linear response was obtained for three estrogens from 0.2 to 10 μmol/L, with correlation coefficients higher than 0.9993. The detection limits were 8.9 × 10^?8, 6.7 × 10^?8, and 1.1 × 10^?7 mol/L (S/N = 3) for estriol, 17β‐estradiol, and estrone, respectively. This method was successfully employed to analyze different water samples from waterworks, tap water, fishpond, and river samples with recoveries in the range of 90.8–108.9%, and RSDs < 4.69%. The satisfied results demonstrated that this method was of convenient preparation, high sensitivity, and good repeatability, which could be applied to the rapid determination of environmental water samples.     

Determination of anti-inflammatory drugs and estrogens in water by HPLC with UV detection

An analytical method based on LC and UV detection has been developed for the determination of anti-inflammatory compounds and estrogens in water samples. The drugs investigated were diclofenac, ketoprofen, ibuprofen, naproxen, clofibric acid, estriol, 17beta-estradiol, estrone and ethynylestradiol. The detection limits were in the range of 6-74 microg/L and 0.041 -0.16 mg/L for acidic pharmaceuticals and estrogens, respectively, using narrow-bore C18 analytical column. Analyte enrichment from water samples was achieved by SPE procedure using polymeric Strata-X cartridges. Average recoveries obtained from 2.5 L of surface water sample were in the range of 77-98%.