基于磁性活性炭的分散基质固相萃取-高效液相色谱检测水中双酚A

建立了一种以磁性分散基质固相萃取为预处理技术,结合高效液相色谱检测水样中双酚A的分析方法。制备磁性活性炭作为吸附材料,可以实现吸附材料与水相的彻底、简便的分离。方法的优化条件:吸附时间为15 min、0.5m L丙酮为洗脱剂,洗脱时间为2 min,水样的pH为4,加入25 g/L NaCl。在优化条件下,BPA检出限为0.02μg/L,线性范围为0.05~10μg/L(r=0.9995)。     

分子印迹磁性固相萃取/液相色谱法检测奶制品中的双酚A

以双酚A(BPA)为模板分子,磁性二氧化硅(Fe_3O_4@SiO_2)为载体,4-乙烯基吡啶(4-VP)为功能单体,采用表面分子印迹技术制备了双酚A磁性分子印迹聚合物微球(Fe_3O_4@SiO_2-MIPs)。通过红外光谱、透射电镜等对Fe_3O_4@SiO_2-MIPs进行了结构和形貌的表征。将制得的Fe_3O_4@SiO_2-MIPs作为磁性吸附剂,分离富集奶制品中的BPA,建立了分子印迹磁性固相萃取/液相色谱法测定奶制品中BPA的新方法。结果表明,在优化条件下,Fe_3O_4@SiO_2-MIPs对BPA具有良好的选择性,最大吸附容量达13.50 mg/g,在0.05~5.0 mmol/L浓度范围内有良好的线性关系(r2=0.993 4),方法检出限为0.037μg/L,样品加标回收率为86.2%~93.1%,相对标准偏差为2.9%~3.8%。该方法高效快速,选择性好,可用于牛奶样品中痕量BPA的检测。     

单分散磁性亚微米粒子固相萃取-液相色谱-串联质谱法测定牛奶中的双酚A

采用溶剂热还原法制备的单分散性Fe3O4磁性亚微米粒子(Fe3O4-magnetic submicron particles)进行固相萃取(SPE),结合高效液相色谱-串联质谱(HPLC-MS/MS)测定了牛奶中的双酚A(BPA)。对溶液的pH、磁性粒子用量、洗脱溶剂和体积等影响因素进行了优化,得到的最优萃取条件为: 溶液的pH 6,磁性粒子用量3.5 mg,用0.4 mL甲醇洗脱。以Agilent XDB C18柱为分析柱,流动相为乙腈-0.25 mmol/L氨水（80:20, v/v）溶液,在负离子模式下进行MS/MS测定。双酚A在1～100 μg/L范围内线性关系良好(r=0.9993);在3个添加水平下,回收率为85.3%～96.1%,相对标准偏差小于10%;通过不断稀释加标浓度确定方法的检出限(信噪比为3)为1.0 μg/L。该方法简单、准确,能用于牛奶中双酚A的快速测定。     

基于磁性C_(12)烷基壳聚糖硅胶复合材料磁固相萃取-高效液相色谱法测定双酚类化合物

基于磁性C_(12)烷基壳聚糖硅胶复合材料,建立了磁固相萃取-高效液相色谱法测定茶饮样品中5种双酚类化合物(BPs)的分析方法。研究表明,磁性C_(12)烷基壳聚糖硅胶复合材料对这5种BPs都具有很好的富集能力,富集率在96%～98%之间。采用2 mL乙腈在5 min内就可将富集的双酚化合物快速、完全洗脱。建立的BPs分析方法线性关系良好(R0.99),5种目标物的检出限范围为2.34～15.6μg/L,方法的精密度(RSDs,n=7)在1.5%～8.5%之间,加标回收率范围为86.0%～112.3%。方法可用于茶饮品中BPs的检测。     

磁性氮掺杂石墨烯固相萃取环境水样中的4种有机氯污染物

采用化学共沉淀法成功合成了磁性氮掺杂石墨烯纳米材料, 对其吸附性能进行了初步探讨.此磁性纳米材料对对氯间二甲苯酚的吸附不局限于均匀的单分子层吸附,吸附动力学符合准二级动力学模型.将其作为磁性固相吸附剂,通过对吸附剂用量、超声萃取时间、水样pH值、上样体积等条件的优化,建立了超声辅助磁性固相萃取-气相色谱/串联质谱同时测定环境水样中的三氯生(TCS)、对氯间二甲苯酚(PCMX)、六氯苯(HCB)和2,2′,4,4′,5,5′-六氯联苯(PCB-153) 4种有机氯污染物的方法. 在优化条件下,将6.0 mg Fe3O4/N-G分散于100 mL水样中,调节水样至pH 5,超声萃取15 s,磁性分离,3 mL乙醇和2 mL二氯甲烷分步洗脱,洗脱液氮吹定容,进行气相色谱-质谱联用分析.4种有机污染物在0.1~10 μg/L范围内与峰面积呈良好的线性关系,相关系数为0.9983~0.9999,检出限(S/N=3)和定量限(S/N=10)分别为0.05~0.6 ng/L和0.4~2.4 ng/L,3个加标浓度水平的回收率为68.3%~103.4%,日内、日间测定的相对标准偏差分别为3.3%~6.9%和3.4%~9.4%(n=6).本方法简单方便,易于操作,适用于环境水样中有机氯污染物的检测.     

分散液-液微萃取/高效液相色谱法测定水样中的痕量双酚A

建立了分散液-液微萃取与高效液相色谱联用技术测定水样中痕量双酚A(BPA)的方法. 通过对实验条件的筛选及优化, 得到最佳条件: 22.5 μL氯苯作萃取剂、0.5 mL丙酮作分散剂、0 min静止萃取时间、调节pH 3.2左右、10%离子强度及9 mL水样体积. 此条件下方法的线性范围为0.5~100 μg/L(R2=0.9941), 检出限为0.10 μg/L. 在BPA质量浓度为1 μg/L条件下, 方法回收率为87.8%~111.0%, 相对标准偏差8.3%(n=5), 富集倍数范围1905~2527. 对添加不同BPA浓度的自来水、地表水及回用中水进行分析, 回收率分别为(108±11.1)%, (107±13.2)%及(81.2±6.2)%(n=3). 在既定的色谱条件下, BPA的测定不受乙炔基雌二醇、雌二醇、雌三醇、雌酮和壬基酚等雌激素的干扰.     

分子印迹聚合物为涂层的吸附萃取搅拌棒在环境水样双酚A含量测定中的应用

以双酚A(BPA)为单体,利用整体材料“原位”聚合技术制备以分子印迹聚合物为涂层的吸附萃取搅拌棒(MIP-SBSE),然后与高效液相色谱(HPLC)-二极管阵列检测器联用,探讨其对环境水样BPA的选择萃取性能。优化萃取过程中吸附和解吸时间、解吸液种类以及基底pH值和离子强度对目标化合物的选择吸附性能。在最佳条件下,MIP-SBSE可对模板分子进行有效的选择吸附,线性范围为1.0～200 μg/L,检出限(S/N=3)和定量限(S/N=10)分别为0.28μg/L和0.94 μg/L。在实际水样分析中,具有良好的加标回收率,其值为96.0%～108.7%。研究结果表明,所建立的方法具有简便、灵敏和环境友好等特点。     

磁性石墨烯固相萃取荧光光度法测定一次性水杯中双酚A溶出量

通过水热反应合成了磁性石墨烯,以磁性石墨烯为磁固相萃取材料,结合荧光光度法建立了测定水中痕量双酚A的新方法。考察了磁性石墨烯用量、洗脱剂的类型和体积、萃取和洗脱的时间等参数的影响。在优化的实验条件下,方法的检出限为3.3 ng/L,线性范围0.01~0.5μg/L,相关系数0.9995,相对标准偏差为4.1%。方法应用于一次性水杯中双酚A溶出量的分析,加标回收率在96%~105%之间。     

固相萃取/高效液相色谱法测定饮用水中苯并(a)芘及双酚A

建立了饮用水中苯并(a)芘(Bap)和双酚A(BPA)同时测定的固相萃取/高效液相色谱方法。水样中苯并(a)芘和双酚A经ENVI-18固相萃取小柱富集后,采用C18色谱柱分离,以乙腈-水为流动相,梯度洗脱,荧光检测器检测。结果表明,苯并(a)芘和双酚A在0.1~20.0μg/L浓度范围内线性关系良好,相关系数大于0.999,检出限分别为0.2 ng/L和2.0 ng/L,样品加标回收率为86.1%~101%,相对标准偏差为2.9%~4.6%。该方法灵敏度高,选择性好,方便快捷,适用于饮用水中苯并(a)芘和双酚A的测定。     

在线固相萃取-高效液相色谱同时检测水中双酚A和双酚S

建立在线固相萃取-高效液相色谱法(On-line SPE-HPLC)同时测定水样中双酚A(BPA)和双酚S(BPS)的新方法。水样经过滤,用C18柱在线富集,用Spherigel C18分析柱(250 mm×4.6 mm,5μm)进行HPLC分析,以乙腈-水为流动相梯度洗脱(0~15 min,乙腈-水由70/30(V/V)变为80/20(V/V)),用高效液相色谱-二极管阵列检测器(HPLC-DAD)进行定量分析,检测波长为323 nm。BPA在0.05~5μg/L范围内,BPS在0.07~5μg/L范围内,线性关系良好,相关系数R~20.999。BPA和BPS检测限(LOD)分别为0.017和0.028μg/L,定量限(LOQ)分别为0.033和0.057μg/L。加标0.2μg/L BPA和BPS时,回收率在90%~98%内,相对标准偏差(n=6)在2%~6%内。本法适用于环境水样中BPA和BPS的同时测定。     

替代模板分子印迹聚合物的制备及其用于人尿、牛血清和啤酒中7种双酚类物质的选择性固相萃取

以酚酞(PP)为替代模板,采用本体聚合法制备了选择性识别7种双酚类物质(BPs)的分子印迹聚合物(MIP)。将制备的PP-MIP用作固相萃取(SPE)填料,成功应用于人尿、牛血清和啤酒样品中7种BPs的分离净化。建立了同时测定人尿、牛血清和啤酒样品中的7种BPs的MIP-SPE-HPLC分析方法。3种样品中7种BPs的方法检出限范围均为1.2~2.0 μg/L。结果表明,7种BPs在0.02~2 mg/L范围内线性关系良好,相关系数(r)大于0.9998;空白样品中加标水平为100和500 μg/L的回收率范围为90.1%~107.1%,相对标准偏差(RSD)不高于8.1%。该方法简便、准确、灵敏、可靠,可用于人尿、牛血清和啤酒中7种BPs的快速检测。     

环境样品中双酚类化合物的固相萃取研究进展

双酚类化合物作为一类内分泌干扰物广泛存在于环境介质中,经过多种途径迁移至人体后,可对人体产生内分泌毒性、细胞毒性、基因毒性、生殖毒性、二噁英毒性和神经毒性,已被加拿大政府风险评估识别为进一步优先控制名录。随着环境领域对双酚类化合物的广泛关注,相关研究工作逐渐向水、沉积物、灰尘和生物样品等多介质开拓。但是,由于不同环境样品在基质复杂性和污染物浓度水平等方面存在显著差异,开发提取效率高、净化选择性好、普适性强、操作简单、高通量的提取和净化方法,有助于实现环境介质中双酚类化合物的高灵敏、批量检测。近年来,新型前处理技术发展迅速,尤其是固相萃取技术,在双酚类化合物提取与净化方面取得了长足的发展,不仅在一定程度上克服了传统提取净化方法存在的耗时、耗力和耗溶剂等不足,而且为新型污染物分析提供了更多的技术支持。该文简述了典型双酚类化合物的理化性质、用途用量和环境危害,重点围绕新型固相萃取吸附剂开发和固相萃取模式转变两个方面,总结了固相萃取在双酚类化合物提取净化方法方面取得的进展。商品化固相萃取产品普适性强,在环境监测领域应用范围较广,适用于双酚类化合物的产品种类有限;新型吸附剂研发聚焦吸附容量(如介孔硅材料、碳纳米材料、金属-有机框架材料、环糊精)和选择性(如分子印迹聚合物和混合模式离子交换聚合物)两个方面,种类多样化可满足不同检测需求;越来越多的高灵敏分析仪器不断推向市场,为适应新的发展形势,固相萃取模式正逐渐向微型化、自动化、简易化等方向发展,如QuEChERS、固相微萃取、磁固相萃取等。     

全芳香族热致液晶聚合物与热塑性树脂聚砜的原位复合材料

用自制的四种全芳香族热致液晶聚合物ＢＰ ＬＣＰ、ＢＰＭ ＬＣＰ、ＢＰＡ ＬＣＰ、ＢＰＳ ＬＣＰ与热塑性树脂聚砜（ＰＳＦ）熔融共混，制备了一系列原位复合材料．研究了所得材料的微观形态、热性能、力学性能等，结果显示：四种液晶聚合物中，ＢＰ ＬＣＰ，ＢＰＳ ＬＣＰ在所用加工条件下可在ＰＳＦ中取向成纤，而且这两种共混物断面上存在皮 核效应；ＢＰＭ ＬＣＰ和ＢＰＡ ＬＣＰ未成纤，均以球状存在于ＰＳＦ中．这四种液晶聚合物与ＰＳＦ的相容性较差，各共混物的Ｔｇ均分别接近于二纯组分的Ｔｇ值，ＳＥＭ照片上明显的相界面也能说明以上问题．液晶聚合物对ＰＳＦ有增强作用，但增强效果不很显著，这可能是二者相容性较差所致     

Cetyltrimethylammonium Bromide(CTAB)-Ionic Liquid Composite Modified Electrode for Sensitive Cyclic Voltammetric Determination of Bisphenol A

A sensitive electrochemical sensor for determining bisphenol A(BPA) was designed. The sensor was a glassy carbon electrode modified with the surfactant cetyltrimethylammonium bromide and the ionic liquid 1-decyl-3-methylimidazolium tetrafluoroborate. The ability of the new sensor to measure BPA was investigated in cyclic voltammetry experiments. Under optimized conditions, the sensor gave a linear response range for BPA of 2.19×10^-7-3.28×10^-5 mol/L and a detection limit of 7.31×10^-8 mol/L(S/N=3). BPA could be determined with a lower detection limit, a wider linear range, and more sensitivity using the sensor than using other electrochemical sensors or high performance liquid chromatography with UV detection. The new sensor was used to determine BPA in tap water with recoveries of 97.5%-98.7% and a relative standard deviation <2.9%. The results show that the sensor can be used to determine trace BPA concentrations in tap water.     

Decontamination of bisphenol A from aqueous solution by graphene adsorption

The decontamination of bisphenol A (BPA) from aqueous solution by graphene adsorption was investigated. The maximum adsorption capacity (q(m)) of graphene for BPA obtained from a Langmuir isotherm was 182 mg/g at 302.15 K, which was among the highest values of BPA adsorption compared with other carbonaceous adsorbents according to the literature. Both π-π interactions and hydrogen bonds might be responsible for the adsorption of BPA on graphene, and the excellent adsorption capacity of graphene was due to its unique sp(2)-hybridized single-atom-layer structure. Therefore, graphene could be regarded as a promising adsorbent for BPA removal in water treatment. The kinetics and isotherm data can be well described by the pseudo-second-order kinetic model and the Langmuir isotherm, respectively. The thermodynamic studies indicated that the adsorption reaction was a spontaneous and exothermic process. Besides, the presence of NaCl in the solution could facilitate the adsorption process, whereas the alkaline pH range and higher temperature of the solution were unfavorable.     

Molecularly imprinted polymer microspheres prepared by Pickering emulsion polymerization for selective solid-phase extraction of eight bisphenols from human urine samples

The bisphenol A (BPA) imprinted polymer microspheres were prepared by simple Pickering emulsion polymerization. Compared to traditional bulk polymerization, both high yields of polymer and good control of particle sizes were achieved. The characterization results of scanning electron microscopy and nitrogen adsorption–desorption measurements showed that the obtained molecularly imprinted polymer microsphere (MIPMS) particles possessed regular spherical shape, narrow diameter distribution (30–60 μm), a specific surface area (S_BET) of 281.26 m² g⁻¹ and a total pore volume (V_t) of 0.459 cm³ g⁻¹. Good specific adsorption capacity for BPA was obtained in the sorption experiment and good class selectivity for BPA and its seven structural analogs (bisphenol F, bisphenol B, bisphenol E, bisphenol AF, bisphenol S, bisphenol AP and bisphenol Z) was demonstrated by the chromatographic evaluation experiment. The MIPMS as solid-phase extraction (SPE) packing material was then evaluated for extraction and clean-up of these bisphenols (BPs) from human urine samples. An accurate and sensitive analytical method based on the MIPMS-SPE coupled with HPLC-DAD has been successfully established for simultaneous determination of eight BPs from human urine samples with detection limits of 1.2–2.2 ng mL⁻¹. The recoveries of BPs for urine samples at two spiking levels (100 and 500 ng mL⁻¹ for each BP) were in the range of 81.3–106.7% with RSD values below 8.3%.     

Non‐Covalent Functionalization of Graphene with Bisphenol A for High‐Performance Supercapacitors

The reduced graphene oxide (RGO)/bisphenol A (BPA) composites were prepared by an adsorption‐reduction method. The composites are characterized by X‐ray diffraction (XRD), UV‐vis, thermogravimetric (TG) analysis, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM). The results confirm that BPA is adsorbed on the basal plane of RGO by π‐π stacking interaction. Furthermore, the electrochemical behaviors were evaluated by cyclic voltammetry, galvanostatic charge/discharge techniques and electrochemical impedance spectroscopy (EIS). The results show that the RGO/BPA nanocomposites exhibit ultrahigh specific capacitance of 466 F·g^?1 at a current density of 1 A·g^?1, excellent rate capability (more than 81% retention at 10 A·g^?1 relative to 1 A·g^?1) and superior cycling stability (90% capacitance decay after 4000 cycles). Consequently, the RGO/BPA nanocomposites can be regarded as promising electrode materials for supercapacitor applications.     

双酚A分子印迹聚合物为萃取介质搅拌饼固相萃取的制备及其萃取性能研究

以双酚A为模板,4-乙烯基吡啶为单体,利用整体材料"原位"聚合技术制备分子印迹聚合物为基质的萃取饼,并与利用一次性注射器空管加工而成的萃取器相结合,建立了分子印迹搅拌饼固相萃取(MIP-SCSE)技术。考察了制备条件对MIP-SCSE选择吸附性能的影响。在此基础上,与高效液相色谱-二极管阵列检测器联用,探讨MIP-SCSE对环境水样中双酚A及其它酚类物质的选择萃取性能,考察萃取过程中基底离子强度、pH值以及吸附与解吸时间等萃取条件对萃取性能的影响。结果表明;在最佳萃取条件下,MIP-SCSE对模板分子及其它酚类物质具有一定选择性能和较高的富集能力,对双酚A的线性范围为1.0～200μg/L;检出限LOD(S/N=3)为0.67μg/L;定量限LOQ(S/N=10)为2.24μg/L。在实际水样分析中,模板分子加标回收率为86.2%～112.2%。在MIP-SCSE使用过程中,萃取饼不与容器壁接触,因此具有优良的使用寿命,至少可连续使用600 h。     

Novel sponge-like molecularly imprinted mesoporous silica material for selective isolation of bisphenol A and its analogues from sediment extracts

Bisphenol A (BPA) imprinted sponge mesoporous silica was synthesized using a combination of semi-covalent molecular imprinting and simple self-assembly process. The molecularly imprinted sponge mesoporous silica (MISMS) material obtained was characterized by FT-IR, scanning electron microscopy, transmission electron microscopy, and nitrogen adsorption–desorption measurements. The results show that the MISMS possessed a large specific surface area (850.55 m² g⁻¹) and a highly interconnected 3-D porous network. As a result, the MISMS demonstrated a superior specific adsorption capacity of 169.22 μmol g⁻¹ and fast adsorption kinetics (reaching equilibrium within 3 min) for BPA. Good class selectivity for BPA and its analogues (bisphenol F, bisphenol B, bisphenol E and bisphenol AF) was also demonstrated by the sorption experiment. The MISMS as solid-phase extraction (SPE) material was then evaluated for isolation and clean-up of these bisphenols (BPs) from sediment samples. An accurate and sensitive analytical method based on the MISMS–SPE coupled with HPLC–DAD has been successfully established for simultaneous determination of five BPs in river sediments with detection limits of 0.43–0.71 ng g⁻¹ dry weight (dw). The recoveries of BPs for lyophilizated sediment samples at two spiking levels (50 and 500 ng g⁻¹ dw for each BP) were in the range of 75.5–105.5% with RSD values below 7.5%.     

磁性石墨烯@聚多巴胺纳米复合材料分离去除水中双酚A

本文通过水热法和多巴胺的自我团聚反应合成了磁性石墨烯@聚多巴胺(PDA@MG)纳米复合材料,该材料具有表面积大,含有丰富的π电子共轭体系、很好的水溶液分散性,易分离及可重复使用等特点。以PDA@MG为吸附剂材料,研究了其对水溶液中双酚A(BPA)的吸附性能。考察了吸附时间、温度、溶液的pH、吸附剂的用量等因素对该材料吸附性能的影响。结果表明在优化实验条件下,PDA@MG对BPA的最大吸附容量为151.3mg/g。PDA@MG具有优异的循环吸附性能,经过10次循环使用后其吸附能力没有明显减弱。