Dummy molecularly imprinted polymers (DMIPs) for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) were produced using three structural analogues as dummy template molecules. The chosen analogues were 4-(a...Dummy molecularly imprinted polymers (DMIPs) for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) were produced using three structural analogues as dummy template molecules. The chosen analogues were 4-(acetymethylamino)-1-(3-pyridyl)-butanol, 4- (methylamino)-1-(3-pyridyl)-1-butanol, and 1-(3-pyridyl)-1,4,-butanediol. The molecular recognition characteristics of the produced polymers were evaluated by X-ray photoelec- tron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). Interactions between NNAL and methacrylic acid should be cooperative hydrogen bonds while the ni- trogen atom of the pyridine ring and the oxygen atom of the nitroso group in NNAL are two of the hydrogen-bond acceptors. It was further demonstrated that DMIP synthesized by 4-(acetymethylamino)-1-(3-pyridyl)-butanol had the best binding performance by XPS and FT-IR. Then dummy molecularly imprinted solid phase extraction (DMISPE) was developed for the determination of the analyte using the hit polymer as the sorbing material. Under optimal conditions, the recovery of NNAL dissolved in standard solution reached 93%. And the investigated polymer exhibited much higher binding of NNAL when nicotine was acted as the competitive molecule. Also the proposed method was applied to the measurement of NNAL spiked in blank urine samples with recoveries ranging from 87.2% to 101.2%.展开更多
Silica gel-loaded (E)-N-(1-thien-2'-ylethylidene)-1,2-phenylenediamine (TEPDA) phase was synthesized based on physical adsorption approaches. The stability of a chemically modified TEPDA especially in concentra...Silica gel-loaded (E)-N-(1-thien-2'-ylethylidene)-1,2-phenylenediamine (TEPDA) phase was synthesized based on physical adsorption approaches. The stability of a chemically modified TEPDA especially in concentrated hydrochloric acid that was then used as a recycling and preconcentration reagent allowed the further uses of silica gel-loaded immobilized TEPDA phase. The application of this silica gel-loaded phase to sorption of a series of metal ions was performed by using different controlling factors such as the pH of the metal ion solution and the equilibration shaking time by the static technique. This difference was interpreted on the basis of selectivity incorporated in these sulfur containing silica gel-loaded TEPDA phases. Hg(Ⅱ) was found to exhibit the highest affinity towards extraction by these silica gel-loaded TEPDA phases. The pronounced selectivity was also confirmed by the determined distribution coefficients (Kd) of all the metal ions, showing the highest value reported for mercury(Ⅱ) extraction by the silica gel immobilized TEPDA phase. The potential applications of the silica gel immobilized TEPDA phase to selective extraction of mercury(Ⅱ) from aqueous solution were successfully accomplished and preconcentration of low concentration of Hg(Ⅱ) (30 pg·mL^-1) from natural tap water with a preconcentration factor of 200 for Hg(Ⅱ) off-line analysis was conducted by cold vapor atomic absorption analysis.展开更多
建立了一种可用于水产品及食用油中氟乐灵残留量分析的分散型固相萃取-气相色谱-负化学离子源质谱方法。水产品及食用油经乙腈提取,4℃冷藏后,采用分散型固相萃取法净化,由气相色谱-负化学离子源质谱选择离子监测技术进行测定与确证...建立了一种可用于水产品及食用油中氟乐灵残留量分析的分散型固相萃取-气相色谱-负化学离子源质谱方法。水产品及食用油经乙腈提取,4℃冷藏后,采用分散型固相萃取法净化,由气相色谱-负化学离子源质谱选择离子监测技术进行测定与确证,同位素内标法定量。在1~40μg / L 范围内氟乐灵农药的线性关系良好;方法定量限(LOQ)为0.02μg / kg;对鳗鱼、烤鳗、梭子蟹、小龙虾、猪油和橄榄油等6种复杂基质进行1.0、2.0和3.0μg / kg 等3个水平的添加回收试验,平均回收率均处于80%~100%之间,RSD≤10.3%;无干扰现象出现。该方法可作为水产品及食用油中氟乐灵残留检测的确证方法。展开更多
The treatment of wastewaters is crucial to maintain the ecological status of receiving waters,and thereby guarantee the protection of aquatic life and human health.Wastewater quality evaluation is conventionally based...The treatment of wastewaters is crucial to maintain the ecological status of receiving waters,and thereby guarantee the protection of aquatic life and human health.Wastewater quality evaluation is conventionally based on physicochemical parameters,but increasing attention has been paid to integrate physicochemical and biological data.Nevertheless,the regulatory use of fish in biological testing methods has been subject to various ethical and cost concerns,and in vitro cell-based assays have thus become an important topic of interest.Hence,the present study intends:(a) to evaluate the efficiency of two different sample pre-concentration techniques (lyophilisation and solid phase extraction) to assess the toxicity of municipal effluents on rat cardiomyoblast H9c2(2-1) cells,and (b) maximizing the use of the effluent sample collected,to estimate the environmental condition of the receiving environment.The gathered results demonstrate that the H9c2(2-1) sulforhodamine B-based assay is an appropriate in vitro method to assess biological effluent toxicity,and the best results were attained by lyophilising the sample as pre-treatment.Due to its response,the H9c2(2-1) cell line might be a possible alternative in vitro model for fish lethal testing to assess the toxicity of municipal effluents.The physicochemical status of the sample suggests a high potential for eutrophication,and iron exceeded the permissible level for wastewater discharge,possibly due to the addition of ferric chloride for wastewater treatment.In general,the levels of carbamazepine and sulfamethoxazole are higher than those reported for other countries,and both surpassed the aquatic protective values for long-term exposure.展开更多
Preconcentration/separation of Co(II), Fe(III), Pb(II), Cr(IIl), Cu(II) and Cd(II) ions using bis(5-bromo- 2-hydroxy-benzaldehyde)-2-methy1-1,5-pentane diimine (BBHBPDI) on SDS coated alumina has been ...Preconcentration/separation of Co(II), Fe(III), Pb(II), Cr(IIl), Cu(II) and Cd(II) ions using bis(5-bromo- 2-hydroxy-benzaldehyde)-2-methy1-1,5-pentane diimine (BBHBPDI) on SDS coated alumina has been reported. The influences of the analytical parameters including pH, ligand and SDS amount, type and concentration of eluent and sample volume on metal ions recoveries were investigated. At optimum values of all variables the relative standard deviation are between 2.5-2.7 and preconcentration factor was 375, while recoveries for all understudy metal ions are higher than 95%, determination limits are between 1.5-2.7. The method has been successfully applied to determination of Co(II), Fe(III), Pb(II), Cr(III), Cu(II) and Cd(II) ions content in some real samples.展开更多
文摘Dummy molecularly imprinted polymers (DMIPs) for 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) were produced using three structural analogues as dummy template molecules. The chosen analogues were 4-(acetymethylamino)-1-(3-pyridyl)-butanol, 4- (methylamino)-1-(3-pyridyl)-1-butanol, and 1-(3-pyridyl)-1,4,-butanediol. The molecular recognition characteristics of the produced polymers were evaluated by X-ray photoelec- tron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). Interactions between NNAL and methacrylic acid should be cooperative hydrogen bonds while the ni- trogen atom of the pyridine ring and the oxygen atom of the nitroso group in NNAL are two of the hydrogen-bond acceptors. It was further demonstrated that DMIP synthesized by 4-(acetymethylamino)-1-(3-pyridyl)-butanol had the best binding performance by XPS and FT-IR. Then dummy molecularly imprinted solid phase extraction (DMISPE) was developed for the determination of the analyte using the hit polymer as the sorbing material. Under optimal conditions, the recovery of NNAL dissolved in standard solution reached 93%. And the investigated polymer exhibited much higher binding of NNAL when nicotine was acted as the competitive molecule. Also the proposed method was applied to the measurement of NNAL spiked in blank urine samples with recoveries ranging from 87.2% to 101.2%.
基金Project supported by the National Natural Science Foundation of China (No. 20271025), the Natural Science Foundation of Shandong Province (No. L2003B01) and the State Key Laboratory of Crystal Materials, Shandong University.
文摘Silica gel-loaded (E)-N-(1-thien-2'-ylethylidene)-1,2-phenylenediamine (TEPDA) phase was synthesized based on physical adsorption approaches. The stability of a chemically modified TEPDA especially in concentrated hydrochloric acid that was then used as a recycling and preconcentration reagent allowed the further uses of silica gel-loaded immobilized TEPDA phase. The application of this silica gel-loaded phase to sorption of a series of metal ions was performed by using different controlling factors such as the pH of the metal ion solution and the equilibration shaking time by the static technique. This difference was interpreted on the basis of selectivity incorporated in these sulfur containing silica gel-loaded TEPDA phases. Hg(Ⅱ) was found to exhibit the highest affinity towards extraction by these silica gel-loaded TEPDA phases. The pronounced selectivity was also confirmed by the determined distribution coefficients (Kd) of all the metal ions, showing the highest value reported for mercury(Ⅱ) extraction by the silica gel immobilized TEPDA phase. The potential applications of the silica gel immobilized TEPDA phase to selective extraction of mercury(Ⅱ) from aqueous solution were successfully accomplished and preconcentration of low concentration of Hg(Ⅱ) (30 pg·mL^-1) from natural tap water with a preconcentration factor of 200 for Hg(Ⅱ) off-line analysis was conducted by cold vapor atomic absorption analysis.
文摘建立了一种可用于水产品及食用油中氟乐灵残留量分析的分散型固相萃取-气相色谱-负化学离子源质谱方法。水产品及食用油经乙腈提取,4℃冷藏后,采用分散型固相萃取法净化,由气相色谱-负化学离子源质谱选择离子监测技术进行测定与确证,同位素内标法定量。在1~40μg / L 范围内氟乐灵农药的线性关系良好;方法定量限(LOQ)为0.02μg / kg;对鳗鱼、烤鳗、梭子蟹、小龙虾、猪油和橄榄油等6种复杂基质进行1.0、2.0和3.0μg / kg 等3个水平的添加回收试验,平均回收率均处于80%~100%之间,RSD≤10.3%;无干扰现象出现。该方法可作为水产品及食用油中氟乐灵残留检测的确证方法。
基金The Portuguese Foundation for Science and Technology (FCT) supported the present study through a fellowship attributed to Elsa Teresa Rodrigues(SFRH/BPD/116152/2016),which was funded by the Human Potential Operating Program of the European Social Fund,and by the Portuguese budget through the Ministry of Education and Sciencedeveloped within the Fish Free Project(PTDC/AAG-TEC/4966/2014)+3 种基金supported by the FCT through national funds (3599-PPCDT)the co-funding of the European Regional Development Fund (POCI-01-0145-FEDER-016875)supported within the PT2020 Partnership Agreement and COMPETE 2020 by the centre for Functional Ecology Strategic Project (UID/BIA/04004/2013)the Coimbra Chemistry Center Strategic Project (UID/QUI/00313/2013)。
文摘The treatment of wastewaters is crucial to maintain the ecological status of receiving waters,and thereby guarantee the protection of aquatic life and human health.Wastewater quality evaluation is conventionally based on physicochemical parameters,but increasing attention has been paid to integrate physicochemical and biological data.Nevertheless,the regulatory use of fish in biological testing methods has been subject to various ethical and cost concerns,and in vitro cell-based assays have thus become an important topic of interest.Hence,the present study intends:(a) to evaluate the efficiency of two different sample pre-concentration techniques (lyophilisation and solid phase extraction) to assess the toxicity of municipal effluents on rat cardiomyoblast H9c2(2-1) cells,and (b) maximizing the use of the effluent sample collected,to estimate the environmental condition of the receiving environment.The gathered results demonstrate that the H9c2(2-1) sulforhodamine B-based assay is an appropriate in vitro method to assess biological effluent toxicity,and the best results were attained by lyophilising the sample as pre-treatment.Due to its response,the H9c2(2-1) cell line might be a possible alternative in vitro model for fish lethal testing to assess the toxicity of municipal effluents.The physicochemical status of the sample suggests a high potential for eutrophication,and iron exceeded the permissible level for wastewater discharge,possibly due to the addition of ferric chloride for wastewater treatment.In general,the levels of carbamazepine and sulfamethoxazole are higher than those reported for other countries,and both surpassed the aquatic protective values for long-term exposure.
文摘Preconcentration/separation of Co(II), Fe(III), Pb(II), Cr(IIl), Cu(II) and Cd(II) ions using bis(5-bromo- 2-hydroxy-benzaldehyde)-2-methy1-1,5-pentane diimine (BBHBPDI) on SDS coated alumina has been reported. The influences of the analytical parameters including pH, ligand and SDS amount, type and concentration of eluent and sample volume on metal ions recoveries were investigated. At optimum values of all variables the relative standard deviation are between 2.5-2.7 and preconcentration factor was 375, while recoveries for all understudy metal ions are higher than 95%, determination limits are between 1.5-2.7. The method has been successfully applied to determination of Co(II), Fe(III), Pb(II), Cr(III), Cu(II) and Cd(II) ions content in some real samples.