Synthesis and Solid Phase Extraction Performance Study of NNAL-specific Molecularly Imprinted Polymers Using Dummy Templates

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%.

Thermodynamic modeling and phase diagram prediction of salt lake brine systemsⅡ.Aqueous Li^(+)-Na^(+)-K^(+)-SO_(4)^(2-) and its subsystems

It is still a challenging task to accurately and temperature-continuously express the thermodynamic properties and phase equilibrium behaviors of the salt-lake brine with multi-component,multitemperature and high concentration.The essential subsystem of sulfate type brine,aqueous Li^(+)-Na^(+)-K^(+)-SO_(4)^(2-) and its subsystems across a temperature range from 250 K to 643 K are investigated with the improved comprehensive thermodynamic model.Liquid parameters(Δg_(IJ),Δh_(IJ),and ΔC_(p,IJ))associated with the contributions of Gibbs energy,enthalpy,and heat capacity to the binary interaction parameters,i.e.the temperature coefficients of eNRTL parameters formulated with a Gibbs Helmholtz expression,are determined via multi-objective optimization method.The solid constantsΔ_(f)G_(k)°^((298.15))andΔ_(f)H_(k)°^((298.15))of11 solid species occurred in the quaternary system are rebuilt from multi-temperature solubilities.The modeling results show the accurate representation of(1)solution properties and binary phase diagram at temperature ranges from eutectic points to 643 K;(2)isothermal phase diagrams for Li_(2)SO_(4)-Na_(2)SO_(4)-H_(2)O,Li_(2)SO_(4)-K_(2)SO_(4)-H_(2)O and Na_(2)SO_(4)-K_(2)SO_(4)-H_(2)O ternary systems.The predicted results of complete structure and polythermal phase diagram of ternary systems and the isothermal phase diagrams of quaternary system excellently match with the experimental data.

液相色谱-质谱联用测定乌头碱血药浓度及其药代动力学参数的方法学研究

乌头碱(aconitine)是存在于乌头属多种植物中的一种双酯二萜生物碱,具有镇[1]、抗炎[2]、抗癫痫[3]、抗肿瘤[4]、提高免疫功能[5]等多种生理活性,但因其具有强烈的心脏毒性和神经毒性,安全系数小,治疗剂量与中毒剂量接近(小鼠LD501.8mg/kg,op;人绝对致死量为2～5mg)[7],限制了对该化合物作为药用的进一步研究,目前仅将其作为致心率失常模型的工具药使用,尚未见其药代动力学的报道.在本文中首次应用液相色谱-质谱联用法对乌头碱在大鼠体内的药代动力学进行了研究.……

液相色谱-串联质谱同时测定禽肉组织中盐酸金刚烷胺、盐酸金刚乙胺、地塞米松、替米考星及喹乙醇代谢物的残留量

建立了同时测定禽肉组织中盐酸金刚烷胺、盐酸金刚乙胺、地塞米松、替米考星及喹乙醇代谢物残留量的液相色谱-串联质谱分析方法.样品用2 mol/L氢氧化钠溶液水解,盐酸调节pH值后,以乙腈作为提取溶剂,经C18固相萃取柱净化.各待测物分别经0.1％甲酸甲醇溶液和氨化甲醇（0.1％氨水）洗脱,Phe-nomenex Kinetex C1s（100 mm×4.6 mm,2.6 μm）色谱柱进行分离,采用0.1％甲酸（含5 mmol/L乙酸铵）-甲醇作流动相,梯度洗脱,串联质谱法对5种药物含量进行测定.结果表明,5种药物在2 ～ 100 μg/L范围内线性关系良好,相关系数为0.996 2 ～0.999 8.在加标浓度为5～50 μg/kg的禽肉组织中,这5种药物的加标回收率为73.7％ ～92.3％,相对标准偏差（n=5）为3.9％ ～ 16.6％,检出限为0.2～ 3.0 μg,/kg,定量下限为0.7～ 10 μg/kg.方法快速、简便、经济实用,符合法规要求,可满足日常检测的需要.

气相色谱-离子阱二级质谱法测定猪肉中的氢化泼尼松和甲基氢化泼尼松残留

建立了固相萃取-气相色谱-离子阱二级质谱（GC-MS/MS）测定猪肉中氢化泼尼松和甲基氢化泼尼松残留量的分析方法。待测药物用乙腈提取,C18柱净化,K2Cr2O7氧化,GC-MS/MS测定。采用DB-5毛细管柱分离,电子轰击电离源二级质谱监测模式检测,外标法定量。方法的线性关系良好,线性相关系数均大于0.99,线性范围为2-50μg/kg;氢化泼尼松和甲基氢化泼尼松的回收率为56%-84%。两种药物的检测限和定量限均分别为1μg/kg和2μg/kg。

固相萃取-气相色谱-质谱法同时测定水中9种药品及个人护理用品

采用固相萃取-气相色谱-质谱联用技术，建立了水体中9种药品及个人护理用品（水杨酸、萘普生、布洛芬、对乙酰氨基酚、降固醇酸、三氯生、双氯酚酸、酮洛芬和双酚 A）的定量分析方法。水样品经稀盐酸调节至 pH =3后，采用 Oasis HLB 固相萃取小柱进行富集净化；选用三甲基氢氧化硫（ TMSH）为衍生化试剂，在常温条件下对目标物进行快速甲基化；以气相色谱-质谱法选择离子监测模式（GC-MS-SIM）进行检测，由2，4，5-涕丙酸为内标进行定量分析。本实验分别对固相萃取和衍生化等前处理条件进行了系统的研究。在优化的实验条件下，方法的回收率为50.7～115.4％，相对标准偏差均不高于10％，检出限为0.03～0.30μg / L，定量限为0．15～1．50μg / L。利用该方法对东莞市某农田灌溉水进行了分析，4种目标物在样品中有检出，最大质量浓度范围为0.176～0.998μg / L。结果表明该方法操作简便，灵敏可靠。

气相色谱-负化学源质谱联用法测定水产品及食用油中氟乐灵的残留量

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。

Extraction of Phenylalanine Phase Systems Containing Enantiomers by Aqueous Two Combinatorial Chiral Selector

In order to obtain a better enantioselectivity of phenylalanine enantiomers and establish the optimal chiral ex- traction conditions, the distribution behavior was investigated in aqueous two-phase systems which were composed of polyethylene glycol and ammonium sulfate containing combinatorial chiral selector： β-cyclodextrin and HP-β-cyclodextrin. The influence of the molar concentration ratio of combinatorial chiral selectors, the total molar concentration of combinatorial chiral selectors, pH value, buffer type and its concentration were thoroughly studied, respectively. The results show that the enantioselectivity reaches 1.53 under the optimal chiral extraction conditions This extraction is a potential economical and effective way for chiral resolution.

Selective Pre-concentration and Solid Phase Extraction of Mercury（Ⅱ） from Natural Water by Silica Gel-loaded （E）-N-（1-Thien-2＇-ylethylidene）-1,2-phenylenediamine Phase

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.

Self-assembled α-MnO2 urchin-like microspheres as a high-performance cathode for aqueous Zn-ion batteries

Aqueous Zn-ion batteries(AZIBs)are one of the promising battery technologies for the green energy storage and electric vehicles.As one attractive cathode material for AZIBs,α-MnO2 materials exhibit superior electrochemical properties.However,their long-term reversibility is still in great suspense.Considering the decisive effect of the structure and morphology on theα-MnO2 materials,hierarchicalα-MnO2 materials would be promising to improve the cycle performance of AZIB.Here,we synthesized theα-MnO2 urchin-like microspheres(AUM)via a self-assembled method.The porous microspheres composed of one-dimensionalα-MnO2 nanofibers with high crystallinity,which improved the surface area and active sites for Zn2+intercalation.The AUM-based AZIB realized a high initial capacity of 308.0 mA hg-1,and the highest energy density was 396.7 W hkg-1.The kinetics investigation confirmed the high capacitive contribution and fast ion diffusion of the AUM.Ex-situ XRD measurement further verified the synergistic insertion/extraction of H+and Zn2+ions during the charge/discharge process.The superiority of the AUM guaranteed good electrochemical performance and reversible phase evolution,and this application would promote the follow-up research on the advanced AZIB.

Rat cardiomyocyte H9c2(2-1)-based sulforhodamine B assay as a promising in vitro method to assess the biological component of effluent toxicity

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.

Preconcentration/Separation of Some Metal Ions Using Sodium Dodecyl Sulfate Coated Alumina Modified with Bis（5-bromo- 2-hydroxy-benzaldehyde）-2-methyl-1,5-pentane Diimine （BBHBPDI） Prior to Their Flame-AAS Determination

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.

The impact of a Wastewater Treatment Works in Southern Gauteng, South Africa on efavirenz and nevirapine discharges into the aquatic environment

There has been growing concern regarding the pollution of the aquatic environment with synthetic organic chemicals.Antiretroviral drugs,such as efavirenz and nevirapine,are pharmaceutical drugs and are referred to as emerging contaminants.Such drugs can be environmentally persistent and may be expected to pose potential risks to drinking water supplies.Sources of pharmaceutical drugs include effluents from Wastewater Treatment Works(WWTPs),hospital and pharmaceutical production facilities and the incorrect disposal of unused and expired medicines.Currently there are no monitoring programs and legislative guidelines for their regulations in South Africa.The aims of this study were firstly to develop a semi-quantitative method to extract and analyse efavirenz and nevirapine in the primary settling tank sludge.Secondly to use that method,and an existing method for liquid wastewater samples,to monitor the concentrations of efavirenz and nevirapine as the wastewater passes through the different stages of purification(anoxic;aerobic;pre and post chlorination)in the WWTP.This was repeated weekly over a period of 4 weeks.Thirdly,to determine if binding of efavirenz and nevirapine to the solids in the WWTP played a role in the removal of these compounds from the WWTP liquid phase.No references to the analysis of ARVDs in WWTP sludge were found in the literature.Grab samples of wastewater and sludge samples were collected from a WWTP(activated sludge treatment process)weekly for 4 weeks.Liquid samples were extracted solid phase extraction,solid samples were extracted using sonication followed by a QuEChERs clean-up.Sample extracts were then subjected to gas chromatography-time of flight mass spectrometry for analyte determination.Efavirenz concentrations entering the WWTP ranged between 5500 to almost 14000 ng/L.The removal of efavirenz by the WWTP ranged between 27 and 71%.The largest removal occurred in the anoxic zone,smaller amounts were removed in the aerators.Slight increases in efavirenz concentrations were found after chlorination and the final effluent into the river post maturation ponds again were slightly lower.Solids were found to contain efavirenz at concentrations between 17 and 43 mg/kg dried primary settling tank sludge and it is proposed that this binding to the solids is the main mechanism of removal of efavirenz from the wastewater stream as it passes through the WWTP.Although an order of magnitude lower nevirapine concentrations displayed the opposite behaviour and gradually increased through the various stages of purification in the WWTP.Minor fluctuations occurred but the concentrations of nevirapine were higher at the effluent(between 92 and 473 ng/L)than those entering the WWTP.No nevirapine was detected in the PST sludge.The increase in nevirapine concentrations are likely to be the result of the de-conjugation of the hydroxylated metabolites of nevirapine in the WWTP,its resistance to degradation and the lack of binding of the nevirapine to the PST sludge.