单克隆抗体间接竞争ELISA测定水体中氟虫腈

制备了氟虫腈单克隆抗体 ,在此基础上建立了水体中氟虫腈测定的间接竞争性酶联免疫吸附测定 (ELISA)法 .在优化条件下 ,氟虫腈测定的线性浓度范围为 1 0 -1 μg·L-1 ～ 1 0 3μg·L-1 ,最低检出浓度 (I1 0 )为 0 0 8μg·L-1 ,检测灵敏度 (I50 )为6 6 8μg·L-1 ;常见的几种与氟虫腈结构类似的农药的交叉反应率均低于 1 % ,不干扰氟虫腈的检测 ;2 0 %丙酮、5 %甲醇、2 %二甲基甲酰胺、2 %乙腈和 2 %乙酸乙酯基本不影响免疫测定 .利用建立的间接竞争性ELISA方法检测不同水样中氟虫腈 ,结果表明不同水样均可直接进行测定 ,方法的精密度和准确度均符合残留测定的要求     

同步衍生超声乳化微萃取气相色谱法测定环境水样中的苯胺类化合物

本研究建立了一种针对环境水样中苯胺类化合物检测的新方法——同步衍生超声乳化微萃取气相色谱法(SDUSAEME-GC-FID).通过氯甲酸丁酯(作为衍生剂/萃取相)的用量、超声时间、样品溶液p H值、离子强度和离心条件等因素对衍生/萃取效果影响的实验研究,确定了最优条件的关键性控制参数.结果表明,在选定条件下分析测定环境水样中5种苯胺类化合物,在6~60 000μg·L-1浓度范围内线性良好,相关系数R2为0.999 7~0.999 9,检测限LOD(3倍信噪比)为1.1~4.1μg·L-1,相对标准偏差RSD(n=6)为2.4%~5.7%,富集系数EF为317~846,测定7种实际环境水样的相对回收率RR为86.8%~105.5%.本方法具有操作简便、灵敏度高、经济环保的特点,可以作为检测环境水样中苯胺类化合物的一种首选方法.     

总微囊藻毒素免疫检测及其预处理方法研究

在验证广谱型微囊藻毒素酶联免疫分析试剂盒性能基础上,主要研究了基于我国与美国分别推荐的水样预处理方式所检测的地表水中微囊藻毒素浓度差异.结果表明：(1)酶联免疫分析试剂盒对微囊藻毒素-LR(MC-LR)的检出限为0.04μg·L^-1,并在0.08～1.00μg·L^-1的浓度范围内表现出良好的线性检测范围;(2)基于我国与美国分别推荐的水样预处理方式,后者测得的微囊藻毒素浓度普遍高于前者(最大差值：前者未检出,后者为(0.25±0.01)μg·L^-1),且基于两者所测试的地表水样中的微囊藻毒素浓度均低于世界卫生组织(WHO)对饮用水中MC-LR所设定的残留限值;(3)酶联免疫分析试剂盒在对上述未检出水样进行加标检测时,回收率为80%～120%,变异系数低于16%,表明上述地表水中微囊藻毒素的检测结果具有较高的准确度.     

乙腈和正己烷对环境特征污染物免疫传感分析的影响

利用前期研发的倏逝波全光纤免疫传感系统,使用间接竞争免疫模式对双酚A(bisphenol A,BPA)进行了定量分析,其检测灵敏度可达0.2μg·L~(-1),线性检测区间为0.3~33.4μg·L~(-1).重点考察了乙腈和正己烷两种常用有机溶剂对双酚A免疫传感分析的影响,初步探讨了有机溶剂对免疫传感分析的影响机制.结果表明,正己烷含量高达10%都不会对双酚A免疫传感分析产生明显影响,而乙腈的影响比较大.当乙腈含量较低时,可用于双酚A的定量检测;而当乙腈含量较高时,可完全抑制均相溶液中抗体抗原之间的亲和反应,不能用于双酚A的定量分析.其原因可能是乙腈取代了一部分结合在抗体表面的水分子,导致抗体构象改变或者抗体与抗原的亲和力变化而造成的.     

西藏地表水中砷的分布

通过系统地采集森格藏布和雅鲁藏布地表水样,研究了两流域水体中砷的分布.结果表明不同水体中砷的含量不同,其由高至低依次为:热泉水(4 920μg.L-1±1 520μg.L-1,n=2)>盐(咸)水湖水(2 180μg.L-1±3 840μg.L-1,n=7)>井水(194μg.L-1,n=1)>淡水湖水(163μg.L-1±202μg.L-1,n=2)>河水(35.5μg.L-1±57.0μg.L-1,n=74),森格藏布和雅鲁藏布上游存在高砷河水,森格藏布河水砷平均含量(58.4μg.L-1±69.9μg.L-1,n=39)明显高于雅鲁藏布(10.8μg.L-1±16.9μg.L-1,n=30).采集的热泉水、盐咸湖水、井水以及43.2%的河水样品中砷的含量均高于10μg.L-1,森格藏布和雅鲁藏布分别为两流域内居民重要的饮用水源,居民具有患上地方性砷中毒的风险.     

应用基于单克隆抗体的免疫传感器检测环境中的芘和苯并芘

多环芳烃是一类普遍存在的环境污染物,可以诱发癌症,对人们的健康造成严重威胁.本研究利用一种四环芳烃芘的衍生物作为半抗原,利用活泼酯法合成人工抗原免疫小鼠研制多环芳烃单克隆抗体.通过非竞争性ELISA与竞争性ELISA相结合的筛选方式得到一株单克隆抗体,命名为6A6.该抗体能特异性识别芘和苯并芘,其IC50值分别为8.1μg·L-1和6.8μg·L-1,对其他多环芳烃的交叉反应率均低于5%.在此基础上,建立了免疫传感器法对芘和苯并芘进行检测,线性范围为0.2~10.0μg·L-1.利用该方法对添加在水样中的样品进行回收,并与传统ELISA方法进行比对,结果证明传感器法检测更加快速且灵敏度更高.该方法可以用于含有芘和苯并芘的环境样品的快速筛选,可以在10 min内初步获得检测结果.     

固相萃取-高效液相色谱-质谱联用法检测环境水样中五种持久性有机污染物

持久性有机污染物(POPs)是指能通过环境降解,持久存在于各种大气、残留物、土壤、水及生物体内,通过生物食物链累积、并对人类健康造成有害影响的化学物质。本文建立了固相萃取(SPE)和高效液相色谱-质谱联用分析方法(HPLC-MS),同时定量测定环境水样中全氟辛酸(PFOA)、全氟辛磺酰酸(PFOS)、全氟己酸(PFHA)、双酚A(BPA)、3-羟基-四溴联苯醚(3-OH-BDE-47)5种持久性有机污染物。该方法在1~1 000 ng·m L-1的范围内具有良好的线性关系,检测限在1~8 ng·L-1,水样加标回收率为93.2%~110.1%,相对标准偏差(RSD)为2.7~9.1%,可以满足复杂水样中相关POPs的分析检测。     

恩诺沙星完全抗原的合成及间接竞争ELISA方法的建立

为了建立环境新型抗生素类污染物恩诺沙星的免疫检测方法,采用间接竞争ELISA方法,用酶标仪测定酶标二抗与底物反应生成的有色产物量来确定恩诺沙星含量.研究了恩诺沙星完全抗原的合成方法,以及间接竞争ELISA的优化条件和实际水样的检测效果.结果表明,通过碳二亚胺法(EDC+NHS)成功合成了恩诺沙星的理想完全抗原,采用BCA法测定完全抗原浓度,紫外吸收法和MADLI-TOF MS法测得完全抗原的偶联比为14~16.建立的恩诺沙星间接竞争ELISA检测方法,检测限为1.92μg·L~(-1),定量检测区间为7.33~238.24μg·L~(-1).采用优化后的实验条件测定了清华大学地下水和饮用水配制的恩诺沙星加标样品,发现所有样品的变异系数和回收率分别为3%~11%和82%~122%,表明建立的间接竞争ELISA方法适用于实际水样中恩诺沙星的快速简便检测.     

ABTS显色分光光度法测定水中微量高锰酸钾

基于KMnO4与2,2'-联氮-双-(3-乙基苯并噻唑啉-6磺酸)(ABTS)反应产生的绿色自由基在415 nm处有最大吸收值,建立了一种利用分光光度计测定水中低浓度KMnO4(0～4.66 μmol·L-1)的方法.在pH=2.1、ABTS过量(28.4 μmol·L-1)的条件下,KMnO4与ABTS反应的化学计量关系为1:5,产生的绿色自由基能够稳定存在,其在波长415 nm处的摩尔吸收系数为ε=(3.34±0.04)×104L·mol-1·cm-1.该方法对高锰酸钾的检测限(置信区间90%)为0.01 μmol·L-1(1.6μg·L-1,以KMnO4计).     

生物表面活性剂产生菌犁头霉菌(Absidia orchidis)的筛选及发酵条件优化

采用植物油为唯一碳源,设计选择培养基,从饭店下水道污泥中筛选出生物表面活性剂产生菌.结果分离到12株菌,其中一株能使发酵液的表面张力值从68 mN·m-1降低到34.5 mN·m-1,具有开发潜力,被选出作进一步的研究.该菌株经鉴定为犁头霉菌(Absidia orchidis).通过正交试验对犁头霉菌的培养条件进行优化,其优化培养条件为:植物油3.6 g·L-1,KH2PO412.1 g·L-1,Na2HPO45 g·L-1,(NH4)2SO4 1 g·L-1,NaNO32 g·L-1,酵母浸膏0.1 g·L-1,MgSO4·7H2O 0.15 g·L-1,NaCl 5 g·L-1,CaCl2 0.1 g·L-1,EDTA 1 g·L-1,KI 0.83μg·L-1,H3PO4 0.01μg·L-1,CoCl2·6H2O 0.048μg·L-1,MnSO4·H2O 0.312μg·L-1,Na2 MoO4·2H2O 0.048μg·L-1,ZnCl2 0.287μg·L-1,CuSO4·5H2O 0.125μg·L-1,初始pH值8,接种量6%.发酵70h时可获得生物表面活性剂的最大收获量,此时发酵液中生物表面活性剂的相对浓度达402倍.     

Distribution and ecological effect of mercury in Laogang landfill, Shanghai, China

Laogang landfill near Shanghai is the largest landfill in China, and receives about 10000 t of daily garbage per day, Samples of topsoil and plants were analyzed to evaluate mercury pollution from the landfill. For topsoil samples, there were significant correlations among total mercury （HgT）, combinative mercury （Hgc） and gaseous mercury （HgG）, and content of total organic carbon （TOC）, but, no significantly relationship was found between Hg content and filling time. Hg content changes in vertical profiles with time showed that the average Hgv of profiles 1992, 1996, and 2000 was similar, but their average HgG was quite different. HgT was significantly correlated with Hgc in profile 1992 and 2000, and Hgv was significantly correlated with Hg6 in profile 1996. HgG/Hgv ratio in profile samples decreased in the order of （HgG,/HgT）1992〉（HgG/HgT）1996〉〉（HgG/HgT）2000. A simple outline of Hg release in landfill could be drawn： with increasing of filling time, degradation undergoes different biodegradation, accordingly, gaseous mercury goes through small, more, and small proportion to total mercury. Distribution of Hg in plants was inhomogeneous, following the order of leaf〉root〉stem. The highest value of leaf may be associated with higher atmospheric Hg from landfill. Ligneous plants （e.g. Phyllostachys glanca, Prunus salicina and Ligustrum lucidum） are capable of enriching more Hg than herbaceous plants.     

EDTA-enhanced phytoremediation of lead contaminated soil by Bidens maximowicziana

Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.     

Decomposition of alachlor by ozonation and its mechanism

Decomposition and corresponding mechanism of alachlor, an endocrine disruptor in water by ozonation were investigated. Results showed that alachlor could not be completely mineralized by ozone alone. Many intermediates and final products were formed during the process, including aromatic compounds, aliphatic carboxylic acids, and inorganic ions. In evoluting these products, some of them with weak polarity were qualitatively identified by GC-MS. The information of inorganic ions suggested that the dechlorination was the first and the fastest step in the ozonation of alachlor.     

Enzymatic oxidation of aqueous pentachlorophenol

The influence of the nonionic surfactant Tween 80 on pentachlorophenol （PCP） oxidation catalyzed by horseradish peroxidase was studied. The surfactant was tested at concentrations below and above its critical micelle concentration （CMC）. Enhancement of PCP removal was observed at sub-CMCs. The presence of Tween 80 in the reaction mixture reduced enzyme inactivation which occurred through a combination of free radical attack and sorption by precipitated products. A simple first-order model was able to simulate time profiles for enzyme inactivation in the presence or absence of Tween 80. At supra-CMCs, the surfactant caused noticeable reductions in PCP removal, presumably through micelle partitioning of PCP which precluded the hydrophobic PCP molecule from interacting with the enzyme.     

基于综合水质标识指数和对应分析法的校园河道水质评价

以三峡大学的校园河道求索溪为研究对象,利用综合水质标识指数法确定求索溪水质类别,分析其水质时空变化规律,并利用对应分析法得出求索溪中不同监测点的主要污染因子.研究结果表明:求索溪整体的综合水质标识指数为7.423,整体水质为劣V类(地表水环境质量标准GB 3838-2002)且黑臭.从时间变化来看,求索溪4月份的水质最差,5月份次之,4、5月份所有监测点的水质都劣于V类且黑臭;8月份水质最好,水质为Ⅳ类;从空间分布来看,8个监测点综合水质标识指数均超过6.0,水质为劣V类,其中6号监测点的水质相对最好,监测点3号的水质相对最差;对应分析法得出求索溪的整体水体污染程度受总氮因子的影响最大,其次为总磷.该研究拟为求索溪及类似校园河道的水环境治理研究提供基础依据和参考.     

Effects of chitosan on growth of an aquatic plant (Hydrilla verticillata) in polluted waters with different chemical oxygen demands

Effects of chitosan on a submersed plant, Hydrilla verticillata, were investigated. Results indicated that H. venicillata could prevent ultrastructure phytotoxicities and oxidativereaction from polluted water with high chemical oxygen demand (COD). Superoxide dismutase (SOD) activity and malondialdehyde (MDA) contents in H. verticillata treated with 0.1% chitosan in wastewater increased with high COD (980 mg/L) and decreased with low COD (63 mg/L), respectively. Ultrastructural analysis showed that the stroma and grana of chloroplast basically remained normal. However, plant cells from the control experiment (untreated with chitosan) were vacuolated and the cell interval increased. The relict of protoplast moved to the center, with cells tending to disjoint. Our findings indicate that wastewater with high COD concentration can cause a substantial damage to submersed plant, nevertheless, chitosan probably could alleviate the membrane lipid peroxidization and ultrastructure phytotoxicities, and protect plant cells from stress of high COD concentration polluted water.     

Removal of cadmium using MnO2 loaded D301 resin

MnO2 loaded weak basic anion exchange resin D301 （Anion exchange resin, macroreticular weak basic styrene） as adsorbent has been prepared and applied to the removal of cadmium. The adsorption characteristics have been investigated with respect to effect of pH, equilibrium isotherms, removal kinetic data, and interference of the coexisting ions. The results indicated that the Cd^2＋ could be efficiently removed using MnO2 loaded D301 resin in the pH range of 3-8 from aqueous solutions with the co-existence of high concentration of alkali and alkaline-earth metals ions. The saturate adsorption capacity of the Cd^2＋ was 77.88 mg/g. The adsorption process followed the pseudo first-order kinetics. The equilibrium data obtained in this study accorded excellently with the Langmuir adsorption isotherm.     

Effect of coagulation pretreatment on the fouling of ultrafiltration membrane

The purpose of this study is to understand the effect and mechanism of preventing membrane fouling, by coagulation pretreatment, in terms of fractional component and molecular weight of natural organic matter （NOM）. A relatively higher molecular weight （MW） of hydrophobic compounds was responsible for a rapid decline in the ultrafiltration flux. Coagulation could effectively remove the hydrophobic organics, resulting in the increase of flux. It was found that a lower MW of neutral hydrophilic compounds, which could remove inadequately by coagulation, was responsible for the slow declining flux. The fluxes in the filtration of coagulated water and supernatant water were compared and the results showed that a lower MW of neutral hydrophilic compounds remained in the supernatant water after coagulation could be rejected by a membrane, resulting in fouling. It was also found that the coagulated flocs could absorb neutral hydrophilic compounds effectively. Therefore, with the coagulated flocs formed on the membrane surface, the flux decline could be improved.     

Penetration analysis of elements and bioleaching treatment of spent refractory for recycling

Acidithiobacillus ferrooxidans ATCC23270 and Acidithiobacillus thiooxidans TM-32 were used for bioleaching of spent refractories of aluminium and copper melting furnaces for their recycling.Firstly,penetration of elements into aluminium melting furnace refractory was investigated and it was found that up to 7 cm from surface was contaminated.Comparison on leaching efficiency by the strains ATCC23270 and TM-32 found that the strain ATCC23270 could treat larger amount of the refractories than the strain TM-32 could do.In the experiment of bioleaching of spent refractory aluminium melting furnace by the strain ATCC23270,high leaching efficiency were obtained on Al,Si,and Ca,and extremely low leaching performance was,however,shown on the rest of elements i.e.,Na,Mn,and Zn.Under the strain TM-32 use,relatively high leaching performance was recognized on Al,Si,Ca,Na,Mn,and Zn.In the experiment of bioleaching for spent refractory copper melting furnace,almost the same leaching trends were shown on Cu,Zn,Al,and Si under the strains ACTT23270 and TM-32 uses.     

Simultaneous removal of ammonium and phosphate by zeolite synthesized from coal fly ash as influenced by acid treatment

Zeolite synthesized from fly ash （ZFA） without modification is not efficient for the purification of NH4＋ and phosphate at low concentrations that occur in real effluents, despite the high potential removal capacity. To develop an effective technique to enhance the removal efficiency of ammonium and phosphate at low concentrations, ZFA was modified with acid treatment and the simultaneous removal of ammonium and phosphate in a wide range of concentration was investigated. It was seen that when compared with untreated ZFA, only the treatment by 0.01 mol/L of H2SO4 significantly improved the removal efficiency of ammonium at low initial concentrations. The behavior was well explained by the pH effect. Treatment by more concentrated H2SO4 led to the deterioration of the ZFA structure and a decrease in the cation exchange capacity. Treatment by 0.01 mol/L H2SO4 improved the removal efficiency of phosphate by ZFA at all initial P concentrations, while the treatment by concentrated H2SO4 （≥0.9 mol/L） resulted in a limited maximum phosphate immobilization capacity （PIC）. It was concluded that through a previous mild acid treatment （e.g. 0.01 mol/L of H2SO4）, ZFA can be used in the simultaneous removal of NH4＋ and P at low concentrations simulating real effluent.