微乳液介质 - 4- (6- 甲氧基 - 8- 喹啉偶氮 )- 间苯三酚分光光度法测定微量铜

研究了溴代十六烷基吡啶、正丁醇、正庚烷和水自制微乳溶液介质中,4-（6-甲氧基-8-喹啉偶氮）-间苯三酚与铜的显色反应,建立了分光光度法测定微量铜的新方法。在显色液中铜的质量浓度在0.010 mg/L～0.700 mg/L范围内符合比尔定律,方法检出限为0.003 mg/L,铝合金和水样测定的RSD为0.3%～1.7%,加标回收率为96.3%～104%。     

Simultaneous determination of selected endocrine disrupter compounds in wastewater samples in ultra trace levels using HPLC-ES-MS/MS

An analytical procedure for the simultaneous determination of six selected endocrine disrupter compounds (EDCs: diltiazem, progesterone, benzyl butyl phthalate (BBP), estrone, carbamazepine (Cbz), acetaminophen) was developed by liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ES-MS/MS). All of the parameters for HPLC and ES-MS/MS systems including mobile phase composition, flow rate, and sample injection volume were optimized to obtain not only the best separation of species interested but also low detection limits. Reverse phase chromatography coupled to ES-MS/MS was used for the separation and detection of EDCs. Formic acid (0.10% ) and 5.0 mM ammonium formate were selected as mobile phase composition in gradient elution. Detection limits for diltiazem, progesterone, BBP, estrone, Cbz, and acetaminophen were found to be 0.13, 0.12, 0.04, 0.13, 0.12, and 0.05 ng/mL, respectively. Influent and effluents from three different wastewater treatment plants located in Ankara, i.e., rotating flat-sheet membrane unit, pilot type flat-sheet membrane unit located at METU Campus and samples from Ankara central wastewater treatment plant were analyzed for their EDCs contents under the optimum conditions.     

Presence of steroid hormones and antibiotics in surface water of agricultural, suburban and mixed-use areas

The occurrence of pharmaceutically active chemicals (PACs) in the natural aquatic environment is recognized as an emerging issue due to the potential adverse effects these compounds pose to aquatic life and humans. This study presents the monitoring of two major categories of PACs in surface water: steroid hormones and antibiotics. Surface water samples were collected in the fall season from 21 locations in suburban (4), agricultural (5) and mixed (12) use suburban and agricultural areas. The water samples collected were analyzed using GC/MS for aqueous concentration of eleven steroid hormones: six natural (17alpha-estradiol, 17beta-estradiol, estrone, estriol, 17alpha-dihydroequilin, progesterone) and five synthetic (gestodene, norgestrel, levonorgestrel, medrogestone, trimegestone). In addition, 12 antibiotics (oxytetracycline, chlorotetracycline, tetracycline, sulfamethoxazole, sulfamethazine, trimethoprim, lincomycin, norfloxacin, ofloxacin, roxithromycin, erythromycin, tylosin tartrate) were analyzed using LC/MS. Steroid hormones detected in surface water were: 17alpha-estradiol, 17beta-estradiol, 17alpha-dihydroequilin, estriol, estrone, progesterone and trimegestone. Estrone had the highest detection frequency of >90% with concentrations ranging from 0.6 to 2.6 ng/l. The second most frequently detected estrogen was estriol (>80%) with concentrations ranging from 0.8 to 19 ng/l. The detection frequency varied at different sampling locations. No antibiotics were detected in the 21 streams sampled. This study aims to give a better understanding on the presence, fate and transport of PACs derived from humans and animals.     

气相色谱法测定空气和废气中8种烃类化合物

建立了针筒采样、大口径毛细管柱分离、气相色谱-氢火焰离子化检测器测定空气和废气中甲烷、乙烷、乙烯、乙炔、丙烷、异丁烷、正丁烷和正戊烷等8种烃类化合物的方法.优化了试验条件,方法线性良好,甲烷、乙烯、乙炔、乙烷、丙烷、异丁烷、正丁烷和正戊烷的检出限分别为0.09 mg/m3、0.20 mg/m3、0.18 mg/m3、0.29 mg/m3、0.28 mg/m3、0.37 mg/m3、0.16 mg/m3和0.56 mg/m3,RSD＜8.0%,加标回收率为80.5%～104%.     

Characterization of dissolved organic carbon at low levels in environmental waters by microfluidic-chip-based capillary gel electrophoresis with a laser-induced fluorescence detector

A microfluidic analytical system for characterization of dissolved organic carbon (DOC) in environmental waters, based on a capillary gel electrophoresis (CGE) device with a laser-induced fluorescence (LEF) detector, was developed. The applied voltage and the running buffer were investigated to control the simple floating injection and CGE separation for convenient cross-type microchips made from polymethylmethacylate. We obtained reproducible peaks for standard organic solutions and the determination time is less than 70 s. The values of the relative standard deviation (RSD) were 0.17–2.01% for repetitive injection (n?=?12). We demonstrated high-throughput characterization of DOC in environmental water from the Biwa Lake and the Hino River using microfluidic chip and determined that the content of DOC in the Biwa Lake changed with the seasons.     

毛细管柱气相色谱法测定环境空气中的樟脑

采用毛细管柱气相色谱氢火焰离子化检测器测定环境空气中的樟脑,选择硅胶为吸附剂,甲醇/丙酮混合溶剂(体积比90∶10)为解析剂.方法在0.544 mg/L～109 mg/L范围内线性良好,检出限为0.06 mg/L,当采样体积为20 L时,最低检出质量浓度为0.003 mg/m3,标准溶液平行测定的RSD≤3.8％,空白...     

液液萃取-高效液相色谱法测定水中四乙基铅

采用高效液相色谱紫外检测器测定水中四乙基铅,用二氯甲烷液液萃取,以甲醇/水混合溶液(体积比为95:5)为流动相,Z0RBAX Eclipse XDB-C18色谱柱分离,选择测定波长为280 nm.方法在0.100mg/L～1.00mg/L范围内线性良好,检出限和测定下限分别为0.01μg/L和0.04μg/L,水样平行...     

固相萃取-高效液相色谱法测定废水中的酚类化合物

建立了Supelclean ENVI-Chrom P柱固相萃取-高效液相色谱法测定废水中11种酚类化合物的分析方法,并对固相萃取条件和液相色谱条件进行了讨论。该方法分离效果良好,净化效果明显,方法检出限为2×10-3~2×10-2mg/L,平行分析(n=6)的RSD为2.7%~16.4%,废水加标回收率除2,4-二硝基酚偏低以外,其他化合物的回收率为61.4%~115.8%。     

On-site simultaneous determination of anions and cations in drainage water using a flow injection-capillary electrophoresis system with contactless conductivity detection

Drainage water diverted from a farm pasture, which was heavily loaded with manure, was monitored during a rain event. Concurrent anion and cation determinations at intervals of 10 min could be achieved with a new capillary electrophoresis system employing dual injection at opposite ends of the separation capillary. The flow injection approach enabled automation of the sampling process. Interruption of the separation voltage was not necessary. Contactless conductivity detection with an electrolyte solution optimized for the purpose allowed the facile simultaneous detection of the inorganic ions Cl(-), NO(3)(-), SO(4)(2-), HPO(4)(2-), NO(2)(-), NH(4)(+), K(+), Ca(2+), Na(+) and Mg(2+) and the acquisition of temporal concentration profiles of these species. The detection limits achieved were between 20 and 200 [micro sign]g l(-1) for all ions and the repeatability of peak areas and peak heights was better than 1%. The quantitative results were verified by analysing individual samples later in the laboratory with photometry and ion chromatography and the average deviations were found to be between 4 and 12%. This contribution presents a further step in the development of capillary electrophoresis towards a fully automated, low maintenance field method.     

饮用水源水中丙烯醛测定方法改进

对饮用水源水中丙烯醛的气相色谱标准测定方法作了改进,由直接进样改为吹扫捕集进样,由极性色谱柱改为中等极性色谱柱.方法在0.010 mg/L～0.100 mg/L范围内线性良好,最低检出限和检测下限分别为0.000 5 mg/L和0.002 mg/L,水样平行测定的RSD为2.8%～5.2%,平均加标回收率为90.0%～...     

固相萃取-高效液相色谱法测定水中呋喃丹、甲萘威和阿特拉津

采用固相萃取-高效液相色谱(SPE - HPLC)二极管阵列检测器同时测定水中呋喃丹、甲萘威和阿特拉津,以甲醇-水为流动相,采用梯度洗脱方式,选择220 nm为检测波长,二氯甲烷为洗脱剂.呋喃丹在0.200 mg/L ～5.00 mg/L、甲萘威和阿特拉津在0.020 mg/L～5.00 mg/L范围内线性良好,检出限...     

固相萃取-气相色谱法测定饮用水中甲基汞

根据巯基棉在一定酸性条件下能定量吸附甲基汞的原理,利用多通道并联的固相萃取装置,采用气相色谱(ECD)方法测定饮用水中痕量甲基汞,考察了水样pH值对回收率的影响.方法在0.050 mg/L～1.00 mg/L范围内线性良好,当采样体积为1.0 L时,检出限为0.03 ng/L,标准样品与实际水样平行测定的相对标准偏差均...     

固相萃取-气相色谱/质谱法测定地下水中15种农药残留

通过优选色谱柱,进一步改进色谱分离条件,优化前处理方法,建立一种快速高效测定地下水中15种农药残留量的GC-MS方法。该法采用分段法选择离子(SIM)扫描,具有更高的灵敏度、较低的检出限和较高的回收率,检出限低于0.004 8μg/L,回收率为85.9%~107.4%。本方法的突出特点是前处理速度快、萃取溶剂用量少、环境污染小、色谱运行时间短,基本稳定在25 min内完成分析,适用于大批量样品检测。     

Dissipation and residue of MCPA (4-chloro-2-ethylphenoxyacetate) in wheat and soil

A rapid and simple HPLC method has been developed for the quantitation of 4-chloro-2-methylphenoxyacetic acid (MCPA) in both wheat and soil samples. Samples were extracted in acidic media and cleaned up by solid-phase extraction with C(18) cartridges before HPLC-DAD detection. The limits of detection and quantification of MCPA were 0.02 ng and 0.01 mg/kg for both wheat and soil. The mean recoveries ranged from 87.1% to 98.2%, and the RSDs ranged from 0.604% to 3.44% for the three spiked levels (0.01, 0.1, 0.5 mg/kg). The proposed method was successfully applied to the analysis of MCPA residues in wheat and soil samples from an experimental field. The dissipation half-lives in soil were calculated to be 3.22 days (Beijing) and 3.10 days (Tianjin), respectively. Direct confirmation of the analytes in real samples was achieved by gas chromatography-mass spectrometry. The results indicated that at harvest time, the residues of MCPA in wheat were well below the maximum residue levels and were safe to apply in wheat.     

气相色谱法测定土壤中37种有机磷农药残留

采用气相色谱法测定土壤中37种有机磷农药,当取样量为10 g时,37种有机磷农药方法检出限为0. 002～0. 015 mg/kg,测定下限为0. 008～0. 060 mg/kg。低含量加标样品中有机磷农药的加标回收率为72. 8%～104%,相对标准偏差为4. 2%～13. 8%;中含量加标样品中有机磷农药的加标回收率为71. 5%～101%,相对标准偏差为4. 3%～13. 5%;高含量加标样品中有机磷农药的加标回收率为74. 6%～109%,相对标准偏差为6. 8%～14. 6%。该方法灵敏度高、分离效果好、重现性好,能够满足土壤中37种有机磷农药残留检测的要求。     

离子色谱法测定地表水中总氮

采用碱性过硫酸钾消解水样，OnGuardⅡBa柱萃取、过滤，去除消解液中大量硫酸盐，离子色谱法测定地表水中总氮含量。试验表明，方法在0ms／L～20．0mg／L之间线性良好，相关系数r为0．9994，方法检出限为0．007mg／L。该方法与国标法同时测定标准物质，测定值均在定值范围内，6次平行测定结果的RSD分别为2．3％和1．8％，地表水样的加标回收率为95．7％～105％。实际水样的测定结果与国标法比对，无明显差异。     

同步荧光光谱法测定环境水样中的多环芳烃

为了建立快速测定水体中多环芳烃的方法,用恒波长同步荧光法对14种多环芳烃混合标样进行了分析。在优化的实验条件下,对环境水样进行分析,可以鉴别出11种多环芳烃。14种PAHs在0～1000ng/ml范围内呈良好的线性关系,相关系数r均不小于0.9988,相对标准偏差(RSD)在1.06%～1.67%之间(n=6)。14种PAHs的检出限在0.072～3.9ng/ml之间。该方法应用于污水、样河水样、池塘水样中的多环芳烃检测取得了良好的效果,回收率分别为82.2%～111.0%、86.0%～107.0%、88.0%～106.2%(n=5)。     

A remote in situ monitor based on continuous flow analysis for the quantitation of sub-micromolar levels of hexavalent chromium in natural waters

We describe the design, optimization, and application of a small, lightweight, deployable monitoring instrument for accurately measuring parts-per-billion levels of hexavalent Cr in surface waters at hourly intervals. The monitor quantifies Cr(vi) using a standard molecular absorbance spectroscopic method, i.e. by formation of a complex with 1,5-diphenylcarbazide (DPC). The continuous flow analysis (CFA) design uses narrow conduits (0.90 mm) that are hot-forged onto poly(methyl methacrylate) ('Plexiglas') plates based on the method of Jannasch et al.(Anal. Chem., 1994, 66, 3352). The sample stream is drawn through the manifold at 25 microl min(-1) using a mini-peristaltic pump; osmotic pumps (10 microl h(-1)) are used to continuously inject reagent (2.0 mM DPC, 0.60 M HNO(3), 5.0% w/v acetone, and 0.10% w/v Brij-35) and to periodically introduce quality control standards and a cleaning solution (0.50 M HNO(3)). The 'Z-type' optical cell uses a liquid-core waveguide (10 mm) to collimate the light-emitting diode source beam (lambda(max) 574 nm) to a broadband photodiode detector. Figures of merit are: 7 min cycle time, response within 28 min and clear-down within 31 min, low waste generation (<40 ml d(-1)), detection limit (3sigma) of 48.4 microg l(-1) as Cr(vi) or 0.411 microM as chromic acid, 1.54% relative standard deviation at 100 microg l(-1), and selectivity for dissolved Cr(vi) in authentic surface water samples containing moderate levels (>0.21% w/v) of total particulate matter. Using a test chamber containing Milwaukee Harbor water that was periodically fortified with Cr(vi) standards, continuous testing over a 15 day period (354 h) yielded results that were in excellent agreement (<5% variation) with measurements made using an ICP-MS reference method. Drift in the calibration model over the test period was 1.23% and the variation in a 0.50 mg l(-1) Cr(vi) standard was 3.8%(n= 11). Known interferences to the DPC chemistry (Mo, V, and Hg at >5 mg l(-1)) were undetected in the harbor water by ICP-MS.     

离子色谱法-抑制型电导检测城市污水中的高氯酸根

利用离子色谱法-抑制型电导检测了城市污水中的持久污染物高氯酸根,以IonPac AS20高容量强亲水阴离子交换柱分离,NaOH流动相等度淋洗,高氯酸根在12min内出峰。高氯酸根在0.01~50 mg/L内具有良好的线性,相关系数为0.9998,50μl进样时检出限可达到3μg/L。方法可用于多种城市污水中高氯酸根的监测,样品测定的标准相对偏差在0.60%~0.94%之间,加标回收率在97.3%~105.8%之间,具有较好的准确性和重现性。     

Determination of trace transition metals in environmental matrices by chelation ion chromatography

Trace transition metals (Fe^3?+?, Mn, Cu, Cd, Co, Zn, Ni) in environmental samples were analyzed by chelation ion chromatography using a mixed bed ion-exchange column with pyridine-2,6-dicarboxylic acid (PDCA) and oxalic acid as eluent and large volume direct injection (1,000 ??l). The two eluents, PDCA and oxalic acid, were tested, and repeatability and detection limits were compared. The total analysis time was ~15 min. The separation with PDCA was more successful than that obtained with acid oxalic. It was observed that utilizing PDCA resulted in lower detection limits, higher repeatability, and a quantitative detection of Cd and Mn, which coelute as a single peak when using the oxalic acid. At last, the PDCA calibration graphs resulted linear (r ²?>?0.999) in the range 0.4?C1,000 ??g/L. The procedure was applied to the analysis of metals in soils and in water samples. The results obtained from the analysis of natural waters have demonstrated that the method is simple and efficient, therefore, can be used for the determination of metals in natural waters using a continuous and automatic monitoring system.