TiO2 nanotubes as solid-phase extraction adsorbent for the determination of polycyclic aromatic hydrocarbons in environmental water samples

An analytical method based on TiO2 nanotubes solid-phase extraction (SPE) combined with gas chromatography (GC) was established for the analysis of seven polycyclic aromatic hydrocarbons (PAHs): acenaphtylene, acenaphthene, anthracene, fluorene, phenanthrene, fluoranthene and pyrene. Factors a ecting the extraction e ciency including the eluent type and its volume, adsorbent amount, sample volume, sample pH and sample flow rate were optimized. The characteristic data of analytical performance were determined to investigate the sensitivity and precision of the method. Under the optimized extraction conditions, the method showed good linearity in the range of 0.01–0.8 g/mL, repeatability of the extraction (RSD were between 6.7% and 13.5%, n = 5) and satisfactory detection limits (0.017–0.059 ng/mL). The developed method was successfully applied to the analysis of surface water (tap, river and dam) samples. The recoveries of PAHs spiked in environmental water samples ranged from 90% to 100%. All the results indicated the potential application of titanate nanotubes as solid-phase extraction adsorbents to pre-treat water samples.     

固相萃取—气相色谱法测定海水中的666、DDT

采用固相萃取技术富集海水中的666、DDT,并使用气相色谱进行测定。主要包括不同填料(C8、C18、C18-N)、SPE柱规格(500 mg/3 mL、500 mg/6 mL)、洗脱试剂、上样流速、水样pH和洗脱试剂体积6个因素对666、DDT富集效率的影响。最终确定最优条件为:采用500 mg/6 mL C18SPE小柱,调节海水pH=6,上样流速4~5mL/min,10 mL二氯甲烷洗脱。优化后的固相萃取-气相色谱方法测定海水中666、DDT加标10 ng/L回收率为75.7%~110.4%,精密度为1.16%~4.00%,方法检出限为0.19~1.20 ng/L。     

Optimization of enrichment processes of pentachlorophenol (PCP) from water samples

The method of enriching PCP( pentachlorophenol ) from aquatic environment by solid phase extraction (SPE) was studied.Several factors affecting the recoveries of PCP, including sample pH, eluting solvent, eluting volume and flow rate of water sample, were optimized by orthogonal array design(OAD). The optimized results were sample pH 4; eluting solvent, 100% methanol; eluting solvent volume, 2 ml and flow rate of water sample, 4 ml/min. A comparison is made between SPE and liquid-liquid extraction(LLE) method. The recoveries of PCP were in the range of 87.6%-133.6% and 79%-120.3% for SPE and LLE, respectively. Important advantages of the SPE compared with the LLE include the short extraction time and reduced consumption of organic solvents. SPE can replace LLE for isolating and concentrating PCP from water samples.     

活性炭纤维萃取浓缩水样中微量有机磷农药

采用活性炭纤维(ACF)为固相萃取剂填料,萃取测定水样中微量有机磷农药。研究分析了ACF用量、洗脱剂类型、农药初始质量浓度、水样过柱速度及pH等因素对萃取回收率的影响。结果表明:洗脱剂类型和ACF用量是显著的影响因素。最佳萃取条件为:含0 1μg L有机磷农药的1L加标水样,需0 2gACF和8mL二氯甲烷,水样过柱速度40mL min。pH对萃取影响不大。萃取回收率为80 7%～118%。      

基于固相萃取的水中多种有毒有害有机污染物富集方法优化

以降低固相萃取杂质、提高目标化合物的回收率为目的,提出了一种基于固相萃取的水中多种有毒有害有机污染物富集方法.用丙酮和二氯甲烷等溶剂洗脱未上样的固相萃取柱,评价了固相萃取各个环节对正构烷烃、酞酸酯等杂质浓度的贡献值,发现85%杂质来自填料的溶出物(以Waters Oasis HLB为例).填料经二氯甲烷、丙酮、甲醇依次索氏提取24 h后,填料的溶出物明显减少,气相色谱图中杂质峰的数量和强度均明显降低.比较了6种常用固相萃取填料在索氏提取后对lgKow1.46～8.1之间的农药、多环芳烃、酚、酞酸酯等40种目标化合物的回收率,发现Waters Oasis HLB在改性聚苯乙烯-二乙烯基苯填料中回收率最高,平均为77%;Waters SepPak AC-2在活性炭填料中回收率最高,对农药的平均回收率为74%.WatersOasis HLB和Waters SepPak AC-2固相萃取柱串联后,目标化合物的回收率明显提高,平均为87%.     

Determination of haloacetic acids in hospital e uent after chlorination by ion chromatography

The ion chromatography combined solid phase extraction （SPE） method was developed for the analysis of low concentration haloacetic acids （HAAs）, a class of disinfection by-products formed from chlorination of hospital wastewater. The monitored HAAs included monochloroacetic acid, monobromoacetic acid, dichloroacetic acid, dibromoacetic acid and trichloroacetic acid. The method employed a sodium hydroxide eluent at a flow rate of 0.8 ml/min, electrolytically generated gradients, and suppressed conductivity detection. To analyze the HAAs in real hospital wastewater samples, C18 pretreatment cartridge was utilized to reduce samples＇ turbidity. Preconcentration with SPE and matrix elimination with treatment cartridges were investigated and found to be able to obtain acceptable detection limits. Linearity, repeatability and detection limits of the above method were evaluated. The detection limits of monobromoacetic acid and dibromoacetic acid were 2.61 μg/L and 1.30 μg/L, respectively, and the other three acids are ranging from 0.48 to 0.82μg/L under 25-fold preconcentration. When the above optimization procedure was applied to three hospital wastewater samples with different treatment processes in Tianjin, it was found that the dichloroacetic acid was the major compound, and the growth ratios of the HAAs after disinfection by sodium hypochlorite were 91.28%, 63.61% and 79.50%, respectively.     

焦化废水中痕量苯并(a)芘的固相萃取和GC-MS检测方法

基于固相萃取(SPE)和气相色谱/质谱联用技术(GC-MS),建立了一种焦化废水中痕量苯并(a)芘(BaP)的定量分析方法。BaP水样添加甲醇改性后经SPE富集净化、二氯甲烷洗脱、氮吹浓缩、二氯甲烷或乙腈定容后采用GC-MS进行定量分析。结果表明:在优化的样品前处理和分析条件下,BaP标准曲线的线性相关系数R2>0.99,方法回收率为79.6%~85.5%,方法检出限和定量限分别为4.33 ng/L和14.45 ng/L。该方法应用于内蒙古某焦化厂二级生化出水加标样品中BaP的测定,得到BaP的回收率为83.3%~89.3%,表明其灵敏度高、选择性好,适用于焦化废水中痕量BaP的定量检测。     

利用两种采样技术监测淮河水中的有毒有机污染物

利用固相萃取（SPE）和三油酸酯－半渗透膜采样器（triolein－SPMD）采集并测定了淮河信阳、淮南２个采样点水样中有毒有机污染物浓度．对２种采样方法的比较发现,对于水中多氯联苯、多环芳烃、取代苯３类目标污染物检出种类基本相同,但这些污染物在SPMD样品中浓度的富集倍数明显增加．污染物在triolein－SPMD酯中的高浓度,便污染物的定性和定量更加容易和准确,可以根据triolein－SPMD酯／水分配平衡理论计算目标污染物在水中的平均浓度,其结果与SPE具有可比性．综合triolein－SPMD在经济和操作上的诸多优点,本研究认为triolein－SPMD技术可在我国的优先污染物的监测工作中发挥作用．     

SPE-GC-MS/SIM测定水节霉发生地河水中半挥发性有机物

为测定水节霉发生地河水中ρ(SVOCs)(SVOCs为半挥发性有机物),比较了LLE(液液萃取)和SPE(固相萃取)前处理法提取加标空白水样中ρ(SVOCs)的GC-MS/SIM测定结果,确定并采用重现性好的SPE-GC-MS/SIM法测定了水节霉发生地河水中的ρ(SVOCs). 结果表明,LLE和SPE法对SVOCs的加标回收率分别为41.8%~121.5%和31.5%~124.4%,相对标准偏差分别为6.0%~18.0%和0.9%~14.5%,二者回收率相差不大,但SPE法的相对标准偏差小于LLE法,SPE法重现性较好,因此采用SPE-GC-MS/SIM法测定2011年2月水节霉发生地河水中的ρ(SVOCs),共检出29种SVOCs,其中ρ(邻苯二甲酸二乙酯)、ρ(∑PAHs)、ρ(硝基苯)、ρ(1,2-二氯苯)和ρ(1,4-二氯苯)分别为1 020.59、532.14、43.39、38.52和19.57 ng/L,均未超出GB 5749—2006《生活饮用水卫生标准》相关限值,表明水节霉发生地未发生SVOCs污染.      

关于固相萃取技术富集水中苯系物的探讨

苯系物尤其是苯、甲苯和二甲苯作为重要溶剂和基本化工原料,被广泛应用于油漆、农药、医药、有机化工等行业,由此而产生的废水、废气便成为河流、空气和地下饮用水等有机污染物的重要来源。除苯是已知的致癌物以外,其它几种化合物对人体和水生生物均有不同程度的毒性。在我国水环境中优先控制污染物黑名单中,苯、甲苯、乙苯及二甲苯的三种异构体均榜上有名。因此,测定水中苯系物含量对环境保护具有重要的意义。本文基于固相萃取（SPE）技术富集水样中苯系物的思路,选择苯、甲苯、乙苯、对二甲苯、邻二甲苯、苯乙烯和异丙苯作为目标化合物,对C18键合相吸附剂富集水中苯系物的吸附和脱附过程的参数优化进行了研究,为建立一种简便、高效的水中苯系物的检测方法提供了依据。     

液相色谱质谱法测定水体及土壤中的类固醇激素

建立了水体和土壤中类固醇激素的液相色谱质谱分析方法。水样采用固相萃取方法富集,土壤样经加速溶剂萃取后由固相萃取净化和富集。处理好的样品经丹磺酰衍生化后上仪器分析。结果表明,类固醇激素在水体和土壤中的检出限分别为0.01~0.6ng/L和0.01~0.19ng/g,回收率分别为77%~97%和62%~119%,RSD小于6.04%和15.5%。该方法具有较高的准确度和精密度,适用于环境水体及土壤中类固醇激素残留的分析。     

固相萃取和高效液相色谱联用测定污水中的五氯苯酚

采用固相萃取和高效液相色谱相结合的方法对污水中五氯苯酚的含量进行定量检测。结果表明,污水的pH值为4,流速控制在4mL/L以内,C18固相萃取柱对五氯苯酚有良好的吸附保留性能,以2mL的甲醇洗脱,洗脱效率在85%~95%之间。与传统的液液萃取相比,固相萃取的优势在于操作时间缩短、有机溶剂的使用量减少。     

固相萃取-气相色谱法快速分析水中硝基苯类化合物

建立了固相萃取-气相色谱定量分析水中硝基苯类化合物的分析方法,详尽地叙述了水样预处理过程.对固相萃取,水样预处理和色谱分离条件做了试验并予以优化.采用ODS-C18固相萃取柱将样品浓缩富集后,以DB-17色谱柱(30 m×0.32 mm×0.25 μm)为分离柱,以ECD和FID检测.方法检出限在0.12～90 μg/...     

Detection of geosmin and 2-methylisoborneol by liquid-liquid extraction-gas chromatograph mass spectrum (LLE-GCMS)and solid phase extraction-gas chromatograph mass spectrum (SPE-GCMS)

Two sample preparation methods were introduced and compared in this paper to establish a simple, quick and exact analysis of geosmin and 2-methylisoborneol. LC-18 column was employed in solid phase extraction (SPE), 1.0 mL of hexane was adopted in liquid-liquid extraction (LLE), and the extracts were analyzed by gas chromatograph mass spectrum (GCMS) in selected ion mode. Mean recoveries of SPE were low for 2-methylisoborneol (2-MIB) and geosmin (GSM) with values below 50%. For LLE, the recoveries were satisfyingly above 50% for 2-MIB and 80% for GSM. Detection limits of the LLE method were as low as 1.0 ng/L for GSM and 5.0 ng/L for 2-MIB. A year-long investigation on odor chemicals of drinking water in Shanghai demonstrated that in the summer, there was a serious odor problem induced by a high concentration of 2-MIB. The highest concentration of 152.82 ng/L appeared in July in raw water, while GSM flocculation was minimal with concentrations below odor threshold.     

水中毒死蜱的固相萃取气相色谱测定法

建立水中毒死蜱的固相萃取——气相色谱FPD测定法。本方法的线性范围为0.25～5.00mg/L,回收率为94.2%,RSD为2.5%,检出限为0.25μg/L。该方法灵敏、准确,能很好地排除干扰,可满足水中痕量毒死蜱的测定。     

分散固相萃取-超高效液相色谱串联质谱法同时测定水产品中4种PPCPs

建立了分散固相萃取-超高效液相色谱串联质谱（dSPE-UPLC-MS/MS）测定水产品中磺胺甲基异恶唑（SMZ）、甲氧苄啶（TMP）、泰乐菌素（TYL）和三氯卡班（TCC）等两类4种PPCPs残留的分析方法。样品经乙腈提取,中性氧化铝吸附剂快速分散固相萃取净化,水浴条件下氮气吹干,20%乙腈-5 mM乙酸铵水溶液（含0.1%甲酸）溶解,离心过膜,上机检测。以乙腈和5 mM乙酸铵（含0.1%甲酸）作为流动相,Waters BEH C₁₈色谱柱梯度洗脱分离,分时段多反应监测模式下同时定量和定性分析。采用空白基质匹配标准法定量,各种药物在相应的质量浓度范围内线性关系良好,相关系数（r2）大于0.9984;方法的检测限和定量下限分别为0.1×10-9~1.0×10-9和0.2×10-9~2.0×10-9;样品的平均加标回收率为71.8%~96.5%,相对标准偏差小于9.8%。该方法操作简便快速、灵敏、可靠,适用于水产样品中4种PPCPs的测定。     

长江南京段水体中7种苯胺类化合物的检测方法及生态风险评价

应用固相萃取结合高效液相色谱-串联质谱法,建立了同时测定环境水样中7种苯胺类化合物的检测方法.实验表明,以ZORBAX Eclipse Plus C18 (3.5μm,2.1×150mm)色谱柱为分离柱,乙腈-水(2mmol/L甲酸铵)为梯度洗脱的流动相,在电喷雾质谱正离子模式下,7min内可以分离目标化合物;在1~200μg/L浓度范围内,7种苯胺类化合物的峰面积与质量浓度的线性关系良好;添加水平分别为0.8、4.0、20.0mg/L时,目标化合物的平均回收率分别为68.5%~102.2%、71.4%~89.4%、62.0%~78.3%,相对标准偏差均小于6.9%;利用本方法对长江南京段平水期(2014.4)、丰水期(2014.8)和枯水期(2014.12)的14个采样点的环境水样进行检测,检出4-硝基苯胺、2,6-二乙基苯胺、3,4-二氯苯胺和4-异丙基苯胺4种苯胺类化合物,且4-硝基苯胺在3个时期14个采样点均能检出;风险商值法评估长江南京段水体中4-硝基苯胺的生态风险为低生态风险.     

固相萃取-气相色谱/质谱法同时测定海水中9种硝基苯类化合物

建立了固相萃取-气相色谱/质谱(GC/MS)同时测定海水中9种硝基苯类化合物的分析方法。海水样品经Oa-sisHLB固相萃取小柱萃取富集,正己烷/丙酮洗脱,采用GC/MS进行定性定量,线性响应良好,基体干扰小,方法检出限在0.03～0.10μg/L(按采样1 L水计),添加回收率在72.8%～116%,精密度为1.2%～5.4%,并利用该方法对广西近岸海域6个点位实际海水样品进行了监测。该方法可以同时满足海水中9种硝基苯类化合物的测定。     

Determination of haloacetic acids concentrations in hospital effluent after chlorination by ion chromatography

The ion chromatography combined solid phase extraction (SPE) method was developed for the analysis of low concentration haloacetic acids(HAAs),a calss of disinfection by-products formed as a result of chlorination of hospital wastewater. The monitored HAAs included monochloroacetic acid, monobromoacetic acid, dichloroacetic acid, dibromoacetic acid and trichloroacetic acid. The method employed a sodium hydroxide eluent at a flow rate of 0.8 ml/min, electrolytically generated gradients, and suppressed conductivity detection. To analyze the HAAs in real hospital wastewater samples, C18 pretreatment cartridge was utilized to reduce samples' turbidity. Preconcentration with SPE and matrix elimination with treatment cartridges were investigated and were found to be able to obtain acceptable detection limits. Linearity, repeatability and detection limits of the above method were evaluated. The detection limits of monobromoacetic acid and dibromoacetic acid were 2.61 μg/L and 1.30 μg/L respectively, and the other three are ranging from 0.48 to 0.82 μg/L under 25-fold preconcentration. When the above optimization procedure was applied to three hospital wastewater samples with different treatment processes in Tianjin, it was found that the dichloroacetic acid is the major compound, and the growth ratios of the HAAs after disinfection by sodium hypochlorite were 91.28%, 63.61% and 79.50%, respectively.     

固相萃取技术在环境水质监测方法开发中的应用

固相萃取技术非常适用于环境水质中痕量有机污染物的监测分析。文章从选择固相萃取柱到萃取液进入色谱分析这样一个完整的过程,并以使用该技术萃取环境水样中的硝基苯类化合物为例,具体阐述了如何使用固相萃取技术建立一个方便实用的环境水质监测分析方法。