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1.
丁宗庆  张琼瑶  刘光东 《化学学报》2009,67(17):1962-1966
研究了分散液液微萃取-数码比色法测定水样中的痕量钒. 在酸性介质中, 痕量钒(V)和N-苯甲酰-N-苯基羟胺(BPHA)作用, 生成紫红色螯合物, 用乙醇做分散剂, 以三氯甲烷为萃取剂进行分散液液微萃取, 萃取液点样在薄层硅胶板上用数码相机进行数码成像. 成像斑点的灰度值和钒(V)的浓度成正比, 据此建立了测定水样中痕量钒的新方法. 对影响萃取富集效率和数码成像效果的因素进行了优化. 钒(V)浓度在5.0~400 μg•L-1范围内有良好的线性关系(r=0.9993), 检出限为0.87 μg•L-1. 方法已应用于实际水样分析, 加标回收率在97.4%~102.7%之间, 相对标准偏差在1.7%~3.3%之间. 方法具有仪器成本低、方便快速、灵敏度高、环境友好等特点, 可满足野外现场的检测要求.  相似文献   

2.
采用凝固-漂浮分散液液微萃取(SFO-DLLME)-高效液相色谱法测定水样中3种氯酚.以密度小于水,且凝固点为24 ℃的1-十二醇为萃取剂,甲醇为分散剂,对水样进行分散液液微萃取.将混合液离心,再通过冷冻凝固操作使漂浮的萃取剂和水相分离,萃取剂复溶后进样测定.本实验确定的最佳实验条件为:萃取剂200 μL、分散剂300 μL、1.2 g NaCl、1 mol/L H3PO4 200 μL、样品体积8.0 mL、萃取时间3 min.3种氯酚测定的线性范围为0.05~6.0 mg/L;检出限为20~38 μg/L.应用本方法分析实际水样,加标回收率在90.11%~107.7%之间;日间相对标准偏差在3.5%~4.6%之间.本方法扩展了分散液液微萃取萃取剂的选择范围,具有简便、快速、准确、环境友好等特点.  相似文献   

3.
研究了凝固-漂浮分散液液微萃取(SFO-DLLME)-分光光度法测定水样中痕量亚硝酸根的方法。以1-十二醇为萃取剂,乙醇为分散剂进行分散液液微萃取,离心后通过冷冻凝固操作使漂浮的萃取剂和水相分离。最佳实验条件下,方法的线性范围为2.0~280μg/L(r=0.999 9),检出限为0.34μg/L。方法已成功应用于环境水样分析,相对标准偏差在2.4%~3.3%,加标回收率在98.2%~102.4%。  相似文献   

4.
建立了分散液液微萃取-柱前衍生-高效液相色谱法测定水样中双酚A的分析方法.通过交互正交试验和混合型优化实验设计对影响因素(萃取剂体积、分散剂类型及其体积、水样体积、pH值及离子强度)进行了优化.优化后的分散液液微萃取条件为:60 μL萃取剂,0.4 mL分散剂(甲醇),pH 4.0;优化后的柱前衍生化条件:0.1 mL 2.0 g/L衍生剂(对硝基苯甲酰氯)、衍生化时间30 min;方法的线性范围:0.002~0.2 mg/L(r=0.9997),检出限0.007 μg/L(S/N=3);不同浓度双酚A的萃取率为59.0%~63.0%,相对标准偏差(RSD)2.5%~9.2%(n=5);水样中双酚A的加标率为86.5%~107.1%,RSD为4.0%~11.9%(n=5),其它雌激素(雌酮、雌二醇、雌三醇和17α-乙炔基雌二醇)对双酚A的测定无干扰.本方法可以对水环境中的痕量BPA进行检测,具有操作简便、快速等优点.  相似文献   

5.
用分散液液微萃取-气相色谱/质谱法测定水样中的16种多环芳烃(PAHs)。通过实验确定最佳萃取条件为:20μL四氯化碳作萃取剂,1.0 mL乙腈作分散剂,超声萃取1 min。在优化条件下,多环芳烃的富集倍数达到216~511,方法在0.05~50μg/L范围内呈良好的线性关系,相关系数(R2)在0.9873~0.9983之间,检出限为0.0020~0.14μg/L。相对标准偏差(RSD)在3.82%~12.45%(n=6)之间。该方法成功用于实际水样中痕量多环芳烃的测定。  相似文献   

6.
分散液液微萃取-气相色谱法测定水样中甲基环硅氧烷   总被引:1,自引:0,他引:1  
将分散液液微萃取与气相色谱法技术相结合,建立了测定水样中3种甲基环硅氧烷残留的方法.重点探讨了萃取剂的种类和用量、分散剂的种类和用量、萃取时间及盐浓度等对样品萃取效率的影响.结果表明在优化条件下,待测物在5~100μg/L范围内线性良好(r>0.99),检出限在2~4μg/L之间,富集倍数可达165~170倍,相对标准...  相似文献   

7.
张建华  黄颖  陈晓秋  陈金花  李辉  陈国南 《色谱》2009,27(6):799-803
建立了简便、快速、有效的分散液-液微萃取-高效液相色谱-荧光检测(DLLME-HPLC-FLD)测定环境水样中15种多环芳烃(PAHs)的方法。重点探讨了萃取剂的种类和用量、分散剂的种类和用量以及萃取时间等对PAHs萃取效率的影响。在优化的条件下,评价了方法的可靠性。15种PAHs在0.01~10 μg/L范围内呈良好的线性关系,相关系数r均不小于0.9913,峰面积的相对标准偏差(RSD)在2.3%~4.7%之间(n=6)。在优化条件下,富集因子和萃取回收率良好,分别为674~1032和67.4%~103.2%,15种PAHs的检出限(S/N=3)在0.0003~0.002 μg/L之间。建立的方法应用于敖江水样中PAHs的检测,平均加标回收率在79.5%~92.3%之间,RSD在4.3%~6.7%范围内(n=5)。该方法适用于环境水样中痕量PAHs的分析。  相似文献   

8.
分散液-液微萃取/高效液相色谱法测定水样中的痕量双酚A   总被引:4,自引:0,他引:4  
建立了分散液-液微萃取与高效液相色谱联用技术测定水样中痕量双酚A(BPA)的方法. 通过对实验条件的筛选及优化, 得到最佳条件: 22.5 μL氯苯作萃取剂、0.5 mL丙酮作分散剂、0 min静止萃取时间、调节pH 3.2左右、10%离子强度及9 mL水样体积. 此条件下方法的线性范围为0.5~100 μg/L(R2=0.9941), 检出限为0.10 μg/L. 在BPA质量浓度为1 μg/L条件下, 方法回收率为87.8%~111.0%, 相对标准偏差8.3%(n=5), 富集倍数范围1905~2527. 对添加不同BPA浓度的自来水、地表水及回用中水进行分析, 回收率分别为(108±11.1)%, (107±13.2)%及(81.2±6.2)%(n=3). 在既定的色谱条件下, BPA的测定不受乙炔基雌二醇、雌二醇、雌三醇、雌酮和壬基酚等雌激素的干扰.  相似文献   

9.
建立了基于空气辅助溶剂去乳化-分散液液微萃取(AA-SD-DLLME)-数字成像比色法(DIC)快速测定水环境中六价铬的新方法。自制的一次性塑料滴管中加入样品,在硫酸介质中六价铬与二苯碳酰二肼、十二烷基硫酸钠反应生成紫红色的三元络合物。以轻质溶剂正己醇作为萃取剂,采用空气辅助-分散液液微萃取方法对该络合物进行萃取获得乳化体系,然后加入去乳化剂甲醇破坏乳化体系,无需离心步骤即可使两相分离;取出滴管窄端上层富集的萃取层到离心管中,可通过数字成像比色装置对六价铬进行比色测定。优化了显色剂浓度、十二烷基硫酸钠浓度、pH、萃取剂种类及用量、萃取混匀次数、去乳化剂种类及用量等条件。在优化实验条件下,方法的线性范围为10~150μg/L,相关系数(R2)为0.9989,检出限为2μg/L,加标回收率为92.3%~110.3%,相对标准偏差(RSD)为1.3%~2.0%(n=10)。该方法具有较高的灵敏度、较好的准确性,能现场快速测定环境水样中六价铬。  相似文献   

10.
以离子液体([Omim][PF6])为萃取剂,采用冷诱导分散液-液微萃取对环境水样中的己烯雌酚和双烯雌酚残留进行富集.优化后的萃取条件:在pH 3.0的条件下,以50 μL离子液体为萃取剂,0.8 mL甲醇为分散剂,采用反相 Extend-C18柱(5 μm, 250 mm×4.6 mm),流动相为水-甲醇(体积比40 ∶ 60),流速:1.0 mL/min,柱温:35 ℃,检测波长:245 nm.在优化的萃取条件下,己烯雌酚和双烯雌酚的线性范围均为2.5 ~200 μg/L,检出限(S/N=3)为80 ng/L.应用于环境水样中己烯雌酚和双烯雌酚的检测,加标回收率为93% ~98%,相对标准偏差为3.0% ~5.4%,建立的方法简单、环保.  相似文献   

11.
施艺玮  张宁  操雯  洪战英 《色谱》2020,38(5):491-501
分散液液微萃取是一种新型微萃取技术,具有易操作、低成本、耗时短、环境友好、萃取效率高等优点。该文着眼于分散液液微萃取技术中萃取剂的性质及辅助分散方式,综述了常规分散液液微萃取、离子液体分散液液微萃取、超声辅助分散液液微萃取等多种萃取模式,并重点归纳总结了近5年分散液液微萃取技术在生物样品分析领域的应用进展。  相似文献   

12.
In this article, dispersive liquid-liquid microextraction (DLLME), based on the use of so-called switchable polarity dispersive solvent (SPDS) for microextraction, is presented for the first time. The new extraction technique makes use of a mixture of extraction solvent (dichloromethane) and the SPDS (acrylic acid). This mixture is injected into the aqueous sample solution, which was previously fortified with the alkaline agent (NaOH). The SPDS is dissolved in aqueous phase and a cloudy solution consisting of fine droplets of extraction solvent fully dispersed in the aqueous phase is observed. Simultaneously, as a consequence of the fast neutralization reaction, the SPDS investigated is converted into water-soluble salt and phase separation is achieved because the SPDS switches its polarity. Conversion of the SPDS excludes the negative influence of the conventional dispersive solvents used in DLLME on the solubility of target analytes in aqueous phase and, as a result, increases the DLLME efficiency.  相似文献   

13.
A new simple and reliable method combining an acetonitrile partitioning extractive procedure followed by dispersive solid-phase cleanup (QuEChERS) with dispersive liquid–liquid microextraction (DLLME) and further gas chromatography mass spectrometry analysis was developed for the simultaneous determination of bisphenol A (BPA) and bisphenol B (BPB) in canned seafood samples. Besides the great enrichment factor provided, the final DLLME extractive step was designed in order to allow the simultaneous acetylation of the compounds required for their gas chromatographic analysis. Tetrachloroethylene was used as extractive solvent, while the acetonitrile extract obtained from QuEChERS was used as dispersive solvent, and anhydride acetic as derivatizing reagent. The main factors influencing QuEChERS and DLLME efficiency including nature of QuEChERS dispersive-SPE sorbents, amount of DLLME extractive and dispersive solvents and nature and amount of derivatizing reagent were evaluated. DLLME procedure provides an effective enrichment of the extract, allowing the required sensitivity even using a single quadropole MS as detector. The optimized method showed to be accurate (>68?% recovery), reproducible (<21?% relative standard deviation) and sensitive for the target analytes (method detection limits of 0.2?μg/kg for BPA and 0.4?μg/kg for BPB). The screening of several canned seafood samples commercialized in Portugal (total?=?47) revealed the presence of BPA in more than 83?% of the samples with levels ranging from 1.0 to 99.9?μg/kg, while BPB was found in only one sample at a level of 21.8?μg/kg.  相似文献   

14.
采用分散液相微萃取与气相色谱-电子捕获检测联用技术建立了测定葡萄样品中百菌清、克菌丹和灭菌丹农药残留的新方法.对影响萃取和富集效率的因素进行了优化.萃取条件选定为在10 mL带塞离心试管中加入 5.0 mL葡萄样品溶液,并加入1.0 mL丙酮(分散剂),振荡摇匀后以5000 r/min离心5 min,然后将上层清液转移至另一离心试管中,加10.0 μL氯苯(萃取剂),分散混匀后再以5000 r/min离心5 min,萃取剂氯苯相沉积到试管底部,吸取1.0 μL萃取相直接进样分析.在优化的实验条件下,3种杀菌剂的富集倍数可达788~876倍;检出限在6.0~8.0 μg/kg(S/N=3∶ 1)范围内.以α-六六六为内标,测定3种杀菌剂的线性范围为10~150 μg/kg,线性相关系数在0.9990~0.9995范围内.本方法已成功应用于葡萄样品中百菌清、克菌丹和灭菌丹残留的测定,平均加标回收率在92.3%~106.1%范围内;相对标准偏差在4.5%~7.2%之间,结果令人满意.  相似文献   

15.
A simple, rapid, efficient, and environmentally friendly method for the determination of five triazine herbicides in water and soil samples was developed by using dispersive liquid-liquid microextraction (DLLME), coupled with high performance liquid chromatography-diode array detection (HPLC-DAD). The water samples were directly used for DLLME extraction. For soil samples, the target analytes were first extracted by water-methanol (99:1, v/v). In the DLLME extraction method, chloroform was used as an extraction solvent, and acetonitrile as a dispersive solvent. Under the optimum conditions, the enrichment factors of DLLME were in the range between 183-221. The linearity of the method was obtained in the range of 0.5-200 ng/mL for the water sample analysis, and 1-200 ng/g for the soil samples, respectively. The correlation coefficients ranged from 0.9968 to 0.9999. The limits of detection were 0.05-0.1 ng/mL for the water samples, and 0.1-0.2 ng/g for the soil samples. The proposed method has been successfully applied to the analysis of target triazine herbicides (simazin, atrazine, prometon, ametryn, and prometryn) in water and soil samples with satisfactory results.  相似文献   

16.
During the past 7 years and since the introduction of dispersive liquid–liquid microextraction (DLLME), the method has gained widespread acceptance as a simple, fast, and miniaturized sample preparation technique. Owing to its simplicity of operation, rapidity, low cost, high recovery, and low consumption of organic solvents and reagents, it has been applied for determination of a vast variety of organic and inorganic compounds in different matrices. This review summarizes the DLLME principles, historical developments, and various modes of the technique, recent trends, and selected applications. The main focus is on recent technological advances and important applications of DLLME. In this review, six important aspects in the development of DLLME are discussed: (1) the type of extraction solvent, (2) the type of disperser solvent, (3) combination of DLLME with other extraction methods, (4) automation of DLLME, (5) derivatization reactions in DLLME, and (6) the application of DLLME for metal analysis. Literature published from 2010 to April 2013 is covered.  相似文献   

17.
Recently, increasing interest on the use of dispersive liquid–liquid microextraction (DLLME) developed in 2006 by Rezaee has been found in the field of separation science. DLLME is miniaturized format of liquid–liquid extraction in which acceptor-to-donor phase ratio is greatly reduced compared with other methods. In the present review, the combination of DLLME with different analytical techniques such as atomic absorption spectrometry (AAS), inductively coupled plasma-optical emission spectrometry (ICP-OES), gas chromatography (GC), and high-performance liquid chromatography (HPLC) for preconcentration and determination of inorganic analytes in different types of samples will be discussed. Recent developments in DLLME, e.g., displacement-DLLME, the use of an auxiliary solvent for adjustment of density of extraction mixture, and the application of ionic liquid-based DLLME in determination of inorganic species even in the presence of high content of salts are presented in the present review. Finally, comparison of DLLME with the other liquid-phase microextraction approaches and limitations of this technique are provided.  相似文献   

18.
In this study, silica modified with a 30‐membered macrocyclic polyamine was synthesized and first used as an adsorbent material in SPE. The SPE was further combined with ionic liquid (IL) dispersive liquid–liquid microextraction (DLLME). Five polycyclic aromatic hydrocarbons were employed as model analytes to evaluate the extraction procedure and were determined by HPLC combined with UV/Vis detection. Acetone was used as the elution solvent in SPE as well as the dispersive solvent in DLLME. The enrichment of analytes was achieved using the 1,3‐dibutylimidazolium bis[(trifluoromethyl)sulfonyl]imide IL/acetone/water system. Experimental conditions for the overall macrocycle‐SPE–IL‐DLLME method, such as the amount of adsorbent, sample solution volume, sample solution pH, type of elution solvent as well as addition of salt, were studied and optimized. The developed method could be successfully applied to the analysis of four real water samples. The macrocyclic polyamine offered higher extraction efficiency for analytes compared with commercially available C18 cartridge, and the developed method provided higher enrichment factors (2768–5409) for model analytes compared with the single DLLME. Good linearity with the correlation coefficients ranging from 0.9983 to 0.9999 and LODs as low as 0.002 μg/L were obtained in the proposed method.  相似文献   

19.
A simple and miniaturized pretreatment procedure combining matrix solid‐phase dispersion (MSPD) with ultrasound‐assisted dispersive liquid–liquid microextraction (UA‐DLLME) technique was proposed in first time for simultaneous determination of three pyrethroids (fenpropathrin, cyhalothrin and fenvalerate) in soils. The solid samples were directly extracted using MSPD procedure, and the eluent of MSPD was used as the dispersive solvent of the followed DLLME procedure for further purification and enrichment of the analytes before GC‐ECD analysis. Good linear relationships were obtained for all the analytes in a range of 5.0–500.0 ng/g with LOQs (S/N=10) ranged from 1.51 to 3.77 ng/g. Average recoveries at three spiked levels were in a range of 83.6–98.5% with RSD≤7.3%. The present method combined the advantages of MSPD and DLLME, and was successfully applied for the determination of three pyrethroids in soil samples.  相似文献   

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