浊点萃取-火焰原子吸收光谱法测定某些中药中的铜含量

浊点萃取(Cloud Point Extraction,CPE)是近年来出现的一种新兴的环保型的液-液萃取技术,它不使用挥发性有机溶剂,对环境的影响较小[1].它以中性表面活性剂胶束水溶液的溶解性和浊点现象为基础,通过改变试验参数如溶液pH值、温度等引发相分离,将疏水性物质与亲水性物质分离.它具有经济、安全、高效、简便等优点,已广泛应用于生命科学和环境科学研究中[2-4],特别是在痕量金属元素的分离富集方面取得了很大的成功[5-7].     

浊点萃取在生物大分子分离及分析中的应用

浊点萃取是一种新兴的环保型液2液萃取方法。本文介绍了表面活性剂胶束溶液的形成过程和浊点现象, 总结了浊点萃取法的操作方法, 并且详细讨论了它在生物大分子分离纯化及生物分析中的应用。最后探讨了该技术的发展前景。     

浊点萃取在金属离子形态分析中的应用

浊点萃取是一种新兴的环保型的液-液萃取方法,它不使用有机溶剂,易于操作,是一种绿色的分析技术.本文介绍了浊点萃取的原理,重点回顾了近年来该技术在金属离子形态分析中的应用,并探讨了该技术的应用前景.     

浊点萃取技术在金属离子分离和富集以及形态分析中应用的进展

介绍了新兴的环保型液液萃取方法——浊点萃取的原理及操作方法，讨论了影响浊点萃取效率的因素，重点回顾了近年来该技术在金属离子分离和富集以及形态分析中应用的进展，探讨了该技术的发展前景。     

浊点萃取技术的应用

浊点萃取是近年发展起来的一种新兴的萃取技术。重点阐述了浊点萃取在环境样品、生物样品和食品工业分析中的应用,总结了浊点萃取技术的优点,指出了存在的问题,探讨了该技术的发展前景。     

8-羟基喹啉-浊点萃取-流动分析光度法测定果蔬中铬价态

1 引言 浊点萃取法是一种新兴的液-液萃取技术,具有很高的富集倍数和提取率.流动分析光度法通常一次进样只需0.5～1.0 mL,可节省试样,减少二次污染.浊点萃取法与流动分析光度法结合可优势互补,更快速、简便.Cr(Ⅲ)是人体维持生命的必需元素,而Cr(Ⅵ)在生物体系内有很强的流动性和氧化性.因此,分析不同价态铬十分重要.铬价态的分析方法主要有共沉淀、萃取、离子交换、色谱等方法.基于Triton X-100的浊点现象,选择8-羟基喹啉为螯合萃取剂,在优化的实验条件下,使Cr(Ⅲ)-8-羟基喹啉 "原位"进入其富胶束相,Cr(Ⅵ)留在水相而彼此得以分离,提出了浊点萃取-流动分析光度法测定不同价态铬的新方法.     

金属检测中新型前处理技术研究进展及应用

精准检测环境和食品中金属含量对环境保护和人体健康至关重要.样品的准备环节是造成样品损失和二次污染的关键步骤, 因此合适的前处理方法可以提高金属分析的选择性和灵敏度.从液相萃取和非液相萃取新技术两方面综述了浊点萃取、离子液体、超分子溶剂-分散液液微萃取、顶空固相微萃取技术、超临界流体萃取特点及在复杂样品前处理中的应用和研究进展, 并对其未来发展方向进行了展望.     

浊点萃取在痕量金属元素分析中的应用

浊点萃取(CPE)法是一种新兴的环保型液_液萃取技术，可以作为痕量金属元素的预富集方法。此文总结了CPE法在痕量金属元素分析中应用原理、方法及试验条件优化，概括了CPE作为预富集法在不同分析检测仪器中的应用，探讨了该技术方法的应用前景。     

高效液相色谱结合浊点微萃取测定烟叶中麦角甾醇北大核心CSCD

本研究建立了一种简单、快速及灵敏测定烟叶中麦角甾醇的高效液相色谱新方法。方法基于脂肪酸基酸碱诱导浊点萃取(AB-CPE)技术,以己酸为萃取剂,通过加入碱诱导酸碱反应形成混浊均相,再加入酸进行相分离从而对麦角甾醇进行浊点萃取。考察并优化了影响分散液液微萃取的实验条件,包括萃取剂和分散剂种类及用量、pH和离子强度。在最优条件下,该方法在1~1000 mg/kg之间具有良好的线性关系,相关系数R^(2)≥0.997。方法的检出限(S/N=3)和定量限(S/N=10)分别是0.08 mg/kg和0.26 mg/kg,实际烟叶样品的加标回收率在92.5%~102.3%范围内,相对标准偏差(RSD)小于2.2%。该方法成功应用于烟草中麦角甾醇的定量检测。     

浊点萃取-分光光度法测定自来水及酒类样品中的痕量铁

利用非离子表面活性剂TritonX-100在温度高于其浊点时形成相分离行为,建立了浊点萃取-分光光度法测定痕量铁的新方法,探讨优化了以KSCN为显色剂,TritonX-100浊点萃取富集痕量铁的实验条件.研究发现:加入正辛醇可使TritonX-100的浊点降低约30℃,有利于萃取实验的进行;同时,加入的正辛醇与TritonX-100对痕量铁起到了协同萃取作用.在优化了的实验条件下,进行了痕量铁的分析,检出限为0.02mg·L-1,加标回收率为97.4%～101.6%,应用于自来水及酒类样品中痕量铁的测定,结果满意.     

浊点萃取-紫外可见分光光度法测定痕量金

建立了以四甲基联苯胺(TMB)为络合剂,非离子表面活性剂Triton-114为萃取剂的浊点萃取-紫外可见分光光度法测定痕量金的方法。考察了溶液的pH、络合剂和表面活性剂浓度、平衡温度和时间等条件对浊点萃取的影响。在最优条件下,该方法对金的富集倍数为12倍,线性范围为0～0.5μg/mL,检出限(3σ)为8.6ng/mL,相对标准偏差RSD为2.3%～3.6%(n=6),回收率在97%～102%之间。方法已用于工业废水中痕量金的测定。     

Design of rapidly synergistic cloud point extraction of ultra-trace lead combined with flame atomic absorption spectrometry determination

In this work, traditional cloud point extraction (CPE) pattern was changed and improved by the proposed rapidly synergistic CPE. Using octanol as cloud point revulsant and synergic reagent, non-ionic surfactant Triton X-114 (TX-114) accomplished room temperature extraction rapidly without heating in water bath. The improved extraction was named as rapidly synergistic cloud point extraction (RS-CPE). Compared with traditional CPE, RS-CPE was accomplished in 1 min with considerably high extraction efficiency. The improved CPE pattern was coupled with flame atomic absorption spectrometry (FAAS) for the extraction and detection of trace lead in real and certified water samples with satisfactory analytical results. The proposed method greatly improved the sensitivity of FAAS for the determination of lead. Under the optimal conditions, the limit of detection (LOD) for lead was 4.3 μg/L, with enhancement factor (EF) of 39. Factors influencing RS-CPE efficiency, such as concentrations of surfactant TX-114 and octanol, concentration of chelating agent, pH, conditions of phase separation, environmental temperature, salt effect and instrumental conditions, were studied systematically.     

Highly selective cloud point extraction and preconcentration of trace amounts of silver in water samples using synthesized Schiff’s base followed by flame atomic absorption spectrometric determination

A simple and useful method employing cloud point extraction is proposed for the preconcentration and separation of silver in water samples. The silver cation reacts with bis(2-mercaptoanil) acetylacetone (BMAA) at pH 6. The resulting compound is subsequently entrapped in the Triton X-114 micelles. After optimization of the complexation and extraction conditions, a preconcentration factor of 50 was obtained (volume of initial sample was 10 mL). As an analytical example, trace amounts of Ag were determined, after preconcentration, in a complex aqueous matrix such as seawater using flame atomic absorption spectrometry. The calibration curve was linear in the range 2–200 ng/mL and the limit of detection was 0.43 ng/mL. The relative standard deviation was lower than 2.4%. The text was submitted by the authors in English.     

固相萃取-石墨炉原子吸收法光谱分析铝合金中痕量铍的研究

建立了固相萃取-石墨炉原子吸收光谱法测定铝合金中铍的方法。利用偶氮砷酸类试剂7-(2′-胂酸基-5′-羧酸)苯偶氮-8-羟基喹啉-5-磺酸(H2L)与Be2+形成螯合物,该螯合物可用C18固相萃取柱富集,而Al3+则不被保留。采用石墨炉原子吸收光谱法(GF-AAS)测定C18柱洗脱液中的Be2+的螯合物,从而实现铝合金中铍的分离检测。最佳实验条件为:采用pH=3.0的5%H2L水溶液螯合Be2+,水相上柱,用2mL体积比为50%的甲醇/水溶液作为洗脱液。结果表明:经过C18柱固相萃取可以去除Al3+的干扰,Be2+的测定范围为0.05～16μg/L,检出限为0.025μg/L,加标回收率为92%～108%。应用该法于铝合金标样中铍的测定,结果与认定值相符。     

浊点萃取-火焰原子吸收光谱法测定样品中的痕量钴

研究了基于表面活性剂Triton X-114和络合剂吡咯烷二硫代氨基甲酸铵（APDC）浊点萃取钴的样品前处理方法.优化了浊点萃取条件参数,包括pH值、Triton X-114用量、APDC浓度、平衡温度及时间等,建立了浊点萃取-火焰原子吸收光谱法测定痕量钴的方法.该法的检测限（3σ）为2.6μg/L,相对标准偏差RSD为6.2%（n=7,c=200μg/L）.该法成功地应用于海带、维生素B12注射液等样品中钴的测定.     

Cloud point extraction preconcentration of manganese(II) from natural water samples using 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone and triton X-100 and determination by flame atomic absorption spectrometry.

The possibility was investigated by using 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) as the chelating reagent for separation and preconcentration of manganese(II) by cloud point extraction (CPE) and subsequent determination by flame atomic absorption spectrometry (FAAS). The effects of experimental conditions such as pH, concentration of chelating agent and surfactant, equilibration temperature and time on cloud point extraction were studied. Under the optimum conditions, preconcentration of 10 ml of sample solution permitted the detection of 1.45 ng mL(-1) of manganese with an enrichment factor of 20. The proposed method was applied to the determination of trace manganese in water samples with satisfactory results.     

浊点萃取-分光光度法测定痕量NO2-

建立了浊点萃取-分光光度法测定痕量NO2-根的方法.以对氨基苯磺酸和α-萘胺为络合剂,非离子型表面活性剂TritonX-100为萃取剂,富集、分离水样中痕量NO2-,采用可见吸收光谱法进行检测.研究了溶液的酸度、试剂用量、平衡时间、平衡温度、干扰离子对浊点萃取效果的影响,并得到最佳实验条件:5％的TritonX-100用量2.0mL、平衡温度85℃、平衡时间10min、对氨基苯磺酸和α-萘胺均为0.3mL、0.1mol/LH2SO4溶液0.5mL.在最佳实验条件下,对氨基苯磺酸、α-萘胺和NO2-生成的络合物被萃取到TritonX-100表面活性剂相并与水相分开.该方法适用于环境水样中痕量NO2-的测定.     

Cloud point extraction–thermospray flame quartz furnace atomic absorption spectrometry for determination of ultratrace cadmium in water and urine

A simple, low cost and highly sensitive method based on cloud point extraction (CPE) for separation/preconcentration and thermospray flame quartz furnace atomic absorption spectrometry was proposed for the determination of ultratrace cadmium in water and urine samples. The analytical procedure involved the formation of analyte-entrapped surfactant micelles by mixing the analyte solution with an ammonium pyrrolidinedithiocarbamate (APDC) solution and a Triton X-114 solution. When the temperature of the system was higher than the cloud point of Triton X-114, the complex of cadmium-PDC entered the surfactant-rich phase and thus separation of the analyte from the matrix was achieved. Under optimal chemical and instrumental conditions, the limit of detection was 0.04 μg/L for cadmium with a sample volume of 10 mL. The analytical results of cadmium in water and urine samples agreed well with those by ICP-MS.     

Cloud point extraction and preconcentration of gold in geological matrices prior to flame atomic absorption determination

Brilliant green was used as a complexing agent in cloud point extraction (CPE) and applied for selective preconcentration of trace amounts of gold in geological matrices. The analyte in the initial aqueous solution was acidified with hydrochloric acid (0.1 M) and octylphenoxypolyethoxyethanol (Triton X-114) was added as a surfactant. After phase separation, based on the cloud point separation of the mixture, the surfactant rich phase was diluted with methanol and the analyte determined in the surfactant rich phase by flame atomic absorption spectrometry (FAAS). After optimization of the complexation and extraction conditions, a preconcentration factor of 31 was obtained for only 10 mL of sample. The analytical curve was linear in the range of 3–1000 ng mL⁻¹ and the limit of detection was 1.5 ng mL⁻¹. The proposed method was applied to the determination of gold in geological samples.     

Development of a simple and valid method for the trace determination of phthalate esters in human plasma using dispersive liquid–liquid microextraction coupled with gas chromatography–mass spectrometry

A new method was developed for the trace determination of phthalic acid esters in plasma using dispersive liquid–liquid microextraction and gas chromatography with mass spectrometry analysis. Plasma proteins were efficiently precipitated by trichloroacetic acid and then a mixture of chlorobenzene (as extraction solvent) and acetonitrile (as dispersive solvent) rapidly injected to clear supernatant using a syringe. After centrifuging, chlorobenzene sedimented at the bottom of the test tube. 1 μL of this sedimented phase was injected into the gas chromatograph for phthalic acid esters analysis. Different factors affecting the extraction performance, such as the type of extraction and dispersive solvent, their volume, extraction time, and the effects of salt addition were investigated and optimized. Under the optimum conditions, the enrichment factors and extraction recoveries were satisfactory and ranged between 820–1020 and 91–97%, respectively. The linear range was wide (50–1000 ng/mL) and limit of detection was very low (1.5–2.5 ng/mL for all analytes). The relative standard deviations for analysis of 1 μg/mL of the analytes were between 3.2–6.1%. Salt addition showed no significant effect on extraction recovery. Finally, the proposed method was successfully utilized for the extraction and determination of the phthalic acid esters in human plasma samples and satisfactory results were obtained.