Triton X-114萃取法去除脑膜炎球菌荚膜多糖中的内毒素

目的采用Triton X-114萃取法去除A群脑膜炎球菌荚膜多糖中的内毒素。方法1% Triton X-114与多糖溶液在0℃混合均匀,分别加热至25、37和56℃,观察分层情况。离心后收集上层水相,对其中残余萃取剂Triton X-114进行去除方法的选择。比较多糖浓度对萃取的影响及二次萃取的效果,并对终产物进行全面检定。对W135群和Y群脑膜炎球菌多糖进行萃取效果比较。结果最终选择56℃10min作为升温条件,3000r/min离心10min后,上清中多糖的内毒率含量均减少85%以上,多糖回收率不低于80%。残余的Triton X-114选择透析法去除。多糖浓度越低,越易于萃取。二次萃取多糖回收率大于85%。内毒素含量可降低至0.706EU/μg多糖。经检测,终产物多糖的相对分子质量未发生改变,免疫原性与萃取前差异无显著意义,异常毒性、多糖及内毒素含量合格。蛋白含量稍有增加,核酸含量降低。W135群和Y群脑膜炎球菌多糖的萃取结果与A群多糖相似。结论Triton X-114萃取法可以用于去除脑膜炎球菌多糖中的内毒素。     

Cloud Point Extraction (CPE) of Parabens using Nonionic Surfactant Phase Separation

A cloud point extraction (CPE) method was developed using silicone-ethylene oxide surfactant, DC193C, to study the equilibrium phase separation of parabens in environmental water samples. The volume of the surfactant rich phase (V_s), aqueous phase (V_w), preconcentration factor (C_F), distribution coefficient (K_d), and percentage of recovery (%R) were evaluated to obtain the optimum condition for phase separation of parabens. Satisfactory results were obtained whereby the preconcentration factor for methylparaben, ethylparaben, propylparaben, and benzylparaben were close to 65, 60, 80, and 45, respectively, at 0.5% weight of surfactant. The presence of DC193C gave a low phase volume ratio but insignificant result was observed with the increased of surfactant concentration. The parabens were well separated on a reverse-phase Chromolith C₁₈ column (100 mm × 4.6 mm) with a gradient elution (acetonitrile: water; 30:70 v/v) and detected at 254 nm. The proposed method was successfully applied to environmental samples such as river water, treated wastewater, sea water, and tap water with satisfactory results. The method detection limit was 0.1–0.2 ppb and the recoveries were 71.2–97.7% with the relative standard deviations of 0.3–2.1%.     

Cloud Point Extraction of Copper,Zinc, Iron and Nickel in Biological and Environmental Samples by Flame Atomic Absorption Spectrometry

Abstract

Cloud point methodology was successfully employed for preconcentration of trace copper, zinc, iron, and nickel prior to their determination by flame atomic absorption spectrometry (FAAS). The metals react with 2-phenyl-1H-benzo[d] imidazole (PHBI) in a surfactant Triton X-114 medium. The effects of analytical parameters including pH, amounts of reagents etc. were investigated on the recoveries of analytes. No influences were observed from the matrix ions. The detection limits (3SD_b/m) of 1.8, 2.8, 1.4, and 2.1 ng mL^?1 for Cu²⁺, Fe³⁺, Zn²⁺, and Ni²⁺, respectively. The method was applied to metal determination in various real samples. The validation of the procedure was carried out by analysis of a certified reference biological material, BCR 185 R liver samples.     

Micelle-Mediated Extraction and Cloud Point Preconcentration of Chlorophylls from Spinach

A micelle-mediated extraction and cloud point preconcentration of chlorophylls method was developed. Non-ionic surfactant (Genapol X-080) was employed as an alternative and effective extraction solvent. The optimal extraction parameters based on the micelle extraction technique were determined. Under optimal conditions, i.e., 5% Genapol X-080 (v/v), pH 9.0, liquid/solid ratio of 10:1 (mL g^?1), ultrasonic-assisted extraction for 30 min, extraction amount reached the highest value. For the preconcentration of chlorophylls by cloud point extraction (CPE), the solution was incubated at 50° for 30 min, and 0.1 g mL^?1 sodium chloride was added to the solution to facilitate the phase separation. The microstructure of coacervate phase after CPE was explored with transmitting electron microscopy. The preconcentration factor for chlorophylls was about 12.5, the extraction recovery approached 99.2%, and the loading capacity was about 1 mg mL^?1. Thus coupling of ultrasonic-assisted micelle extraction and cloud point extraction could be employed as a new and effective technique for the rapid extraction and preconcentration of chlorophylls from plants such as spinach.     

Cloud Point Extraction and Pre-Concentration of Four Alkaloids in Nelumbo nucifera Leaves by Ultrahigh Pressure-Assisted Extraction

A rapid micellar extraction and pre-concentration method by ultrahigh pressure-assisted was developed for four alkaloids in Nelumbo nucifera leaves. Nonionic surfactant polyoxyethylene octylphenol ether (OP-10) solution was selected as solvent. Various experimental conditions were investigated to optimize the extraction and pre-concentration process. The optimal UPE condition was 5% OP-10 (w/w) solution, 400 MPa of pressure, 1 min of extraction time, and 1:20 (g/mL) of solid/liquid ratio. The pre-concentration of alkaloids was achieved by cloud-point extraction (CPE) and the optimum CPE condition was incubated in a thermostatic water bath at 55°C for 10 min, with 10% OP-10 and 15% sodium chloride added into the solution. The pre-concentration factor (CF) value was 11.6 ± 0.127, and the CPE recoveries for O-nornuciferine, N-nornuciferine, nuciferine, and roemerine were 91.0%, 92.3%, 92.7%, and 94.5%, respectively.     

Aqueous Surfactant Two‐Phase Systems for the Continuous Countercurrent Cloud Point Extraction

Aqueous nonionic surfactant solutions split into two phases if the temperature is increased beyond a certain temperature, the so‐called cloud point temperature. Presently many different types of nonionic surfactants are produced commercially, out of these numerous have been considered as potential solvent for the cloud point extraction. In this work the crucial thermophysical properties of nonionic surfactants are investigated to determine the potential of surfactant systems for extraction processes. Phase equilibria of the binary system Triton X‐114/water and the ternary system Triton X‐114/water/phenol were measured. Based on these data the cloud point extraction was implemented in a continuous stirred extraction column. It was found, that increasing temperature within the column reduces the loss of surfactant and leads to an increasing enrichment factor. This work demonstrates that surfactant/water systems represent a suitable alternative to conventional solvents and can effectively be processed in continuous extraction columns.     

Microemulsion Extraction of Monascus Pigments from Nonionic Surfactant using High Polarity of Diethyl Ether as Excess Oil Phase

Stripping of organic compound from nonionic surfactant micelle aqueous solution is indispensable for many industrial processes. In this paper, a relatively high polarity diethyl ether was screened for forming Winsor I microemulsion, which was used for stripping of organic compound from nonionic surfactant. Setting up extractive fermentation of Monascus pigments in Triton X-100 aqueous solution as a model, cloud point extraction of Monascus pigments from fermentation broth, and back-extraction of Monascus pigments from the coacervate phase of cloud point system by Winsor I microemulsion were conducted. Monascus pigments were successfully separated from nonionic surfactant into the excess diethyl ether phase.     

非离子表面活性剂TX114浊点萃取D2EHPA的规律

引言浊点萃取[1-2]是利用表面活性剂水溶液的增溶和分相行为实现溶质富集的分离技术。由于分相后表面活性剂的富集相(亦称凝聚相)与水相的体积比非常小(0.007～0.04)[3],所以,对于被增溶的物质能够提供非常高的富集倍数和萃取效率。目前浊点萃取技术主要广泛应用于痕量有害物质     

添加剂的浓度对非离子表面活性剂AEO9浊点的影响

各类添加剂都能对非离子表面活性剂的浊点产生影响.今研究了离子型表面活性剂、增溶物和电解质类添加剂在不同浓度下对非离子表面活性剂AEO9浊点的影响.其中离子型表面活性剂和增溶物类添加剂可在极低的浓度上改变AEO9的浊点,且随着添加剂加入浓度的增加,AEO9的浊点也逐渐增加,当添加剂浓度达到离子型表面活性剂或增溶物的临界胶束浓度时,AEO9的浊点将出现急剧上升.而电解质类添加剂对AEO9浊点的影响表现出具有临界浓度现象,只有当添加剂的浓度达到相应的临界浓度之后,具有盐析效应的电解质将使AEO9浊点线性下降,而具有盐溶效应的电解质则使AEO9浊点线性升高,且不同电解质相应的临界浓度随着其阴离子的感胶离子数的增大而线性增加,同时其对AEO9浊点的改变程度则随着阴离子的感胶离子数的增大而线性下降.     

The Binding of Anionic Dyes by Cross-Linked Cationic Starches

Adsorption of anionic dyes on the cross-linked with epichlorohydrin starches containing quaternary ammonium groups (CCS) was investigated and compared with that of modified starches containing only quaternary ammonium groups (CS). The adsorption of anionic dyes on CS and CCS closely follows the Langmuir model of adsorption. The computed Langmuir saturation capacity Q _o increases with increasing degree of substitution (DS) of CS or CCS and has the value from 0.81 mol/kg to 3.22 mol/kg for CCS and from 0.88 mol/kg to 1.87 mol/kg for CS. The effectiveness of the cationic groups in dye binding was about 1 mol/equiv for CSS with DS from 0.47 to 0.62 and all the cationic groups had attached one anionic groups of the dye. Increasing DS of CS decreases the effectiveness of dye binding due to the increase in solubility of CS, and the soluble part of CS binds the dye as a typical soluble polyelectrolyte. CCS are more suitable than CS for the anionic dye adsorption from a textile dyeing solution. DS of CCS should be about 0.5–0.6. They adsorb the anionic dyes in few minutes and acts in the wide range of pH of the solutions. The Langmuir saturation capacity Q _o and the effectiveness of the cationic groups in dye binding increase with an increase of the adsorption temperature. The positive values of the enthalpy and entropy suggest that the adsorption is endothermic and during the adsorption of the anionic dye on CCS the randomness of the system increases.     

Cloud Point Extraction of Parabens Using Non-Ionic Surfactant with Cylodextrin Functionalized Ionic Liquid as a Modifier

A cloud point extraction (CPE) process using non-ionic surfactant (DC193C) to extract selected paraben compounds from water samples was investigated using reversed phase high performance liquid chromatography (RP-HPLC). The CPE process with the presence of β-cyclodextrin (βCD) functionalized ionic liquid as a modifier (CPE-DC193C-βCD-IL) is a new extraction technique that has been applied on the optimization of parameters, i.e., pH, βCD-IL concentration and phase volume ratio. This CPE-DC193C-βCD-IL method is facilitated at 30 °C, showing great losses of water content in the surfactant-rich phase, resulting in a high pre-concentration factor and high distribution coefficient. The developed method CPE-DC193C-βCD-IL did show enhanced properties compared to the CPE method without the modifier (CPE-DC193C). The developed method of CPE-DC193C-βCD-IL gives an excellent performance on the detection of parabens from water samples with the limit of detection falling in the range of 0.013–0.038 μg mL⁻¹. Finally, the inclusion complex formation, hydrogen bonding, and π–π interaction between the βCD-IL, benzyl paraben (ArP), and DC 193C were proven using ¹H NMR and 2D NOESY spectroscopy.     

Cloud Point Extraction of Glycyrrhizic Acid from Licorice Root

Abstract

An attempt has been made to extract glycyrrhizic acid (GA) from licorice root by surfactant mediated cloud point extraction (CPE) using non‐ionic surfactant (Triton X‐100). Almost all of the GA molecules were concentrated in the surfactant‐rich phase (also called coacervate phase) after phase separation. The pH is the most critical factor regulating the distribution of GA in the micelle which related to the ionization form. The other effects of the concentration of GA and the surfactant, the temperature, and the salt concentration on the extraction efficiency of GA in the coacervate phase and aqueous phase have been studied. The mechanism of CPE of GA was explored with transmitting electron microscopy. It was deduced that aggregate GA molecules were adsorbed on micelles' outer poler mantle and inner cross‐linked micelles at high GA concentrations in coacervate phase.     

十二烷基硫酸钠对非离子表面活性剂CM101浊点的影响

研究了阴离子表面活性剂十二烷基硫酸钠(SDS)对非离子表面活性剂CM101浊点的影响。结果表明:当SDS加入量为2%时,CM101的浊点提高到59.6℃,达到农药制剂热稳定性的要求。同时,该混合体系满足非理想二元表面活性剂复配增效的条件,表面张力和临界胶束浓度都有明显降低。     

Photophysical Separation of Conformational Isomers by Microwave Radiation Applied to Molecular Beams

Abstract

A method is proposed by which an experimental quantity of a pure con-former can be stabilized and isolated for the separate study of its reactions. Similarly, isotopic compounds can be enriched on a laboratory scale. Due to the low-temperature feature of the proposed method, microwave spectroscopy can be applied to volatilizable large molecules.     

浊点萃取技术在环境样品分析中的应用

浊点萃取技术(CPE)是近年来提出的一种新型的液-液、液-固萃取分离提取技术,是将表面活性剂应用于分析化学领域的一种重要而实用的技术,具有萃取效率高、富集因子大、操作简便、安全、无需大量有机溶剂等优点。适用于环境样品中金属离子及痕量有机污染物的分析。本文主要介绍了CPE技术在环境样品分析中的应用,且探讨了该技术的发展前景。     

Cloud Point Extraction of Acetic Acid from Aqueous Solution

Abstract

A new acetic acid separation method was developed through a successful combination of cloud point extraction and complex extraction technology (CPE-SE), where an acetic acid complex compound formed and was solubilized in a surfactant micelle solution, instead of an organic solvent, and then concentrated into one phase by a phase separation process of the CPE technology. Since no organic solvent diluents were used, the new process was environmentally friendly and with a lower cost; meanwhile, the high selectivity of the complex extraction based on chemical complexation and high efficiency of CPE were also inherited as advantages over conventional solvent extraction process. In consideration of the compatibility and the related CPE characteristics, tributyl phosphate and PEG/PPG-18/18 Dimethicone were selected as complexing agent and surfactant of the CPE-SE system, respectively, and the extraction system was optimized by studying the effect of the main process parameters, including surfactant and complexing agent concentration, temperatures for the stirring and incubation steps, on the recovery and the distribution coefficient. A relative high recovery of 71.4% and a distribution coefficient of 1.4 were achieved simultaneously with the optimized process in the treatment of 0.1 M acetic acid solution. Based on its competitive extractability, high efficiency, low-cost, and environment friendlyness, the CPE-SE process was expected to be a potential separation method for a dilute acetic acid solution.     

浊点萃取-FAAS法测定化妆品中六价铬

提出了浊点萃取-火焰原子吸收光谱法测定化妆品中痕量六价铬的方法。考察了溶液pH、APDC用量、Triton X-114用量、平衡温度及时间等条件对浊点萃取率的影响,在优化条件下,对化妆品进行测定。该方法测定铬的检出限为0.026 mg/L,相对标准偏差为1.52%。结果表明：市售多数化妆品中的铬含量超过国家标准,须引起质量监督部门的注意。     

相分离辅助方法对有机硅表面活性剂浊点萃取PAHs的影响

相分离性能和萃取率是评价浊点萃取(CPE)性能的两个重要因素.对于采用非离子表面活性剂的CPE,当溶液加热至浊点以上,仅依靠热运动来促使其发生相分离是十分缓慢的,因此通常需要一定的辅助方法来加速其相分离的进程.今利用两种聚醚型有机硅表面活性剂DC-193和DC-190,对蒽、菲、芘和苊四种多环芳烃(PAHs)进行浊点萃取研究,分别使用加热、加盐、离心和搅拌等辅助方法改变相分离过程的速度.通过测定表面活性剂富集相的体积百分率Vs/(Vs Vw)随时间的变化和最终的萃取率,研究上述四种不同辅助方法对相分离行为和萃取性能的影响.结果表明,相分离速度:加盐＜加热＜离心＜搅拌;Vs/(Vs Vw):搅拌＜离心＜加盐＜加热;萃取率:加热＜加盐≈离心＜搅拌.可见,离心与搅拌辅助CPE具有较大的优势,可同时提供更高的相分离性能和萃取率.与离心相比,搅拌的引入所需设备更简单,而且对于容器的体积没有限制,易于实现连续操作,更有望应用于实际的大规模水处理之中.     

浊点萃取-火焰原子吸收法测定水中的痕量钴

研究了以DDTC作为配位剂,浊点萃取预富集-火焰原子吸收法应用于水样中痕量的钴测定的实验方法;对实验条件进行了优化,用该方法对水样中的钴含量进行了测定,并对此方法的可靠性和精确性进行了验证。     

浊点萃取火焰原子吸收法测定水样中痕量铅的研究

以浊点革取-火焰原子吸收光谱法测定痕量铅,探讨了实验条件对浊点草取及测定灵敏度的影响。在最佳条件下,铅富集倍数达到20倍。该方法可用于自来水、井水及河水中痕量铅的测定。