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1.
参照文献方法合成了BSA保护的水溶性发光金纳米粒子, 并考察了此探针在非离子表面活性剂曲通X-100中的发光行为.根据观察到的发光增强效应, 建立了一种简单的测定曲通X-100的方法.考察了发光金纳米粒子的浓度、体系酸度、反应时间及共存物质对测定的影响.在最佳条件下, 发光强度与曲通X-100的浓度分别在0~150 μmol/L和150~600 μmol/L范围内分段成正比关系.两条工作曲线的交点所对应的浓度与曲通X-100的临界胶束浓度十分吻合, 为胶束形成过程提供了直接的指示.作为一种生物相容性探针, 发光金纳米粒子被用于生物学样品中曲通X-100的分析测定, 结果令人满意.  相似文献   

2.
用荧光共轭聚合物测定曲通X-100及其临界胶束浓度   总被引:1,自引:0,他引:1  
郝丹  孙礼林  晋英琼  朱昌青 《化学学报》2010,68(21):2215-2221
基于钯催化的偶联反应合成了疏水性荧光共轭聚合物, 聚[2,5-二壬氧基-1,4-苯撑-乙炔撑-9,10-蒽撑][poly (2,5-bisnonyloxy-1,4-phenylene-ethynylene-9,10-anthrylene) (PPEA)], 并研究了此聚合物在不同表面活性剂溶液中的荧光行为. PPEA在水溶液中荧光明显猝灭, 加入非离子表面活性剂曲通X-100时, 荧光逐渐增强, 而其它表面活性剂CTAB, SDS, Tween对PPEA的荧光强度无明显影响. 这可能是由于曲通X-100与PPEA有相似的脂肪碳链, 二者之间的疏水作用减小了聚合物不规则构象所造成的. 实验考察了有机溶剂THF用量、PPEA浓度、体系酸度、反应时间、共存物质对测定的影响. 最佳条件下, 聚合物荧光强度与曲通X-100的浓度分别在0~200和200~700 μmol/L范围内分段成线性关系, 且两段工作曲线的交点所对应的曲通X-100浓度与其临界胶束浓度(CMC)一致. 据此, 我们建立了一种基于荧光共轭聚合物的荧光方法. 该法允许在其它表面活性剂存在时选择性测定曲通X-100浓度, 也可方便地指示其CMC值.  相似文献   

3.
吐温80-硫酸铵-水固液体系萃取分离Rh(Ⅲ)和Ir(Ⅲ)   总被引:11,自引:1,他引:11  
铑;铱;液固萃取分离;氯化亚锡;吐温80-硫酸铵-水固液体系萃取分离Rh(Ⅲ)和Ir(Ⅲ)  相似文献   

4.
研究了硫酸铵-1-(2-吡啶偶氮)-2-萘酚-吐温80体系萃取Cu(Ⅱ)的行为及最佳分相条件。结果表明,在pH 6.8~8.5的NaOH-KH2PO4缓冲溶液中,在硫酸铵存在下,Cu(Ⅱ)-1-(2-吡啶偶氮)-2-萘酚的配合物可被吐温80固相完全富集而与Fe3+、Al3+、Co2+、Ni2+、Zn2+等定量分离。配合物最大吸收波长为560 nm,表观摩尔吸光系数7.35×104L.mol-1.cm-1,铜含量在0~14μg/10 mL范围内服从比耳定律。方法已用于粮食、茶叶等生物样品中痕量铜的测定,测定结果的RSD(n=7)小于4.1%,回收率在98.6%~103.9%之间。  相似文献   

5.
TritonX-100-5-Br-PADAP光度法测定发样中铁   总被引:2,自引:0,他引:2  
在表面活性剂Triton X-100存在下,以5-Br-PADAP作显色剂,光度法测定发样中铁,结果在所选浓度范围内线性关系良好,稳定时间长,回收率平均为98.14%。  相似文献   

6.
A modified taylor dispersion technique is used to measure liquid-phase mutual diffusion coefficients D. Rather than inject a narrow band of solution of solute concentration C+C into a carrier stream of composition C, the carrier stream is switched from a solution of composition C-(C/2) to a solution of composition C+(C/2), forming an initially-sharp moving boundary at the tube inlet. D is calculated from the refractive index profile across the broadened boundary at the tube outlet. Since the mean of concentration of the diffusing solute (C) is constant throughout the run, the calculated value of D accurately represents the differential value at C, even if relatively large concentration differences are used or if D is sensitive to composition. The advantages of the technique are illustrated by measuring the diffusion of aqueous Triton X-100, a nonionic surfactant. D is found to drop sharply as the concentration is raised through the critical micelle concentration near 0.15 g-L–1.  相似文献   

7.
抗生素头孢唑酮的加入使得非离子表面活性剂Triton X-100的表面活性降低. 1H-NMR的结果表明,头孢唑酮增溶于胶束极性基团附近.头孢唑酮与Triton X-100胶束的结合常数随Triton X-100含量的增加而下降,但头孢唑酮在Triton X-100胶束相和水连续相之间的分配系数不随Triton X-100含量变化而变化.  相似文献   

8.
The mechanisms governing the subsolubilizing and solubilizing interaction of sodium dodecyl sulphate (SDS)/Triton X-100 mixtures and phosphatidylcholine liposomes were investigated. Permeability alterations were detected as a change in 5(6)-carboxy-fluorescein (CF) released from the interior of vesicles and bilayer solubilization as a decrease in the static light-scattered by liposome suspensions. Three parameters were described as the effective surfactant/lipid molar ratios (Re) at which the surfactant system a) resulted in 50% of CF release (Re 50%CF); b) saturated the liposomes (Re SAT;c) led to a complete solubilization of these structures (Re SOL). From these parameters the corresponding surfactant partition coefficientsK 50%CF,K SAT andK SOL were determined. The free surfactant concentrationsS W were lower than the mixed surfactant CMCs at subsolubilizing level, whereas they remained similar to these values during saturation and solubilization of bilayers in all cases. Although theRe increased as the mole fraction of the SDS rose (X SDS), theK parameters showed a maximum atX SDS values of about 0.6, 0.4 and 0.2 forK 50%CF,K SAT andK SOL respectively. Thus, the higher the surfactant contribution in surfactant/lipid system, the lower theX SDS at which a maximum bilayer/water partitioning of mixed surfactant systems added took place and, consequently, the lower the influence of the SDS in this maximum bilayer/water partitioning.Abbreviations PC Phosphatidylcholine - PIPES piperazine-1,4 bis (2-ethanesulphonic acid) - SDS sodium dodecyl sulphate - X SDS mole fraction of sodium dodecyl sulphate in the mixed system - CF 5(6)-carboxyfluorescein - Re effective surfactant/lipid molar ratio - Re 50%CF effective surfactant/lipid molar ratio for 50% CF release - Re SAT effective surfactant/lipid molar ratio for bilayer saturation - Re SOL effective surfactant/lipid molar ratio for bilayer solubilization - S W surfactant concentration in the aqueous medium - S W, 50%CF surfactant concentration in the aqueous medium for 50% CF release - S W, SAT surfactant concentration in the aqueous medium for bilayer saturation - S W, SOL surfactant concentration in the aqueous medium for bilayer solubilization - S B surfactant concentration in the bilayers - K bilayer/aqueous phase surfactant partition coefficient - K 50%CF bilayer/aqueous phase surfactant partition coefficient for 50% CF release - K SAT bilayer/aqueous phase surfactant partition coefficient for bilayer saturation - K SOL bilayer/aqueous phase surfactant partition coefficient for bilayer solubilization - PL phospholipid TLC-FID, thin-layer chromatography/flame ionization detection system - PI polydispersity index - CMC critical micellar concentration - r 2 regression coefficient  相似文献   

9.
The location and aggregation of 5,10,15-tris(4-hydroxyphenyl)-20-(hexadecyloxyphenyl)porphyrin (P) in nonionic polyoxyethylene (9.5) octylphenol (Triton X-100) micelle solutions were studied by means of UV–Vis and fluorescence spectra. P forms premicelle surfactant–porphyrin aggregates when the surfactant concentration is below and approaching the CMC. In Triton X-100 micelle solutions, different types of H-aggregates of P were formed when the concentration of P is higher than 3.9×10-6?mol?dm-3. As the bulk pH is changed, a transfer process for the porphyrin moiety in Triton X-100 micelle occurs. In neutral Triton X-100 micelle solutions, P may be located at the inner layer of the micelle; in basic conditions, the porphyrin moiety may transfer to the outer surface of the micelle. The kinetic study of porphyrin complexed with Cu(II) in Triton X-100 micelle solutions shows that the metalation rate could be controlled by changing the pH.  相似文献   

10.
The presence of microdomains, called lipid rafts, in biological membranes is usually explained by lateral segregation between specific lipids and proteins. These rafts present similarities with the membrane domains isolated by their non-ionic detergent-resistance at 4 degrees C. They are enriched in sphingomyelin and cholesterol as compared with the outer leaflet of eukaryotic cell membranes. To understand the role played by the lipids enriched in rafts in their resistance to solubilization by detergents, the interactions between these lipids and the non-ionic detergent Triton X-100 were studied by using different lipid monolayers at the air-water interface. The influence of Triton X-100 on the Langmuir isotherms (i.e. surface pressure/area isotherms) of monolayers containing sphingomyelin and cholesterol at different mole ratios was analyzed and the results were compared with the influence of Triton X-100 on monolayers containing a phosphatidylcholine bearing a saturated and an unsaturated fatty acid (i.e. palmitoyloleylphosphatidylcholine) and cholesterol. This phosphatidylcholine was chosen since the phosphatidylcholines present in rafts isolated from bovine kidney could contain about 50% of saturated fatty acids. Triton X-100 induces an increase in the condensing effect observed as compared with ideal mixture of phospholipid/cholesterol. Triton X-100-induced changes in the morphology of the monolayers were visualized by Brewster angle microscopy, which confirmed the differences of behavior observed by analyzing the isotherms.  相似文献   

11.
对辛基苯酚惭烯型非离子表面活性剂TritonX-100和聚氧乙烯失水山梨醇脂肪?酯型非离子表面活性剂Tween-60进行毛细管超临界流体色谱法(CSFC)分析条件的研究,用CSFC连接通用型FID检测器研究了二种表面活性剂的组成和分子量,实验结果表明,TritonX-100中含量最多的低聚物的EO数(聚合的环氧乙烷数目)为9-10,分子量约600,Tween-60的分子量约为1500,与理论计算值  相似文献   

12.
The capacity of the glycoprotein (GP) excreted by Pseudoalteromonas antarctica NF3 to protect phosphatidylcholine (PC) liposomes against the action of Triton X-100 was studied in detail. Increasing amounts of GP assembled with liposomes resulted in a linear increase in the effective surfactant-to-PC molar ratios needed to produce the same alterations in liposomes and in a linear fall in the surfactant partitioning between the bilayer and the aqueous phase. Thus, the higher the proportion of GP assembled with liposomes the lower the surfactant ability to alter the permeability of vesicles and the lower its affinity with these bilayer structures. In addition, increasing GP proportions resulted in a progressive increase in the free surfactant concentration (S W) for the same surfactant–liposome interaction step. The fact that S W was always lower than the surfactant critical micelle concentration indicates that the interaction was mainly ruled by the action of surfactant monomers, regardless of the amount of GP assembled. Received: 4 May 1999 Accepted in revised form: 6 July 1999  相似文献   

13.
Triton X-100存在下镉试剂分光光度法测定痕量铊(III)   总被引:4,自引:0,他引:4  
本文首次提出了在Triton X-100存在下, 以镉试剂作显色剂于水相直接分光光度法测定了痕量铊, 结果表明: 该体系具有很高的灵敏度, 是目前分光光度法测定铊的最灵敏方法之一.  相似文献   

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