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1.
The hydrolysis of cephanone in Triton X-100 micelle and Triton X-100/n-C5H11OH/H2O(O/W) microemulsion were studied by means of UV-Vis absorption spectroscopy. The results show that compared with water, Triton X-100 micelle and Triton X-100/n-C5H11OH/H2O (O/W) microemulsion can inhibit the hydrolysis of cephanone. The inhibition effects of Triton X-100 micelle and Triton X-100/n-C5H11OH/H2O (O/W) microemulsion on the hydrolysis of cephanone are related to the location of cephanone in the interphases of Triton X-100 miceUes and Triton X-100/n-C5H11OH/H2O(O/W) microemulsion droplets.  相似文献   

2.
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   

3.
《印度化学会志》2023,100(9):101063
The interactions between the polyphenol quercetin, Q, with three surfactant aggregates with different electric charges named micelles, were studied in aqueous solutions with pH values 4.7 and 7.0, to determine the following parameters: critical micellar concentration (CMC), micelle size and binding constant of the complex (Q-Micelle) proposing interaction sites for the formation of the complex. The surfactants used were: hexadecyltrimethyl ammonium bromide (cationic surfactant), CTAB, sodium dodecyl sulfate (anionic surfactant), SDS, and triton X-100 (non-ionic surfactant), TX100, used as Q fluorescence promoters to determine the CMC. The CMC values of the above surfactants at pH 4.7 were: 0.80 ± 0.10, 1.39 ± 0.07 and 0.59 ± 0.05 mM respectively, being lower than those reported in the water. With dynamic light scattering measurements, the hydrodynamic diameters of each micelle were calculated resulting in values of: 2.4 ± 0.5, 5.0 ± 1.1 and 8.4 ± 4.3 nm at pH 4.7 and: 2.1 ± 0.4, 4.9 ± 1.1 and 11.5 ± 4.1 nm at pH 7.0 respectively. In addition, the binding constants of the complex (Q-Micelle) with 1:1 stoichiometry were calculated from emission fluorescence data giving Log K values: 2.94 ± 0.02, 2.54 ± 0.02, and 3.63 ± 0.05 M-1 respectively. Finally, from the experimental data by UV–Vis spectrophotometry, the change in the behavior of the Q spectrum upon the addition of each of the surfactants to the system was analyzed, showing a decrease in absorbance when SDS and TX100 were added in an acidic medium, as a consequence of the photo-instability of the drug, suggesting that Q interacts with the outside of these micelles and is not fully incorporated inside them.  相似文献   

4.
以1-(2-吡啶偶氮)-2-萘酚为络合剂,在pH 7.0,用Triton X-100非离子表面活性剂浊点萃取水样中痕量镍.表面活性剂相用硝酸-甲醇(1 9)混合液0.5 mL分散,所得溶液直接引入仪器进行火焰原子吸收测定,方法的检出限(3σ)为3.77×10-3mg·L-1,应用所提出方法测定了河水样品,测定结果的相对标准偏差(n=6)为2.98%.  相似文献   

5.
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   

6.
The effects of Triton X-100 molecule and micelle on the microstructure and properties of HSA are studied by the some methods of UV spectrum, fluorescence spectrum, fluorescence polarization, circular dichroism, conductivity, and zeta potential. With the increase of Triton X-100 concentration, the UV absorbance, fluorescence intensity of HSA, and the system conductivity all first decrease and then increase. The zeta potential of HSA first goes up and then down. The percents of the β-sheet, random, turn structures, and the polarization of HSA increase but the percent of the α-Helix of HSA decreases. When Triton X-100 concentration is more than 1.0×10−3 mol l−1, the structure parameters change obviously especially for the percents of random and turn structures.  相似文献   

7.
Triton X-100增敏光度法测定铝土矿中的微量钪   总被引:1,自引:0,他引:1  
研究了在HCl溶液中微量钪(Ⅲ)-偶氮氯膦Ⅲ(CPAⅢ)之间的配合反应。结果表明,在0.5mol/LHCl溶液中和TritonX 100的存在下,有色溶液的最大吸收波长为680nm,表观摩尔吸光系数为2.62×104L·mol-1·cm-1。钪(Ⅲ)质量浓度在0~0.45mg/L范围内符合比耳定律,钪(Ⅲ)的加标回收率在98.0%~105.1%之间,RSD(n=6)为2.1%~2.6%。可用于铝土矿中的微量钪的测定。  相似文献   

8.
The activity and kinetic characteristics of glucoamylase has been investigated in W/0 microemulsion systems of AOT/isooctane/buffer, CTAB/isooctane/l-pentanol/buffer and TX-100/ibooctane/I-pentanol/buffer, and compared with that in aquous solution. The effect of various parameters, such as pH optimum, To ptimum and water content, on the activity of the enzyme in microemulsion was determined. The results obtained show that the structure of the microemulsion has strong effect on enzyme activity compared to the kcat, in aquous solution, the apparent turnover number k'cat values were decreased in AOT, TX- 100 based system, and in creased in CTAB based system.  相似文献   

9.
研究了以1-(2-吡啶偶氮)-2-萘酚(PAN)为络合剂,以非离子型表面活性刺Triton X-100为萃取剂的浊点萃取分离富集-火焰原子吸收光谱法测定痕量钯的新方法。详细考察了溶液的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效果的影响。该方法对钯的检出限为30.8ng/mL,相对标准偏差(RSD)为2.1%(n=10),回收率在97.8%-106.6%之间。可用于催化剂中Pd(Ⅱ)的测定。  相似文献   

10.
Controlled release of cephanone from hexadecyltrimethylammonium bromide (CTAB) micelles and CTAB/n-C5H11OH/H2O microemulsions was studied. The results showed that the release rate of cephanone was reduced in CTAB micelles and CTAB/n-C5H11OH/H2O microemulsions, because of the solubilization of cephanone in micelles and microemulsions. The release of cephanone from CTAB micelles and CTAB/n-C5H11OH/H2O microemulsions was characterized by Fickian diffusion and non-Fickian diffusion.  相似文献   

11.
质粒DNA的阴离子交换色谱法纯化及内毒素去除   总被引:7,自引:0,他引:7  
采用Fractogel EMD TMAE(M)强阴离子交换介质分离纯化质粒脱氧核糖核酸(DNA),该介质对质粒DNA的动态载样量达0.62 mg/mL。用Triton X-114或Triton X-100预先处理质粒DNA的裂解澄清液后,经阴离子交换色谱分离纯化获得的质粒DNA中内毒素含量分别为6.42 EU/mg和9.50 EU/mg,显著低于未经Triton处理的裂解澄清液(67.82 EU/mg)。该法实现了阴离子交换色谱一步纯化质粒DNA的目的,具有简便、省时、成本低等特点。  相似文献   

12.
The effect of NaCl and HCl on two non-ionic surfactant micelles was studied using several techniques, including conductivity and ion-selective electrodes. Both surfactants exhibit opposite behaviour. When Tween 20 is titrated with HCl the conductivity notably increases in comparison with water, whereas that of Triton X-100 solutions do not change with respect to water until a certain HCl concentration is reached, when it increases. The hydrogen ion activity is lower in Triton X-100 solutions and higher in Tween 20 solutions than in pure water. Chloride ion activity is higher in Tween 20 solutions than in water, whereas in Triton X-100 the activity does not significantly differ from that in water. The activity of sodium ion is lower in Tween 20 solutions than in water, whereas that in Triton X-100 solutions does not differ from the titration of water. These phenomena are explained by the changes in conformation of the non-ionic headgroups, which capture water, and in some cases ions, modifying the activity of ions in the intermicellar solution.  相似文献   

13.
研究了二(2-乙基己基)琥珀酸磺酸钠(AOT)/Triton X-100混合反胶束体系中假丝酵母脂肪酶(candida rugosa lipase)催化蓖麻油水解的反应. 考察了Triton X-100占总表面活性剂的摩尔分数(x(Triton X-100))、水与总体表面活性剂的摩尔比(ω0)、pH值、反应温度以及底物蓖麻油的浓度等因素对酶活性的影响. 研究结果表明, 加入非离子表面活性剂Triton X-100可以使假丝酵母脂肪酶的活性得到显著提高, 但是当底物蓖麻油的浓度大于0.24 mol·L-1时, 会对假丝酵母脂肪酶产生抑制作用.  相似文献   

14.
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   

15.
Employing Triton X-100 as a surfactant, the tert-butyl hydroperoxide-mediated dioxygenation of styrene with molecular oxygen and N-hydroxyphthalimide was achieved in water at room temperature, providing the corresponding dioxygenated products in 9–93% yield. This facile method is eco-friendly, feasible on gram scale, and applicable to a wide range of styrene derivatives with a variety of functional groups.  相似文献   

16.
The present study investigates the effect of different additives on the cloud point (CP) of nonionic surfactants Triton X-100 (TX-100) and Triton X-114 (TX-114) in aqueous solutions. The thermodynamic parameters of these mixtures were calculated at different additive concentrations. The cloud point of nonionic surfactants TX-100 and TX-114 decreased with the increment of electrolyte concentrations and increased with alcohol concentrations. The standard Gibbs free energy was found to be positive for both the surfactants, whereas the enthalpy and the entropy of the clouding phenomenon were found to be positive with alcohols and negative with electrolytes. The overall clouding process was endothermic for alcohols and exothermic for electrolytes.  相似文献   

17.
The effect of Na2SO4 and PhCOONa on the aquation of [Fe(Me4phen)3]2+ has been investigated in pure Triton X-100 as solvent. The rate and mechanism of the aquation are explained in terms of changes in the mobility, activity and structure of H2O in the restricted environment of water pockets in the Triton X-100 solvent.  相似文献   

18.
以布洛芬乙酯为反应底物,探索了酶促水解法拆分布洛芬的工艺。以曲拉通X-100为表面活性剂,利用南极假丝酵母脂肪酶B(CAL-B)催化拆分外消旋布洛芬乙酯,并对表面活性剂含量、有机溶剂种类和添加量、酶量、缓冲溶液pH、温度及时间等反应条件进行了优化;得到的最佳反应条件为:在pH为9.0的缓冲溶液中,添加80 mg曲拉通X-100、50 μL二氯甲烷和15 mg CAL-B,于30℃下反应48 h;在该条件下,S-布洛芬乙酯的剩余率(C)为65%,布洛芬乙酯的对映体过量值(ees)为94%。  相似文献   

19.
Triton X—100—DPSA法测定血铅   总被引:2,自引:0,他引:2  
着重研究了在微分电位溶出法测定血铅中加入TritionX-100非离子型表面活性剂的效果,发现它能改善溶出峰形,减少误差,明显地提高分析的灵敏度,铅溶出峰与浓度在0.002~0.01mg/L范围呈线性关系,回归方程式和相关系数为y=14.57+757.14x,r=1,其相关系数比原法稍有提高,变异系数7.1%,回收率96.8%~103.9%,本法取血量少,血样经微汉消解即可测定,简便快速准确,便基  相似文献   

20.
镁-美他环素胶束体系荧光特性及美他环素的测定   总被引:2,自引:0,他引:2  
研究了在金属离子存在下美他环素在胶柬体系中的荧光特性,实验结果表明:在pH 9.50~11.30的H3PO4-HAc-H3BO3-NaOH缓冲溶液中,镁离子和非离子表面活性剂曲通X-100对美他环素的荧光具有显著的协同增敏作用.据此建立了测定药物制剂中美他环素的荧光光谱法.定量线性范围为0.16~16μg/mL,检出限为0.0036μg/mL,相对标准偏差为1.9%.  相似文献   

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