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1.
胆酸盐是一类生物表面活性剂, 一般含有羟基取代的类固醇骨架, 并有一带负电的尾链, 较为常见的胆酸盐有胆酸钠、 脱氧胆酸钠、 牛磺胆酸钠及牛磺脱氧胆酸钠等. 其分子结构见表1及图1所示. 相似文献
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选用牛磺脱氧胆酸钠和脱氧胆酸钠等6种胆酸类表面活性剂,考察其对单壁碳纳米管(SWCNTs)的分散能力.紫外-可见-近红外吸收光谱测试结果表明,在超声功率为225 W,超声时间1 h的分散条件下,胆酸类表面活性剂均能对SWCNTs均匀分散,均可作为SWCNTs的分散剂.在相同条件下,质量分数为2%的牛磺脱氧胆酸钠对SWCNTs的分散能力最强,脱氧胆酸钠对SWCNTs的分散能力最弱.此外,还采用聚乙二醇/葡聚糖双水相系统对SWCNTs分散液进行了萃取分离,获得了纯度较高的手性SWCNTs(6,5).所筛选的SWCNTs分散剂及采用的双水相分离方法为单一手性SWCNTs的分离提供了一定的技术参考. 相似文献
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胆酸盐在酸性介质中自聚集作用的共振瑞利散射光谱及其分析应用研究 总被引:3,自引:0,他引:3
研究了牛磺胆酸钠、甘牛胆酸钠、胆酸钠和脱氧胆酸钠等四种胆酸盐在酸性介质中的聚集作用对共振瑞利散射光谱的影响及其分析应用. 结果表明: 在一定浓度的HCl, H2SO4或HNO3溶液中, 四种胆酸盐均能自聚集形成粒径增大的聚集体. 该聚集体能导致溶液RRS显著增强, 并产生了新的RRS光谱. 不同胆酸盐在同种介质中的反应产物具有相似的光谱特征, 最大RRS波长分别位于349 (HNO3介质), 359 (H2SO4介质)和369 nm (HCl介质). 在一定范围内, 胆酸盐的浓度与散射强度(ΔIRRS)成正比. 对于不同的体系其检出限在12.0~21.8 ng/mL之间. 方法灵敏度高, 选择性较好, 而且十分简便快速. 可用于市售蛇胆川贝液和血清样品中胆酸盐的测定. 相似文献
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牛磺胆酸钠对胆红素与钙离子相互作用形成沉淀过程的影响的研究 总被引:1,自引:1,他引:1
本工作选择牛磺胆酸钠作为人体内胆汁酸盐的代表研究其对胆色素结石的重要成分——胆红素钙沉淀过程的影响。结果表明,牛磺胆酸钠的存在使胆红素钙沉淀的条件溶度积大大提高,并使沉淀反应速度大大减慢。在牛磺胆酸钠浓度较高的情况下,沉淀过程出现诱导期,说明牛磺胆酸钠在一定条件下可以抑制胆红素钙沉淀的形成。沉淀的红外光谱表明,牛磺胆酸并未结合在沉淀中,也未影响沉淀中胆红素与钙离子间的相互作用的部位。沉淀的扫描电镜观察结果经统计学处理表明牛磺胆酸钠的存在使沉淀的颗粒变小,颗粒的聚集程度减小。 相似文献
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应用基于超高效液相色谱-串联质谱(UPLC-MS/MS)技术的代谢组学方法检测2型糖尿病患者血清胆汁酸代谢谱,获得代谢标志物,发掘可预测糖尿病的潜在预防治疗靶点。采用Waters ACQUITY UPLC BEH C18色谱柱(150 mm×2.1 mm,1.7 μm)分离,0.05%乙酸水溶液-乙腈为流动相,以0.40 mL/min流速进行梯度洗脱,用此方法测定了30例糖尿病患者和 50例正常人血清胆汁酸代谢谱。41种胆汁酸标准品在30 min内均得到良好分离,各成分在一定浓度范围内呈良好线性关系,检出限(LOD)为0.24~7.81 nmol/L,定量下限(LOQ)为0.49~15.63 nmol/L,相关系数(r2)为 0.986 7~0.999 7。血清中胆汁酸代谢谱与两组间存在相关性,通过正交偏最小二乘法-判别分析(OPLS-DA)发现,有12种胆汁酸(包括甘氨熊脱氧胆酸、甘氨胆酸、牛磺鹅脱氧胆酸、胆酸、熊去氧胆酸、甘氨鹅脱氧胆酸、甘氨脱氧胆酸、12 酮基石胆酸、鹅脱氧胆酸、脱氧胆酸、异石胆酸、石胆酸)承载了分组的重要信息。结合受试者工作特征(ROC)分析,最终获得牛磺鹅脱氧胆酸(AUC=0.68)、甘氨鹅脱氧胆酸(AUC=0.66)、甘氨熊脱氧胆酸(AUC=0.63)、胆酸(AUC=0.63)、脱氧胆酸(AUC=0.63)、甘氨脱氧胆酸(AUC=0.58) 6种胆汁酸代谢标志物,对于糖尿病的早期诊断及深入研究具有潜在的科研及临床价值。 相似文献
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在阴离子表面活性剂十二烷基苯磺酸钠(SDBS)体系中,采用一步法制得聚苯胺/SDBS超疏水复合材料.利用场发射扫描电子显微镜(FESEM)观察产物形貌并测定其元素组成.通过傅里叶变换红外光谱仪、紫外-可见光谱仪、X射线衍射等对其结构进行表征,用视频接触角测量仪测定材料的亲疏水性.考察SDBS浓度和溶液酸度对产物形貌及疏水性能的影响,探讨疏水机理.结果表明:在pH=1-9,SDBS浓度大于0.016 mol?L-1条件下,所制备复合材料的水接触角大于150°,SDBS掺杂使得苯胺单体的转化率高达98%.两亲分子SDBS亲水磺酸基与聚苯胺主链上的亚胺基不仅存在静电引力,而且能形成磺酰胺键,聚苯胺主链间又以氢键相互连接,SDBS分子的疏水烃基有序排列朝向聚苯胺主链外侧,从而组装形成具有微纳结构的聚苯胺/SDBS超疏水复合材料.本文结果有利于更好地理解聚苯胺/SDBS超疏水性复合材料的形成机理,对超疏水材料的设计提供新思路. 相似文献
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《物理化学学报》2014,(3)
在阴离子表面活性剂十二烷基苯磺酸钠(SDBS)体系中,采用一步法制得聚苯胺/SDBS超疏水复合材料.利用场发射扫描电子显微镜(FESEM)观察产物形貌并测定其元素组成.通过傅里叶变换红外光谱仪、紫外-可见光谱仪、X射线衍射等对其结构进行表征,用视频接触角测量仪测定材料的亲疏水性.考察SDBS浓度和溶液酸度对产物形貌及疏水性能的影响,探讨疏水机理.结果表明:在pH=1-9,SDBS浓度大于0.016 mol?L-1条件下,所制备复合材料的水接触角大于150°,SDBS掺杂使得苯胺单体的转化率高达98%.两亲分子SDBS亲水磺酸基与聚苯胺主链上的亚胺基不仅存在静电引力,而且能形成磺酰胺键,聚苯胺主链间又以氢键相互连接,SDBS分子的疏水烃基有序排列朝向聚苯胺主链外侧,从而组装形成具有微纳结构的聚苯胺/SDBS超疏水复合材料.本文结果有利于更好地理解聚苯胺/SDBS超疏水性复合材料的形成机理,对超疏水材料的设计提供新思路. 相似文献
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1-溴萘——β-环糊精——阴离子表面活性剂三元包合物的室温磷光 总被引:8,自引:0,他引:8
在β-环糊精(β-CD)溶液中, 加入阴离子表面活性剂(AS)可诱导1-溴萘(1-BrN)发射强的室温磷光(RTP)。组成测定表明溶液中形成了稳定的1:1:1/1-BrN:β-CD:AS三元包合物。光谱和溶液表面张力分析显示阴离子表面活性剂的疏水性烷基链有一部分被包合在β-CD空腔内, 未被包合部分则绕曲在β-CD腔口处从而为空腔内1-BrN分子的磷光提供了有效保护。因该三元包合物带有阴离子极性头基, 其沉淀可均匀分散在溶液中, 形成了稳定的乳状液。得到了稳定的RTP。 相似文献
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β-环糊精存在下直链脂肪醇诱导1-溴萘室温磷光光谱研究 总被引:1,自引:0,他引:1
研究了β-环糊精(β-CD)溶液中直链脂肪醇(A)诱导1-溴萘(1-BrN)的室温磷光光谱性质.结果表明,三元包络物中1-BrN分子的磷光起初随醇中碳原子数的增加而增强,正戊醇对磷光呈现最大的敏化作用,随后从正己醇至正辛醇,磷光强度逐渐下降.测定了包络物组成和稳定常数,发现1-BfN和A:β-CD包络物的结合强度是三元包络物磷光强弱的决定性因素,并从三元包络物可能的结构解释了醇分子大小对室温磷光的影响. 相似文献
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YONG Zhang YUAN Dong-Xing ZHU Ya-Xian DU Xin-Zhen HUANG Xian-Zhi JIA Ping-Fu 《高等学校化学学报》1999,20(Z1):556
The Room-Temperature-Phosphorescence (RTP) of α-bromonaphthalene (α-BrNp) induced by different kinds of surfactants in aqueous solution of β-Cyclodextrin (β-CD) have been studied. 相似文献
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Room temperature phosphorescence (RTP) of three palladium (Pd)-phorphyrins in air-saturated solution of sodium deoxycholate (NaDC) aggregates was measured. RTP of Pd-meso-tetrakis (4-carboxyphenyl) porphyrin (Pd-TCPP) was obviously enhanced in NaDC-aggregates mediated by alkaline earth metal (AEM). Under the same experimental conditions, Ca(2+), Ba(2+) and Mg(2+) induced 200, 90 and 24 times greater enhancement in RTP of Pd-TCPP, respectively. It is ascribed to form the complex of NaDC-aggregate/AEM/Pd-TCPP in the system. The positively charged AEM has a strong capability of co-ordination with negatively charged carboxyl groups of NaDC and Pd-TCPP. The phosphor Pd-TCPP is confined in rigid NaDC-aggregates/AEM system by the coordination which decreases the probability of collision of phosphor with quenchers such as dissolved oxygen molecules and prolongs the lifetime of the phosphor on the triplet state. Long excited-state lifetimes resulted in great enhancement of Pd-TCPP phosphorescence. Observations by optical microscope showed that specific fan-like structures of NaDC were formed under the influence of AEM. Surface tension measurements supported a close interaction between Ca(2+) ions and anion aggregates of NaDC with 1:1 stoichiometric ratio. Due to its outstanding RTP behavior in NaDC-aggregates induced by Ca(2+), Pd-TCPP was used as a RTP probe to detect bovine serum albumin (BSA). A broad linear range from 1.0 × 10(-9) to 9.0 × 10(-7) g mL(-1) was obtained. Detection limit is 2.6 × 10(-11) g mL(-1), the relative standard deviation (n = 6) is 2.3% for 2.0 × 10(-9) g mL(-1) BSA. 相似文献
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Intense room temperature phosphorescence of 1-bromonaphthalene (1-BrN) induced by p-octylpolyethylene glycol phenylether was studied in aqueous beta-cyclodextrin solution. The mode of inclusion complex formation was approached. The optimal conditions were obtained. Interferences of foreign substances with phosphorescence were examined. The phosphorescence intensity is proportional to the concentration of 1-BrN in the range 0 approximately 5.18 mug ml(-1). The recovery is 90-102% and the relative standard deviation is less than 4.5%. The proposed method is simple and convenient. 相似文献
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Owing to the physiological importance of the micellization process of bile salts, the critical micelle concentration (CMC) becomes a fundamental parameter in the evaluation of their biological activities. The present study suggests fluorescence probing, using 1,6-diphenylhexatriene (DPH), as a simple, convenient, sensitive and economic method for monitoring the micellization process of bile salts in aqueous medium. Three independent parameters: fluorescence intensity, anisotropy and lifetime of DPH have been employed successfully for determining the CMC of two bile salts, sodium deoxycholate (NaDC) and sodium cholate (NaC), in aqueous medium. The CMC values reported by all the above three parameters of DPH are found to be same and it is 16 mM for NaC and 6 mM for NaDC at 25 degrees C in unbuffered solution. The effect of temperature and ionic strength on the micellization process has also been investigated employing DPH as a fluorescent probe. Increasing temperature leads to the formation of fluffier micelles with less rigid interior for both NaC and NaDC. The micelle core of NaC is less perturbed by the presence of NaCl whereas in case of NaDC, the aggregates provide DPH a more nonpolar and rigid environment in presence of NaCl than that in absence of salt. 相似文献
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建立了α-溴代萘的β-环糊精诱导室温磷光(β-CD-RTP)分析,用3因素、3水平Box-Behnken响应面法(RSM)优化了影响α-溴代萘的RTP实验条件。研究发现:β-CD的浓度、环己烷浓度以及Na_2SO_3浓度等对α-溴代萘的RTP强度均有显著影响;统计结果显示各影响因素的主效应关系为:β-CD浓度NaSO_3浓度环己烷用量。α-溴代萘RTP最佳发光条件为:β-CD的浓度为3.4×10~(-3) mol/L,环己烷的浓度为0.8μL/mL,Na_2SO_3的浓度为9.5×10~(-2) mol/L。优化条件下改进了α-溴代萘RTP分析特性,该方法的线性范围为8.0×10~(-5)~1.0×10~(-7) mol/L,检出限为1.4×10~(-8) mol/L。RSM法与传统的单因素实验法相比,有较宽的线性范围和较低的检出限。 相似文献
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Peng YL Jin WJ Feng F 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(13-14):3038-3042
Effect of five cyclic third components, cyclohexane, methylcyclohexane, perfluorocyclohexane, perfluoromethylcyclohexane and adamantane, on cyclodextrin-induced room-temperature phosphorescence (CD-RTP) of 1-bromonaphthalene is studied. It is found that these five compounds can induce intensive RTP, and the enhancement order is as follows: cyclohexane>adamantane>methylcyclohexane>perfluorocyclohexane>perfluoromethylcyclohexane. Dependence of RTP intensity on temperature of these systems shows the potential application in developing optical thermometer. 相似文献
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合成了α-环糊精(α-CD)修饰的有机聚合整体材料,对合成的材料进行了表征,研究比较了α-CD修饰整体材料作为室温磷光固体基质的效果以及14种有机化合物在其上的室温磷光分析(RTP)行为。 α-CD修饰的有机聚合整体材料背景干扰低, 对二环芳烃类物质有较好的选择性和富集能力。 在α-CD修饰膜上,萘和7,8苯并喹啉的分配常数分别为5.03×103和2.94×102,表明修饰材料对萘有较好的选择性。 萘酚也能与修饰材料形成包络物。 但是由于较强的极性和在水中的溶解性,不能被有效富集。 对5.0×10-11 mol/mL萘,最大富集体积为300 mL。 采用SPE-RTP,萘和7,8苯并喹啉的检出限分别为9.80×10-12和4.60×10-11 mol/mL,RSD小于3.7%;线性范围分别为5.00×10-11~8.00×10-9 mol/mL和6.00×10-11~5.00×10-10 mol/mL。 应用修饰的膜片对土样中的萘进行选择性富集和测定,结果由GC-MS进一步确认。 用环己烷一步提取和SPE-RTP测定,萘可以被选择性富集。 在土壤样品中加萘标准0.012 8 mg,测得回收率(104.9±6.5)%。 土样中萘的浓度为(5.61±0.12) mg/kg,与GC-MS的较为吻合。 相似文献
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Photocontrolled reversible room temperature phosphorescence (RTP) emission engendered by the complexation of β-cyclodextrin (β-CD) and α-bromonaphthalene (α-BrNp) can be employed to address the threading and dethreading of the pseudorotaxane formed between β-CD and sodium 2-hydroxy-5-((4-nitrophenyl)diazenyl)benzoate (DAYR) in the ternary system in aqueous solution. 相似文献