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Structural Effects on the langmuir monolayers of Calix[4]arene Induced by Lower Rim Aromatic Substitution

Chinese Journal of Chemistry 2006年第6期24卷 800-806页

作者：何卫江邱琳李峻柏张宇郭子建朱龙根 State Key Laboratory of Coordination Chemistry Nanjing University Nanjing Jiangsu 210093 China International Joint Laboratory the Center for Molecular Science Institute of ChemistryChinese Academy of Sciences Beijing 100080 China Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials Huaiyin Teachers College Huaian Jiangsu 223300 China

The langmuir monolayer properties of lower rim aromatically substituted calix[4]arenes, 5,11,17,23-tetra-tert-butyl-25,27-bis（2-naphth-1＇-ylacetylaminoethoxy）-26,28-dihydroxylcalix[4]arene （BNAEC）, 5,11,17,23-tetra-tert- butyl-25,27-bis（2-benzoylamino ethoxy）-26,28-dihydroxylcalix[4]arene （BBAEC） and 5,11,17,23-tetra-tert-butyl- 25,27-bis（2-cinnamoylaminoethoxy）-26,28-dihydroxylcalix[4]arene （BCAEC）, have been studied. Film balance measurements and Brewster angle microscopy （BAM） observation demonstrate that all the compounds can form langmuir monolayers with different molecular limiting areas. BNAEC or BBAEC monolayer is able to form condensed domains during compression, while BCAEC monolayer can never form condensed domain. BNAEC monolayer is more readily to form condensed domain than BBAEC monolayer. Moreover, BNAEC monolayer can form the total condensed phase during compression even when T=28℃, while BBAEC monolayer can not when T 〉 10 ℃. The results imply that different lower rim aromatic substitutions affect essentially the intermolecular interaction and molecular packing in the monolayer at air/water interface.

关键词： langmuir monolayer calixarene condensed domain Brewster angle microscopy

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SYNTHESIS OF AMPHIPEILIE TEMPO DERIVATIVE AND CHARACTERIZATION OF langmuir monolayerS OF AMPHIPHILIC ALKYL-TEMPOS AT THE AIR/WATER INTERFACE

SYNTHESIS OF AMPHIPEILIE TEMPO DERIVATIVE AND CHARACTERIZATI...

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Asia Conference on Nanoscience and Nanotechnology Abstracts Book

作者： SOO JA SHIN YOUNG SOO KANG Department of Chemistry Pukyong National University Busan 608-737 Korea Department of Chemistry Pukyong National University Busan 608-737 Korea

＜正＞ The amphiphilic TEMPO molecules consist of two dissimilar parts. One part is hydrophilic（bead） and the rest part is hydrophobic（tail）. The derivatives of 4-alkaneamino-2,2,6,6-tetramethyl-1-piperidinyloxy radical （C12-amino-TEMPO） was synthesized with 4-amino-TEMPO and carboxylic acid. The C12-amino-TEMPOs equilibrated at the air/water interface form langmuir monolayer by classical langmuir monolayer techniques. The stable monolayers of C14-22-amino-TEMPOs were characterized by pressure-area isotherms. The features ofcollapse pressure of C14-22-amino-TEMPOs were confirmed on alkyl chain length. Limiting area points and take-off area points from surface pressure-MMA isotherms were subjected to the influence of subphase. The monolayers of C22-amino-TEMPO which has longer alkyl chain were characterized by Brewster Angle Microscopy. So we can confirm phase transition by BAM images as monolayer is expanding at the roomtemperature.

关键词： langmuir monolayer BAM TEMPO.

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Mapping the structure-activity relationship of β-sitosteryl fatty acid esters in condensing phospholipid monolayers

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Frontiers of Chemical Science and Engineering 2015年第1期9卷 105-113页

作者： Worawan PANPIPAT Hasene KESKIN Zheng GUO Department of Engineering Faculty of Science Aarhus University Gustav Wieds Vej 10 8000 Aarhus C Denmark Department of Food Engineering Faculty of Engineering University of Gaziantep 27310 Gaziantep Turkey

Abstract The phase behavior of twelve synthesized β- sitosteryl fatty acid esters with acyl moieties with different chain lengths （C2：0-C18：0） and different degrees of unsaturation （C18：1-C18：3） were investigated in pure and mixed langmuir monolayers with phospholipids. The surface-pressure isotherms showed that short chain fl- sitosteryl fatty acid esters gave smaller mean molecular areas and had decreased monolayer stability and the long chain steryl esters did not produce collapsed plateaus. All the steryl esters displayed strong condensing effects, but there was a pronounced structural dependency： medium chain esters （C8 and C 10） were less efficient than short and long chain esters. Atomic force microscopy imaging demonstrated that monolayers mixed with dipalmitoyl phosphatidylcholine （DPPC） displayed both DPPC-rich and steryl lipid-rich domains. However, the height and area differences between the two phases and the roughness and morphologic patterns were very dependent on the steryl lipid concentrations as well as the length, the degree of unsaturation and the molecular conformations of the acyl segments. These findings not only provide a better understanding of the interactions between phytosteryl hydrophobic derivatives and biomembranes, but also may be of general use for the design and engineering of phytosterol structural derivations for specific food and pharmaceutical applications.

关键词： β-sitosteryl fatty acid esters dipalmitoylphosphatidylcholine langmuir monolayer condensingeffect structure-activi .ty relationship

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Ordered supramolecular assembly of bis[3,4,12,13,21,22,30,31-octa(dodecylthio)-2,3-naphthalocyaninato]erbium at the air/water interface

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Science China Chemistry 2001年第6期44卷 650-656页

作者：陈艳丽刘洪国潘娜张宪玺刘伟程传福姜建壮 Department of Chemistry Shandong University Jinan China Department of Chemistry Jinan University Jinan China Key Laboratory for Colloid and Interface Chemistry of the Ministry of Education Shandong University Jinan China Department of Physics Shandong Normal University Jinan China

The supramolecular assembly of bis[3, 4, 12, 13, 21, 22, 30, 31-octa(dodecylthio)-2, 3-naphthalocyaninato] erbium complex (Er[Nc(SC12H25)8]2) was fabricated at the air/water interface by langmuir monolayer technique. Surface pressure-area isotherm indicates that stable monolayer is formed. The monolayer morphology on mica was investigated by atomic force microscopy (AFM). Columnar domains of ca. 100 nm X (20–30) nm appearing in the micrograph have ordered orientation. Polarized UV-vis spectra and small-angle X-ray diffraction pattern show that the macrocycles tilt in the monolayer. The orientation angle of the naphthalocyanine ring with respect to the substrate was found to be ca. 54°. Each monolayer is ca. 3.53 nm thick. The columnar domain comprises 4–6 rows of columnar supramolecular assemblies where the molecules stack face-to-face.

关键词： bis(naphthalocyaninato) erbium langmuir monolayer supramolecular assembly

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