Supramolecular Science最新文献

In this paper, we alternately deposit transition metal Cd²⁺ neutralized polyelectrolytes and ligands pyridine contained polymer via the formation of complexes, and by sequential reaction with H₂S gas, in situ fabricate CdS nanoparticles/polymer heterostructured film. The driving force for the construction of multilayered films is based on covalent coordination.

Three novel amphiphilic phenylazonaphthalenes, namely, 6-(4-(4-octylphenylazo)naphthoxy)hexanoic acid, 6-(4-(4-dodecylphenylazo)naphthoxy)hexanoic acid, 6-(4-(4-hexadecylphenylazo)naphthoxy)hexanoic acid, were synthesized by diazo coupling, etherification and hydrolysis reactions successively. The kinetic studies of the trans–cis isomerization indicated that about 95% of the trans isomers of these compounds in chloroform solutions were transformed to cis isomers under the irradiation of near-ultraviolet light (380±30 nm) observed from UV–Vis spectra. In the dark condition, the cis isomers could reversibly convert to trans isomers following the first-order kinetics at the rates of 4.9×10^-4, 5.7×10^-4, 7.7×10^-4 S^-1, respectively.

We have synthesized a squarylium dye based on 2,6-di-tert-butylpyrylium (full name given in the text). Its nonlinear optical properties was detected by the hyper-Rayleigh light scattering technique in a chloroform solution, although this type of chromophore has a symmetrical structure and a negligible permanent dipole moment. The internal reference method was employed to determine the first hyperpolarizability β value of the chromophore and further discussion is provided.

This study describes the fabrication sequence of a prototype device based on the assembly of copper-tetracyanoquinodimethane (Cu-TCNQ) crystallites in a specially designed and prepared electrode structure. The assembed Cu-TCNQ organometallic salt was synthesized by using the spontaneous electrolysis growth technique. The results of the electrical measurement on this device have clearly shown a typical rectifying characteristic. It is suggested that this rectifying phenomenon is mainly related with the Cu-TCNQ molecular homojuction formed by in-microregion contact.

Sodium 9,10-anthraquinone-2-sulfonate (AQS) binds to the double helical DNA with a high affinity, as deduced from the absorption and fluorescence spectral data. The results of absorption spectra, KI quenching studies, competitive binding studies, and thermal denaturation experiments suggested the intercalative binding of AQS into DNA bases.

A method is described for the coupling of the HBsAb antibody on to a liposome by reverse micelles passing through the modified organic/water interface. Incorporation of the fatty acid modified HBsAb into liposomal membranes was studied as a function of the extent of fatty acid coupling. Results show that the incorporation of HBsAb is proportional to the lipid coupling degree. The HBsAb incorporated into the liposomal membrane by this method remains an antigen binding activity shown by the liposome dialysis assay.

Hydrogenase Langmuir–Blodgett films from Thiocapsa roseopersicina were prepared on gold-coated mica substrates using 20 mer of poly-l-lysine, which stabilizes the enzyme and improves the protein transfer. Scanning tunneling microscopy and intermittent contact mode atomic force microscopy were used to observe the films and to determine that the single hydrogenase–hexagonal complex was laid horizontally to the gold surface. Tunneling spectroscopy of the hydrogenase complex demonstrated the diodelike current-voltage characteristics. The rectification of the tunneling current might be ascribed to the alignment of cofactors, a nickel atom and iron sulfur clusters of the hydrogenase.

Optoelectric properties of a novel liquid crystal zinc tetraphenyltetrabenzoporphyrin (ZnTPTBP) is studied with the aid of surface photovoltaic spectroscopy (SPS) and electric-field-induced SPS. The surface photovoltage response at 550 nm under external field is assigned to the $\text{π–π}{}^{\mathrm{\ast }}$ transmission in the columns of micro π system formed in ZnTPTBP solid film and is thought to be related with the electro-optical memory effect of liquid crystal porphyrin.

In the last decade, molecular electronics, as an active frontier of interdisciplinary research areas, has become one of the most rapidly developing fields, and attracted worldwide interests. The fundamental element of molecular electronics is a molecular device or a supramolecular device, which is an organized molecular system constructed mainly by organic molecules or biomolecules that have some specific functions in signal detection, process, storage, and transmission through chemical or physical interactions at molecular or supramolecular levels. A molecular device (MD) can involve chemical information processes, and be relatively easy to realize a large number of links between the molecules. The links can be controlled by the external signals. These are the expected features of molecular computing and directly involve chemical and biological processes. MD may overcome some limitations of the solid-state chips, and can be directly applied to chemical and biological processes. Molecular electronics is a part of bioelectronics. It will play an important and revolutionary role in the next century. This paper intends to review the research activities of molecular electronics in China, particularly in LMBE.