Electrochemistry of didodecyldimethylammonium (DDAB) films containing cobalt phthalocyanine tetrasulfonate (CoPcTS4-) was examined. CoPcTS4--DDAB film electrode showed stable cyclic voltammetric responses in buffers a...Electrochemistry of didodecyldimethylammonium (DDAB) films containing cobalt phthalocyanine tetrasulfonate (CoPcTS4-) was examined. CoPcTS4--DDAB film electrode showed stable cyclic voltammetric responses in buffers and could catalyze reductions of trichloroacetic acid.展开更多
Quaternaryammonium compounds (QACs) are cationic surfactants with broad range applications. They enter into aquatic environment through the discharge of sewage effluents and adversely affect the ecosystem due to toxic...Quaternaryammonium compounds (QACs) are cationic surfactants with broad range applications. They enter into aquatic environment through the discharge of sewage effluents and adversely affect the ecosystem due to toxicity. Modern electrochemical methods have been used for characterization and detoxification of an extensively used QAC, didodecyldimethylammonium bromide (DDAB) in a wide pH range. The diffusion coefficient of DAAB was determined by Randles-Sevcik equation. In acidic conditions the electrochemical reduction of DAAB occurred by two electrons and two protons process. However, in neutral medium the overall reduction of DAAB followed electronation-protonation mechanism involving 3e– and 3H+. Although DDAB is toxic yet it is bestowed with cancer preventing ability. Hence, for getting insights into the under-standing of DAAB anticancer effect, its DNA binding parameters has been evaluated.展开更多
The vesicle of didodecyldimethylammonium bromide (DDAB) which containedtetrathiafulvalene (TTF) was mixed with xanthine oxidase, and the mixture was cast on the pyrolyticgraphite electrode. The lipid films were used t...The vesicle of didodecyldimethylammonium bromide (DDAB) which containedtetrathiafulvalene (TTF) was mixed with xanthine oxidase, and the mixture was cast on the pyrolyticgraphite electrode. The lipid films were used to supply a biological environment resemblingbiomembrane on the surface of the electrode. TTF was used as a mediator because of its highelectron-transfer efficiency. A novel xanthine biosensor based on cast DDAB film was developed. Theeffects of pH and operating potential were explored for optimum analytical performance by using theamperometric method. The response time of the biosensor was less than 10 s. The detection limit ofthe biosensor was 3.2 x 10^(-7) mol/L and the liner range was from 4 x 10^(-7) mol/L to 2.4 x10^(-6) mol/L.展开更多
Stable thin films made from polyionic complex 2C12N+PVS- with incorporated Hb on PG electrodes were characterized by electrochemistry. The electron transfer between Hb and PG electrodes was greatly facilitated in micr...Stable thin films made from polyionic complex 2C12N+PVS- with incorporated Hb on PG electrodes were characterized by electrochemistry. The electron transfer between Hb and PG electrodes was greatly facilitated in microenvironment of 2C12N+PVS- films. The Hb-2C12N+PVS-films could be used to catalytically reduce trichloroacetic acid.展开更多
Ordered films were made by casting a mixture of aqueous dispersions of didodecyldimethylammonium bromide (DDAB)-clay composite and myoglobin (Mb) solution on pyrolytic graphite (PG) electrodes. The Mb-DDAB-clay film e...Ordered films were made by casting a mixture of aqueous dispersions of didodecyldimethylammonium bromide (DDAB)-clay composite and myoglobin (Mb) solution on pyrolytic graphite (PG) electrodes. The Mb-DDAB-clay film electrodes showed stable and reversible cyclic voltammetric responses in buffers and can catalyze the reduction of id (TCA).展开更多
The vesicle structures of egg yolks phosphatidylcholine/didodecyldimethylammonium bromide （1 ： 1, mass ratio） deposited on mica were studied by atomic force microscopy （AFM） both in aqueous phase and air. In aque...The vesicle structures of egg yolks phosphatidylcholine/didodecyldimethylammonium bromide （1 ： 1, mass ratio） deposited on mica were studied by atomic force microscopy （AFM） both in aqueous phase and air. In aqueous phase both bilayer and domelike vesicles with a mean diameter of 45 nm were observed, whereas in air the structure was more complicated depending on the initial concentration of vesicles. Vesicles with the original size could only be visualized at very low concentration with a mean diameter of 55 nm, which is a little larger than the result obtained in aqueous phase. At higher concentrations, fused large aggregates and multiple bilayer with a thickness ca. 4 nm of each bilayer were dominated. A plausible adsorption mechanism was proposed based on the experimental results.展开更多
文摘Electrochemistry of didodecyldimethylammonium (DDAB) films containing cobalt phthalocyanine tetrasulfonate (CoPcTS4-) was examined. CoPcTS4--DDAB film electrode showed stable cyclic voltammetric responses in buffers and could catalyze reductions of trichloroacetic acid.
文摘Quaternaryammonium compounds (QACs) are cationic surfactants with broad range applications. They enter into aquatic environment through the discharge of sewage effluents and adversely affect the ecosystem due to toxicity. Modern electrochemical methods have been used for characterization and detoxification of an extensively used QAC, didodecyldimethylammonium bromide (DDAB) in a wide pH range. The diffusion coefficient of DAAB was determined by Randles-Sevcik equation. In acidic conditions the electrochemical reduction of DAAB occurred by two electrons and two protons process. However, in neutral medium the overall reduction of DAAB followed electronation-protonation mechanism involving 3e– and 3H+. Although DDAB is toxic yet it is bestowed with cancer preventing ability. Hence, for getting insights into the under-standing of DAAB anticancer effect, its DNA binding parameters has been evaluated.
文摘The vesicle of didodecyldimethylammonium bromide (DDAB) which containedtetrathiafulvalene (TTF) was mixed with xanthine oxidase, and the mixture was cast on the pyrolyticgraphite electrode. The lipid films were used to supply a biological environment resemblingbiomembrane on the surface of the electrode. TTF was used as a mediator because of its highelectron-transfer efficiency. A novel xanthine biosensor based on cast DDAB film was developed. Theeffects of pH and operating potential were explored for optimum analytical performance by using theamperometric method. The response time of the biosensor was less than 10 s. The detection limit ofthe biosensor was 3.2 x 10^(-7) mol/L and the liner range was from 4 x 10^(-7) mol/L to 2.4 x10^(-6) mol/L.
文摘Stable thin films made from polyionic complex 2C12N+PVS- with incorporated Hb on PG electrodes were characterized by electrochemistry. The electron transfer between Hb and PG electrodes was greatly facilitated in microenvironment of 2C12N+PVS- films. The Hb-2C12N+PVS-films could be used to catalytically reduce trichloroacetic acid.
文摘Ordered films were made by casting a mixture of aqueous dispersions of didodecyldimethylammonium bromide (DDAB)-clay composite and myoglobin (Mb) solution on pyrolytic graphite (PG) electrodes. The Mb-DDAB-clay film electrodes showed stable and reversible cyclic voltammetric responses in buffers and can catalyze the reduction of id (TCA).
基金Project supported by the National Natural Science Foundation of China （No. 20573079）, The authors are grateful to Prof. Daiwen PANG and Dr. Zhexue LU of Department of Chemistry of Wuhan University, Wuhan, for their kindly help in the AFM measurements.
文摘The vesicle structures of egg yolks phosphatidylcholine/didodecyldimethylammonium bromide （1 ： 1, mass ratio） deposited on mica were studied by atomic force microscopy （AFM） both in aqueous phase and air. In aqueous phase both bilayer and domelike vesicles with a mean diameter of 45 nm were observed, whereas in air the structure was more complicated depending on the initial concentration of vesicles. Vesicles with the original size could only be visualized at very low concentration with a mean diameter of 55 nm, which is a little larger than the result obtained in aqueous phase. At higher concentrations, fused large aggregates and multiple bilayer with a thickness ca. 4 nm of each bilayer were dominated. A plausible adsorption mechanism was proposed based on the experimental results.
