The preparation and cyclic voltammetric behaviors of self assembled monolayers(SAMs) containing electroactive viologen group have been investigated. neatment of this viologenSAM with solutions of alkanethiols results ...The preparation and cyclic voltammetric behaviors of self assembled monolayers(SAMs) containing electroactive viologen group have been investigated. neatment of this viologenSAM with solutions of alkanethiols results in replacing the electroactive thiol, shifting negativelyits formal potentials and decreasing its heterogeneous electron transfer constants along with theimmersion time. The aim of the work is to understand the exchange regularity of the mired SAMson gold electrode surfaCe.展开更多
The elucidation of key influence factors for electrostatic adsorption is very important to control protein nonspecific adsorption on modified surfaces. In this study, real time surface plasmon resonance technique is u...The elucidation of key influence factors for electrostatic adsorption is very important to control protein nonspecific adsorption on modified surfaces. In this study, real time surface plasmon resonance technique is used to characterize the electrostatic adsorption of two proteins (mouse IgG and protein A) on carboxymethyldextran modified surface. The results show that protein solution pH and ionic strength are key influence factors for efficient electrostatic adsorption. The influence of protein solution pH on the amount of electrostatic adsorption depends on the type of the charge and the charge density of both protein and modified matrix on the surface. The electrostatic adsorption process involves a competition between the positively charged protein and other positively charged species in the buffer solution. A decrease of ionic strength leads to an increasing electrostatic adsorption. The kinetic adsorption constants of protein A at different pH values were also calculated and compared.展开更多
The self assembled monolayer(SAM) of 11 mercaptoundecanoic acid [HS(CH 2) 10 COOH] was formed on a gold electrode and the effect of the charge of end group on the electrochemical response of Fe(CN) 3- 6 at the SAM mod...The self assembled monolayer(SAM) of 11 mercaptoundecanoic acid [HS(CH 2) 10 COOH] was formed on a gold electrode and the effect of the charge of end group on the electrochemical response of Fe(CN) 3- 6 at the SAM modified electrode was studied by cyclic voltammetry. At high pH, when the —COOH groups are dissociated, the current of Fe(CN) 3- 6 is suppressed; as the solution pH is lowered, the current of Fe(CN) 3- 6 increases. The electrochemical titration curve was obtained by correlating the currents of Fe(CN) 3- 6 to the different pH values of electrolyte, from which the surface p K a was obtained to be 3.0±0.2. Furthermore, the reason of small p K a value was explained using SAMs of different surface coverage.展开更多
文摘The preparation and cyclic voltammetric behaviors of self assembled monolayers(SAMs) containing electroactive viologen group have been investigated. neatment of this viologenSAM with solutions of alkanethiols results in replacing the electroactive thiol, shifting negativelyits formal potentials and decreasing its heterogeneous electron transfer constants along with theimmersion time. The aim of the work is to understand the exchange regularity of the mired SAMson gold electrode surfaCe.
文摘The elucidation of key influence factors for electrostatic adsorption is very important to control protein nonspecific adsorption on modified surfaces. In this study, real time surface plasmon resonance technique is used to characterize the electrostatic adsorption of two proteins (mouse IgG and protein A) on carboxymethyldextran modified surface. The results show that protein solution pH and ionic strength are key influence factors for efficient electrostatic adsorption. The influence of protein solution pH on the amount of electrostatic adsorption depends on the type of the charge and the charge density of both protein and modified matrix on the surface. The electrostatic adsorption process involves a competition between the positively charged protein and other positively charged species in the buffer solution. A decrease of ionic strength leads to an increasing electrostatic adsorption. The kinetic adsorption constants of protein A at different pH values were also calculated and compared.
文摘The self assembled monolayer(SAM) of 11 mercaptoundecanoic acid [HS(CH 2) 10 COOH] was formed on a gold electrode and the effect of the charge of end group on the electrochemical response of Fe(CN) 3- 6 at the SAM modified electrode was studied by cyclic voltammetry. At high pH, when the —COOH groups are dissociated, the current of Fe(CN) 3- 6 is suppressed; as the solution pH is lowered, the current of Fe(CN) 3- 6 increases. The electrochemical titration curve was obtained by correlating the currents of Fe(CN) 3- 6 to the different pH values of electrolyte, from which the surface p K a was obtained to be 3.0±0.2. Furthermore, the reason of small p K a value was explained using SAMs of different surface coverage.
