A Gold surface was modified with N acetylcysteine to produce a self assembled monolayer and then a single layer film of rabbit IgG was immmobilized on modified gold surface covalently using carbodiimide hydrochloride(...A Gold surface was modified with N acetylcysteine to produce a self assembled monolayer and then a single layer film of rabbit IgG was immmobilized on modified gold surface covalently using carbodiimide hydrochloride(EDC) and N hydroxysuccinimide(NHS). The competitive method(Ⅰ), the sandwich method(Ⅱ) and the surplus method(Ⅲ) were developed to determine rabbit IgG or goat anti rabbit IgG, respectively. A luminescence analyzer connected with a fluorescence microscope was employed to detect the light intensity of labeled sheep anti rabbit IgG. The results of sensitivity and dynamic range were obtained as 25 mg/L and 25—600 mg/L for method(Ⅰ), 1 0 mg/L and 1—200 mg/L for method(Ⅱ) and 25 mg/L and 25—500 mg/L for method(Ⅲ), respectively.展开更多
The electrochemical behavior of zinc(Ⅱ) ion at self assembled modified gold electrodes with L cysteine was investigated.Cys/SAM/Au showed excellent electrocatalytic activity for the reduction of zinc(Ⅱ) ion.In a B R...The electrochemical behavior of zinc(Ⅱ) ion at self assembled modified gold electrodes with L cysteine was investigated.Cys/SAM/Au showed excellent electrocatalytic activity for the reduction of zinc(Ⅱ) ion.In a B R buffer solution(pH 7.45),a sensitive reduction peak of zinc(Ⅱ) ion was observed with Cys/SAM/Au.The peak potential was 0.02V(vs.SCE).The peak current of zinc(Ⅱ) ion on Cys/SAM/Au was proportional to the concentration of zinc(Ⅱ) ion between 1.5×10 -9 and 1.5×10 -6 mol·L -1 .The detection limit was 1.5×10 -10 mol·L -1 .This method was used to analyze human hair samples with satisfied results.展开更多
The role of self assembled monolayer in inducing the crystal growth was investigated by X ray diffractions (XRD), and scanning electron microscopy (SEM). Results show that crystallization in the absence of monolayer r...The role of self assembled monolayer in inducing the crystal growth was investigated by X ray diffractions (XRD), and scanning electron microscopy (SEM). Results show that crystallization in the absence of monolayer results in a mixture of poorly crystallized calcium phosphates, including hydroxyapatite (HAP) and octacalcium phosphate (OCP), while the presence of self assembled monolayer gives rise to oriented and well crystallized HAP crystals. Moreover, the HAP crystal grows very quickly under the self assembled monolayer, whereas very little calcium phosphate crystals grow without the monolayer. It is rationalized that the hexadecylamine monolayer with high polarity and charged density leads to increase supersaturation and lower the interfacial energy, which attributes to the HAP crystals nucleation. On the other hand, the positive headgroups construct the ordered "recognized site" with distinct size and topology, which results in the oriented HAP crystals deposit.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A Gold surface was modified with N acetylcysteine to produce a self assembled monolayer and then a single layer film of rabbit IgG was immmobilized on modified gold surface covalently using carbodiimide hydrochloride(EDC) and N hydroxysuccinimide(NHS). The competitive method(Ⅰ), the sandwich method(Ⅱ) and the surplus method(Ⅲ) were developed to determine rabbit IgG or goat anti rabbit IgG, respectively. A luminescence analyzer connected with a fluorescence microscope was employed to detect the light intensity of labeled sheep anti rabbit IgG. The results of sensitivity and dynamic range were obtained as 25 mg/L and 25—600 mg/L for method(Ⅰ), 1 0 mg/L and 1—200 mg/L for method(Ⅱ) and 25 mg/L and 25—500 mg/L for method(Ⅲ), respectively.
文摘The electrochemical behavior of zinc(Ⅱ) ion at self assembled modified gold electrodes with L cysteine was investigated.Cys/SAM/Au showed excellent electrocatalytic activity for the reduction of zinc(Ⅱ) ion.In a B R buffer solution(pH 7.45),a sensitive reduction peak of zinc(Ⅱ) ion was observed with Cys/SAM/Au.The peak potential was 0.02V(vs.SCE).The peak current of zinc(Ⅱ) ion on Cys/SAM/Au was proportional to the concentration of zinc(Ⅱ) ion between 1.5×10 -9 and 1.5×10 -6 mol·L -1 .The detection limit was 1.5×10 -10 mol·L -1 .This method was used to analyze human hair samples with satisfied results.
文摘The role of self assembled monolayer in inducing the crystal growth was investigated by X ray diffractions (XRD), and scanning electron microscopy (SEM). Results show that crystallization in the absence of monolayer results in a mixture of poorly crystallized calcium phosphates, including hydroxyapatite (HAP) and octacalcium phosphate (OCP), while the presence of self assembled monolayer gives rise to oriented and well crystallized HAP crystals. Moreover, the HAP crystal grows very quickly under the self assembled monolayer, whereas very little calcium phosphate crystals grow without the monolayer. It is rationalized that the hexadecylamine monolayer with high polarity and charged density leads to increase supersaturation and lower the interfacial energy, which attributes to the HAP crystals nucleation. On the other hand, the positive headgroups construct the ordered "recognized site" with distinct size and topology, which results in the oriented HAP crystals deposit.
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.
