کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1269418 972453 2006 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Immunosensor interface based on physical and chemical immunoglobulin G adsorption onto mixed self-assembled monolayers
موضوعات مرتبط
مهندسی و علوم پایه شیمی الکتروشیمی
پیش نمایش صفحه اول مقاله
Immunosensor interface based on physical and chemical immunoglobulin G adsorption onto mixed self-assembled monolayers
چکیده انگلیسی
An immunosensor interface based on mixed hydrophobic self-assembled monolayers (SAMs) of methyl and carboxylic acid terminated thiols with covalently attached human Immunoglobulin G (hIgG), is investigated. The densely packed and organised SAMs were characterised by contact angle measurements and cyclic voltammetry. The effect of the non-ionic surfactant, Tween 20, in preventing nonspecific adsorption is addressed by ellipsometry during physical and covalent hIgG immobilization on pure and mixed SAMs, respectively. It is clearly demonstrated that nonspecific adsorption due to hydrophobic interactions of hIgG on methyl ended groups is totally inhibited, whereas electrostatic/hydrogen bonding interactions with the exposed carboxylic groups prevail in the presence of surfactant. Results of ellipsometry and Atomic Force Microscopy, reveal that the surface concentration of covalently immobilized hIgG is determined by the ratio of COOH / CH3-terminated thiols in SAM forming solution. Moreover, the ellipsometric data demonstrates that the ratio of bound anti-hIgG / hIgG depends on the density of hIgG on the surface and that the highest ratio is close to three. We also report the selectivity and high sensitivity achieved by chronoamperometry in the detection of adsorbed hIgG and the reaction with its antibody.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Bioelectrochemistry - Volume 69, Issue 2, October 2006, Pages 180-186
نویسندگان
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