کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9743732 1491198 2005 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Femtomolar immunoassay based on coupling gold nanoparticle enlargement with square wave stripping voltammetry
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Femtomolar immunoassay based on coupling gold nanoparticle enlargement with square wave stripping voltammetry
چکیده انگلیسی
The enhancement in sensitivity for an electrochemical immunoassay by the autocatalytic deposition of Au3+ onto gold nanoparticles has been studied. By coupling the autocatalytic deposition with square-wave stripping voltammetry, enlarged gold nanoparticles labeled on goat anti-rabbit immunoglobulin G (GaRIgG-Au) and, thus, the rabbit immunoglobulin G (RIgG) analyte could be determined quantitatively. A variety of variables, such as concentration of AuCl4−, the reducing agent used, the duration of autocatalytic deposition, and parameters for the stripping analysis were optimized. From a calibration graph over a broad dynamic range of concentrations (1-500 pg mL−1; R2 = 0.9975) a very low detection limit, 0.25 pg mL−1 (1.6 fM), which is three orders of magnitude lower than that obtained by a conventional immunoassay using the same gold nanoparticle labels was obtained; this finding confirms applicability and effectiveness of our method of enhancing the sensitivity of gold nanoparticle label-based sandwich immunoassays. The reliability of this method was confirmed by the rather low values of RSD (2.82%, n = 11; 2.44%, n = 9) obtained for assays of a blank solution and for 0.02 ng mL−1 RIgG solution, respectively.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Analytica Chimica Acta - Volume 538, Issues 1–2, 4 May 2005, Pages 159-164
نویسندگان
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