Electrochemical detection of interactions between DNA and various ligands
type: CreativeWork
description: Antibodies specific for DNA, with varying degrees of sequence specificity, are common in many autoimmune diseases including systemic lupus erythematosus. The presence of anti-DNA antibodies is a useful determinant in arriving at a prognosis in these conditions. Given the prevalence of these diseases in both the developing and developed world and the difficulty that often accompanies diagnosis of autoimmune diseases, it is desirable to have sensitive, rapid, and inexpensive diagnostic tools for these diseases. Because of the great sensitivity of electrochemical techniques and their potential utility in characterizing interactions between macromolecules, electrochemistry has great potential as a diagnostic tool for any disease involving antibodies. Anti-DNA antibodies are present in many autoimmune diseases, notably systemic lupus erythematosus. Since DNA is a stable and well-characterized antigen, an electrochemical-based assay is particularly useful for diagnosis of these diseases. The impedance of a gold surface was measured in the presence and absence of single- and double-stranded DNA monolayers. The DNA monolayer was diluted with butanethiol in order to provide a surface with more accessible binding sites than an undiluted monolayer. The change in impedance of the DNA monolayer following exposure to various small molecules and macromolecules was assessed. The molecules used included polyamines that induce conformational changes in DNA, proteins which bind DNA specifically, proteins which bind DNA non-specifically, and proteins which do not bind DNA. The presence of a DNA monolayer, whether single- or double-stranded, increased the impedance of the gold surface and dilution of the monolayers by butanethiol decreased the impedance, as expected. When exposed to polyamines, the impedance of the DNA monolayer decreased further. This could be due to lowered charge repulsion, to DNA condensation, or to a combination of both. When methylated bovine serum albumin was exp…
abstract: Antibodies specific for DNA, with varying degrees of sequence specificity, are common in many autoimmune diseases including systemic lupus erythematosus. The presence of anti-DNA antibodies is a useful determinant in arriving at a prognosis in these conditions. Given the prevalence of these diseases in both the developing and developed world and the difficulty that often accompanies diagnosis of autoimmune diseases, it is desirable to have sensitive, rapid, and inexpensive diagnostic tools for these diseases. Because of the great sensitivity of electrochemical techniques and their potential utility in characterizing interactions between macromolecules, electrochemistry has great potential as a diagnostic tool for any disease involving antibodies. Anti-DNA antibodies are present in many autoimmune diseases, notably systemic lupus erythematosus. Since DNA is a stable and well-characterized antigen, an electrochemical-based assay is particularly useful for diagnosis of these diseases. The impedance of a gold surface was measured in the presence and absence of single- and double-stranded DNA monolayers. The DNA monolayer was diluted with butanethiol in order to provide a surface with more accessible binding sites than an undiluted monolayer. The change in impedance of the DNA monolayer following exposure to various small molecules and macromolecules was assessed. The molecules used included polyamines that induce conformational changes in DNA, proteins which bind DNA specifically, proteins which bind DNA non-specifically, and proteins which do not bind DNA. The presence of a DNA monolayer, whether single- or double-stranded, increased the impedance of the gold surface and dilution of the monolayers by butanethiol decreased the impedance, as expected. When exposed to polyamines, the impedance of the DNA monolayer decreased further. This could be due to lowered charge repulsion, to DNA condensation, or to a combination of both. When methylated bovine serum albumin was exp…
author: Muresan, Alina
language: en_US
keywords: DNA-binding drugs, DNA-binding proteins, electrochemistry
date published: 2007-12-04
date modified: 2026-07-24T04:27:16Z
provider: University of Saskatchewan
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Saskatchewan

PropertyValue
property ID: Handle
value: https://hdl.handle.net/10388/etd-12032007-212936