RESUMO
The study of the electrical properties of DNA has aroused increasing interest since the last decade. So far, controversial arguments have been put forward to explain the electrical charge transport through DNA. Our experiments on DNA bundles manipulated with silicon-based actuated tweezers demonstrate undoubtedly that humidity is the main factor affecting the electrical conduction in DNA. We explain the quasi-Ohmic behavior of DNA and the exponential dependence of its conductivity with relative humidity from the adsorption of water on the DNA backbone. We propose a quantitative model that is consistent with previous studies on DNA and other materials, like porous silicon, subjected to different humidity conditions.
Assuntos
DNA/química , Micromanipulação/instrumentação , Modelos Químicos , Modelos Moleculares , Nanotecnologia/instrumentação , Silício , Simulação por Computador , Transporte de Elétrons , Desenho de Equipamento , Análise de Falha de Equipamento , Umidade , Micromanipulação/métodos , Nanotecnologia/métodos , Eletricidade EstáticaRESUMO
An electrochemical determination of the O2- concentration from KO2 in DMSO solution using steady state microelectrode voltammetry shows that the KO2/DMSO method with the combined use of a crown compound or sonication is a reliable and simple technique for introduction of O2- to the biomimitic reaction system.