Assessment of CdS quantum dots effect on UV damage to DNA using a DNA/quantum dots structured electrochemical biosensor and DNA biosensing in solution

作者：Svitkova Veronika; Blaskovicova Jana; Tekelova Monika; Kallai Brigitta Margit; Ignat Teodora; Horackova Veronika; Skladal Petr; Kopel Pavel; Adam Vojtech; Farkasova Dana; Labuda Jan^*

来源：Sensors and Actuators B: Chemical , 2017, 243: 435-444.

DOI：10.1016/j.snb.2016.11.160

• Nanoparticles toxicity
• Quantum dots
• UV-C radiation
• DNA damage
• Biosensor
• Biosensing

Oxidation stress induced by nanoparticles is considered to be the main mechanism of their toxicity. An evaluation of oxidative damage to DNA, one of the mostly endangered molecules, belongs to general approaches used in nanomaterials cytotoxicology. However, for spherical, biochemical and other reasons, they should be differences in nanoparticles behaviour using tests based on cells and pure nucleic acid substances. The goal of the work is to detect structural damage to isolated salmon sperm double stranded DNA at its exposure to UV-C radiation (254 nm) in the presence of thiol-capped CdS quantum dots of various size and fluorescence intensity. An electrochemical DNA-based biosensor composed of a glassy carbon electrode with a layered structure of chemical modifiers dsDNA and CdS (Ps was prepared and used for the voltammetric and impedimetric evaluation of a DNA portion survived after the irradiation. The cyclic voltammetric response of the redox indicator system hexacyanoferrate(III/II) and square wave voltammetric response of the guanine and adenine moieties were measured as analytical signals. The results were verified by experiments with irradiation of DNA in the solution phase followed by voltammetric measurement of immobilized survived portion of DNA (biosensing) and by conventional agarose gel electrophoresis. Experiments showed significant effect of the fluorescent active quantum dots on the degree of DNA degradation.

• 出版日期2017-5