%0 Journal Article
%T The Activity of [60]Fullerene Derivatives Bearing Amine and Carboxylic Solubilizing Groups against Escherichia coli: A Comparative Study
%A Dmitry G. Deryabin
%A Olga K. Davydova
%A Zulfiya ZH. Yankina
%A Alexey S. Vasilchenko
%A Sergei A. Miroshnikov
%A Alexey B. Kornev
%A Anastasiya V. Ivanchikhina
%A Pavel A. Troshin
%J Journal of Nanomaterials
%D 2014
%I Hindawi Publishing Corporation
%R 10.1155/2014/907435
%X We report a comparative investigation of the antibacterial activity of two water-soluble fullerene derivatives bearing protonated amine (AF) and deprotonated carboxylic (CF) groups appended to the fullerene cage via organic linkers. The negatively charged fullerene derivative CF showed no tendency to bind to the bacterial cells and, consequently, no significant antibacterial activity. In contrast, the compound AF loaded with cationic groups showed strong and partially irreversible binding to the negatively charged Escherichia coli K12 TG1 cells and to human erythrocytes, also possessing negative zeta potential. Adsorption of AF on the bacterial surface was visualized by atomic force microscopy revealing the formation of specific clusters (AF aggregates) surrounding the bacterial cell. Incubation of E. coli K12 TG1 with AF led to a dose-dependent bactericidal effect with £¿¦ÌM. The presence of human erythrocytes in the test medium decreased the AF antibacterial activity. Thus we reveal that the water-soluble cationic fullerene derivative AF possesses promising antibacterial activity, which might be utilized in the development of novel types of chemical disinfectants. 1. Introduction Investigation of carbon-based nanomaterials (CBN) has made a great impact on the research in the fields of physics, material chemistry and technology, and also life sciences. Water-soluble forms of carbon have been studied intensively worldwide during recent decades. We would like to refer to [1], dedicated to the studies of biological activity of CBN [1]. Toxicity and biocompatibility of CBN were two major points addressed in this journal. Several review papers discussing the biological activities of CBN appeared later [2¨C4]. Fullerenes, the spherical carbon cages, and their functional derivatives attracted particular attention due to their unusual molecular structures and properties. Recent publications proved lower toxicity of fullerenes compared to other types of CBN, especially carbon nanotubes [5, 6]. It is known that pristine fullerenes such as C60 and C70 are very hydrophobic and possess virtually zero solubility in water. Classical fullerene derivatives bearing one organic addend appended to the fullerene cage typically have a strong tendency to aggregate in aqueous solutions [7]. Such aggregation lowers their activity significantly and hinders their practical applications. The problem can be solved by using chemically functionalized fullerene derivatives bearing a sufficient number of hydrophilic (or, even better, ionic) functional groups that significantly improve
%U http://www.hindawi.com/journals/jnm/2014/907435/