Nanotoxicity of polyelectrolyte-functionalized titania nanoparticles towards microalgae and yeast: role of the particle concentration, size and surface charge

Abstract

We explore the effects of the particle size and the surface charge of polyelectrolyte-coated titania nanoparticles on their toxicity towards green microalgae and yeast cells in UV/vis light.

Self-grafting copper oxide nanoparticles show a strong enhancement of their anti-algal and anti-yeast action

“…One mechanism is based on the photoactive nature of these nanoparticles which in the presence of oxygen from air and visible or UV light, form ROS which are free radicals and lead to peroxidation of lipids from the bacterial cell membrane. 2,23,65,66 The cell wall of the Fig. 4 The antialgal activity of bare, GLYMO or 4-HPBA-GLYMO-functionalized CuONPs at various concentrations (0, 5, 10, 15, 20 and 25 mg mL À1 ) on C. reinhardtii.…”

“…22 Al-Awady et al studied the antimicrobial effect of titania nanoparticles (TiO 2 NPs) of various particle sizes towards C. reinhardtii and S. cerevisiae upon illumination with UV and visible light for a range of nanoparticle concentrations and incubation times. 23 They also conrmed that bare TiO 2 NPs affect the C. reinhardtii cells viability at much lower particle concentrations than for S. cerevisiae. The antimicrobial action of TiO 2 NPs increased slightly upon illumination with UV light compared with that in dark conditions due to the additional oxidative stress of the produced reactive oxygen species (ROS).…”

Investigation of Anti-MRSA and Anticancer Activity of Eco-Friendly Synthesized Silver Nanoparticles from Palm Dates Extract

“…On the other hand, M. morganii and S. aureus had slightly shown antibacterial activity and they needed as greater silver NPs concentration as 200 µg/mL to improve the activity. The reason behind antimicrobial action of silver NPs is related to some potential mechanisms such as direct internalization of NPs which leads to cell death, generation of reactive oxygen species (ROS) such as hydrogen peroxide, hydroxyl, and superoxide radicals, electrostatic interaction between the surface charge of nanomaterial, and the opposed charge on the outer cell wall membrane of microorganism [4]. Silver NPs could also release cationic silver ions which either bound with proteins of outer membrane of bacteria causing denaturation or penetrate through cell wall into cytoplasm making cell damage and death [35].…”

“…The chemical composition on the particle surface, particle size, and surface charge has significant effects on the behavior of nanoparticles (NPs) [4][5][6][7]. Several chemical and physical methods were utilized to synthesize metal NPs, such as chemical reduction [8], electrochemical reduction [9], heat evaporation [10] and microwave irradiation [11].…”

Boosting Antimicrobial Activity of Imipenem in Combination with Silver Nanoparticles towards S. fonticola and Pantoea sp.

“…Nano silvers, which are zero valent, can be a valued alternative to silver ions [3]. Nanoparticles (NPs) are clusters of atoms, with sizes ranging from 1 to 100 nm, whereas a "nano" is used to designate one billionth of a meter [4]. Due to the fact that their small particle size and high surface area, silver NPs have unique physical and chemical properties which are different from those of metallic silver.…”