Bactericidal Activity of Multilayered Hybrid Structures Comprising Titania Nanoparticles and CdSe Quantum Dots under Visible Light

Abstract

Titania nanoparticle/CdSe quantum dot hybrid structures are a promising bactericidal coating that exhibits a pronounced effect against light-sensitive bacteria. Here, we report the results of a comprehensive study of the photophysical properties and bactericidal functionality of these hybrid structures on various bacterial strains. We found that our structures provide the efficient generation of superoxide anions under the action of visible light due to electron transfer from QDs to titania nanoparticles with ~60% efficiency. We also tested the antibacterial activity of hybrid structures on five strains of bacteria. The formed structures combined with visible light irradiation effectively inhibit the growth of Escherichia coli, Bacillus subtilis, and Mycobacterium smegmatis bacteria, the last of which is a photosensitive causative agent model of tuberculosis.

Sulfide-Capped InP/ZnS Quantum Dot Nanoassemblies for a Photoactive Antibacterial Surface

“…In previous studies, the CdSe QD-coated surface demonstrated approximately 80% antibacterial activity against only nonpathogenic Mycobacterium smegmatis bacterial strains. 28 Another report highlighted nearly 99.9% antibacterial activity for the CdTe QD-coated surface under dark conditions, against only the E. coli strain. 27 In this study, we observed over 80% antibacterial activity against both E. coli and S. aureus bacteria.…”

“…Moreover, the surface functional groups of QDs play a significant role in the efficiency of ROS generation. The enhanced charge carrier extraction and faster transfer of photogenerated electrons are the consequences of surface functioning. − Cadmium-based QDs have shown significant antibacterial activity via ROS generation under illumination. ,− However, the release of cadmium ions into the cells and tissues is a major concern. Alternatively, cadmium-free QDs such as AgBiS 2 , CuInS/ZnS, InP, ,− and ZnO QDs have shown antibacterial activity.…”

Light Absorption Enhancement and Laser-Induced Damage Ability Improvement of Aluminum Alloy 6061 with Non-Porous Alumina/CdSe@Al2O3/SiO2 Functional Gradient Films

“…Semiconductor nanocrystals (SNCs) such as cadmium selenide (CdSe) quantum dots offer wide applications in the fields of photovoltaics, solar energy harvesting, nanophotonics, imaging, sensing and other fields [ 20 , 21 , 22 , 23 , 24 , 25 ]. Since incident radiation causes excitation of free electrons, metal nanoparticles (MNPs) can generate intense electric fields in their vicinity [ 26 ].…”

Генерация активных форм кислорода нанокомпозитами AgInS-=SUB=-2-=/SUB=-/TiO-=SUB=-2-=/SUB=- под действием излучения УФ и видимого диапазонов

“…Актуальной задачей является расширение спектрального диапазона активности TiO 2 в видимую область спектра [10]. Одним из подходов для ее решения является формирование гибридных структур на основе TiO 2 и полупроводниковых квантовых точек (КТ) [11,12]. За счёт эффективного фотоиндуцированного переноса электрона из зоны проводимости КТ в зону проводимости диоксида титана такие структуры будут способны генерировать АФК под действием излучения видимого диапазона [13].…”