Comparing Methods for Detecting and Characterizing Metal Oxide Nanoparticles in Unmodified Commercial Sunscreens

Abstract

As with all surgical procedures, implantation comes with the added risk of infection. The goal of this in vitro study was to explore the use of superparamagnetic iron oxide nanoparticles (SPION) as a multifunctional platform to prevent biofilm formation. Results showed for the first time decreased Staphylococcus epidermidis numbers when exposed to 100 μg/ml of SPION for 12 hours and this trend continued for up to 48 hours. Prevention of colony assembly, a prerequisite to biofilm formation, was also observed at lower SPION dosages of 10 μg/ml after 12 hours. Coupled with previous studies demonstrating enhanced bone cell functions in the presence of the same concentration of SPION, the present results provided much promise for the use of SPION for numerous anti-infection orthopedic applications.

Effects of iron oxide nanoparticles on biological responses and MR imaging properties in human mammary healthy and breast cancer epithelial cells

“…Because of the tightly controlled focal planes of the confocal microscope, a three dimensional profile is constructed of the nanoparticle distribution. 23 This allows for determining if NPs are indeed localized within the cell as opposed to associated with the cell surface. Figure 4(a,b) show the overlay of bright field, nuclear staining, and NP reflectance (top) and the corresponding 3D reconstruction from the Z series (bottom).…”

Synthesis, characterization and antibacterial activity of superparamagnetic nanoparticles modified with glycol chitosan

“…A plausible mechanism of the antibacterial action of the bare IONPs is that metal oxide (Fe 3 O 4 ) may generate reactive oxygen species via the Fenton reaction, leading to lipid peroxidation, DNA damage and protein oxidation [4]. Additionally, owing to the positively charged surface, metal oxides may bind to negatively charged cell membranes through electrostatic interaction, thereby disrupting bacterial functions [2]. This phenomenon is proven by the fact that Gram-negative bacteria have a more negative charge on the surface than the Gram-positive ones [29].…”

“…Given the increased bacterial resistance to conventional antibiotics, the development of alternative antibiotics has received considerable attention in the past decade [1,2]. Also, infections resulting from the formation of bacterial slime or biofilms at the surface of an array of implantable devices present a major medical problem as a biofilm can promote bacterial resistance by restraining antibiotic treatment and host immune response [2].…”

“…Also, infections resulting from the formation of bacterial slime or biofilms at the surface of an array of implantable devices present a major medical problem as a biofilm can promote bacterial resistance by restraining antibiotic treatment and host immune response [2]. The formation of microbial biofilms is mostly associated with the bacterial ability to adhere onto material surfaces through nonspecific interactions such as electrostatic, hydrophobic and van der Waals interactions; this ability is reversible at first and later becomes irreversible during the infection process [3].…”

“…Recent advancements in the field of nanotechnology have provided attractive solutions for synthesizing alternative antimicrobial agents and reducing biofilm formation [2,4]. For instance, silver nanoparticles can reduce infections on implanted devices, preserve food and develop antimicrobial finished textile fabrics [5][6][7].…”