Structural parameters of nanoparticles affecting their toxicity for biomedical applications: a review

Abstract

Rapidly growing interest in using nanoparticles (NPs) for biomedical applications has increased concerns about their safety and toxicity. In comparison with bulk materials, NPs are more chemically active and toxic due to the greater surface area and small size. Understanding the NPs’ mechanism of toxicity, together with the factors influencing their behavior in biological environments, can help researchers to design NPs with reduced side effects and improved performance. After overviewing the classification and properties of NPs, this review article discusses their biomedical applications in molecular imaging and cell therapy, gene transfer, tissue engineering, targeted drug delivery, Anti-SARS-CoV-2 vaccines, cancer treatment, wound healing, and anti-bacterial applications. There are different mechanisms of toxicity of NPs, and their toxicity and behaviors depend on various factors, which are elaborated on in this article. More specifically, the mechanism of toxicity and their interactions with living components are discussed by considering the impact of different physiochemical parameters such as size, shape, structure, agglomeration state, surface charge, wettability, dose, and substance type. The toxicity of polymeric, silica-based, carbon-based, and metallic-based NPs (including plasmonic alloy NPs) have been considered separately.

Material and Design Toolkit for Drug Delivery: State of the Art, Trends, and Challenges

“…The smallest particles (smaller than 5 nm) can move from the cytoplasm into the nucleus and damage DNA. 274,275 The surface potential of the carrier is reported as the zeta potential, and its magnitude depends on the particle size. Zeta potentials indicate the stability and bioavailability of nanocarriers in aqueous or biological media.…”

“…Particles with 100–200 nm size exhibit a minimum cellular uptake, whereas particles smaller than 100 nm enter the cells and release their cargo into the cytoplasm. The smallest particles (smaller than 5 nm) can move from the cytoplasm into the nucleus and damage DNA. , …”

Strategies for the eradication of intracellular bacterial pathogens

“…Many factors such as nanoparticle size, shape, agglomeration state, surface functionalization, and exposure duration can influence their toxicity. 129,130 The chitosan-coated nanoparticles have been suggested to be toxic, and their toxicity is associated with the molecular weight (MW) and acetylation degree of surface-coated chitosan. 131,132 Silver nanoparticles have been shown to cause mitochondrial dysfunction and cell death by affecting the metabolic activity and generating ROS, which is mainly due to the unleashed silver ions.…”

Exploring Antibacterial Activity and Bacterial-Mediated Allotropic Transition of Differentially Coated Selenium Nanoparticles

“…Nanoparticles (NPs) are materials with dimensions between 1 and 100 nm for at least one of their cross-sectional diameters . Due to the increased surface-to-volume ratio compared to bulk materials, optical, physical, and chemical properties of NPs can be significantly altered, thereby, enabling unique applications in health and industry. , In this respect, metal NPs have previously been reported to exhibit antimicrobial activity. , Apart from titanium oxide, copper oxide, or zinc oxide, silver NPs (AgNPs) display the most investigated antimicrobial particles and are of growing interest for applications in medicine …”