Hemolysis of Human Erythrocytes by Argovit™ AgNPs from Healthy and Diabetic Donors: An In Vitro Study

The use of nanomaterials is becoming increasingly widespread, leading to substantial research focused on nanomedicine. Nevertheless, the lack of complete toxicity profiles limits nanomaterials' uses, despite their remarkable diagnostic and therapeutic results on in vitro and in vivo models. Silver nanoparticles (AgNPs), particularly Argovit™, have shown microbicidal, virucidal, and antitumoral effects. Among the first-line toxicity tests is the hemolysis assay. Here, the hemolytic effect of Argovit™ AgNPs on erythrocytes from one healthy donor (HDE) and one diabetic donor (DDE) is evaluated by the hemolysis assay against AgNO3. The results showed that Argovit™, in concentrations ≤24 µg/mL of metallic silver, did not show a hemolytic effect on the HDE or DDE. On the contrary, AgNO3 at the same concentration of silver ions produces more than 10% hemolysis in both the erythrocyte types. In all the experimental conditions assessed, the DDE was shown to be more prone to hemolysis than the HDE elicited by Ag+ ions or AgNPs, but much more evident with Ag+ ions. The results show that Argovit™ is the least hemolytic compared with the other twenty-two AgNP formulations previously reported, probably due to the polymer mass used to stabilize the Argovit™ formulation. The results obtained provide relevant information that contributes to obtaining a comprehensive toxicological profile to design safe and effective AgNP formulations.

Functionalized-AgNPs for Long-Term Stability and Its Applicability in the Detection of Manganese Ions

In this study, silver nanoparticles (AgNPs) were functionalized by various molecules, including sodium borohydride (NaBH4), polyhexamethylene biguanide hydrochloride (PHMB), and Tween 80 to investigate the long-term stabilization of AgNPs in an aqueous dispersion. PHMB-functionalized silver nanoparticles (AgNPs/PHMB) exhibited better stability than others and could be stored at ambient temperature for at least 180 days. In addition to creating stabilization based on the electrostatic repulsion, the use of PHMB helped to increase the degree of stability of the colloidal AgNPs for a long time owing to strong interactions between Ag atoms on AgNPs with nitrogen (N) positions in PHMB molecules. The formed bond led to improving maintenance ability of the electrostatic repulsion layer among independent nanoparticles. The applicability of the as-prepared AgNPs/PHMB was also examined for Mn2+ detection via a colorimetric approach. The calibration curve was found to be linear over the range of 0–100 mM with a correlation coefficient of 0.97. The amine groups of PHMB brought out a cooperative effect to form of ion-templated chelation with Mn2+, which caused the aggregation of AgNPs/PHMB. This suggested that the AgNPs/PHMB could be used as a potential probe in the detection of Mn2+ ions. More importantly, the long-term stability of AgNPs/PHMB paved a great promising path to provide many further solutions for the producer in practical applications.

The evolving landscape of drug products containing nanomaterials in the United States

The Center for Drug Evaluation and Research (CDER) within the US Food and Drug Administration (FDA) is tracking the use of nanotechnology in drug products by building and interrogating a technical profile of products containing nanomaterials submitted to CDER. In this Analysis, data from more than 350 products show an increase in the submissions of drug products containing nanomaterials over the last two decades. Of these, 65% are investigational new drugs, 17% are new drug applications and 18% are abbreviated new drug applications, with the largest class of products being liposomal formulations intended for cancer treatments. Approximately 80% of products have average particle sizes of 300 nm or lower. This analysis identifies several trends in the development of drug products containing nanomaterials, including the relative rate of approvals of these products, and provides a comprehensive overview on the landscape of nanotechnology application in medicine.

Silver Nanoparticles: Synthesis, Characterization, Properties, Applications, and Therapeutic Approaches

Recent advances in nanoscience and nanotechnology radically changed the way we diagnose, treat, and prevent various diseases in all aspects of human life. Silver nanoparticles (AgNPs) are one of the most vital and fascinating nanomaterials among several metallic nanoparticles that are involved in biomedical applications. AgNPs play an important role in nanoscience and nanotechnology, particularly in nanomedicine. Although several noble metals have been used for various purposes, AgNPs have been focused on potential applications in cancer diagnosis and therapy. In this review, we discuss the synthesis of AgNPs using physical, chemical, and biological methods. We also discuss the properties of AgNPs and methods for their characterization. More importantly, we extensively discuss the multifunctional bio-applications of AgNPs; for example, as antibacterial, antifungal, antiviral, anti-inflammatory, anti-angiogenic, and anti-cancer agents, and the mechanism of the anti-cancer activity of AgNPs. In addition, we discuss therapeutic approaches and challenges for cancer therapy using AgNPs. Finally, we conclude by discussing the future perspective of AgNPs.

Detection of Gold Nanoparticles in Rat Organs by Transmission Electron Microscopy

The effects of water-dispersed gold nanoparticles (8.0±0.9 nm in diameter) on the rat small intestinal mucosa and Peyer plaques, liver, and spleen were studied by electron microscopy. Water-dispersed gold nanoparticles injected into isolated intestinal loop not only accumulated in the small intestinal mucosa and Peyer plaques, but also penetrated into other organs, e.g. liver and spleen. Ultrastructural changes in the cells (hyperplasia of endoplasmic reticulum) were detected in the studied organs.

Characterization of engineered TiO₂ nanomaterials in a life cycle and risk assessments perspective

For the last 10 years, engineered nanomaterials (ENMs) have raised interest to industrials due to their properties. They are present in a large variety of products from cosmetics to building materials through food additives, and their value on the market was estimated to reach $3 trillion in 2014 (Technology Strategy Board 2009). TiO2 NMs represent the second most important part of ENMs production worldwide (550-5500 t/year). However, a gap of knowledge remains regarding the fate and the effects of these, and consequently, impact and risk assessments are challenging. This is due to difficulties in not only characterizing NMs but also in selecting the NM properties which could contribute most to ecotoxicity and human toxicity. Characterizing NMs should thus rely on various analytical techniques in order to evaluate several properties and to crosscheck the results. The aims of this review are to understand the fate and effects of TiO2 NMs in water, sediment, and soil and to determine which of their properties need to be characterized, to assess the analytical techniques available for their characterization, and to discuss the integration of specific properties in the Life Cycle Assessment and Risk Assessment calculations. This study underlines the need to take into account nano-specific properties in the modeling of their fate and effects. Among them, crystallinity, size, aggregation state, surface area, and particle number are most significant. This highlights the need for adapting ecotoxicological studies to NP-specific properties via new methods of measurement and new metrics for ecotoxicity thresholds.

Techniques for physicochemical characterization of nanomaterials

Advances in nanotechnology have opened up a new era of diagnosis, prevention and treatment of diseases and traumatic injuries. Nanomaterials, including those with potential for clinical applications, possess novel physicochemical properties that have an impact on their physiological interactions, from the molecular level to the systemic level. There is a lack of standardized methodologies or regulatory protocols for detection or characterization of nanomaterials. This review summarizes the techniques that are commonly used to study the size, shape, surface properties, composition, purity and stability of nanomaterials, along with their advantages and disadvantages. At present there are no FDA guidelines that have been developed specifically for nanomaterial based formulations for diagnostic or therapeutic use. There is an urgent need for standardized protocols and procedures for the characterization of nanoparticles, especially those that are intended for use as theranostics.