Pulmonary fate and consequences of transferrin-functionalized gold nanoparticles

Oxidative stress and potential effects of metal nanoparticles: A review of biocompatibility and toxicity concerns

Metal nanoparticles (M-NPs) have garnered significant attention due to their unique properties, driving diverse applications across packaging, biomedicine, electronics, and environmental remediation. However, the potential health risks associated with M-NPs must not be disregarded. M-NPs' ability to accumulate in organs and traverse the blood-brain barrier poses potential health threats to animals, humans, and the environment. The interaction between M-NPs and various cellular components, including DNA, multiple proteins, and mitochondria, triggers the production of reactive oxygen species (ROS), influencing several cellular activities. These interactions have been linked to various effects, such as protein alterations, the buildup of M-NPs in the Golgi apparatus, heightened lysosomal hydrolases, mitochondrial dysfunction, apoptosis, cell membrane impairment, cytoplasmic disruption, and fluctuations in ATP levels. Despite the evident advantages M-NPs offer in diverse applications, gaps in understanding their biocompatibility and toxicity necessitate further research. This review provides an updated assessment of M-NPs' pros and cons across different applications, emphasizing associated hazards and potential toxicity. To ensure the responsible and safe use of M-NPs, comprehensive research is conducted to fully grasp the potential impact of these nanoparticles on both human health and the environment. By delving into their intricate interactions with biological systems, we can navigate the delicate balance between harnessing the benefits of M-NPs and minimizing potential risks. Further exploration will pave the way for informed decision-making, leading to the conscientious development of these nanomaterials and safeguarding the well-being of society and the environment.

Endotracheal nebulization of gold nanoparticles for noninvasive pulmonary drug delivery

Background & aims: Gold nanoparticles (AuNPs) are useful tools for noninvasive drug delivery. AuNP nebulization has shown poor deposition results, and AuNP tracking postadministration has involved methods inapplicable to clinical settings. The authors propose an intratracheal delivery method for minimal AuNP loss and computed tomography scans for noninvasive tracking. Materials & methods: Through high-frequency and directed nebulization postendotracheal intubation, the authors treated rats with AuNPs. Results & conclusion: The study showed a dose-dependent and bilateral distribution of AuNPs causing no short-term distress to the animal or risk of airway inflammation. The study demonstrated that AuNPs do not deposit in abdominal organs and show targeted delivery to human lung fibroblasts, offering a specific and noninvasive strategy for respiratory diseases requiring long-term therapies.

Pharmacokinetics and tumor delivery of nanoparticles

Nanoparticles (NPs) have been widely used in different areas, including consumer products and medicine. In terms of biomedical applications, NPs or NP-based drug formulations have been extensively investigated for cancer diagnostics and therapy in preclinical studies, but the clinical translation rate is low. Therefore, a thorough and comprehensive understanding of the pharmacokinetics of NPs, especially in drug delivery efficiency to the target therapeutic tissue tumor, is important to design more effective nanomedicines and for proper assessment of the safety and risk of NPs. This review article focuses on the pharmacokinetics of both organic and inorganic NPs and their tumor delivery efficiencies, as well as the associated mechanisms involved. We discuss the absorption, distribution, metabolism, and excretion (ADME) processes following different routes of exposure and the mechanisms involved. Many physicochemical properties and experimental factors, including particle type, size, surface charge, zeta potential, surface coating, protein binding, dose, exposure route, species, cancer type, and tumor size can affect NP pharmacokinetics and tumor delivery efficiency. NPs can be absorbed with varying degrees following different exposure routes and mainly accumulate in liver and spleen, but also distribute to other tissues such as heart, lung, kidney and tumor tissues; and subsequently get metabolized and/or excreted mainly through hepatobiliary and renal elimination. Passive and active targeting strategies are the two major mechanisms of tumor delivery, while active targeting tends to have less toxicity and higher delivery efficiency through direct interaction between ligands and receptors. We also discuss challenges and perspectives remaining in the field of pharmacokinetics and tumor delivery efficiency of NPs.

Lessons from the history of inorganic nanoparticles for inhalable diagnostics and therapeutics

The respiratory tract is one of the most accessible ones to exogenous nanoparticles, yet drug delivery by their means to it is made extraordinarily challenging because of the plexus of aerodynamic, hemodynamic and biomolecular factors at cellular and extracellular levels that synergistically define the safety and efficacy of this process. Here, the use of inorganic nanoparticles (INPs) for inhalable diagnostics and therapies of the lung is viewed through the prism of the history of studies on the interaction of INPs with the lower respiratory tract. The most conceptually and methodologically innovative and illuminative studies are referred to in the chronological order, as they were reported in the literature, and the trends in the progress of understanding this interaction of immense therapeutic and toxicological significance are being deduced from it. The most outstanding actual trends delineated include the diminishment of toxicity via surface functionalization, cell targeting, tagging and tracking via controlled binding and uptake, hybrid INP treatments, magnetic guidance, combined drug and gene delivery, use as adjuvants in inhalable vaccines, and other. Many of the understudied research directions, which have been accomplished by the nanostructured organic polymers in the pulmonary niche, are discussed. The progress in the use of INPs as inhalable diagnostics or therapeutics has been hampered by their well-recognized inflammatory potential and toxicity in the respiratory tract. However, the annual numbers of methodologically innovative studies have been on the rise throughout the past two decades, suggesting that this is a prolific direction of research, its comparatively poor commercial takings notwithstanding. Still, the lack of consensus on the effects of many INP compositions at low but therapeutically effective doses, the plethora of contradictory reports on ostensibly identical chemical compositions and NP properties, and the many cases of antagonism in combinatorial NP treatments imply that the rational design of inhalable medical devices based on INPs must rely on qualitative principles for the most part and embrace a partially stochastic approach as well. At the same time, the fact that the most studied INPs for pulmonary applications have been those with some of the thickest records of pulmonary toxicity, e.g., carbon, silver, gold, silica and iron oxide, is a silent call for the expansion of the search for new inorganic compositions for use in inhalable therapies to new territories.

A Non-Invasive Method for Monitoring Osteogenesis and Osseointegration Using Near-Infrared Fluorescent Imaging: A Model of Maxilla Implantation in Rats

Currently, computed tomography and conventional X-ray radiography usually generate a micro-artifact around metal implants. This metal artifact frequently causes false positive or negative diagnoses of bone maturation or pathological peri-implantitis around implants. In an attempt to repair the artifacts, a highly specific nanoprobe, an osteogenic biomarker, and nano-Au-Pamidronate were designed to monitor the osteogenesis. In total, 12 Sprague Dawley rats were included in the study and could be chategorized in 3 groups: 4 rats in the X-ray and CT group, 4 rats in the NIRF group, and 4 rats in the sham group. A titanium alloy screw was implanted in the anterior hard palate. The X-ray, CT, and NIRF images were taken 28 days after implantation. The X-ray showed that the tissue surrounded the implant tightly; however, a gap of metal artifacts was noted around the interface between dental implants and palatal bone. Compared to the CT image, a fluorescence image was noted around the implant site in the NIRF group. Furthermore, the histological implant-bone tissue also exhibited a significant NIRF signal. In conclusion, this novel NIRF molecular imaging system precisely identifies the image loss caused by metal artifacts and can be applied to monitoring bone maturation around orthopedic implants. In addition, by observing the new bone formation, a new principle and timetable for an implant osseointegrated with bone can be established and a new type of implant fixture or surface treatment can be evaluated using this system.