Quantum dot induced acute changes in lung mechanics are mouse strain dependent

A Review of in vivo Toxicity of Quantum Dots in Animal Models

Tremendous research efforts have been devoted to nanoparticles for applications in optoelectronics and biomedicine. Over the past decade, quantum dots (QDs) have become one of the fastest growing areas of research in nanotechnology because of outstanding photophysical properties, including narrow and symmetrical emission spectrum, broad fluorescence excitation spectrum, the tenability of the emission wavelength with the particle size and composition, anti-photobleaching ability and stable fluorescence. These characteristics are suitable for optical imaging, drug delivery and other biomedical applications. Research on QDs toxicology has demonstrated QDs affect or damage the biological system to some extent, and this situation is generally caused by the metal ions and some special properties in QDs, which hinders the further application of QDs in the biomedical field. The toxicological mechanism mainly stems from the release of heavy metal ions and generation of reactive oxygen species (ROS). At the same time, the contact reaction with QDs also cause disorders in organelles and changes in gene expression profiles. In this review, we try to present an overview of the toxicity and related toxicity mechanisms of QDs in different target organs. It is believed that the evaluation of toxicity and the synthesis of environmentally friendly QDs are the primary issues to be addressed for future widespread applications. However, considering the many different types and potential modifications, this review on the potential toxicity of QDs is still not clearly elucidated, and further research is needed on this meaningful topic.

Recent advances in nanoparticle applications in respiratory disorders: a review

Various nanoparticles are used in the discovery of new nanomedicine to overcome the shortages of conventional drugs. Therefore, this article presents a comprehensive and up-to-date review of the effects of nanoparticle-based drugs in the treatment of respiratory disorders, including both basic and clinical studies. Databases, including PubMed, Web of Knowledge, and Scopus, were searched until the end of August 2022 regarding the effect of nanoparticles on respiratory diseases. As a new tool, nanomedicine offered promising applications for the treatment of pulmonary diseases. The basic composition and intrinsic characteristics of nanomaterials showed their effectiveness in treating pulmonary diseases. The efficiency of different nanomedicines has been demonstrated in experimental animal models of asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis (PF), lung cancer, lung infection, and other lung disorders, confirming their function in the improvement of respiratory disorders. Various types of nanomaterials, such as carbon nanotubes, dendrimers, polymeric nanomaterials, liposomes, quantum dots, and metal and metal oxide nanoparticles, have demonstrated therapeutic effects on respiratory disorders, which may lead to new possible remedies for various respiratory illnesses that could increase drug efficacy and decrease side effects.

An update on the biological effects of quantum dots: From environmental fate to risk assessment based on multiple biological models

Quantum dots (QDs) are zero-dimension nanomaterials with excellent physical and chemical properties, which have been widely used in environmental science and biomedicine. Therefore, QDs are potential to cause toxicity to the environment and enter organisms through migration and bioenrichment effects. This review aims to provide a comprehensive and systematic analysis on the adverse effects of QDs in different organisms based on recently available data. Following PRISMA guidelines, this study searched PubMed database according to the pre-set keywords, and included 206 studies according to the inclusion and elimination criteria. CiteSpace software was firstly used to analyze the keywords of included literatures, search for breaking points of former studies, and summarize the classification, characterization and dosage of QDs. The environment fate of QDs in the ecosystems were then analyzed, followed with comprehensively summarized toxicity outcomes at individual, system, cell, subcellular and molecular levels. After migration and degradation in the environment, aquatic plants, bacteria, fungi as well as invertebrates and vertebrates have been found to be suffered from toxic effects caused by QDs. Aside from systemic effects, toxicity of intrinsic QDs targeting to specific organs, including respiratory system, cardiovascular system, hepatorenal system, nervous system and immune system were confirmed in multiple animal models. Moreover, QDs could be taken up by cells and disturb the organelles, which resulted in cellular inflammation and cell death, including autophagy, apoptosis, necrosis, pyroptosis and ferroptosis. Recently, several innovative technologies, like organoids have been applied in the risk assessment of QDs to promote the surgical interventions of preventing QDs' toxicity. This review not only aimed at updating the research progress on the biological effects of QDs from environmental fate to risk assessment, but also overcame the limitations of available reviews on basic toxicity of nanomaterials by interdisciplinarity and provided new insights for better applications of QDs.

Applications and Immunological Effects of Quantum Dots on Respiratory System

Quantum dots (QDs), are one kind of nanoscale semiconductor crystals with specific electronic and optical properties, offering near-infrared mission and chemically active surfaces. Increasing interest for QDs exists in developing theranostics platforms for bioapplications such as imaging, drug delivery and therapy. Here we summarized QDs' biomedical applications, toxicity, and immunological effects on the respiratory system. Bioapplications of QDs in lung include biomedical imaging, drug delivery, bio-sensing or diagnosis and therapy. Generically, toxic effects of nanoparticles are related to the generation of oxidative stresses with subsequent DNA damage and decreased lung cells viability in vitro and in vivo because of release of toxic metal ions or the features of QDs like its surface charge. Lastly, pulmonary immunological effects of QDs mainly include proinflammatory cytokines release and recruiting innate leukocytes or adaptive T cells.

Research progress in synthesis and biological application of quantum dots

Quantum dots are an excellent choice for biomedical applications due to their special optical properties and quantum confinement effects. This paper reviews the research and application progress of several quantum...

Nanotechnologies for intranasal drug delivery: an update of literature

Scientific research has focused its attention on finding an alternative route to systemic oral and parenteral administration, to overcome their usual drawbacks, such as hepatic first-pass which decreases drug bioavailability after oral administration, off-target effects, low patient compliance and low speed of onset of the pharmacological action in first-aid cases. Innovative drug delivery systems (DDS), mainly based on polymer and lipid biocompatible materials, have given a great prompt in this direction in the last years. The intranasal (IN) route of administration is a valid non-invasive alternative. It is highly suitable for self-administration, the drug quickly reaches the bloodstream, largely avoiding the first pass effect, and can also reach directly the brain bypassing BBB. Association of IN route with DDS can thus become a winning strategy for the controlled delivery of drugs, especially when a very quick effect is desired or needed. This review aims at analyzing the scientific literature regarding IN-DDS and their different ways of administration (systemic, topical, pulmonary, nose-to-brain). In particular, attention was devoted to polymer- and lipid-based micro- and nanocarriers, being the topic of most published articles in the last decade, but the whole plethora of colloidal DDS investigated in recent years for IN administration was presented.

Toxicity of quantum dots on target organs and immune system

Quantum dots (QDs), due to their superior luminous properties, have been proven to be a very promising biological probe, which can be used as a candidate material for clinical applications. The toxicity of QDs in the environment and biological systems has caused widespread concern in the nanosphere, but their immune toxicity and their impact on the immune system are still relatively unknown. At present, the research on the toxicity of QDs is mainly focused on in vitro models, but few have systematically evaluated their adverse effects on target organs. Animal studies have shown that QDs can be accumulated in various organs due to their main exposure routes, thereby posing a potential threat to major organs. This review briefly describes general characteristics and the wide medical applications of QDs and focuses on the adverse effects of QDs on major target organs, such as liver, lung, kidney, brain, and spleen, after acute and chronic exposure. QDs mainly cause changes in the corresponding indicators of target organs, such as oxidative damage, and in severe cases cause hyperemia, tissue necrosis, and even death. In addition to causing direct damage to target organs, QDs can also cause a large number of immune cells to accumulate and cause inflammatory reactions when causing damage to other major organs. Whether it is to avoid the risk of people contacting QDs in production and life, or to realize the clinical applications of QDs, is very essential to conduct systematic in vivo toxicity assessment of QDs.

The cytotoxicity of core-shell or non-shell structure quantum dots and reflection on environmental friendly: A review

Quantum dots are widely applicated into bioindustry and research owing to its superior properties such as broad excitation spectra, narrow bandwidth emission spectra and high resistance to photo-bleaching. However, the toxicity of quantum dots should not be underestimated and aroused widespread concern. The surface properties and size of quantum dots are critical relevant properties on toxicity. Then, the core/shell structure becomes one common way to affect the activity of quantum dots such as enhance biocompatibility and stability. Except those toxicity it induced, the problem it brought into the environment such as the degradation of quantum dot similarly becomes a hot issue. This review initially took a brief scan of current research on the cytotoxicity of QDs and the mechanism behind that over the past five years. Mainly discussion concentrated on the diversity of structure on quantum dots whether played a key role on the cytotoxicty of quantum dots. It also discussed the role of different shells with metal or nonmetal cores and the influence on the environment.

Visualizing the Fate of Intra-Articular Injected Mesenchymal Stem Cells In Vivo in the Second Near-Infrared Window for the Effective Treatment of Supraspinatus Tendon Tears

Mesenchymal stem cells (MSCs) are capable of exerting strong therapeutic potential for the treatment of supraspinatus tendon tear. However, MSC therapy remains underutilized and perhaps underrated due to the limited evidence of dynamic visualization of cellular behavior in vivo. Here, second near-infrared fluorescence imaging with biocompatible PbS quantum dots (QDs) provides a cellular migration map and information on the biodistribution and clearance processes of three densities of intra-articularly injected, labeled MSCs to treat supraspinatus tendon tear in mice. Intra-articular injection avoids entrapment of MSCs by filter organs and reduces the QD-induced organ toxicity. Notably, the MSCs share a similar migration direction, but the moderate density group is somewhat more efficient, showing the longest residence time and highest cell retention rate around the footprint during the repair stage. Furthermore, quantitative kinetic investigation demonstrates that labeled MSCs are cleared by feces and urine. Histomorphometric analysis demonstrates that the moderate density group achieves maximum therapeutic effect and labeled MSCs do not induce any injury or inflammation to major organs, which suggests that administration of too many or few MSCs may decrease their effectiveness. Such an imaging approach provides spatiotemporal evidence for response to MSC therapy in vivo, facilitating the optimization of MSC therapy.