Nanotechnology, nanotoxicology, and neuroscience

Nano-Osmolyte Conjugation: Tailoring the Osmolyte-Protein Interactions at the Nanoscale

Osmolytes are small organic compounds accumulated at higher concentrations in the cell under various stress conditions like high temperature, high salt, high pressure, etc. Osmolytes mainly include four major classes of compounds including sugars, polyols, methylamines, and amino acids and their derivatives. In addition to their ability to maintain protein stability and folding, these osmolytes, also termed as chemical chaperones, can prevent protein misfolding and aggregation. Although being efficient protein folders and stabilizers, these osmolytes exhibit certain unavoidable limitations such as nearly molar concentrations of osmolytes being required for their effect, which is quite difficult to achieve inside a cell or in the extracellular matrix due to nonspecificity and limited permeability of the blood-brain barrier system and reduced bioavailability. These limitations can be overcome to a certain extent by using smart delivery platforms for the targeted delivery of osmolytes to the site of action. In this context, osmolyte-functionalized nanoparticles, termed nano-osmolytes, enhance the protein stabilization and chaperone efficiency of osmolytes up to 105 times in certain cases. For example, sugars, polyols, and amino acid functionalized based nano-osmolytes have shown tremendous potential in preventing protein aggregation. The enhanced potential of nano-osmolytes can be attributed to their high specificity at low concentrations, high tunability, amphiphilicity, multivalent complex formation, and efficient drug delivery system. Keeping in view the promising potential of nano-osmolytes conjugation in tailoring the osmolyte-protein interactions, as compared to their molecular forms, the present review summarizes the recent advancements of the nano-osmolytes that enhance the protein stability/folding efficiency and ability to act as artificial chaperones with increased potential to prevent protein misfolding disorders. Some of the potential nano-osmolyte aggregation inhibitors have been highlighted for large-scale screening with future applications in aggregation disorders. The synthesis of nano-osmolytes by numerous approaches and future perspectives are also highlighted.

Recent advances in nanomaterials for neural applications: opportunities and challenges

Nanomedicines are promising for delivering drugs to the central nervous system, though their precision is still being improved. Fortifying nanoparticles with vital molecules can interact with the blood-brain barrier, enabling access to brain tissue. This study summarizes recent advances in nanomedicine to treat neurological complications. The integration of nanotechnology into cell biology aids in the study of brain cells' interactions. Magnetic microhydrogels have exhibited superior neuron activation compared with superparamagnetic iron oxide nanoparticles and hold promise for neuropsychiatric disorders. Nanomaterials have shown notable results, such as tackling neurodegenerative diseases by hindering harmful protein buildup and regulating cellular processes. However, further studies of the safety and effectiveness of nanoparticles in managing neurological diseases and disorders are still required.

Intranasal delivery of stem cells labeled by nanoparticles in neurodegenerative disorders: Challenges and opportunities

Neurodegenerative disorders occur through progressive loss of function or structure of neurons, with loss of sensation and cognition values. The lack of successful therapeutic approaches to solve neurologic disorders causes physical disability and paralysis and has a significant socioeconomic impact on patients. In recent years, nanocarriers and stem cells have attracted tremendous attention as a reliable approach to treating neurodegenerative disorders. In this regard, nanoparticle-based labeling combined with imaging technologies has enabled researchers to survey transplanted stem cells and fully understand their fate by monitoring their survival, migration, and differentiation. For the practical implementation of stem cell therapies in the clinical setting, it is necessary to accurately label and follow stem cells after administration. Several approaches to labeling and tracking stem cells using nanotechnology have been proposed as potential treatment strategies for neurological diseases. Considering the limitations of intravenous or direct stem cell administration, intranasal delivery of nanoparticle-labeled stem cells in neurological disorders is a new method of delivering stem cells to the central nervous system (CNS). This review describes the challenges and limitations of stem cell-based nanotechnology methods for labeling/tracking, intranasal delivery of cells, and cell fate regulation as theragnostic labeling. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Neurological Disease.

Electroosmotically actuated peristaltic-ciliary flow of propylene glycol + water conveying titania nanoparticles

The main focus of this article is to mathematically formulate the microfluidics-based mechanical system for nanofluids. A 50:50 mixture of propylene glycol (PG) and water is used as a heat transfer fluid because of its tremendous anti-freezing properties, and nontoxicity and it is safe to be utilized at the domestic level. Titanium dioxide (titania) nanoparticles are suspended in the working fluid to enhance its heat transfer ability. The fluid flow is induced by electroosmosis in a microtube, which is further assisted by cilia beating. The impacts of Joule heating and non-linear thermal radiation are also considered. The simplification of the dimensionless system is done under lubrication theory and the Debye-Hückel linearization principle. The nonlinear system of equations is executed for a numerical solution by adopting the symbolic mathematical software Maple 17 using the command "dsolve" along with the additional command "numeric" to get the numerical solution. This command utilizes a low-ordered method along with accuracy-enhancing schemes such as the deferred correction technique and Richardson extrapolation to get a numerical answer of desired accuracy, where we can choose the accuracy level and mesh points according to our requirements. The detailed analysis of results obtained from the numerical treatment of the considered problem indicates that the efficiency of the PG + water enhances due to the suspension of the nanoparticles and heat is rapidly removed from the system. Further, the velocity of the fluid is augmented by decreasing the thickness of the electric double layer and raising the strength of the electric field in the forwarding direction.

Magnetic Nanostructures and Stem Cells for Regenerative Medicine, Application in Liver Diseases

The term "liver disease" refers to any hepatic condition that leads to tissue damage or altered hepatic function and can be induced by virus infections, autoimmunity, inherited genetic mutations, high consumption of alcohol or drugs, fat accumulation, and cancer. Some types of liver diseases are becoming more frequent worldwide. This can be related to increasing rates of obesity in developed countries, diet changes, higher alcohol intake, and even the coronavirus disease 2019 (COVID-19) pandemic was associated with increased liver disease-related deaths. Although the liver can regenerate, in cases of chronic damage or extensive fibrosis, the recovery of tissue mass is impossible, and a liver transplant is indicated. Because of reduced organ availability, it is necessary to search for alternative bioengineered solutions aiming for a cure or increased life expectancy while a transplant is not possible. Therefore, several groups were studying the possibility of stem cells transplantation as a therapeutic alternative since it is a promising strategy in regenerative medicine for treating various diseases. At the same time, nanotechnological advances can contribute to specifically targeting transplanted cells to injured sites using magnetic nanoparticles. In this review, we summarize multiple magnetic nanostructure-based strategies that are promising for treating liver diseases.

Titanium-Based Nanoarchitectures for Sonodynamic Therapy-Involved Multimodal Treatments

Sonodynamic therapy (SDT) has considerably revolutionized the healthcare sector as a viable noninvasive therapeutic procedure. It employs a combination of low-intensity ultrasound and chemical entities, known as a sonosensitizer, to produce cytotoxic reactive oxygen species (ROS) for cancer and antimicrobial therapies. With nanotechnology, several unique nanoplatforms are introduced as a sonosensitizers, including, titanium-based nanomaterials, thanks to their high biocompatibility, catalytic efficiency, and customizable physicochemical features. Additionally, developing titanium-based sonosensitizers facilitates the integration of SDT with other treatment modalities (for example, chemotherapy, chemodynamic therapy, photodynamic therapy, photothermal therapy, and immunotherapy), hence increasing overall therapeutic results. This review summarizes the most recent developments in cancer therapy and tissue engineering using titanium nanoplatforms mediated SDT. The synthesis strategies and biosafety aspects of Titanium-based nanoplatforms for SDT are also discussed. Finally, various challenges and prospects for its further development and potential clinical translation are highlighted.

Formulation development of lipid polymer hybrid nanoparticles of doxorubicin and its in-vitro, in-vivo and computational evaluation

The purpose of this study was to assess the parameters of doxorubicin (DOX) loaded lipid polymer hybrid nanoparticles (LPHNs) formulation development, and then the bioavailability of DOX were determined in the rabbit model, in order to evaluate the intrinsic outcome of dosage form improvement after the oral administration. LPHNs were prepared by combine approach, using both magnetic stirring and probe sonication followed by its characterization in terms of size-distribution (Zeta Size), entrapment efficiency (EE), loading capacity, and the kinetics of DOX. LPHNPs were further characterized by using scanning electron microscopy (SEM), powder X-Ray diffractometry (P-XRD), Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), in vitro and in vivo studies. The molecular modeling was determined through the density functional theory (DFT) simulations and interactions. DOX loaded and unloaded LPHNs were administered orally to the rabbits for bioavailability and pharmacokinetic parameters determinations. The plasma concentration of DOX was determined through high performance liquid chromatography (HPLC). The average size of DOX-loaded LPHNs was 121.90 ± 3.0 nm. The drug loading of DOX was 0.391% ± 0.01 of aqueous dispersion, where its encapsulation efficiency was 95.5% ± 1.39. After oral administration of the DOX-LPHNs, the area under the plasma drug concentration-time curve (AUC) improved about 2-folds comparatively (p < 0.05). DFT simulations were used to understand the interactions of polymers with different sites of DOX molecule. The larger negative binding energies (-9.33 to -18.53 kcal/mol) of the different complexes evince that the polymers have stronger affinity to bind with the DOX molecule while the negative values shows that the process is spontaneous, and the synthesis of DOX-LPHNs is energetically favorable. It was concluded that DOX-LPHNs provides a promising new formulation that can enhance the oral bioavailability, which have optimized compatibilities and improve the pharmacokinetic of DOX after oral administration.

Application of nano-antibiotics in the diagnosis and treatment of infectious diseases

Infectious diseases are the leading cause of death worldwide. Thus, nanotechnology provides an excellent opportunity to treat drug-resistant microbial infections. Numerous antibiotics have been used to inhibit the growth and kill of microbes, but the development of resistance and the emergence of side effects have severely limited the use of these agents. Due to the development of the nanotechnology, nanoparticles are widely used as antimicrobials. Silver and chitosan nanoparticles have antifungal, antiviral and antibacterial properties, and many studies confirm the antifungal properties of silver nanoparticles. Nowadays, the use of nanoparticles in the diagnosis and treatment of infectious diseases has developed due to less side effects and also the help of these particles in effective drug delivery to the target tissue. Liposomes are also used as carriers of drug delivery, genes, and modeling of cell membranes in both animals and humans. The ability of these liposomes to encapsulate large amounts of drugs, minimize unwanted side effects, high effectiveness and low toxicity has attracted the interest of researchers. This review article examines recent efforts by researchers to identify and treat infectious diseases using antimicrobial nanoparticles and drug nano-carriers.

Nanotechnology: A Promising Targeted Drug Delivery System for Brain Tumours and Alzheimer's Disease

Nanotechnology is the process of modulating shape and size at the nanoscale to design and manufacture structures, devices, and systems. Nanotechnology's prospective breakthroughs are incredible, and some cannot even be comprehended right now. The blood-brain barrier, which is a prominent physiological barrier in the brain, limits the adequate elimination of malignant cells by changing the concentration of therapeutic agents at the target tissue. Nanotechnology has sparked interest in recent years as a way to solve these issues and improve drug delivery. Inorganic and organic nanomaterials have been found to be beneficial for bioimaging approaches and controlled drug delivery systems. Brain cancer (BC) and Alzheimer's disease (AD) are two of the prominent disorders of the brain. Even though the pathophysiology and pathways for both disorders are different, nanotechnology with common features can deliver drugs over the BBB, advancing the treatment of both disorders. This innovative technology could provide a foundation for combining diagnostics, treatments, and delivery of targeted drugs to the tumour site, further supervising the response and designing and delivering materials by employing atomic and molecular elements. There is currently limited treatment for Alzheimer's disease, and reversing further progression is difficult. Recently, various nanocarriers have been investigated to improve the bioavailability and efficacy of many AD treatment drugs. Nanotechnology-assisted drugs can penetrate the BBB and reach the target tissue. However, further research is required in this field to ensure the safety and efficacy of drug-loaded nanoparticles. The application of nanotechnology in the diagnosis and treatment of brain tumours and Alzheimer's disease is briefly discussed in this review.

Tissue Distribution, Histopathological and Genotoxic Effects of Magnetite Nanoparticles on Ehrlich Solid Carcinoma

Nanoparticles can potentially cause adverse effects on cellular and molecular level. The present study aimed to investigate the histopathological changes and DNA damage effects of magnetite nanoparticles (MNPs) on female albino mice model with Ehrlich solid carcinoma (ESC). Magnetite nanoparticles coated with L-ascorbic acid (size ~ 25.0 nm) were synthesized and characterized. Mice were treated with MNPs day by day, intraperitoneally (IP), intramuscularly (IM), or intratumorally (IT). Autopsy samples were taken from the solid tumor, thigh muscle, liver, kidney, lung, spleen, and brain for assessment of iron content, histopathological examination, and genotoxicity using comet assay. The liver, spleen, lung, and heart had significantly higher iron content in groups treated IP. On the other hand, tumor, muscles, and the liver had significantly higher iron content in groups treated IT. MNPs induced a significant DNA damage in IT treated ESC. While a significant DNA damage was detected in the liver of the IP treated group, but no significant DNA damage could be detected in the brain. Histopathological findings in ESC revealed a marked tumor necrosis, 50% in group injected IT but 40% in group injected IP and 20% only in untreated tumors. Other findings include inflammatory cell infiltration, dilatation, and congestion of blood vessels of different organs of treated groups in addition to appearance of metastatic cancer cells in the liver of non-treated tumor group. MNPs could have an antitumor effect but it is recommended to be injected intratumorally to be directed to the tumor tissues and reduce its adverse effects on healthy tissues.

Micro- and Nanosized Carriers for Nose-to-Brain Drug Delivery in Neurodegenerative Disorders

Neurodegenerative disorders (NDs) have become a serious health problem worldwide due to the rapid increase in the number of people that are affected and the constantly aging population. Among all NDs, Alzheimer’s and Parkinson’s disease are the most common, and many efforts have been made in the development of effective and reliable therapeutic strategies. The intranasal route of drug administration offers numerous advantages, such as bypassing the blood–brain barrier and providing a direct entrance to the brain through the olfactory and trigeminal neurons. The present review summarizes the available information on recent advances in micro- and nanoscale nose-to-brain drug-delivery systems as a novel strategy for the treatment of Alzheimer’s and Parkinson’s disease. Specifically, polymer- and lipid-base micro- and nanoparticles have been studied as a feasible approach to increase the brain bioavailability of certain drugs. Furthermore, nanocomposites are discussed as a suitable formulation for administration into the nasal cavity.

Subchronic Toxicity Evaluation of Aluminum Oxide Nanoparticles in Rats Following 28-Day Repeated Oral Administration

Several studies on the potential adverse effects of aluminum oxide nanoparticles (Al₂O₃NPs) have reported conflicting results. The present study investigated the potential adverse effects of Al₂O₃NPs in Sprague-Dawley rats following 28-day repeated oral administration. In addition, we aimed to determine the target organ and no-observed-adverse-effect level (NOAEL) of Al₂O₃NPs. Al₂O₃NPs was administered once daily by gavage to male and female rats at dose levels of 0, 500, and 1000 mg/kg/day for 28 days. There were no treatment-related adverse effects as indicated by the clinical signs, body weight, food consumption, urinalysis, ophthalmology, hematology, serum biochemistry, gross pathology, organ weight, and histopathology at all the tested doses. Under the experimental conditions of the present study, 28-day repeated oral administration of Al₂O₃NPs at doses of up to 1000 mg/kg/day did not induce any treatment-related systemic toxicity in male and female rats. The NOAEL of Al₂O₃NPs was set at 1000 mg/kg/day in both male and female rats and no target organs were identified.

Zinc Oxide Nanoparticles Induce DNA Damage in Sand Dollar Scaphechinus mirabilis Sperm

Products containing nanomaterials are becoming more and more common in everyday life. Zinc oxide nanoparticles (ZnO NPs), meanwhile, are among the most widely used NPs. However, their genotoxic effect on the germ products of marine organisms is poorly understood. Therefore, the effects of ZnO NPs and zinc ions (20, 50, 100, 200 µg/L) on the sperm of sand dollar Scaphechinus mirabilis were compared. Comet assay showed that both tested pollutants caused an increase in DNA damage to 6.57 ± 2.41 and 7.42 ± 0.88% DNA in the comet tail, for zinc ions and ZnO NPs, respectively. Additionally, a different pattern was shown by the increase in DNA damage, with increasing concentration of pollutants, in different experimental groups.

Designing red-fluorescent superparamagnetic nanoparticles by conjugation with gold clusters

We report the study of gold clusters' attachment to magnetic nanoparticles by microwave processing for red-luminescent magnetic species formation.

Traditional herbal medicine and nanomedicine: Converging disciplines to improve therapeutic efficacy and human health

Traditional herbal medicine (THM), an ancient science, is a gift from nature. For thousands of years, it has helped humans fight diseases and protect life, health, and reproduction. Nanomedicine, a newer discipline has evolved from exploitation of the unique nanoscale morphology and is widely used in diagnosis, imaging, drug delivery, and other biomedical fields. Although THM and nanomedicine differ greatly in time span and discipline dimensions, they are closely related and are even evolving toward integration and convergence. This review begins with the history and latest research progress of THM and nanomedicine, expounding their respective developmental trajectory. It then discusses the overlapping connectivity and relevance of the two fields, including nanoaggregates generated in herbal medicine decoctions, the application of nanotechnology in the delivery and treatment of natural active ingredients, and the influence of physiological regulatory capability of THM on the in vivo fate of nanoparticles. Finally, future development trends, challenges, and research directions are discussed.

Norfloxacin Loaded Lipid Polymer Hybrid Nanoparticles for Oral Administration: Fabrication, Characterization, In Silico Modelling and Toxicity Evaluation

Norfloxacin (NOR), widely employed as an anti-bacterial drug, has poor oral bioavailability. Nano based drug delivery systems are widely used to overcome the existing oral bioavailability challenges. Lipid–Polymer Hybrid Nanoparticles (LPHNs) exhibit the distinctive advantages of both polymeric and liposomes nanoparticles, while excluding some of their disadvantages. In the current study, NOR loaded LPHNs were prepared, and were solid amorphous in nature, followed by in vitro and in vivo evaluation. The optimized process conditions resulted in LPHNs with the acceptable particle size 121.27 nm, Polydispersity Index (PDI) of 0.214 and zeta potential of −32 mv. The addition of a helper lipid, oleic acid, and polymers, ethyl cellulose, substantially increased the encapsulation efficiency (EE%) (65% to 97%). In vitro study showed a sustained drug release profile (75% within 12 h) for NOR LPHNs. The optimized NOR LPHNs showed a significant increase (p < 0.05) in bioavailability compared to the commercial product. From the acute toxicity study, the LD50 value was found to be greater than 1600 mg/kg. The molecular modelling studies substantiated the experimental results with the best combination of polymers and surfactants that produced highly stable LPHNs. Therefore, LPHNs proved to be a promising system for the delivery of NOR, as well as for other antibiotics and hydrophobic drugs.

Influence of Titanium Dioxide Nanoparticles on Human Health and the Environment

Nanotechnology has enabled tremendous breakthroughs in the development of materials and, nowadays, is well established in various economic fields. Among the various nanomaterials, TiO₂ nanoparticles (NPs) occupy a special position, as they are distinguished by their high availability, high photocatalytic activity, and favorable price, which make them useful in the production of paints, plastics, paper, cosmetics, food, furniture, etc. In textiles, TiO₂ NPs are widely used in chemical finishing processes to impart various protective functional properties to the fibers for the production of high-tech textile products with high added value. Such applications contribute to the overall consumption of TiO₂ NPs, which gives rise to reasonable considerations about the impact of TiO₂ NPs on human health and the environment, and debates regarding whether the extent of the benefits gained from the use of TiO₂ NPs justifies the potential risks. In this study, different TiO₂ NPs exposure modes are discussed, and their toxicity mechanisms—evaluated in various in vitro and in vivo studies—are briefly described, considering the molecular interactions with human health and the environment. In addition, in the conclusion of this study, the toxicity and biocompatibility of TiO₂ NPs are discussed, along with relevant risk management strategies.

Seaweed bioactive compounds: Promising and safe inputs for the green synthesis of metal nanoparticles in the food industry

Scientific research on developing and characterizing eco-friendly metal nanoparticles (NPs) is an active area experiencing currently a systematic and continuous growth. A variety of physical, chemical and more recently biological methods can be used for the synthesis of metal nanoparticles. Among them, reports supporting the potential use of algae in the NPs green synthesis, contribute with only a minor proportion, although seaweed was demonstrated to perform as a successful reducing and stabilizing agent. Thus, the first part of the present review depicts the up-to-date information on the use of algae extracts for the synthesis of metal nanoparticles, including a deep discussion of the certain advantages as well as some limitations of this synthesis route. In the second part, the available characterization techniques to unravel their inherent properties such as specific size, shape, composition, morphology and dispersibility are comprehensively described, to finally focus on the factors affecting their applications, bioactivity, potential toxic impact on living organisms and incorporation into food matrices or food packaging, as well as future prospects. The present article identifies the key knowledge gap in a systematic way highlighting the critical next steps in the green synthesis of metal NPs mediated by algae.

Synthesis, Characterization, Applications, and Toxicity of Green Synthesized Nanoparticles

Nanotechnology is a cutting-edge area with numerous industrial applications. Nanoparticles are structures that have dimensions ranging from 1-100 nm which exhibit significantly different mechanical, optical, electrical, and chemical properties when compared with their larger counterparts. Synthetic routes that use natural sources, such as plant extracts, honey, and microorganisms are environmentally friendly and low-cost methods that can be used to obtain nanoparticles. These methods of synthesis generate products that are more stable and less toxic than those obtained using conventional methods. Nanoparticles formed by titanium dioxide, zinc oxide, silver, gold, and copper, as well as cellulose nanocrystals are among the nanostructures obtained by green synthesis that have shown interesting applications in several technological industries. Several analytical techniques have also been used to analyze the size, morphology, hydrodynamics, diameter, and chemical functional groups involved in the stabilization of the nanoparticles as well as to quantify and evaluate their formation. Despite their pharmaceutical, biotechnological, cosmetic, and food applications, studies have detected their harmful effects on human health and the environment; and thus, caution must be taken in uses involving living organisms. The present review aims to present an overview of the applications, the structural properties, and the green synthesis methods that are used to obtain nanoparticles, and special attention is given to those obtained from metal ions. The review also presents the analytical methods used to analyze, quantify, and characterize these nanostructures.

Investigating the remediation potential of iron oxide nanoparticles in Cu-polluted soil-plant systems: coupled geochemical, geophysical and biological approaches

Although the use of iron oxide nanoparticles (IONPs) has high potential in remediation and agriculture, a major hindrance to their use includes the risk of contamination of soil and water resources with underexplored effects of IONPs on biota. The fate, phytotoxicity and remediation potential of IONPs are investigated with soil column experiments using 7 nm-sized magnetite (Fe₃O₄) nanoparticles (magnNPs) and sunflower (Helianthus annuus). Control soil, magnNP-containing soil (10 g magnNPs per kg soil), copper-polluted soil (500 mg Cu per kg soil) and copper-polluted soil containing magnNPs (10 g magnNPs per kg soil and 500 mg Cu per kg soil) support sunflower growth for 57 and 95 days. In magnNP-exposed plants, the occurrence of magnNPs does not affect the growth of the vegetative aerial parts and photosynthetic efficiency. Decreased lipid peroxidation indicates an enhanced antioxidant enzymatic response of magnNP-exposed plants. In plants grown in Cu- and magnNP-Cu-soils, the physiological and biochemical impacts of excess copper are clearly identified, resulting in growth retardation, decreased pigment contents and photosynthetic efficiency, and increased lipid peroxidation and peroxidase (POD) activities. Based on magnetic susceptibility, a higher amount of magnNPs is detected after 57 days in the roots of magnNP-exposed plants (1400 mg kg^-1) than in the roots of magnNP-Cu-exposed plants (920 mg kg^-1). In the latter, magnNP internalization is likely hampered because of the plants' physiological responses to Cu toxicity. At the working Cu and magnNP concentrations, magnNPs neither decrease Cu accumulation in the plant tissues nor alleviate the overall growth retardation of sunflowers and certain phytotoxic effects induced by excess Cu. However, this study highlights several positive environmental aspects relative to magnNP use, including the harmless effects of magnNPs on sunflowers (1% magnNPs in soil) and the ability of magnNPs to influence Cu mobility in the soil (which could be even more pronounced at lower Cu concentration).

Review on Polymer, Ceramic and Composite Materials for CAD/CAM Indirect Restorations in Dentistry-Application, Mechanical Characteristics and Comparison

The aim of this review article is to present various material groups, including ceramics, composites and hybrid materials, currently utilized in the field of CAD/CAM. The described technology is amongst the most important in modern prosthetics. Materials that are applicable in this technique are constantly tested, evaluated and improved. Nowadays, research on dental materials is carried out in order to meet the increasing demand on highly aesthetic and functional indirect restorations. Recent studies present the long-term clinical success of restorations made with the help of both ceramic and composite materials in the CAD/CAM method. However, new materials are developed and introduced that do not have long-term in vivo observations. We can outline a monolithic polymer-infiltrated ceramic network and zirconia teeth support that show promising results to date but require further assessment. The materials will be compared with regard to their mechanical and clinical properties, purpose, advantages and limitations.

Hollow iron oxide nanomaterials: synthesis, functionalization, and biomedical applications

Hollow iron oxide nanoparticles (NPs) are an attractive class of hollow nanostructures that have received significant attention in the biomedical field due to their low toxicity, good biocompatibility, and intrinsic magnetic nature. We review the recent advances in the preparation, surface functionalization, and biomedical applications of hollow iron oxide NPs. Hollow iron oxide NPs are generally synthesized by the following five strategies, including the Kirkendall effect, galvanic replacement, chemical etching, nano template-mediated, and hydrothermal/solvothermal routes. We also summarize the general strategies for iron oxide NP surface functionalization. Moreover, various promising biomedical applications of hollow iron oxide NPs, including magnetic resonance imaging, drug delivery, and cancer therapy, are highlighted in detail. Finally, perspectives of hollow iron oxide NPs are provided.

A review on the biological effects of nanomaterials on silkworm (Bombyx mori)

The production of high-quality silkworm silk is of importance in sericulture in addition to the production of biomass, silk proteins, and animal feed. The distinctive properties of nanomaterials have the potential to improve the development of various sectors including medicine, cosmetics, and agriculture. The application of nanotechnology in sericulture not only improves the survival rate of the silkworm, promotes the growth and development of silkworm, but also improves the quality of silk fiber. Despite the positive contributions of nanomaterials, there are a few concerns regarding the safety of their application to the environment, in humans, and in experimental models. Some studies have shown that some nanomaterials exhibit toxicity to tissues and organs of the silkworm, while other nanomaterials exhibit therapeutic properties. This review summarizes some reports on the biological effects of nanomaterials on silkworm and how the application of nanomaterials improves sericulture.

Current understanding of nanoparticle toxicity mechanisms and interactions with biological systems

Nanotechnology is an emerging science involving the manipulation of matter on the nanometer scale.

Recent Advances in Nanotherapeutic Interventions for the Treatment of Alzheimer's Disease

Alzheimer's disease (AD), with impairment of learning and memory as the common clinical manifestations, is one of the most challenging diseases affecting individuals, their families and society as a whole. The fact that its prevalence is escalating rapidly, with the total number of AD patients estimated to reach 115.4 million by 2050, has made the disease a very challenging ailment worldwide. Several biological barriers like the bloodbrain barrier (BBB), drug efflux by P-glycoprotein and the blood-cerebrospinal fluid barrier restrict the delivery of conventional AD drugs to the central nervous system (CNS), thereby limiting their effectiveness. In order to overcome the above physiological barriers, the development of nanomedicines has been extensively explored. The present review provides an insight into the pathophysiology of AD and risk factors associated with AD. Besides, various nanoformulations reported in the literature for the diagnosis and treatments of AD have been classified and summarised. The patented nanoformulations for AD and details of nanoformulations which are in clinical trials are also mentioned. The review would be helpful to researchers and scientific community by providing them with information related to the recent advances in nanointerventions for the diagnosis and treatment of AD, which they can further explore for better management of the disease. However, although the nanotherapeutics for managing AD have been extensively explored, the factors which hinder their commercialisation, the toxicity concern being one of them, need to be addressed so that effective nanotherapeutics for AD can be developed for clinical use.

Biocompatibility of magnetic nanoparticles coating with polycations using A549 cells

Fe₃O₄ nanoparticles were obtained by chemical coprecipitation of iron chloride and sodium hydroxide. The morphology and sizes of the obtained nanoparticles were characterized using laser Doppler velocimetry, transmission electron and atomic force microscopy. Then the nanoparticles were stabilized by three polycations (polyethylenimine (PEI), poly(allylamine hydrochloride) (PAH), poly(diallyldimethylammonium chloride) (PDADMAC)) to increase their biocompatibility. The cytotoxicity of the obtained polymer-stabilized nanoparticles was studied using a human lung carcinoma cell line (A549). The biodistribution of nanoparticles stabilized by polycations in human lung carcinoma cells was analyzed by transmission electron microscopy, and the toxicity of nanomaterials was evaluated using toxicity tests and flow cytometry. As a result, the most biocompatible nanoparticle-biopolymer complex was identified. PAH stabilized magnetic nanoparticles demonstrated the best biocompatibility, and the PEI-magnetic nanoparticle complex was the most toxic.

Nanomaterials in Dentistry: State of the Art and Future Challenges

Nanomaterials are commonly considered as those materials in which the shape and molecular composition at a nanometer scale can be controlled. Subsequently, they present extraordinary properties that are being useful for the development of new and improved applications in many fields, including medicine. In dentistry, several research efforts are being conducted, especially during the last decade, for the improvement of the properties of materials used in dentistry. The objective of the present article is to offer the audience a complete and comprehensive review of the main applications that have been developed in dentistry, by the use of these materials, during the last two decades. It was shown how these materials are improving the treatments in mainly all the important areas of dentistry, such as endodontics, periodontics, implants, tissue engineering and restorative dentistry. The scope of the present review is, subsequently, to revise the main applications regarding nano-shaped materials in dentistry, including nanorods, nanofibers, nanotubes, nanospheres/nanoparticles, and zeolites and other orders porous materials. The results of the bibliographic analysis show that the most explored nanomaterials in dentistry are graphene and carbon nanotubes, and their derivatives. A detailed analysis and a comparative study of their applications show that, although they are quite similar, graphene-based materials seem to be more promising for most of the applications of interest in dentistry. The bibliographic study also demonstrated the potential of zeolite-based materials, although the low number of studies on their applications shows that they have not been totally explored, as well as other porous nanomaterials that have found important applications in medicine, such as metal organic frameworks, have not been explored. Subsequently, it is expected that the research effort will concentrate on graphene and zeolite-based materials in the coming years. Thus, the present review paper presents a detailed bibliographic study, with more than 200 references, in order to briefly describe the main achievements that have been described in dentistry using nanomaterials, compare and analyze them in a critical way, with the aim of predicting the future challenges.

Toxicity and mechanism of mesoporous silica nanoparticles in eyes

The study on the safety of nanomaterials in eyes is still in its early stages. In this study, we put our focus on the effect of one important nanoparticle feature - large surface area - to assess eye safety. To this end, mesoporous silica nanoparticles (MSiNPs) were for the first time employed as a model to evaluate their toxicity in eyes. The porosity of the MSiNPs endows them with a large surface area and the ability to attach to surrounding chemical or biological molecules, further enhancing their surface reactivity and toxic effects. Therefore, to better mimic MSiNP exposure in real environments, we also introduced other hazardous substances such as silver ions (Ag+) to the system and then investigated their synergistic nanotoxicity. Our results showed that the exposure to MSiNPs-Ag+ and even Ag+ at a safe dose, resulted in more significant toxicity than the MSiNPs alone, as evidenced from cell viability, apoptosis, reactive oxygen species (ROS) production, and DNA damage experiments. RNA-Sequencing analysis revealed that the mRNA surveillance signalling pathway plays a unique role in regulating MSiNPs-Ag+-induced cytotoxicity. Besides this, severe corneal damage and dry eye were observed in rat models upon exposure to MSiNPs-Ag+ compared to MSiNPs. Most importantly, we also proposed a protein corona-based therapy to treat MSiNP-induced corneal disease, where the corneal damage could be rescued by fetal bovine serum (FBS) treatment.

Nanotoxicity: a challenge for future medicine

Background/aim

Due to nanomaterials’ potential benefits for diagnosis and treatment, they are widely used in medical applications and personal care products. Interaction of nanomaterials, which are very small in size, with tissue, cell and microenvironment, can reveal harmful effects that cannot be created with chemically identical and larger counterparts in biological organisms. In this review, a challenge for future medicine, nanotoxicity of nanomaterials is discussed.

Materials and methods

A detailed review of related literature was performed and evaluated as per medical applications of nanomaterials their toxicity.

Results and conclusion

Most authors state “the only valid technology will be nanotechnology in the next era”; however, there is no consensus on the impact of this technology on humankind, environment and ecological balance. Studies dealing with the toxic effect of nanomaterials on human health have also varied with developing technology. Nanotoxicology studies such as in vivo-like on 3D human organs, cells, advanced genetic studies, and -omic approaches begin to replace conventional methods. Nanotoxicity and adverse effects of nanomaterials in exposed producers, industry workers, and patients make nanomaterials a double-edged sword for future medicine. In order to control and tackle related risks, regulation and legislations should be implemented, and researchers have to conduct joint multidisciplinary studies in various fields of medical sciences, nanotechnology, nanomedicine, and biomedical engineering.

Biomedical Applications of TiO2 Nanostructures: Recent Advances

Titanium dioxide (TiO2) nanostructures are one of the most plentiful compounds that have emerged in various fields of technology such as medicine, energy and biosensing. Various TiO2 nanostructures (nanotubes [NTs] and nanowires) have been employed in photoelectrochemical (PEC) biosensing applications, greatly enhancing the detection of targets. TiO2 nanostructures, used as reinforced material or coatings for the bare surface of titanium implants, are excellent additive materials to compensate titanium implants deficiencies-like poor surface interaction with surrounding tissues-by providing nanoporous surfaces and hierarchical structures. These nanostructures can also be loaded by diversified drugs-like osteoporosis drugs, anticancer and antibiotics-and used as local drug delivery systems. Furthermore, TiO2 nanostructures and their derivatives are new emerging antimicrobial agents to overcome human pathogenic microorganisms. However, like all other nanomaterials, toxicity and biocompatibility of TiO2 nanostructures must be considered. This review highlights recent advances, along with the properties and numerous applications of TiO2-based nanostructure compounds in nano biosensing, medical implants, drug delivery and antibacterial fields. Moreover, in the present study, some recent advances accomplished on the pharmaceutical applications of TiO2 nanostructures, as well as its toxicity and biocompatibility, are presented.

Effect of nanoscale bioactive glass with radial spherical particles on osteogenic differentiation of rat bone marrow mesenchymal stem cells

To validate the feasibility of two types of bioactive glass that contains spherical and radical spherical nano-sized particles in promoting bone repair, we hypothesize that radical spherical nano-sized particles have higher bone repair effectiveness than spherical one due to the physicochemical properties. We rigorously compared the physicochemical properties and bioactivities of these two types of bioactive glass. Specifically, we measured the size, surface morphology, concentration of ionic-dissolution products, bioactivity, and biological effects of two groups of bioactive glass on rat bone marrow mesenchymal stem cells (rBMSCs) and evaluate their effect on proliferation and osteogenic differentiation of rBMSCs in vitro. We observed that spherical nano-bioactive glass (SNBG) was spherical with smooth boundary, while the radial spherical nano-bioactive glass (RSNBG) had radial pore on the surface of particle boundary. When the two materials were immersed in simulated body fluid for 24 h, RSNBG produced more and denser hydroxyapatite carbonate than SNBG. The concentration of Ca and Si ions in RSNBG 24 h extract is higher than that of SNBG, while the concentration of P ions is lower. Proliferation, alkaline phosphatase (ALP) activity, intracellular Ca ion concentrations defined as the number of mineralized nodules produced, and the expression of osteogenic genes were significantly higher in rBMSCs co-cultured with 50 µg/mL RSNBG than SNBG. Overall, these results validated our hypothesis that RSNBG can provide better benefit than SNBG for inducing proliferation and osteogenic differentiation in rBMSCs, in turn suggested the feasibility of this RSNBG in further studies and utilization toward the ends of improved bone repair effectiveness.

Neurotoxicity mediated by oxidative stress caused by titanium dioxide nanoparticles in human neuroblastoma (SH-SY5Y) cells

BACKGROUND

Titanium is widely used in biomedicine. Due to biotribocorrosion, titanium dioxide (TiO₂) nanoparticles (NPs) can be released from the titanium implant surface, enter the systemic circulation, and migrate to various organs and tissues including the brain. A previous study showed that 5 nm TiO₂ NPs reached the highest concentration in the brain. Even though TiO₂ NPs are believed to possess low toxicity, little is known about their neurotoxic effects. The aim of the study was to evaluate in vitro the effects of 5 nm TiO₂ NPs on a human neuroblastoma (SH-SY5Y) cell line.

METHODS

Cell cultures were divided into non-exposed and exposed to TiO₂ NPs for 24 h. The following were evaluated: reactive oxygen species (ROS) generation, apoptosis, cellular antioxidant response, endoplasmic reticulum stress and autophagy.

RESULTS

Exposure to TiO₂ NPs induced ROS generation in a dose dependent manner, with values reaching up to 10 fold those of controls (p < 0.001). Nrf2 nuclear localization and autophagy, also increased in a dose dependent manner. Apoptosis increased by 4- to 10-fold compared to the control group, depending on the dose employed.

CONCLUSIONS

Our results show that TiO₂ NPs cause ROS increase, induction of ER stress, Nrf2 cytoplasmic translocation to the nucleus and apoptosis. Thus, neuroblastoma cell response to TiO₂ NPs may be associated with an imbalance of the oxidative metabolism where endoplasmic reticulum-mediated signal pathway seems to be the main neurotoxic mechanism.

Nanomedicinal strategies as efficient therapeutic interventions for delivery of cancer vaccines

The applications of gene therapy-based treatment of cancers were started almost two decades back as a boon over the chemotherapeutic treatment strategies. Gene therapy helps in correcting the genetic sequences for treatment of cancers, thus also acts like a vaccine to induce the cellular and humoral immunity. However, the cancer vaccines typically suffer from a series of biopharmaceutical challenges due to poor solubility, low systemic availability and lack of targeting ability. Owing to these challenges, the physicians and pharmaceutical scientists have explored the applications of nanocarriers as quite promising systems for effective treatment against the tumors. A series of nanotherapeutic systems are available to date for diverse drug therapy applications. Systematic understanding on the preparation, evaluation and application of nanomedicines as a carrier system for delivering the cancer vaccines is highly important. The present review article provides an in-depth understanding on the challenges associated with cancer vaccine delivery and current opportunities with diverse nanomedicinal carriers being available for treatment of cancers.

How toxic is a non-toxic nanomaterial: Behaviour as an indicator of effect in Danio rerio exposed to nanogold

Gold nanoparticles are used as drug delivery vectors based on the assumption that they have low toxicity. Literature has, however, produced conflicting results over the last few years. As such, this study aimed to investigate the toxicological effects of nanogold (nAu) on several indicators that range from subcellular to whole-organism level. Gene regulation, changes in oxidative stress biomarkers and swimming performance were assessed in Danio rerio (zebrafish) following exposures to nAu. Adult zebrafish were exposed in vivo to nAu for 96 h and swimming performance measured post-exposure. Liver tissue was collected for DNA microarray and Real-Time Polymerase Chain Reactions (RT-PCR) analyses to determine changes in gene expression (catalase, superoxide dismutase and metallothioneins) and protein biomarker analyses (catalase, superoxide dismutase, acetylcholine esterase, malondialdehyde, cellular energy allocation and metallothionein) were performed on whole-body samples. Swimming behaviour was assessed in 1.1 L Tecniplast™ tanks for a period of six hours and videos were analysed using Noldus EthoVision software. Critical swimming speed was measured in a Loligo® swimming tunnel. The DNA microarray revealed that fish exposed to 20 mg/L differed most from the control group. At 20 mg/L there was a significant increase in gene expression for all genes analysed but this didn't translate to significant responses in protein biomarker levels except for an increase in protein carbonyl formation. The behaviour results demonstrated significant changes in distance moved, swimming speed, acceleration bouts, zone alterations and time spent within the top zone - responses that are usually observed in fish responding to toxicological stress. Furthermore, the critical swimming speed of exposed fish was decreased significantly compared to the control. Since swimming performance and social interaction among zebrafish is essential to their survival, whole-organism behaviour that suggests a toxicological response after exposure to nAu is in agreement with the genetic responses measured in this study.

Safety Assessment of Nanomaterials to Eyes: An Important but Neglected Issue

The production and application of nanomaterials have grown tremendously during last few decades. The widespread exposure of nanoparticles to the public is provoking great concerns regarding their toxicity to the human body. However, in comparison with the extensive studies carried out to examine nanoparticle toxicity to the human body/organs, one especially vulnerable organ, the eye, is always neglected. Although it is a small part of the body, 90% of outside information is obtained via the ocular system. In addition, eyes usually directly interact with the surrounding environment, which may get severer damage from toxic nanoparticles compared to inner organs. Therefore, the study of assessing the potential nanoparticle toxicity to the eyes is of great importance. Here, the recent advance of some representative manufactured nanomaterials on ocular toxicity is summarized. First, a brief introduction of ocular anatomy and disorders related to particulate matter exposure is presented. Following, the factors that may influence toxicity of nanoparticles to the eye are emphasized. Next, the studies of representative manufactured nanoparticles on eye toxicity are summarized and classified. Finally, the limitations that are associated with current nanoparticle-eye toxicity research are proposed.

Development of Smart Composites Based on Doped-TiO2 Nanoparticles with Visible Light Anticancer Properties

In this study, the synthesis of smart, polymerically embedded titanium dioxide (TiO2) nanoparticles aimed to exhibit photo-induced anticancer properties under visible light irradiation is investigated. The TiO2 nanoparticles were prepared by utilizing the sol gel method with different dopants, including nitrogen (N-doped), iron (Fe-doped), and nitrogen and iron (Fe,N-doped). The dopants were embedded in an interpenetrating (IP) network microgel synthesized by stimuli responsive poly (N-Isopropylacrylamide-co-polyacrylicacid)-pNipam-co-PAA forming composite particles. All the types of produced particles were characterized by X-ray powder diffraction, micro-Raman, Fourier-transform infrared, X-ray photoelectron, ultra-violet-visible spectroscopy, Field Emission Scanning Electron, Transmission Electron microscopy, and Dynamic Light Scattering techniques. The experimental findings indicate that the doped TiO2 nanoparticles were successfully embedded in the microgel. The N-doped TiO2 nano-powders and composite particles exhibit the best photocatalytic degradation of the pollutant methylene blue under visible light irradiation. Similarly, the highly malignant MDA-MB-231 breast cancer epithelial cells were susceptible to the inhibition of cell proliferation at visible light, especially in the presence of N-doped powders and composites, compared to the non-metastatic MCF-7 cells, which were not affected.

Magnetic nanoparticles decorated with PEGylated curcumin as dual targeted drug delivery: Synthesis, toxicity and biocompatibility study

The problems associated with hydrophobic anticancer drugs are among the most important challenges to achieve efficient therapeutics for cancer treatment. In this study, PEGylated curcumin was used as the surface modification of magnetic nanoparticles (MNP@PEG-Cur) in order to simultaneously take advantage of magnetic targeting characteristic of nanoparticles and PEG conjugated drug. Curcumin was conjugated through EDC/NHS chemistry to the PEG hydroxyl functional groups, and then physically decorated on the surface of magnetic nanoparticles (MNP). The analysis of the conjugate and nanoparticles by FT-IR, ¹HNMR, FE-SEM, TEM, EDX, TGA and VSM confirmed the successful synthesis and proper physicochemical properties of MNP@PEG-Cur nanoparticles. The carrier showed pH dependent drug release profile with higher drug release at acidic media (pH = 5.4) compared to neural condition (pH = 7.4). In addition, LD₅₀ and hemolysis assay confirmed the biocompatibility of MNP@PEG-Cur. The cell viability assay also revealed that neither carrier, nor curcumin-loaded nanoparticles are cytotoxic at physiologic pH (7.4).

Understanding the interaction of single-walled carbon nanotube (SWCNT) on estrogen receptor: A combined molecular dynamics and experimental study

Considering the large-scale production of diversified nanomaterials, it is paramount importance to unravel the structural details of interactions between nanoparticles and biological systems, and thus to explore the potential adverse impacts of nanoparticles. Estrogen receptors (ER) is one of the most important receptor of human reproductive system and the binding of carbon nanotubes to estrogen receptors was the possible trigger leading to the reproductive toxicity of carbon nanotubes. Thus, with single-walled carbon nanotube (SWCNT) treated as model nanomaterials, a combination of in vivo experiments, spectroscopy assay and molecular dynamic modeling was applied to help us unravel some important issues on the binding characterization between SWCNT and the ligand binding domain (LBD) of ER alpha (ERα). The fluorescence assay and molecular dynamics simulations together validated the binding of SWCNT to ERα, suggesting the possible molecular initiating event. As a consequence, SWCNT binding led to a conformational change on tertiary structure levels and hydrophobic interaction was recognized as the driving force governing the binding behavior between SWCNT and LBD of ERα. A in vivo process presented that the exposure of SWCNT increased ERα expression from 26.43 pg/ml to 259.01 pg/ml, suggesting a potential estrogen interference effects of SWCNT. Our study offers insight on the binding of SWCNT and ERα LBD at atomic level, helpful to accurately evaluate the potential health risks of SWCNT.

ZnO nanoparticles inhibit the activity of Porphyromonas gingivalis and Actinomyces naeslundii and promote the mineralization of the cementum

Background

Zinc oxide nanoparticles (ZnONPs) have been widely studied as bactericidal reagents. However, it is still challenging to use ZnONPs as a root canal sealant to eliminate infecting microorganisms in the root canal system. This study aimed at understanding the antibacterial and biofilm effects of ZnONPs in the infected root canal and their effect on cell function.

Methods

This study aimed to develop a better understanding of the antibacterial effects of ZnONPs in the infected root canal and their effect on cell function. Experiments were performed in two stages; the first stage included inhibition zone tests and the minimum inhibitory concentration (MIC) test, which were performed to examine the antibacterial activity of ZnONPs against Porphyromonas gingivalis (P. gingivalis) and Actinomyces Naeslundii (A. naeslundii) bacteria in vitro. ZnONPs were further evaluated for their biocompatibility using normal mouse NIH3T3 and OCCM-30 cells by the cell-based MTT assay. In addition, the influence of ZnONPs on matrix metalloproteinases in NIH3T3 cells and their inhibiting factors (Mmp13 and Timp1) were measured using the real-time PCR technique and western blot method.

Results

The MIC of ZnONPs against P. gingivalis and A. naeslundii were confirmed to be 10 μg/mL and 40 μg/mL, respectively. The MTT assay showed that ZnONPs were nontoxic. The RT-PCR and western blotting results showed that Mmp13 was downregulated and Timp1 expression was increased. Meanwhile, ZnONPs were shown to increase the expression of the OCCM-30 osteogenesis-related factors Bsp and Runx2. Finally, there was no significant change in the morphology of NIH3T3 and OCCM-30 cells after the addition of different concentrations of ZnONPs for different periods of time.

Conclusion

ZnONPs have excellent antibacterial activity against P. gingivalis and A. naeslundii and have low cell cytotoxicity in vitro.

Targeting EGFR of triple-negative breast cancer enhances the therapeutic efficacy of paclitaxel- and cetuximab-conjugated nanodiamond nanocomposite

Breast cancer is the most common malignancy and a leading cause of cancer-related mortality among women worldwide. Triple-negative breast cancer (TNBC) is characterized by the lack of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (HER2). However, epidermal growth factor receptor (EGFR) is highly expressed in most of the TNBCs, which may provide a potential target for EGFR targeting therapy. Nanodiamond (ND) is a carbon-based nanomaterial with several advantages, including fluorescence emission, biocompatibility, and drug delivery applications. In this study, we designed a nanocomposite by using ND conjugated with paclitaxel (PTX) and cetuximab (Cet) for targeting therapy on the EGFR-positive TNBC cells. ND-PTX inhibited cell viability and induced mitotic catastrophe in various human breast cancer cell lines (MDA-MB-231, MCF-7, and BT474); in contrast, ND alone did not induce cell death. ND-PTX inhibited the xenografted human breast tumors in nude mice. We further investigated ND-PTX-Cet drug efficacy on the TNBC of MDA-MB-231 breast cancer cells. ND-PTX-Cet could specifically bind to EGFR and enhanced the anticancer effects including drug uptake levels, mitotic catastrophe, and apoptosis in the EGFR-expressed MDA-MB-231 cells but not in the EGFR-negative MCF-7 cells. In addition, ND-PTX-Cet increased the protein levels of active caspase-3 and phospho-histone H3 (Ser10). Furthermore, ND-PTX-Cet showed more effective on the reduction of TNBC tumor volume by comparison with ND-PTX. Taken together, these results demonstrated that ND-PTX-Cet nanocomposite enhanced mitotic catastrophe and apoptosis by targeting EGFR of TNBC cells, which can provide a feasible strategy for TNBC therapy. STATEMENT OF SIGNIFICANCE: Current TNBC treatment is ineffective against the survival rate of TNBC patients. Therefore, the development of new treatment strategies for TNBC patients is urgently needed. Here, we have designed a nanocomposite by targeting on the EGFR of TNBC to enhance therapeutic efficacy by ND-conjugated PTX and Cet (ND-PTX-Cet). Interestingly, we found that the co-delivery of Cet and PTX by ND enhanced the apoptosis, mitotic catastrophe and tumor inhibition in the EGFR-expressed TNBC in vitro and in vivo. Consequently, this nanocomposite ND-PTX-Cet can be applied for targeting EGFR of human TNBC therapy.

Synthesis and characterization of a novel organosilane-functionalized chitosan nanocarrier as an efficient gene delivery system: Expression of green fluorescent protein

Semi-essential arginine amino acid was selected to synthesis an organosilane linker for modifying chitosan biopolymer. The novel organosilane linker which was chemically synthesized by reaction of arginine with 3‑chloropropyl trimethoxy silane, covalently bonded to the chitosan amino group. The chemical structure of resulting nanocarrier was characterized by ¹H NMR, wide-X-ray diffraction, TEM, FESEM and EDX. A maximum retardation capacity of the nanocarrier to the plox plasmid was obtained 3 at physiological pH (7.4). The mean of cell viability and cytotoxicity of the nanocarrier was determined 85% by MTT assay. In addition, the gene transfection of the nanocarrier was obtained top of 20% gene expression. The studies have shown very good DNase 1 enzyme protection of plasmid by the nanocarrier.