Preparation and characterization of protein-loaded N-trimethyl chitosan nanoparticles as nasal delivery system

Nanoplatform Based Intranasal Vaccines: Current Progress and Clinical Challenges

Multiple vaccine platforms have been employed to develop the nasal SARS-CoV-2 vaccines in preclinical studies, and the dominating pipelines are viral vectored as protein-based vaccines. Among them, several viral vectored-based vaccines have entered clinical development. Nevertheless, some unsatisfactory results were reported in these clinical studies. In the face of such urgent situations, it is imperative to rapidly develop the next-generation intranasal COVID-19 vaccine utilizing other technologies. Nanobased intranasal vaccines have emerged as an approach against respiratory infectious diseases. Harnessing the power of nanotechnology, these vaccines offer a noninvasive yet potent defense against pathogens, including the threat of COVID-19. The improvements made in vaccine mucosal delivery technologies based on nanoparticles, such as lipid nanoparticles, polymeric nanoparticles, inorganic nanoparticles etc., not only provide stability and controlled release but also enhance mucosal adhesion, effectively overcoming the limitations of conventional vaccines. Hence, in this review, we overview the evaluation of intranasal vaccine and highlight the current barriers. Next, the modern delivery systems based on nanoplatforms are summarized. The challenges in clinical application of nanoplatform based intranasal vaccine are finally discussed.

Lysosomal Activation Mediated by Endocytosis in J774 Cell Culture Treated with N-Trimethyl Chitosan Nanoparticles

Safety and effectiveness are the cornerstone objectives of nanomedicine in developing nanotherapies. It is crucial to understand the biological interactions between nanoparticles and immune cells. This study focuses on the manufacture by the microfluidic technique of N-trimethyl chitosan/protein nanocarriers and their interaction with J774 cells to elucidate the cellular processes involved in absorption and their impact on the immune system, mainly through endocytosis, activation of lysosomes and intracellular degradation. TEM of the manufactured nanoparticles showed spherical morphology with an average diameter ranging from 36 ± 16 nm to 179 ± 92 nm, depending on the concentration of the cargo protein (0, 12, 55 μg/mL). FTIR showed the crosslinking between N-trimethyl chitosan and the sodium tripolyphosphate and the α-helix binding loss of BSA. TGA revealed an increase in the thermal stability of N-trimethyl chitosan/protein nanoparticles compared with the powder. The encapsulation of the cargo protein used was demonstrated using XPS. Their potential to improve cell permeability and use as nanocarriers in future vaccine formulations was demonstrated. The toxicity of the nanoparticles in HaCaT and J774 cells was studied, as well as the importance of evaluating the differentiation status of J774 cells. Thus, possible endocytosis pathways and their impact on the immune response were discussed. This allowed us to conclude that N-trimethyl chitosan nanoparticles show potential as carriers for the immune system. Still, more studies are required to understand their effectiveness and possible use in therapies.

Synthesis of BLF1-containing trimethyl chitosan nanoparticles and evaluation of its immunogenicity and protection in syrian mice by oral and subcutaneous injections

The bacterium Burkholderia pseudomallei is the cause of melioidosis infectious disease. In this bacterium, the BLF1 protein wide inhibits the synthesis of proteins in human cells. This disease is reported to cause a death rate of 40% in some parts of the world. Currently, no effective vaccine is available against this bacterial infection. In this study, therefore, a Nano vaccine was synthesized based on the trimethyl chitosan (TMC) polymer containing the BLF1 recombinant protein, and its immunogenicity and protection in Syrian mice were evaluated by oral and subcutaneous injections. The BLF1 recombinant protein expression was induced in Escherichia coli Bl21 (DE3) and purified by the affinity chromatography technique. Recombinant protein-containing nanoparticles (NPs) were then synthesized by the ionotropic gelation method. After oral and subcutaneous injections, antibody titration was assessed by the indirect ELISA assay. Finally, murine groups were challenged using the BLF1 toxin. The results indicated that the immune system showed more antibody titration in subcutaneous injection than in the oral form. However, the results were reversed in the challenge results, and the survival rate was more significant in the oral injection.

Chitosan Nanoparticles for Intranasal Drug Delivery

This manuscript explores the use of nanostructured chitosan for intranasal drug delivery, targeting improved therapeutic outcomes in neurodegenerative diseases, psychiatric care, pain management, vaccination, and diabetes treatment. Chitosan nanoparticles are shown to enhance brain delivery, improve bioavailability, and minimize systemic side effects by facilitating drug transport across the blood-brain barrier. Despite substantial advancements in targeted delivery and vaccine efficacy, challenges remain in scalability, regulatory approval, and transitioning from preclinical studies to clinical applications. The future of chitosan-based nanomedicines hinges on advancing clinical trials, fostering interdisciplinary collaboration, and innovating in nanoparticle design to overcome these hurdles and realize their therapeutic potential.

Recent Advances in Delivery of Peptide and Protein Therapeutics to the Brain

The classes of neuropharmaceuticals known as proteins and peptides serve as diagnostic tools and are involved in specific communication in the peripheral and central nervous systems. However, due to tight junctions resembling epithelial cells found in the blood-brain barrier (BBB) in vivo, they are typically excluded from transport from the blood to the brain. The drugs having molecular weight of less than 400 Dalton are able to cross the BBB via lipid-mediated free diffusion. However, large molecule therapeutics are devoid of these characteristics. As an alternative, these substances may be carried via chimeric peptide drug delivery systems, and assist in transcytosis through BBB with the aid of linker strategies. With their recent developments, several forms of nanoparticles, including poly (ethylene glycol)-poly(ε-caprolactone) copolymers, nanogels, liposomes, nanostructured lipid carriers, poly (D, L-lactide-co-glycolide) nanoparticles, chitosan, and solid lipid nanoparticles, have also been considered for their therapeutic applications. Moreover, the necessity for physiologic optimization of current drug delivery methods and their carriers to deliver therapeutic doses of medication into the brain for the treatment of various neurologic illnesses has also been emphasized. Therapeutic use of proteins and peptides has no neuroprotective impact in the absence of all these methods. Each tactic, however, has unique drawbacks and considerations. In this review, we discuss different drug delivery methods for therapeutic distribution of pharmaceuticals, primarily neuroproteins and neuropeptides, through endothelial capillaries via blood-brain barrier. Finally, we have also discussed the challenges and future perspective of protein and peptide therapeutics delivery to the brain. SIGNIFICANCE STATEMENT: Very few reports on the delivery of therapeutic protein and peptide nanoformulations are available in the literature. Herein, we attempted to discuss these nanoformulations of protein and peptide therapeutics used to treat brain diseases.

Optimization of ionizable lipids for aerosolizable mRNA lipid nanoparticles

Although mRNA lipid nanoparticles (LNPs) are highly effective as vaccines, their efficacy for pulmonary delivery has not yet fully been established. A major barrier to this therapeutic goal is their instability during aerosolization for local delivery. This imparts a shear force that degrades the mRNA cargo and therefore reduces cell transfection. In addition to remaining stable upon aerosolization, mRNA LNPs must also possess the aerodynamic properties to achieve deposition in clinically relevant areas of the lungs. We addressed these challenges by formulating mRNA LNPs with SM-102, the clinically approved ionizable lipid in the Spikevax COVID-19 vaccine. Our lead candidate, B-1, had the highest mRNA expression in both a physiologically relevant air-liquid interface (ALI) human lung cell model and in healthy mice lungs upon aerosolization. Further, B-1 showed selective transfection in vivo of lung epithelial cells compared to immune cells and endothelial cells. These results show that the formulation can target therapeutically relevant cells in pulmonary diseases such as cystic fibrosis. Morphological studies of B-1 revealed differences in the surface structure compared to LNPs with lower transfection efficiency. Importantly, the formulation maintained critical aerodynamic properties in simulated human airways upon next generation impaction. Finally, structure-function analysis of SM-102 revealed that small changes in the number of carbons can improve upon mRNA delivery in ALI human lung cells. Overall, our study expands the application of SM-102 and its analogs to aerosolized pulmonary delivery and identifies a potent lead candidate for future therapeutically active mRNA therapies.

Chitosan, Chitosan/IgG-Loaded, and N-Trimethyl Chitosan Chloride Nanoparticles as Potential Adjuvant and Carrier-Delivery Systems

This work proposes a feasible, reproducible, and low-cost modified method to manufacture chitosan, chitosan/IgG-protein-loaded, and trimethylated chitosan nanoparticles, using microfluidics combined with the microemulsion technique, which differs from the traditional batch process of chitosan-based nanoparticles. The synthesis process consists of generating microreactors of chitosan-based polymer in a poly-dimethylsiloxane ψ-shaped microfluidic device and then crosslinking with sodium tripolyphosphate outside the cell. Transmission electron microscopy demonstrates an improvement in size control and distribution of the solid-shape chitosan nanoparticles (~80 nm) compared to the batch synthesis. Regarding chitosan/IgG-protein-loaded nanoparticles, these presented a core-shell morphology having a diameter of close to 15 nm. Raman and X-ray photoelectron spectroscopies confirmed the ionic crosslinking between the amino groups of chitosan and the phosphate groups of sodium tripolyphosphate in the fabricated samples and the total encapsulation of IgG protein during the fabrication of chitosan/IgG-loaded nanoparticles. Then, an ionic crosslinking and nucleation-diffusion process of chitosan-sodium tripolyphosphate was carried out during the nanoparticle formation, with and without IgG protein loading. The use of N-trimethyl chloride chitosan nanoparticles in vitro on human-keratinocyte-derived cell line HaCaT did not show side effects independently of its concentration from 1 to 10 μg/mL. Therefore, the proposed materials could be used as potential carrier-delivery systems.

Intranasal spray of cubosomal Tizanidine Hydrochloride for brain targeting: In-vitro and in-vivo characterization

Tizanidine HCl (TH) is used as first-line therapy for the treatment of muscular spasm. The intranasal cubosomal delivery system of TH for site-specific delivery i.e. CNS was developed. Cubosomes of TH were prepared using Glyceryl monooleate (GMO) as a lipid, poloxamer 407 as stabilizer, and ethanol and polyethylene glycol 200 as co-solvent. Optimized cubosomes of TH were characterized for vesicle size, zeta potential, % drug entrapment, mucin binding efficiency, which found to be 50.22 nm, -6.39 mV, 69.28%, 42.12%. It is also evaluated for CRYO-FESEM, CRYO-TEM, SAXS, residual solvent content, and in-vitro drug release. Ex-vivo permeation was also conducted at 7.4 and it indicates that almost 93.66% drug was diffused from a formulation in 6 hrs. Histopathological study of the optimized TH cubosomes suggests that the prepared formulation is non-toxic to the nasal mucosa. Pharmacokinetic and brain distribution study indicates targeted action of the formulated TH cubosomes.

Recent advances in respiratory immunization: A focus on COVID-19 vaccines

The development of vaccines has always been an essential task worldwide since vaccines are regarded as powerful weapons in protecting the global population. Although the vast majority of currently authorized human vaccinations are administered intramuscularly or subcutaneously, exploring novel routes of immunization has been a prominent area of study in recent years. This is particularly relevant in the face of pandemic diseases, such as COVID-19, where respiratory immunization offers distinct advantages, such as inducing systemic and mucosal responses to prevent viral infections in both the upper and lower respiratory tracts and also leading to higher patient compliance. However, the development of respiratory vaccines confronts challenges due to the physiological barriers of the respiratory tract, with most of these vaccines still in the research and development stage. In this review, we detail the structure of the respiratory tract and the mechanisms of mucosal immunity, as well as the obstacles to respiratory vaccination. We also examine the considerations necessary in constructing a COVID-19 respiratory vaccine, including the dosage form of the vaccines, potential excipients and mucosal adjuvants, and delivery systems and devices for respiratory vaccines. Finally, we present a comprehensive overview of the COVID-19 respiratory vaccines currently under clinical investigation. We hope this review can provide valuable insights and inspiration for the future development of respiratory vaccinations.

Arginine-Coated Nanoglobules for the Nasal Delivery of Insulin

Multiple daily injections via subcutaneous route are the primary modes of insulin delivery for patients with Diabetes Mellitus. While this process is invasive, painful and may cause patients to develop lipohypertrophy at injection site, the perception of fear surrounding this process causes patients to delay in initiation and remain persistent with insulin therapy over time. Moreover, poor glycemic control may often lead to acute complications, such as severe hypoglycemia and nocturnal hypoglycemia, especially in older patients with diabetes. To address the imperative need for a patient-convenient non-invasive insulin therapy, an insulin-loaded arginine-coated self-emulsifying nanoglobule system (INS-LANano) was developed for nasal delivery of insulin with a biodegradable cationic surfactant-Lauroyl Ethyl Arginate (LAE). Incorporation of LAE resulted in formation of positively charged nanoglobules with L-arginine oriented on the surface. LANano enabled binding of insulin molecules on the surface of nanoglobules via an electrostatic interaction between negatively charged α-helix and LAE molecules at physiological pH. INS-LANano showed a hydrodynamic diameter of 23.38 nm with a surface charge of +0.118 mV. The binding efficiency of insulin on LANano globules was confirmed by zeta potential, circular dichroism (CD) spectroscopy and centrifugal ultrafiltration studies. The attachment of insulin with permeation-enhancing nanoglobules demonstrated significantly higher in vitro permeability of insulin of 15.2% compared to insulin solution across human airway epithelial cell (Calu-3) monolayer. Upon intranasal administration of INS-LANano to diabetic rats at 2 IU/kg insulin dose, a rapid absorption of insulin with significantly higher Cmax of 14.3 mU/L and relative bioavailability (BA) of 23.3% was observed. Therefore, the INS-LANano formulation significant translational potential for intranasal delivery of insulin.

Formulation Development of Fast Dissolving Microneedles Loaded with Cubosomes of Febuxostat: In Vitro and In Vivo Evaluation

Febuxostat is a widely prescribed drug for the treatment of gout, which is a highly prevalent disease worldwide and is a major cause of disability in mankind. Febuxostat suffers from several limitations such as gastrointestinal disturbances and low oral bioavailability. Thus, to improve patient compliance and bioavailability, transdermal drug delivery systems of Febuxostat were developed for obtaining enhanced permeation. Cubosomes of Febuxostat were prepared using a bottom-up approach and loaded into a microneedle using a micromolding technique to achieve better permeation through the skin. Optimization of the process and formulation parameters were achieved using our design of experiments. The optimized cubosomes of Febuxostat were characterized for various parameters such as % entrapment efficiency, vesicle size, Polydispersity index, Transmission electron microscopy, in vitro drug release, Small angle X-ray scattering, etc. After loading it in the microneedle it was characterized for dissolution time, axial fracture force, scanning electron microscopy, in vitro drug release, pore closure kinetics, etc. It was also evaluated for various ex vivo characterizations such as in vitro cell viability, ex vivo permeation, ex vivo fluorescence microscopy and histopathology which indicates its safety and better permeation. In vivo pharmacokinetic studies proved enhanced bioavailability compared with the marketed formulation. Pharmacodynamic study indicated its effectiveness in a disease-induced rat model. The developed formulations were then subjected to the stability study, which proved its stability.

Impact of Nanotechnology on Differentiation and Augmentation of Stem Cells for Liver Therapy

The liver is one of the crucial organs of the body that performs hundreds of chemical reactions needed by the body to survive. It is also the largest gland of the body. The liver has multiple functions, including the synthesis of chemicals, metabolism of nutrients, and removal of toxins. It also acts as a storage unit. The liver has a unique ability to regenerate itself, but it can lead to permanent damage if the injury is beyond recovery. The only possible treatment of severe liver damage is liver transplant which is a costly procedure and has several other drawbacks. Therefore, attention has been shifted towards the use of stem cells that have shown the ability to differentiate into hepatocytes. Among the numerous kinds of stem cells (SCs), the mesenchymal stem cells (MSCs) are the most famous. Various studies suggest that an MSC transplant can repair liver function, improve the signs and symptoms, and increase the chances of survival. This review discusses the impact of combining stem cell therapy with nanotechnology. By integrating stem cell science and nanotechnology, the information about stem cell differentiation and regulation will increase, resulting in a better comprehension of stem cell-based treatment strategies. The augmentation of SCs with nanoparticles has been shown to boost the effect of stem cell-based therapy. Also, the function of green nanoparticles in liver therapies is discussed.

Nanomaterials in tuberculosis DNA vaccine delivery: historical perspective and current landscape

Vaccinations, especially DNA vaccines that promote host immunity, are the most effective interventions for tuberculosis (TB) control. However, the vaccine delivery system exhibits a significant impact on the protective effects of the vaccine. Recently, effective nanomaterial-based delivery systems (including nanoparticles, nanogold, nanoliposomes, virus-like particles, and virus carriers) have been developed for DNA vaccines to control TB. This review highlights the historical development of various nanomaterial-based delivery systems for TB DNA vaccines, along with the emerging technologies. Nanomaterial-based vaccine delivery systems could enhance the efficacy of TB vaccination; therefore, this summary could guide nanomaterial selection for optimal and safe vaccine delivery, facilitating the design and development of highly effective TB vaccines.

Mucosal delivery of nanovaccine strategy against COVID-19 and its variants

Despite the global administration of approved COVID-19 vaccines (e.g., ChAdOx1 nCoV-19®, mRNA-1273®, BNT162b2®), the number of infections and fatalities continue to rise at an alarming rate because of the new variants such as Omicron and its subvariants. Including COVID-19 vaccines that are licensed for human use, most of the vaccines that are currently in clinical trials are administered via parenteral route. However, it has been proven that the parenteral vaccines do not induce localized immunity in the upper respiratory mucosal surface, and administration of the currently approved vaccines does not necessarily lead to sterilizing immunity. This further supports the necessity of a mucosal vaccine that blocks the main entrance route of COVID-19: nasal and oral mucosal surfaces. Understanding the mechanism of immune regulation of M cells and dendritic cells and targeting them can be another promising approach for the successful stimulation of the mucosal immune system. This paper reviews the basic mechanisms of the mucosal immunity elicited by mucosal vaccines and summarizes the practical aspects and challenges of nanotechnology-based vaccine platform development, as well as ligand hybrid nanoparticles as potentially effective target delivery agents for mucosal vaccines.

PA-X Protein of H1N1 Subtype Influenza Virus Disables the Nasal Mucosal Dendritic Cells for Strengthening Virulence

PA-X protein arises from a ribosomal frameshift in the PA of influenza A virus (IAV). However, the immune regulatory effect of the PA-X protein of H1N1 viruses on the nasal mucosal system remains unclear. Here, a PA-X deficient H1N1 rPR8 viral strain (rPR8-△PAX) was generated and its pathogenicity was determined. The results showed that PA-X was a pro-virulence factor in mice. Furthermore, it reduced the ability of H1N1 viruses to infect dendritic cells (DCs), the regulator of the mucosal immune system, but not non-immune cells (DF-1 and Calu-3). Following intranasal infection of mice, CCL20, a chemokine that monitors the recruitment of submucosal DCs, was downregulated by PA-X, resulting in an inhibition of the recruitment of CD11b+ DCs to submucosa. It also attenuated the migration of CCR7+ DCs to cervical lymph nodes and inhibited DC maturation with low MHC II and CD40 expression. Moreover, PA-X suppressed the maturation of phenotypic markers (CD80, CD86, CD40, and MHC II) and the levels of secreted pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) while enhancing endocytosis and levels of anti-inflammatory IL-10 in vitro, suggesting an impaired maturation of DCs that the key step for the activation of downstream immune responses. These findings suggested the PA-X protein played a critical role in escaping the immune response of nasal mucosal DCs for increasing the virulence of H1N1 viruses.

Polymeric Nanoparticles for Inhaled Vaccines

Many recent studies focus on the pulmonary delivery of vaccines as it is needle-free, safe, and effective. Inhaled vaccines enhance systemic and mucosal immunization but still faces many limitations that can be resolved using polymeric nanoparticles (PNPs). This review focuses on the use of properties of PNPs, specifically chitosan and PLGA to be used in the delivery of vaccines by inhalation. It also aims to highlight that PNPs have adjuvant properties by themselves that induce cellular and humeral immunogenicity. Further, different factors influence the behavior of PNP in vivo such as size, morphology, and charge are discussed. Finally, some of the primary challenges facing PNPs are reviewed including formulation instability, reproducibility, device-related factors, patient-related factors, and industrial-level scale-up. Herein, the most important variables of PNPs that shall be defined in any PNPs to be used for pulmonary delivery are defined. Further, this study focuses on the most popular polymers used for this purpose.

iRGD-grafted N-trimethyl chitosan-coated protein nanotubes enhanced the anticancer efficacy of curcumin and melittin

Curcumin (Cur) and Melittin (Mel) are two natural extracts that have been shown anti-tumor effects. However, their applications are limited due to poor oral bioavailability and the lack of tumor-targeting property. Here, we developed a novel nanocomposite that enabled the co-delivery of Cur and Mel, which consists of α-lactalbumin protein nanotubes (NTs), positively charged N,N,N-trimethyl chitosan (TMC), and a tumor-targeting cyclic peptide iRGD. The results showed that NTs/Cur-TMC-Mel-iRGD incorporated the advantages of each component, for instance, effective compounds loading by NTs, improved cellular uptake by TMC, prolonged accumulation in tumors by iRGD as well as synergistic anti-tumor effects of Cur and Mel. In the tumor-bearing mice, NTs/Cur-TMC-Mel-iRGD treatment remarkably induced cancer cell apoptosis while inhibiting cell proliferation, leading to suppressed tumor growth. Besides, no obvious adverse effects were observed in the blood physiology and tissue histology. Overall, our study provided an effective strategy for co-delivering Cur and Mel, which has a potential for translational clinical research aiming to treat solid tumors.

Preparation of Lambda-Cyhalothrin-Loaded Chitosan Nanoparticles and Their Bioactivity against Drosophila suzukii

The encapsulation of pesticides within nanoparticles is a promising approach of advanced technology in sustainable agriculture. Lambda-cyhalothrin (LC) was encapsulated by the ionotropic gelation technique into chitosan (CS)/tripolyphosphate (TPP) and CS/alginate (ALG) matrixes. CS-LC nanoparticles were characterized, and their efficacy was then evaluated against the key pest of soft fruits in Europe and the United States, Drosophila suzukii. The encapsulation efficiency (74%), nanoparticle yield (80%), polydispersity index (0.341), zeta potential (-23.1 mV) and particle size (278 nm) were determined at the optimum conditions. FTIR confirmed the cross-linkage between CS and TPP/ALG in the nanoparticles. The optimum formula recommended by the fractional factorial design was associated with the formulation variables of CS of high or low molecular weight, cross-linking agent (TPP), LC concentration (1.5% w/v) and stirring rate (1500 rpm), showing the highest desirability value (0.5511). CS-LC nanoparticles of the lowest particle size (278 nm) exhibited the highest percent mortality of D. suzukii males (86%) and females (84%), exceeding that caused by the commercial product (Karate-zeon^® 10% CS) at 2 HAT. This is the first work to use the ionic gelation technique to make LC nanoparticles, to the best of our knowledge. The encapsulation of chemical pesticides within biodegradable polymeric nanoparticles could be helpful for establishing a sustainable IPM strategy with benefits for human and environmental health and the lifetime of pesticides.

Evaluation of the self-assembled functional PPFS-P-AM composite for treating oilfield sewage

Oilfield sewage has a complex composition with large amounts of emulsified oils, polymers and surfactants. Efficient coagulants are required to purify such sewage to meet emissions standards. In this study, oxidized FeSO₄·7H₂O and NaHCO₃were condensed by basic titration and polyferric sulfate phosphate (PPFS) was prepared by the addition of NaH₂PO₄·2H₂O to improve its charge and stability. In addition, by adding modified palygorskite and cationic amylum, a functional polyferric sulfate phosphate, palygorskite and cationic amylum copolymer (PPFS-P-AM) composite coagulant was synthesized through self-assembly, and then used to treat oilfield sewage. The characteristic functional groups and crystal forms of the coagulant were characterized by FTIR and XRD. The zeta potential and radius of gyration (R_h) indicate that the introduction of palygorskite and cationic amylum enhance the charge neutralization and bridging adsorption abilities, respectively. The optimal dosage of cationic amylum is 5% in 80 mg·L^-1 PPFS-P-AM, which provides turbidity and oil removal rates of 98% and 94%, respectively. Observation by SEM shows that the micro-morphology of PPFS-P-AM flocs has adendritic distribution with a reticular macromolecular structure that provides good sweeping performance during the sedimentation process. Finally, an analysis of its properties and performance reveals the mechanism by which PPFS-P-AM coagulates oilfield sewage. PPFS-P-AM provides better coagulation than the other studied coagulants via the synergistic effects of reinforced charge neutralization, bridging adsorption and sweeping.

The Potential of Chitosan in Nanomedicine: An Overview of the Cytotoxicity of Chitosan Based Nanoparticles

The unique properties and applications of nanotechnology in targeting drug delivery, cosmetics, fabrics, water treatment and food packaging have received increased focus the last two decades. The application of nanoparticles in medicine is rapidly evolving, requiring careful investigation of toxicity before clinical use. Chitosan, a derivative of the natural polysaccharide chitin, has become increasingly relevant in modern medicine because of its unique properties as a nanoparticle. Chitosan is already widely used as a food additive and in food packaging, bandages and wound dressings. Thus, with an increasing application worldwide, cytotoxicity assessment of nanoparticles prepared from chitosan is of great interest. The purpose of this review is to provide an updated status of cytotoxicity studies scrutinizing the safety of chitosan nanoparticles used in biomedical research. A search in Ovid Medline from 23 March 1998 to 4 January 2022, with the combination of the search words Chitosan or chitosan, nanoparticle or nano particle or nanosphere or nanocapsule or nano capsule, toxicology or toxic or cytotoxic and mucosa or mucous membrane resulted in a total of 88 articles. After reviewing all the articles, those involving non-organic nanoparticles and cytotoxicity assays conducted exclusively on nanoparticles with anti-tumor effect (i.e., having cytotoxic effect) were excluded, resulting in 70 articles. Overall, the chitosan nanoparticles included in this review seem to express low cytotoxicity regardless of particle composition or cytotoxicity assay and cell line used for testing. Nonetheless, all new chitosan derivatives and compositions are recommended to undergo careful characterization and cytotoxicity assessment before being implemented on the market.

Bee venom-loaded EGFR-targeting peptide-coupled chitosan nanoparticles for effective therapy of hepatocellular carcinoma by inhibiting EGFR-mediated MEK/ERK pathway

Hepatocellular carcinoma (HCC) is one of the world's most risky diseases due to the lack of clear and cost-effective therapeutic targets. Currently, the toxicity of conventional chemotherapeutic medications and the development of multidrug resistance is driving research into targeted therapies. The nano-biomedical field's potential for developing an effective therapeutic nano-sized drug delivery system is viewed as a significant pharmaceutical trend for the encapsulation and release of numerous anticancer therapies. In this regard, current research is centered on the creation of biodegradable chitosan nanoparticles (CSNPs) for the selective and sustained release of bee venom into liver cancer cells. Furthermore, surface modification with polyethylene glycol (PEG) and GE11 peptide-conjugated bee venom-CSNPs allows for the targeting of EGFR-overexpressed liver cancer cells. A series of in vitro and in vivo cellular analyses were used to investigate the antitumor effects and mechanisms of targeted bee venom-CSNPs. Targeted bee venom-CSNPs, in particular, were found to have higher cytotoxicity against HepG2 cells than SMMC-7721 cells, as well as stronger cellular uptake and a substantial reduction in cell migration, leading to improved cancer suppression. It also promotes cancer cell death in EGFR overexpressed HepG2 cells by boosting reactive oxygen species, activating mitochondria-dependent pathways, inhibiting EGFR-stimulated MEK/ERK pathway, and elevating p38-MAPK in comparison to native bee venom. In hepatocellular carcinoma (HCC)-induced mice, it has anti-cancer properties against tumor tissue. It also improved liver function and architecture without causing any noticeable toxic side effects, as well as inhibiting tumor growth by activating the apoptotic pathway. The design of this cancer-targeted nanoparticle establishes GE11-bee venom-CSNPs as a potential chemotherapeutic treatment for EGFR over-expressed malignancies. Finally, our work elucidates the molecular mechanism underlying the anticancer selectivity of targeted bee venom-CSNPs and outlines therapeutic strategies to target liver cancer.

Immunological Assessment of Chitosan or Trimethyl Chitosan-Coated PLGA Nanospheres Containing Fusion Antigen as the Novel Vaccine Candidates Against Tuberculosis

The crucial challenge in tuberculosis (TB) as a chronic infectious disease is to present a novel vaccine candidate that improves current vaccination and provides efficient protection in individuals. The present study aimed to evaluate the immune efficacy of multi-subunit vaccines containing chitosan (CHT)- or trimethyl chitosan (TMC)-coated PLGA nanospheres to stimulate cell-mediated and mucosal responses against Mycobacterium Tuberculosis (Mtb) in an animal model. The surface-modified PLGA nanoparticles (NPs) containing tri-fusion protein from three Mtb antigens were produced by the double emulsion technique. The subcutaneously or nasally administered PLGA vaccines in the absence or presence of BCG were assessed to compare the levels of mucosal IgA, IgG1, and IgG2a production as well as secretion of IFN-γ, IL-17, IL-4, and TGF-β cytokines. According to the release profile, the tri-fusion encapsulated in modified PLGA NPs demonstrated a biphasic release profile including initial burst release on the first day and sustained release within 18 days. All designed PLGA vaccines induced a shift of Th1/Th2 balance toward Th1-dominant response. Although immunized mice through subcutaneous injection elicited higher cell-mediated responses relative to the nasal vaccination, the intranasally administered groups stimulated robust mucosal IgA immunity. The modified PLGA NPs using TMC cationic polymer were more efficient to elevate Th1 and mucosal responses in comparison with the CHT-coated PLGA nanospheres. Our findings highlighted that the tri-fusion loaded in TMC-PLGA NPs may represent an efficient prophylactic vaccine and can be considered as a novel candidate against TB.

N-trimethyl chitosan coated nano-complexes enhance the oral bioavailability and chemotherapeutic effects of gemcitabine

N-trimethyl chitosan (TMC) is a multifunctional polymer that can be used in various nanoparticle forms in the pharmaceutical, nutraceutical and biomedical fields. In this study, TMC was used as a mucoadhesive adjuvant to enhance the oral bioavailability and hence antitumour effects of gemcitabine formulated into nanocomplexes composed of poly(lactic-co-glycolic acid) nanoparticles (PLGA NPs) conjugated with d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS). A central composite design was applied to achieve the optimal formulation. Cellular uptake and drug transportation studies revealed the nanocomplexes permeate over the intestinal cells via adsorptive-mediated and caveolae-mediated endocytosis. Pharmacokinetic studies demonstrated the oral drug bioavailability of the nanocomplexes was increased 5.1-fold compared with drug solution. In pharmacodynamic studies, the formulation reduced tumour size 3.1-fold compared with the drug solution. The data demonstrates that TMC modified nanocomplexes can enhance gemcitabine oral bioavailability and promote the anticancer efficacy.

Design of a chitosan-based nano vaccine against epsilon toxin of Clostridium perfringens type D and evaluation of its immunogenicity in BALB/c mice

Background and purpose

Clostridium perfringens is an anaerobic, spore-forming, and pathogenic bacterium that causes intestinal diseases in humans and animals. In these cases, therapeutic intervention is challenging; because the disease progresses much rapidly. This bacterium can produce 5 main toxins (alpha, beta, epsilon, iota, and a type of enterotoxin) among which the epsilon toxin (ETX) is used for bioterrorism. This toxin can be prevented by immunization with specific immunogenic vaccines. In the present research, we aimed at developing a recombinant chitosan-based nano-vaccine against ETX of C. perfringens and evaluate its effects on the antibody titration against epsilon toxin in BALB/c mice as the vaccine model.

Experimental approach

The etx gene from C. perfringens type D was cloned and expressed in E. coli. After analysis by SDS-PAGE and western blotting, the expressed products were purified, and the obtained proteins were used for immunization in mice as a chitosan nanoparticle containing recombinant, purified ETX, and protein.

Findings/Results

The results of ELISA showed that IgA antibody serum level increased sufficiently using recombinant protein with nanoparticle as an oral and injectable formulation. IgG antibody titers increased significantly after administrating the recombinant proteins with nanoparticles through both oral delivery and intravenous injection.

Conclusion and implication

In conclusion, the recombinant ETX is suggested as a good candidate for vaccine production against diseases caused by ETX of C. perfringens type D.

Preparation of Chitosan Nanoparticles as a Capable Carrier for Antigen Delivery and Antibody Production

Background

Chitosan (CS) nanoparticles have attracted considerable attention as a non-viral and cationic carrier for delivery of therapeutic proteins and antigens and offer non-invasive routes of administration such as oral, nasal and ocular routes, and also show adjuvant characteristics for vaccines.

Objectives

Preparation and formulation of CS nanoparticles as a capable carrier with immunoadjuvant properties to enhance the bioavailability of antigen and produce antibody with high affinity.

Materials and Methods

CS nanoparticles were produced by ionic gelation process of sodium tripolyphosphate (TPP) with CS. Particle size and morphology of nanoparticles were determined using Dynamic Light Scattering (DLS) and Scanning Electron Microscopy (SEM) and also direct observation under light microscope. The influence of the initial BSA concentration and CS concentration on loading efficiency and release behavior was evaluated. The ε-toxin (derived from Clostridium perfringens type D) was loaded on CS nanoparticles and the complex was injected hypodermically into the rabbits for once. The anti ε-toxin antibody level in blood serum was evaluated using Dot Blot and ELISA methods.

Results

The CS nanoparticles in different groups have a particle diameter (Z-average) in approximate ranges of 200-400, 300-600, 450-800 nm and a positive Zeta potential (32.4 - 48.6 mv). Optimum loading efficiency was achieved for CS at a concentration of 0.5 mg.mL^-1 and TPP of 1.0 mg.mL^-1. The results showed that the toxin-CS complex produces antitoxin at levels more than twice as high the control.

Conclusion

The CS nanoparticles can be used as a good biodegradable carrier for protein and antigen delivery.

Nanotechnologies for the delivery of biologicals: Historical perspective and current landscape

Biological macromolecule-based therapeutics irrupted in the pharmaceutical scene generating a great hope due to their outstanding specificity and potency. However, given their susceptibility to degradation and limited capacity to overcome biological barriers new delivery technologies had to be developed for them to reach their targets. This review aims at analyzing the historical seminal advances that shaped the development of the protein/peptide delivery field, along with the emerging technologies on the lead of the current landscape. Particularly, focus is made on technologies with a potential for transmucosal systemic delivery of protein/peptide drugs, followed by approaches for the delivery of antigens as new vaccination strategies, and formulations of biological drugs in oncology, with special emphasis on mAbs. Finally, a discussion of the key challenges the field is facing, along with an overview of prospective advances are provided.

Self-assembled chitosan nanoparticles for intranasal delivery of recombinant protein interleukin-17 receptor C (IL-17RC): preparation and evaluation in asthma mice

Asthma is mentioned as a chronic airway inflammatory disease, whose pathogenesis is complicated. The promotion of inflammation in asthma by IL-17A and IL-17F has been confirmed. In addition to covalent homodimers, both cytokines are also able to form heterodimers, further inducing downstream pathways via binding to the IL-17RA and IL-17RC receptor complex. In recent years, IL-17RA and its signal transduction pathway have been extensively researched. IL-17RC, however, remains relatively unexplored. In the present study, we self-assembled chitosan (CS) nanoparticles for intranasal delivery of recombinant protein IL-17RC (rIL-17RC) and preliminarily investigated its effect on a murine model of allergic asthma induced by ovalbumin (OVA). rIL-17RC was produced by the prokaryotic expression system and encapsulated into the CS nanoparticles via ionic cross-linking technique. The results showed that CS-RC nanoparticles via intranasal intervention significantly caused inhibition of mucus secretion and airway inflammatory cell infiltration, and reduced IL-4, IL-17, IL-17F levels in BALF. Hence, delivering receptor proteins such as IL-17RC, through CS nanoparticles as a carrier, could be an attractive therapeutic intervention for asthma.

The impact of chemical engineering and technological advances on managing diabetes: present and future concepts

Monitoring blood glucose levels for diabetic patients is critical to achieve tight glycaemic control. As none of the current antidiabetic treatments restore lost functional β-cell mass in diabetic patients, insulin injections and the use of insulin pumps are most widely used in the management of glycaemia. The use of advanced and intelligent chemical engineering, together with the incorporation of micro- and nanotechnological-based processes have lately revolutionized diabetic management. The start of this concept goes back to 1974 with the description of an electrode that repeatedly measures the level of blood glucose and triggers insulin release from an infusion pump to enter the blood stream from a small reservoir upon need. Next to the insulin pumps, other drug delivery routes, including nasal, transdermal and buccal, are currently investigated. These processes necessitate competences from chemists, engineers-alike and innovative views of pharmacologists and diabetologists. Engineered micro and nanostructures hold a unique potential when it comes to drug delivery applications required for the treatment of diabetic patients. As the technical aspects of chemistry, biology and informatics on medicine are expanding fast, time has come to step back and to evaluate the impact of technology-driven chemistry on diabetics and how the bridges from research laboratories to market products are established. In this review, the large variety of therapeutic approaches proposed in the last five years for diabetic patients are discussed in an applied context. A survey of the state of the art of closed-loop insulin delivery strategies in response to blood glucose level fluctuation is provided together with insights into the emerging key technologies for diagnosis and drug development. Chemical engineering strategies centered on preserving and regenerating functional pancreatic β-cell mass are evoked in addition as they represent a permanent solution for diabetic patients.

Surface Functionalization of PLGA Nanoparticles to Increase Transport across the BBB for Alzheimer’s Disease

Alzheimer’s disease (AD) is a chronic neurodegenerative disorder that accounts for about 60% of all diagnosed cases of dementia worldwide. Although there are currently several drugs marketed for its treatment, none are capable of slowing down or stopping the progression of AD. The role of the blood-brain barrier (BBB) plays a key role in the design of a successful treatment for this neurodegenerative disease. Nanosized particles have been proposed as suitable drug delivery systems to overcome BBB with the purpose of increasing bioavailability of drugs in the brain. Biodegradable poly (lactic-co-glycolic acid) nanoparticles (PLGA-NPs) have been particularly regarded as promising drug delivery systems as they can be surface-tailored with functionalized molecules for site-specific targeting. In this review, a thorough discussion about the most recent functionalization strategies based on PLGA-NPs for AD and their mechanisms of action is provided, together with a description of AD pathogenesis and the role of the BBB in brain targeting.

Low-dose paclitaxel via hyaluronan-functionalized bovine serum albumin nanoparticulate assembly for metastatic melanoma treatment

Due to the critical role of CD44 in mediating cell adhesion and migration, CD44-targeted drug delivery via hyaluronan has been extensively explored. Herein, cationic bovine serum albumin nanoparticles were assembled with hyaluronan (HA) of various molecular weights via simple electrostatic interaction to afford hierarchical nanoparticles (HNPs) with various size distributions and structures. Next, HNPs obtained using 49 kDa HA have been used to encapsulate paclitaxel (PTX-HNPs), which demonstrated selective lung accumulation due to both size effect and CD44-mediated targetability. Biodistribution studies showed that HNPs enhanced the lung specific accumulation of HNPs in the C57BL/6 mice melanoma lung metastasis model. In the antitumor studies, compared with the Taxol or bovine serum albumin nanoparticle (NP) groups, PTX-HNPs significantly inhibited B16F10 lung metastasis at a relatively low dose. Additionally, cell migration and invasion experiments in vitro further confirmed that PTX-HNPs significantly inhibited the migration of B16F10 cells compared to Taxol or paclitaxel-loaded NP groups. Overall, our results suggest that PTX-HNPs represent a highly promising strategy for the treatment of lung metastatic melanoma.

Nanogels Capable of Triggered Release

This chapter provides an overview of soft and environmentally sensitive polymeric nanosystems, which are widely known as nanogels. These particles keep great promise to the area of drug delivery due to their high biocompatibility with body fluids and tissues, as well as due to their ability to encapsulate and release the loaded drugs in a controlled manner. For a long period of time, the controlled drug delivery systems were designed to provide long-termed or sustained release. However, some medical treatments such as cancer chemotherapy, protein and gene delivery do not require the prolonged release of the drug in the site of action. In contrast, the rapid increase of the drug concentration is needed for gaining the desired biological effect. Being very sensitive to surrounding media and different stimuli, nanogels can undergo physico-chemical transitions or chemical changes in their structure. Such changes can result in more rapid release of the drugs, which is usually referred to as triggered drug release. Herein we give the basic information on nanogel unique features, methods of sensitive nanogels preparation, as well as on main mechanisms of triggered release. Additionally, the triggered release of low-molecular drugs and biomacromolecules are discussed.

Efficiency of GnRH-Loaded Chitosan Nanoparticles for Inducing LH Secretion and Fertile Ovulations in Protocols for Artificial Insemination in Rabbit Does

Simple Summary

Nano-drug delivery systems can be employed for improving ovulation induction prior to artificial insemination (AI) in rabbits. In this study, different routes of administration and different doses of GnRH–loaded chitosan nanoparticles (GnRH–ChNPs) were assessed for inducing ovulation in rabbits, proving their usefulness to reduce the GnRH dose and animal handling and improving AI outcomes. The use of GnRH–ChNPs allows for the reduction of the conventional intramuscular GnRH dose to half without compromising fertility. However, the addition of GnRH–ChNPs to semen extenders, although successfully inducing ovulation, has negative impacts on fertility. Thus, more studies are needed to allow further adjustments.

Abstract

Gonadotropin-releasing hormone (GnRH)–loaded chitosan nanoparticles (GnRH–ChNPs) were used at different doses and routes of administration to induce ovulation in rabbits as an attempt to improve artificial insemination (AI) procedures and outcomes. In this study, the characteristics (size, polydispersity, loading efficiency, and zeta-potential) of GnRH–ChNPs and the GnRH release pattern were determined in an in vitro study. A first in vivo study assessed the pituitary and ovarian response to different GnRH–ChNPs doses and routes of administration (two i.m. doses, Group HM = 0.4 µg and Group QM = 0.2 µg, and two intravaginal doses, Group HV = 4 µg and Group QV = 2 µg) against a control group (C) receiving bare GnRH (0.8 µg). The HM, QM, and HV treatments induced an earlier LH-surge (90 min) than that observed in group C (120 min), whilst the QV treatment failed to induce such LH surge. The number of ovulation points was similar among treatments, except for the QV treatment (no ovulation points). A second in vivo study was consequently developed to determine the hormonal (progesterone, P₄, and estradiol, E₂) profile and pregnancy outcomes of both HM and HV treatments against group C. The treatment HM, but not the treatment HV, showed adequate P₄ and E₂ concentrations, conception and parturition rates, litter size, litter weight, and viability rate at birth. Overall, the use of GnRH–ChNPs allows for a reduction in the conventional intramuscular GnRH dose to half without compromising fertility. However, the addition of GnRH–ChNPs to semen extenders, although successfully inducing ovulation, has negative impacts on fertility. Thus, more studies are needed to explore this point and allow further adjustments.

Molecular and cellular cues governing nanomaterial-mucosae interactions: from nanomedicine to nanotoxicology

Mucosal tissues constitute the largest interface between the body and the surrounding environment and they regulate the access of molecules, supramolecular structures, particulate matter, and pathogens into it. All mucosae are characterized by an outer mucus layer that protects the underlying cells from physicochemical, biological and mechanical insults, a mono-layered or stratified epithelium that forms tight junctions and controls the selective transport of solutes across it and associated lymphoid tissues that play a sentinel role. Mucus is a gel-like material comprised mainly of the glycoprotein mucin and water and it displays both hydrophilic and hydrophobic domains, a net negative charge, and high porosity and pore interconnectivity, providing an efficient barrier for the absorption of therapeutic agents. To prolong the residence time, absorption and bioavailability of a broad spectrum of active compounds upon mucosal administration, mucus-penetrating and mucoadhesive particles have been designed by tuning the chemical composition, the size, the density, and the surface properties. The benefits of utilizing nanomaterials that interact intimately with mucosae by different mechanisms in the nanomedicine field have been extensively reported. To ensure the safety of these nanosystems, their compatibility is evaluated in vitro and in vivo in preclinical and clinical trials. Conversely, there is a growing concern about the toxicity of nanomaterials dispersed in air and water effluents that unintentionally come into contact with the airways and the gastrointestinal tract. Thus, deep understanding of the key nanomaterial properties that govern the interplay with mucus and tissues is crucial for the rational design of more efficient drug delivery nanosystems (nanomedicine) and to anticipate the fate and side-effects of nanoparticulate matter upon acute or chronic exposure (nanotoxicology). This review initially overviews the complex structural features of mucosal tissues, including the structure of mucus, the epithelial barrier, the mucosal-associated lymphatic tissues and microbiota. Then, the most relevant investigations attempting to identify and validate the key particle features that govern nanomaterial-mucosa interactions and that are relevant in both nanomedicine and nanotoxicology are discussed in a holistic manner. Finally, the most popular experimental techniques and the incipient use of mathematical and computational models to characterize these interactions are described.

The dry powder formulation of mixed cross-linked dextran microspheres and tetanus toxoid-loaded trimethyl chitosan nanospheres as a potent adjuvant for nasal delivery system

OBJECTIVES

The present study aimed to determine the immunoadjuvant efficacy of mixed cross-linked dextran microspheres (CDM) and tetanus toxoid (TT)-loaded trimethyl chitosan (TMC) nanospheres in dry powder form.

MATERIALS AND METHODS

The TMC nanoparticles (NPs) containing TT were produced using the ionic gelation method. Co-administration of TT-loaded TMC NPs and CDM as an absorption enhancer was performed to improve immunity against the antigen. Dry powder formulations were delivered via the nasal route in a rabbit model.

RESULTS

Among immunization groups, mixing of CDM with TT encapsulated in TMC NPs could elicit the highest titer of systemic IgG antibody. Furthermore, the addition of CDM to TT-loaded TMC enhanced the sIgA response relative to the TT solution.

CONCLUSION

The TMC NPs had a considerable effect on mucosal and systemic immunity against the TT antigen. Therefore, the CDM excipient can be utilized for nasal immunization to elevate systemic and mucosal responses.

Influence of pH-responsive compounds synthesized from chitosan and hyaluronic acid on dual-responsive (pH/temperature) hydrogel drug delivery systems of Cortex Moutan

The polysaccharide-based pH-responsive compounds, namely, N,N,N-trimethyl chitosan (TMC), polyethylene glycolated hyaluronic acid (PEG-HA), and polysaccharide-based nano-conjugate of hyaluronic acid, chitosan oligosaccharide and alanine [HA-Ala-Chito(oligo)] were chemically synthesized using biopolymers chitosan and hyaluronic acid, and applied here to observe the changes in morphology, pH-stability, mechanical and drug-release behavior, and cytotoxicity of thermo-responsive polymer: Poloxamer 407 (PF127)-based drug delivery systems for traditional Chinese medicine Cortex Moutan (CM). The thermo-responsive hydrogel of PF127 loaded with CM (Gel^C) was used as control. The dual-responsive (pH/temperature) hydrogels: PF127/TMC/PEG-HA (Gel¹) and PF127/HA-Ala-Chito(oligo) (Gel²) showed improved mechanical behavior as obtained by rheology and mechanical agitation study, and pH-stability under various external pH conditions, and those improvements occurred due to the addition of polysaccharide-based pH-responsive compounds in the systems. Both, Gel¹ and Gel² showed better morphology than Gel^C as obtained by SEM or TEM suggesting that interaction of polysaccharide-based pH-responsive compounds with PF127 in either gel or sol state gave better porous network structure in the hydrogels or more dispersed micellar arrangements in sol-state, respectively. Gel¹ showed the highest cumulative drug release (86.5%) after 5 days under mild acidic condition (pH 6.4) suggesting that release behavior of a hydrogel drug carrier was dependent on morphology, mechanical behavior, and pH-stability. The transdermal release (ex-vivo) results indicated that gallic acid, the active marker of CM passed through porcine ear skin and all the formulations showed more or less similar transdermal release properties. The hydrogels loaded with CM showed no cytotoxicity (cell viability >90.0%) on human HaCaT keratinocytes within concentration range of 0.0-20.0 μg/ml as obtained by MTT assay, and cell viability was more than 100% at a concentration of 20.0 μg/ml for Gel². The formulations without loaded drug namely, Gel¹-CM and Gel²-CM exhibited strong anti-bacterial action against gram positive bacteria Staphylococcus aureus.

Development of an adjuvanted nanoparticle vaccine against influenza virus, an in vitro study

Influenza is an infectious respiratory illness caused by influenza viruses. Despite yearly updates, the efficacy of influenza vaccines is significantly curtailed by the virus antigenic drift and antigenic shift. These constant changes to the influenza virus make-up also challenge the development of a universal flu vaccine, which requires conserved antigenic regions shared by influenza viruses of different subtypes. We propose that it is possible to bypass these challenges by the development of an influenza vaccine based on conserved proteins delivered in an adjuvanted nanoparticle system. In this study, we generated influenza nanoparticle constructs using trimethyl chitosan nanoparticles (TMC nPs) as the carrier of recombinant influenza hemagglutinin subunit 2 (HA2) and nucleoprotein (NP). The purified HA2 and NP recombinant proteins were encapsulated into TMC nPs to form HA2-TMC nPs and NP-TMC nPs, respectively. Primary human intranasal epithelium cells (HNEpCs) were used as an in vitro model to measure immunity responses. HA2-TMC nPs, NP-TMC nPs, and HA2-NP-TMC nPs (influenza nanoparticle constructs) showed no toxicity in HNEpCs. The loading efficiency of HA2 and NP into the TMC nPs was 97.9% and 98.5%, respectively. HA2-TMC nPs and NP-TMC nPs more efficiently delivered HA2 and NP proteins to HNEpCs than soluble HA2 and NP proteins alone. The induction of various cytokines and chemokines was more evident in influenza nanoparticle construct-treated HNEpCs than in soluble protein-treated HNEpCs. In addition, soluble factors secreted by influenza nanoparticle construct-treated HNEpCs significantly induced MoDCs maturation markers (CD80, CD83, CD86 and HLA-DR), as compared to soluble factors secreted by protein-treated HNEpCs. HNEpCs treated with the influenza nanoparticle constructs significantly reduced influenza virus replication in an in vitro challenge assay. The results indicate that TMC nPs can be used as influenza vaccine adjuvants and carriers capable of delivering HA2 and NP proteins to HNEpCs.

Effectual Anticancer Potentiality of Loaded Bee Venom onto Fungal Chitosan Nanoparticles

Chitosan and its nanoparticles (NPs) could be extracted from numerous fungal species and used as effectual carriers for bioactive compounds. The fungal chitosan (FC) was innovatively acquired from Fusarium oxysporum grown mycelia, characterized and used for NP synthesis and loading with bee venom (BV). The nano-FC (NFC) had 192.4 nm mean NP diameter, 38.22% loading capacity, and 92.42% entrapment efficiency. BV release from NFC was pH and time dependent; burst BV release was detected at the first 6 h, followed by gradual releases up to 30 h. The in vitro anticancer potentiality valuation, of NFC, BV, and NFC/BV nanoconjugates against HeLa cervix carcinoma, revealed that they all had potent dose-dependent anticancer activity; BV/NFC nanoconjugates were the most effective with IC50=200 μg/mL. The fluorescent staining of treated HeLa cells with BV/NFC nanoconjugates, with DAPI and acridine orange/propidium iodide combination, indicated the appearance of early apoptosis, secondary apoptosis, and secondary necrosis markers and their increment with exposure prolongation. The production of NFC from F. oxysporum and their loading with BV are strongly counseled for production of potent natural antitumor agent with augmented activity against cervix carcinoma.

Characterisation of 2-HP-β-cyclodextrin-PLGA nanoparticle complexes for potential use as ocular drug delivery vehicles

Aim: 2-HP-β-cyclodextrin-PLGA nanoparticle complexes were prepared to enhance the aqueous humour delivery of Triamcinolone acetonide.Materials & methods: Drug-loaded 2-HP-β-CD/PLGA nanoparticle complexes prepared by adapting a quasi-emulsion solvent evaporation technique. In vitro drug release, in vitro transcorneal permeation study, histopathological study and in vivo transcorneal penetration of PLGA nanoparticles and 2-HP-β-CD/PLGA nanoparticle complexes were evaluated. Results: Particle size distributions of 2-HP-β-CD/PLGA nanoparticle complexes were 149.4 ± 3.7 nm and presented stable system. Corneal penetration studies revealed steady sustained drug release (First-order); 2-HP-β-CD/PLGA nanoparticle complexes increased ocular bioavailability by increasing dispersion in the tear film and improving drug release. Conclusion: 2-HP-β-CD/PLGA nanoparticle complex formulation is a promising alternative to conventional eye drops.

Para-sulfonatocalix[n]arene-based biomaterials: Recent progress in pharmaceutical and biological applications

The history, properties, and characteristics of para-sulfonato-calixarenes are described. On the one hand, the inherent antibacterial and antifungal properties against microorganisms, and on the other hand non-toxicity of these supramolecules toward human organs are analyzed. The resulting biocompatibility of para-sulfonato-calixarenes makes them potential candidates for diverse life sciences and pharmaceutical applications without significant side effects. The interactions with different drugs, the capability of drug encapsulation, delivery, and release, the formation of host-quest assemblies and inclusion complexation between para-sulfonato-calixarenes and drugs were also investigated in detail. Besides, their function in cancer treatment and their toxicity against different cancer cell lines were fully reviewed and summarized. Afterward, the capability of these macrocyclic compounds for biosensing of organic compounds, peptides and enzymes activity was highlighted. In this review, we also take a brief look at recent reports on the applications of para-sulfonato-calixarenes in fluorescence imaging and their usage as highly stable and bright probes for in vivo and in vitro imaging and sensing.

Designation of chitosan nano-vaccine based on MxiH antigen of Shigella flexneri with increased immunization capacity

Shigella flexneri is a gram-negative pathogen that causes shigellosis in humans and primates. MxiH antigen is known as one of the invasive factors in most Gram-negative bacteria consisting of a needle-like structure in the main backbone of the type 3 secretory system. Recombinant MxiH antigen was produced by E. coli BL21 and purified antigen was loaded into chitosan nanoparticles (CS-MxiH). After 20^thand 55^th of intranasal vaccinations, the titers of IgG, IgA, IL-4, and IFN-γ were evaluated. The results indicated the successful synthesis of CS nanoparticles followed by the effective loading of MxiH antigen. The results of animal experiments showed that the intranasal administration of CS-MxiH increased IgG and IgA compared to control groups. Increased levels of IL-4 and IFN-γ in groups immunized with CS-MxiH are probably due to the activation of plasmacytoid and myeloid cells presenting antigen in nasal epithelial mucosa and stimulating B cells.

Intranasal Nanoparticulate Systems as Alternative Route of Drug Delivery

There is always a need for alternative and efficient methods of drug delivery. The nasal cavity can be considered as a non-invasive and efficient route of administration. It has been used for local, systemic, brain targeting, and vaccination delivery. Although many intranasal products are currently available on the market, the majority is used for local delivery with fewer products available for the other targets. As nanotechnology utilization in drug delivery has rapidly spread out, the nasal delivery has become attractive as a promising approach. Nanoparticulate systems facilitate drug transportation across the mucosal barrier, protect the drug from nasal enzyme degradation, enhance the delivery of vaccines to the lymphoid tissue of the nasal cavity with an adjuvant activity, and offer a way for peptide delivery into the brain and the systemic circulation, in addition to their potential for brain tumor treatment. This review article aims at discussing the potential benefit of the intranasal nanoparticulate systems, including nanosuspensions, lipid and surfactant, and polymer-based nanoparticles as regards productive intranasal delivery. The aim of this review is to focus on the topicalities of nanotechnology applications for intranasal delivery of local, systemic, brain, and vaccination purposes during the last decade, referring to the factors affecting delivery, regulatory aspects, and patient expectations. This review further identifies the benefits of applying the Quality by Design approaches (QbD) in product development. According to the reported studies on nanotechnology-based intranasal delivery, potential attention has been focused on brain targeting and vaccine delivery with promising outcomes. Despite the significant research effort in this field, nanoparticle-based products for intranasal delivery are not available. Thus, further efforts are required to promote the introduction of intranasal nanoparticulate products that can meet the requirements of regulatory affairs with high patient acceptance.

In-vitro Detection of Phytopathogenic Fungal Cell Wall by Polyclonal Sera Raised Against Trimethyl Chitosan Nanoparticles

Purpose

The objective of this research was to generate a tool for the first-line detection of fungal infection in plants. Chitin is one of the unique fungal cell wall polysaccharide which is naturally deacetylated to chitosan upon infection. It is said to be involved in the fungal cell wall modulation and plant-pathogen communication. Therefore, detection of chitosan could be potentially helpful in the detection of fungal contamination.

Methods

Five different phytopathogenic fungi strains were used for the study. Polyclonal sera were raised in the mice against Trimethylchitosan nanoparticles to generate an enhanced humoral immune response and generate a rich and heterogeneous repertoire of antibodies. The binding affinity of the sera with fungal cell wall was analyzed by ELISA, Langmuir isotherm, confocal microscopy and ITC (Isothermal Calorimetry).

Results

The raised polyclonal sera could detect chitosan in the fungal cell wall, as analyzed with the different techniques. However, the detection specificity varied among the strains in proportion to the chitin content of their cell wall. Fusarium oxysporum was detected with the highest affinity while Trichoderma reesei was detected with the least affinity by ELISA. Adsorption isotherm, as well as ITC, revealed the specific and high binding capacity. Confocal microscopy also confirmed the detection of all strains used in the study.

Conclusion

This novel technique employing TMC nanoparticulate system could be potentially used as a source to raise sera against chitosan in an inexpensive and less laborious manner. Rapid detection of fungal contamination by the polyclonal antibodies could help in devising a quick solution. The polyclonal sera are expected to detect a span of epitopes and provide precise detection. The detection system could be advanced for future applications such as food quality control, crop protection, and human fungal infection detection and treatment.