Potential of different salt forming agents on the formation of chitosan nanoparticles as carriers for protein drug delivery systems

Applications of Chitosan in Prevention and Treatment Strategies of Infectious Diseases

Chitosan is the most commonly investigated functional cationic biopolymer in a wide range of medical applications due to its promising properties such as biocompatibility, biodegradability, and bioadhesivity, as well as its numerous bioactive properties. Within the last three decades, chitosan and its derivatives have been investigated as biomaterials for drug and vaccine delivery systems, besides for their bioactive properties. Due to the functional groups in its structure, it is possible to tailor the delivery systems with desired properties. There has been a great interest in the application of chitosan-based systems also for the prevention and treatment of infectious diseases, specifically due to their antimicrobial, antiviral, and immunostimulatory effects. In this review, recent applications of chitosan in the prevention and treatment of infectious diseases are reviewed, and possibilities and limitations with regards to technical and regulatory aspects are discussed. Finally, the future perspectives on utilization of chitosan as a biomaterial are discussed.

The Chemical Modification to Improve Solubility of Chitosan and Its Derivatives Application, Preparation Method, Toxicity as a Nanoparticles

Chitosan is a functional polymer in the pharmaceutical field, including for nanoparticle drug delivery systems. Chitosan-based nanoparticles are a promising carrier for a wide range of therapeutic agents and can be administered in various routes. Solubility is the main problem for its production and utilization in large-scale industries. Chitosan modifications have been employed to enhance its solubility, including chemical modification. Many reviews have reported the chemical modification but have not focused on the specific characteristics obtained. This review focused on the modification to improve chitosan solubility. Additionally, this review also focused on the application of chitosan derivatives in nanoparticle drug delivery systems since very few similar reviews have been reported. The specific method for chitosan derivative-based nanoparticles was also reported and the latest report of chitosan, chitosan derivative, and chitosan toxicity were also described.

Targeted Nano-Based Systems for the Anti-Obesity Agent's Delivery

Obesity is a global health concern and a chronic disease that is accompanied by excessive fat storage in adipose and nonadipose tissues. An increase in the body-mass index (BMI) is directly proportional to the 2- to 3.9-fold increase in all-cause mortality in obesity. If left untreated for a longer period, obesity-related metabolic, cardiovascular, inflammatory, and malignant diseases reduce life expectancy. Currently, most of the anti-obesity drugs have failed and fallen into disrepute, either due to their ineffectiveness or adverse effects. In this review, depending on their enhanced pharmacokinetic and biodistribution profiles, whether nanocarriers alter the basic properties and bioactivity of anti-obesity drugs used in clinical practice are debated. First, nanocarriers can improve the safety of still-used anti-obesity drugs by lowering their systemic toxicity through increasing targeting efficacy and preventing drug carrier toxicity. Second, when the micro-ribonucleic acids (miRNAs), which are aberrantly expressed in obesity and obesity-related diseases, are encapsulated into nanoparticles, they are effective in multiple obesity-related metabolic pathways and gene networks. Finally, a synergistic anti-obesity effect with low dose and low toxicity can be obtained with the combinatory therapy applied by encapsulating the anti-obesity drug and gene in the same nanocarrier delivery vehicle.

Amino acids and its pharmaceutical applications: A mini review

Amino acids are natural compounds that can be safely used in pharmaceutical applications. Considering the great interest in the amino acids used in the pharmaceutical industry, this article presents an overview of investigations reported in recent years. In this regard, the first sections begin with an introductory description of the properties, classification and safety of amino acids, while in the other sections the most common methods for the preparation of amino acids formulations and their application on solubilization, permeation and stabilization of several active pharmaceutical ingredients are described. Furthermore, available data about the multicomponent systems approach is included. Lastly, the impact of amino acids formulations on therapeutic efficacy is explored. The advantages illustrated suggest that amino acids are capable of improving the biopharmaceutical properties of drugs.

Preparation and characterization of BSA as a model protein loaded chitosan nanoparticles for the development of protein-/peptide-based drug delivery system

Background

The purpose of this study was to develop protein-/peptide-loaded nanoparticle-based delivery system, which can efficiently deliver therapeutic molecules to the lung via pulmonary delivery. The chitosan nanoparticles were prepared by the ionic gelation method, and bovine serum albumin was used as a model protein. These nanoparticles were characterized for size, zeta potential, encapsulation efficiency, cell cytotoxicity, uptake study, release profile and size distribution and uniformity. The chemical interaction of chitosan and protein was studied by XRD and FTIR. The integrity assessment of encapsulated protein into nanoparticle was studied by native and SDS-PAGE gel electrophoresis.

Results

The size and zeta potential of BSA nanoparticles were 193.53 ± 44.97 to 336.36 ± 94.63 and 12.73 ± 0.41 to 18.33 ± 0.96, respectively, with PDI values of 0.35–0.45. The encapsulation efficiency was in the range of 80.73 ± 6.37% to 92.34 ± 1.72%. The cumulative release of the BSA from the nanoparticles was 72.56 ± 6.67% in 2 weeks. The BSA-loaded nanoparticles showed good uptake and no significant cytotoxicity observed into the A549 cell line. In this study, it was also observed that during nanoparticles’ synthesis protein structure and integrity is not compromised. The nanoparticles showed controlled and sustained release with initial burst release. In TEM images, it was shown that nanoparticles’ distribution is uniform within nanometre range.

Conclusion

From this study, it was concluded that nanoparticles prepared by this method are suitable to deliver protein/peptide into the cells without any degradation of protein during process of nanoparticle fabrication.

Development of an M cell targeted nanocomposite system for effective oral protein delivery: preparation, in vitro and in vivo characterization

Background

There is a strong need for non-invasive and patient-friendly delivery systems of protein drugs for long-term therapy. However, oral delivery of protein drugs is a big challenge due to many barriers including instability in the gastrointestinal (GI) tract and low permeability. To overcome the absorption barriers in GI tract and improve the patient compliance, this study aimed to develop an M cell targeted-nanocomposite delivery system of protein drugs.

Results

An aminoclay-protein core complex (AC-Ins) was prepared by using insulin as a model protein and then sequentially coated with Ulex europaeus agglutinin 1 (UEA-1) for M-cell targeting and the pH sensitive polymer, Eudragit® L100 (EUAC-Ins). All nanoparticles were obtained with a high entrapment efficiency (> 90%) and their structural characteristics were confirmed by Fourier transform-infrared spectroscopy, energy dispersive X-ray spectroscopy, and circular dichroism. Among the developed nanoparticles, EUAC-Ins effectively suppressed drug release at pH 1.2, while rapidly released drugs at pH 6.8 due to dissolution of the outer coating layer. The conformational stability of insulin entrapped in EUAC-Ins was well maintained in the presence of proteolytic enzymes. Compared to free insulin, EUAC-Ins increased the membrane transport of insulin by 4.4-fold in M cells. In parallel, oral administration of EUAC-Ins in mice enhanced insulin uptake by 4.1-fold in the intestinal Peyer’s patches and 2.6-fold in intestinal epithelium tissues with normal villi, compared to free insulin. Orally administered EUAC-Ins decreased significantly the blood glucose level in diabetic mice, while the effect of oral insulin solution was negligible.

Conclusion

An M cell targeted-ternary nanocomposite system obtained by dual coating of the aminoclay-protein core complex with UEA-1 and a pH dependent polymer is promising as an effective oral protein delivery carrier.

Design of Mucoadhesive Nanostructured Polyelectrolyte Complexes Based on Chitosan and Hypromellose Phthalate for Metronidazole Delivery Intended to the Treatment of Helicobacter pylori Infections

Metronidazole (MT) is an important drug available for Helicobacter pylori infection treatment. However, in the past few years, this drug has presented effective reduction for infection control, one of the most important reasons is attributed to the reduction of retention time in the stomach environment. Mucoadhesive nanostructured polyelectrolyte complexes (nano PECs) based on chitosan (CS) and hypromellose phthalate (HP) were rationally developed using a full factorial design (21 × 21 × 31), for the incorporation of MT based on the enhancement of the antimicrobial potential against active Helicobacter pylori, in the stomach. Different mass ratios of CS:HP (w/w) were tested, reaching the most promising ratios of 1:0.1, 1:0.5, and 1:1, and two methods of polymers addition (pouring-I and drip-II) were also evaluated. From method I, the obtained particles presented a diameter in the range of 811-1293 nm (Z-average) and a polydispersity index (PDI) between 0.47 and 0.88. By method II, there was a significant reduction in diameter and PDI to 553-739 nm and 0.23 at 0.34, respectively. The drug incorporation also resulted in a reduction in the diameter and PDI of the nano PECs. All samples showed positive zeta potential, about 20 mV, and a high percentage of MT incorporation (±95%). The method factor presented a greater influence on the nano PECs characteristics. Interactions in the system constituents were indicated by the FTIR data. Nano PECs mucoadhesiveness was observed and the composition and charge density were responsible for this phenomenon. MT dissolution evaluation showed the similarity of the dissolution profiles of free and loaded MT, in which almost 100% of the drug was in the simulated gastric medium in 120 min of testing. The in vitro antimicrobial potential against H. pylori of loaded nano PECs were measured and the minimum inhibitory concentration observed for free MT was >2000 µg/mL, while for the incorporated MT lower values were observed, showing an increase in the encapsulated MT activity.

Potential and Applications of Nanocarriers for Efficient Delivery of Biopharmaceuticals

During the past two decades, the clinical use of biopharmaceutical products has markedly increased because of their obvious advantages over conventional small-molecule drug products. These advantages include better specificity, potency, targeting abilities, and reduced side effects. Despite the substantial clinical and commercial success, the macromolecular structure and intrinsic instability of biopharmaceuticals make their formulation and administration challenging and render parenteral delivery as the only viable option in most cases. The use of nanocarriers for efficient delivery of biopharmaceuticals is essential due to their practical benefits such as protecting from degradation in a hostile physiological environment, enhancing plasma half-life and retention time, facilitating absorption through the epithelium, providing site-specific delivery, and improving access to intracellular targets. In the current review, we highlight the clinical and commercial success of biopharmaceuticals and the overall applications and potential of nanocarriers in biopharmaceuticals delivery. Effective applications of nanocarriers for biopharmaceuticals delivery via invasive and noninvasive routes (oral, pulmonary, nasal, and skin) are presented here. The presented data undoubtedly demonstrate the great potential of combining nanocarriers with biopharmaceuticals to improve healthcare products in the future clinical landscape. In conclusion, nanocarriers are promising delivery tool for the hormones, cytokines, nucleic acids, vaccines, antibodies, enzymes, and gene- and cell-based therapeutics for the treatment of multiple pathological conditions.

Single enzyme nanoparticle, an effective tool for enzyme replacement therapy

The term "single enzyme nanoparticle" (SEN) refers to a chemically or biologically engineered single enzyme molecule. SENs are distinguished from conventional protein nanoparticles in that they can maintain their individual structure and enzymatic activity following modification. Furthermore, SENs exhibit enhanced properties as biopharmaceuticals, such as reduced antigenicity, and increased stability and targetability, which are attributed to the introduction of specific moieties, such as poly(ethylene glycol), carbohydrates, and antibodies. Enzyme replacement therapy (ERT) is a crucial therapeutic option for controlling enzyme-deficiency-related disorders. However, the unfavorable properties of enzymes, including immunogenicity, lack of targetability, and instability, can undermine the clinical significance of ERT. As shown in the cases of Adagen®, Revcovi®, Palynziq®, and Strensiq®, SEN can be an effective technology for overcoming these obstacles. Based on these four licensed products, we expect that additional SENs will be introduced for ERT in the near future. In this article, we review the concepts and features of SENs, as well as their preparation methods. Additionally, we summarize different types of enzyme deficiency disorders and the corresponding therapeutic enzymes. Finally, we focus on the current status of SENs in ERT by reviewing FDA-approved products.

Chitosan-based nitric oxide-releasing dressing for anti-biofilm and in vivo healing activities in MRSA biofilm-infected wounds

Bacterial biofilms on wounds impair the healing process and often lead to chronic wounds. Chitosan is a well-known biopolymer with antimicrobial and anti-biofilm effects. S-nitrosoglutathione (GSNO) has been identified as a promising nitric oxide (NO) donor to defend against pathogenic biofilms and enhance wound healing activities. In this study, we prepared NO-releasing chitosan film (CS/NO film) and evaluated its anti-biofilm activity and in vivo wound healing efficacy against methicillin-resistant Staphylococcus aureus (MRSA) biofilm-infected wounds in diabetic mice. The in vitro release study showed sustained release of NO over 3 days in simulated wound fluid. The CS/NO film significantly enhanced antibacterial activity against MRSA by > 3 logs reduction in bacterial viability. Moreover, CS/NO film exhibited a 3-fold higher anti-biofilm activity than the control and CS film. In in vivo MRSA biofilm-infected wounds, the CS/NO film-treated group showed faster biofilm dispersal, wound size reduction, epithelialization rates, and collagen deposition than the untreated and CS film-treated groups. Therefore, the CS/NO film investigated in this study could be a promising approach for the treatment of MRSA biofilm-infected wounds.

Recent Advancements in Non-Invasive Formulations for Protein Drug Delivery

Advancements in biotechnology and protein engineering expand the availability of various therapeutic proteins including vaccines, antibodies, hormones, and growth factors. In addition, protein drugs hold many therapeutic advantages over small synthetic drugs in terms of high specificity and activity. This has led to further R&D investment in protein-based drug products and an increased number of drug approvals for therapeutic proteins. However, there are many biological and biopharmaceutical obstacles inherent to protein drugs including physicochemical and enzymatic destabilization, which limit their development and clinical application. Therefore, effective formulations of therapeutic proteins are needed to overcome the various physicochemical and biological barriers. In current medical practice, protein drugs are predominantly available in injectable formulations, which have disadvantages including pain, the possibility of infection, high cost, and low patient compliance. Consequently, non-invasive drug delivery systems for therapeutic proteins have gained great attention in the research and development of biomedicines. Therefore, this review covers the various formulation approaches to optimizing the delivery properties of protein drugs with an emphasis on improving bioavailability and patient compliance. It provides a comprehensive update on recent advancements in nanotechnologies with regard to non-invasive protein drug delivery systems, which is also categorized by the route of administrations including oral, nasal, transdermal, pulmonary, ocular, and rectal delivery systems.

The roles of short and long chain fatty acids on physicochemical properties and improved cancer targeting of albumin-based fattigation-platform nanoparticles containing doxorubicin

The aim of this study was to investigate the impact of different chain length fatty acids on physicochemical properties and cancer targeting of fattigation-platform nanoparticles (NPs). Two different types of fatty acids (short chain, 2-hydroxybutyric acid, C4; long chain, oleic acid, C18:1) were successfully conjugated to human serum albumin (HSA) via simple 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) coupling reaction. These conjugates readily formed HSA-C4 and HSA-C18:1 NPs which showed good stability in serum and desirable biocompatibility with normal cell line (HEK293T). Doxorubicin hydrochloride (DOX) was efficiently loaded into NPs by incubation process via electrostatic interaction. The structure, morphology, and texture of DOX-loaded NPs were characterized by Transmission electron microscopy (TEM) equipped with Energy-dispersive X-ray spectroscopy (EDS). The initial burst release of DOX-loaded NPs was controlled by the presence and chain length of fatty acids. In vitro cytotoxicity studies with three cancer cell lines (A549, HT-29, and PANC-1) suggested that fattigation-platform NPs have distinctive cytotoxic effects compared to Doxil^®. Confocal microscopy and flow cytometry exhibited that the cellular uptake of DOX-loaded NPs was varied by the different chain lengths of fatty acids. It was evident that the chain length of fatty acids in the fattigation-platform NPs could play a vital role in varying physicochemical properties and cancer cell targeting of NPs.