Design, characterization and ex vivo evaluation of chitosan film integrating of insulin nanoparticles composed of thiolated chitosan derivative for buccal delivery of insulin

Biopolymer Drug Delivery Systems for Oromucosal Application: Recent Trends in Pharmaceutical R&D

Oromucosal drug delivery, both local and transmucosal (buccal), is an effective alternative to traditional oral and parenteral dosage forms because it increases drug bioavailability and reduces systemic drug toxicity. The oral mucosa has a good blood supply, which ensures that drug molecules enter the systemic circulation directly, avoiding drug metabolism during the first passage through the liver. At the same time, the mucosa has a number of barriers, including mucus, epithelium, enzymes, and immunocompetent cells, that are designed to prevent the entry of foreign substances into the body, which also complicates the absorption of drugs. The development of oromucosal drug delivery systems based on mucoadhesive biopolymers and their derivatives (especially thiolated and catecholated derivatives) is a promising strategy for the pharmaceutical development of safe and effective dosage forms. Solid, semi-solid and liquid pharmaceutical formulations based on biopolymers have several advantageous properties, such as prolonged residence time on the mucosa due to high mucoadhesion, unidirectional and modified drug release capabilities, and enhanced drug permeability. Biopolymers are non-toxic, biocompatible, biodegradable and may possess intrinsic bioactivity. A rational approach to the design of oromucosal delivery systems requires an understanding of both the anatomy/physiology of the oral mucosa and the physicochemical and biopharmaceutical properties of the drug molecule/biopolymer, as presented in this review. This review summarizes the advances in the pharmaceutical development of mucoadhesive oromucosal dosage forms (e.g., patches, buccal tablets, and hydrogel systems), including nanotechnology-based biopolymer nanoparticle delivery systems (e.g., solid lipid particles, liposomes, biopolymer polyelectrolyte particles, hybrid nanoparticles, etc.).

Exploring film forming ability and improving its bioadhesiveness by thiolation of mucilaginous polysaccharides from Cassia uniflora seeds for drug delivery application

The objectives of the present work were to explore film forming ability of mucilaginous polysaccharides obtained from Cassia uniflora seeds and improving its bioadhesive potential by thiolation for drug delivery and other applications. Thiolation was achieved by esterification reaction with thioglycolic acid. The modification was confirmed by performing and comparing its zeta potential, DSC, and spectrophotometric characterization by FTIR and NMR with unmodified mucilaginous polysaccharide. The modified mucilaginous polysaccharides FTIR spectra showed an additional absorption band at 2565 cm-1 and new shifts appeared in the 1H (δ 3.24 and at δ 3.44 ppm) and 13C NMR spectra's (21.56 ppm) confirming the esterification of mucilaginous polysaccharides. The prepared films of thiolated and unmodified mucilaginous polysaccharides were evaluated for various parameters like thickness, pH, and weight measurement, The film formulation had a thickness of 0.16 to 0.18 mm, pH in the range of 6.79 to 7.09 and weight uniformity 0.89 to 0.94 mg. The results reveal that the films based on thiolated material improved bioadhesive properties after thiolation. The SEM photographs revealed a smooth surface of film formulations. The diclofenac-loaded film of thiolated mucilaginous polysaccharide also showed >1.5-fold an increase in in-vitro drug release and exhibited non Fickian transport mechanism. These findings could increase the possible applications of chemically modified-thiolated mucilaginous polysaccharides of Cassia uniflora seeds in drug delivery.

Buccal delivery of small molecules and biologics: Of mucoadhesive polymers, films, and nanoparticles - An update

Buccal delivery of small and large molecules is an attractive route of administration that has been studied extensively over the past few decades. This route bypasses first-pass metabolism and can be used to deliver therapeutics directly to systemic circulation. Moreover, buccal films are efficient dosage forms for drug delivery due to their simplicity, portability, and patient comfort. Films have traditionally been formulated using conventional techniques, including hot-melt extrusion and solvent casting. However, newer methods are now being exploited to improve the delivery of small molecules and biologics. This review discusses recent advances in buccal film manufacturing, using the latest technologies, such as 2D and 3D printing, electrospraying, and electrospinning. This review also focuses on the excipients used in the preparation of these films, with emphasis on mucoadhesive polymers and plasticizers. Along with advances in manufacturing technology, newer analytical tools have also been used for the assessment of permeation of the active agents across the buccal mucosa, the most critical biological barrier and limiting factor of this route. Additionally, preclinical and clinical trial challenges are discussed, and some small molecule products already on the market are explored.

Advances in formulation and manufacturing strategies for the delivery of therapeutic proteins and peptides in orally disintegrating dosage forms

Therapeutic proteins and peptides (TPPs) are increasingly favoured above small drug molecules due to their high specificity to the site of action and reduced adverse effects resulting in increased use of these agents for medical treatments and therapies. Consequently, there is a need to formulate TPPs in dosage forms that are accessible and suitable for a wide range of patient groups as the use of TPPs becomes increasingly prevalent in healthcare settings worldwide. Orally disintegrating dosage forms (ODDF) are formulations that can ensure easy-to-administer medication to a wider patient population including paediatrics, geriatrics and people in low-resource countries. There are many challenges involved in developing suitable pharmaceutical strategies to protect TPPs during formulation and manufacturing, as well as storage, and maintenance of a cold-chain during transportation. This review will discuss advances being made in the research and development of pharmaceutical and manufacturing strategies used to incorporate various TPPs into ODDF systems.

Oromucosal delivery of macromolecules: Challenges and recent developments to improve bioavailability

Owing to their biological diversity, high potency, good tolerability, low immunogenicity, site-specific activity, and great efficacy, macromolecular drugs (i.e., proteins and peptides, antibodies, hormones, nucleic acids, vaccines, etc.) are extensively used as diagnostics, prophylactics, and therapeutics in various diseases. To overcome drawbacks associated with parenteral (invasive) delivery of macromolecules as well as to preserve their therapeutic integrity, oromucosal route (sublingual and buccal) has been proven efficient alternate port of delivery. This review aims to summarize challenges associated with oromucosal route and overtime developments in conventional delivery systems with special emphasis on most recent delivery strategies. Over the past few decades, significant efforts have been made for improving the oromucosal absorption of macromolecules by employing chemical penetration enhancers (CPE), enzyme inhibitors, chemical modification of drug structure (i.e., lipidation, PEGylation, etc.), and mucoadhesive materials in the form of buccal tablets, films (or patches), sprays, fast disintegrating tablets, and microneedles. Adaptation of adjunct strategies (e.g., iontophoresis in conjunction with CPE) has shown significant improvement in oromucosal absorption of macromolecules; however, these approaches were also associated with many drawbacks. To overcome these shortcomings and to further improve therapeutic outcomes, specialized delivery devices called "hybrid nanosystems" have been designed in recent times. This newer intervention showed promising potential for promoting oromucosal absorption and absolute bioavailability of macromolecules along with improved thermostability (cold chain free storage), enabling self-administration, site-specific activity, improving therapeutic efficacy and patient compliance. We anticipate that tailoring of hybrid nanosystems to clinical trials as well as establishing their short- and long-term safety profile would substantiate their therapeutic value as pharmaceutical devices for oromucosal delivery of macromolecules.

Development of an Insulin Nano-Delivery System through Buccal Administration

AIM

To develop a new nano-delivery system for insulin buccal administration.

BACKGROUND

Biodegradable polymeric nanoparticles (PNPs) had viewed countless breakthroughs in drug delivery systems. The main objective of PNPs application in delivering and carrying different promising drugs is to make sure that the drugs being delivered to their action sites. As a result maximizing the desired effect and overcoming their limitations and drawbacks.

OBJECTIVES

The main goals of this study were to produce an insulin consumable nano-delivery system for buccal administration and enhance the mucoadhesive effect in sustaining insulin release.

METHODS

Water in oil in water (W-O-W) microemulsion solvent evaporation technique was used for the preparation of nanoparticles consisting from positively charged poly (D, L-lactide-co-glycolide) coated with chitosan and loaded with insulin. Later, a consumable buccal film was prepared by the spin coating method and loaded with the previously prepared nanoparticles.

RESULTS

The newly prepared nanoparticle was assessed in terms of size, charge and surface morphology using a Scanning Electron Microscope (SEM), zeta potential, Atomic Force Microscope (AFM), and Fourier Transform Infra-red (FTIR) spectroscopy. An in-vitro investigation of the insulin release, from nanoparticles and buccal film, demonstrated controlled as well as sustained delivery over 6 hrs. The cumulative insulin release decreased to about (28.9%) with buccal film in comparing with the nanoparticle (50 %).

CONCLUSION

The buccal film added another barrier for insulin release. Therefore, the release was sustained.

Recent Advancements and Patents on Buccal Drug Delivery Systems: A Comprehensive Review

The major requirement for a dosage form to be successful is its ability to penetrate the site of application and the bioavailability of the drug released from the dosage form. The buccal drug delivery is an influential route to deliver the drug into the body. Here, in this context, various novel approaches that include lipoidal carriers like ethosomes, transferosomes, niosomes etc. and electrospun nanofibers are discussed, with respect to buccal drug delivery. These carriers can be easily incorporated into buccal dosage forms like patches and gels that are responsible for increased permeation across the buccal epithelium. The in vivo methods of evaluation on animal models are conscribed here. The novel biocarriers of lipoidal and non-lipoidal nature can be utilized by loading the drug into them, which are helpful in preventing drug degradation and other drawbacks as compared to conventional formulations. The globally patented buccal formulations give us a wide context in literature about the patents filed and granted in the recent years. When it comes to patient compliance, age is an issue, which is also solved by the buccal route. The pediatric buccal formulations are researched for the customization to be delivered to children. Diseases like mouth ulcers, oral cancer, Parkinson's disease, aphthous stomatitis etc. have been successfully treated through the buccal route, which infers that the buccal drug delivery system is an effective and emerging area for formulation and development in the field of pharmaceutics.

An Updated Overview of the Emerging Role of Patch and Film-Based Buccal Delivery Systems

Buccal mucosal membrane offers an attractive drug-delivery route to enhance both systemic and local therapy. This review discusses the benefits and drawbacks of buccal drug delivery, anatomical and physiological aspects of oral mucosa, and various in vitro techniques frequently used for examining buccal drug-delivery systems. The role of mucoadhesive polymers, penetration enhancers, and enzyme inhibitors to circumvent the formulation challenges particularly due to salivary renovation cycle, masticatory effect, and limited absorption area are summarized. Biocompatible mucoadhesive films and patches are favored dosage forms for buccal administration because of flexibility, comfort, lightness, acceptability, capacity to withstand mechanical stress, and customized size. Preparation methods, scale-up process and manufacturing of buccal films are briefed. Ongoing and completed clinical trials of buccal film formulations designed for systemic delivery are tabulated. Polymeric or lipid nanocarriers incorporated in buccal film to resolve potential formulation and drug-delivery issues are reviewed. Vaccine-enabled buccal films have the potential ability to produce both antibodies mediated and cell mediated immunity. Advent of novel 3D printing technologies with built-in flexibility would allow multiple drug combinations as well as compartmentalization to separate incompatible drugs. Exploring new functional excipients with potential capacity for permeation enhancement of particularly large-molecular-weight hydrophilic drugs and unstable proteins, oligonucleotides are the need of the hour for rapid advancement in the exciting field of buccal drug delivery.

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.

Nanocomposite systems for precise oral delivery of drugs and biologics

Oral delivery is considered the favoured route of administration for both local and systemic delivery of active molecules. Formulation of drugs in conventional systems and nanoparticles has provided opportunities for targeting the gastrointestinal (GI) tract, increasing drug solubility and bioavailability. Despite the achievements of these delivery approaches, the development of a product with the ability of delivering drug molecules at a specific site and according to patients' needs remains a challenging endeavour. The complexity of the physicochemical properties of colloidal systems, their stability in different regions of the gastrointestinal tract, and interaction with the restrictive biological barriers hampered their success for oral precise medicine. To overcome these issues, nanoparticles have been combined with polymers to create hybrid nanosystems, namely nanocomposites. They offer enormous possibilities of structural and mechanical modifications to both nanoparticles and polymeric matrixes to generate systems with new properties, functions, and applications for oral delivery. In this review, nanocomposites' physicochemical and functional properties intended to target specific regions of the GI tract-oral cavity, stomach, small bowel, and colon-are analysed. In parallel, it is provided an insight in the nanocomposite solutions for oral delivery intended for systemic and local absorption, together with a focus on inflammatory bowel diseases (IBDs). Additional difficulties in managing IBD related to the alteration in the physiology of the intestine are described. Finally, future perspectives and opportunities for advancement in this field are discussed.

Solid lipid nanoparticle-loaded mucoadhesive buccal films - Critical quality attributes and in vitro safety & efficacy

The objective of this work was to develop and characterize solid lipid nanoparticle (SLN)-loaded mucoadhesive films to reveal their potential as successful drug formulations. SLNs based on lipid (Lipoid S100) and surfactant (polysorbate 80) were prepared using the solvent-injection method, and their properties examined using experimental designs. Further, the marker coumarin 6 (C6) was solubilized in the particles as a model for a lipophilic drug. Lipid and surfactant concentrations influenced the particle size, while C6 had minor impact. The particle size distribution was narrow and the storage stability satisfactory for 4 months (4 ℃). The incorporation of the nanoparticles into a film matrix consisting of HPMC and glycerol, increased film thickness and flexibility, and slightly decreased the mechanical strength. The mucin interaction and disintegration time of the films were unimpaired. Film uniformity was satisfactory. Solubilisation in SLNs reduced the rate and extent of permeation of C6 through a monolayer of mucus-producing HT29-MTX cells. When the particles were incorporated into the mucoadhesive film, this effect was compensated for. In conclusion, this project was a first step in the successful development of an SLN-loaded mucoadhesive film formulation and served its purpose in revealing the formulation's uniformity, mucoadhesiveness and biocompatibility.

Effect of solvents and cellulosic polymers on quality attributes of films loaded with a poorly water-soluble drug

The combined effect of solvent, cellulosic polymer, and a poorly water-soluble drug, fenofibrate (FNB) on solution-cast pharmaceutical film quality attributes, e.g., morphology, drug recrystallization, content uniformity, mechanical properties, dissolution rate and supersaturation level, was investigated. Film morphology, content uniformity, and mechanical properties were impacted by the extent of FNB recrystallization which was strongly affected by FNB solubility in the solvent as compared to the polymer type, hydroxypropyl methylcellulose or hydroxypropyl cellulose. FNB recrystallization affected drug dissolution rates and supersaturation under non-sink conditions. Specifically, the area under the curve linearly correlated with recrystallization. After one-year storage, FNB recrystallization reached very high levels even for the films with no initial recrystallization, suggesting low initial crystallinity does not guarantee stability. Thus, uncontrolled recrystallization and poor time-stability would be unavoidable for solution-cast films. Overall, both the polymer and the solvent strongly impact drug recrystallization, film structure, mechanical properties, dissolution rate, and supersaturation.

Drug-Loaded Lipid-Core Micelles in Mucoadhesive Films as a Novel Dosage Form for Buccal Administration of Poorly Water-Soluble and Biological Drugs

The aim of the study was to develop a novel buccal dosage form to transport rhodamine 123 and human insulin as models for poorly water-soluble and biological drugs, using lipid-core micelles (LCMs)-loaded mucoadhesive films. LCMs were synthesized by a low-energy hot emulsification process, yielding spherically shaped, small-sized, monodispersed and negatively charged carriers with high entrapment efficiency. In vitro release studies demonstrated a higher release of insulin rather than rhodamine from LCMs in simulated physiological conditions, due to an initial burst release effect; however, both release profiles are mainly explained by a diffusion mechanism. Furthermore, LCMs-loaded mucoadhesive films were manufactured and preserved with similar mechanical properties and optimal mucoadhesive behavior compared to nonloaded films. Ex vivo permeation experiments using excised porcine buccal epithelium reveal that both rhodamine and insulin-loaded LCM films elicited a significantly enhanced permeation effect compared to LCMs in suspension and free drugs in solution as controls. Hence, LCMs-loaded mucoadhesive films are suitable as buccal dosage form for the transport and delivery of rhodamine 123 and insulin, as models for poorly water-soluble and biological drugs, respectively.

Quaternary Ammonium Chitosans: The Importance of the Positive Fixed Charge of the Drug Delivery Systems

As a natural polysaccharide, chitosan has good biocompatibility, biodegradability and biosecurity. The hydroxyl and amino groups present in its structure make it an extremely versatile and chemically modifiable material. In recent years, various synthetic strategies have been used to modify chitosan, mainly to solve the problem of its insolubility in neutral physiological fluids. Thus, derivatives with negative or positive fixed charge were synthesized and used to prepare innovative drug delivery systems. Positively charged conjugates showed improved properties compared to unmodified chitosan. In this review the main quaternary ammonium derivatives of chitosan will be considered, their preparation and their applications will be described to evaluate the impact of the positive fixed charge on the improvement of the properties of the drug delivery systems based on these polymers. Furthermore, the performances of the proposed systems resulting from in vitro and ex vivo experiments will be taken into consideration, with particular attention to cytotoxicity of systems, and their ability to promote drug absorption.

Ionic liquid-mediated delivery of insulin to buccal mucosa

Buccal drug delivery offers a potential non-invasive means of delivering therapeutics to patients. Despite the promise, the feasibility of transporting proteins and peptides into systemic circulation from buccal administration remains a daunting challenge. Here, we report the fabrication of a biodegradable polymeric patch for buccal delivery of insulin using chitosan as the mucoadhesive matrix and ionic liquids (ILs)/deep eutectic solvent (DES) as the transport facilitator. Insulin is mixed with ILs/DES made from Choline and Geranic acid (CAGE) to form a viscoelastic CAGE gel and sandwiched between two layers of a biodegradable polymer. The rheological properties of the CAGE gel were dominated by the elastic modulus and suggested a solid-like viscoelastic behavior. CAGE induced a 7-fold increase in the cumulative insulin transport across the ex vivo porcine buccal tissue (~26% of loaded insulin) which was also confirmed by confocal microscopy. The CAGE/insulin patches placed in the rat buccal pouch in vivo lowered blood glucose levels in a dose-dependent manner (up to 50% drop recorded) with no obvious tissue damage at the application site. The pharmacokinetic performance of the delivered insulin indicated a sustained profile as serum insulin levels plateaued after 3 h for the duration of study. The safety and efficacy of the polymeric patch using insulin as a model drug holds significant promise as a platform technology to deliver injectables through the buccal route.

Thiolated Chitosans: A Multi-talented Class of Polymers for Various Applications

Various properties of chitosan can be customized by thiolation for very specific needs in a wide range of application areas. Since the discovery of thiolated chitosans, many studies have proven their advantageous characteristics, such as adhesion to biological surfaces, adjustable cross-linking and swelling behavior, controllable drug release, permeation as well as cellular uptake enhancement, inhibition of efflux pumps and enzymes, complexation of metal ions, antioxidative properties, and radical scavenging activity. Simultaneously, these polymers remain biodegradable without increased toxicity. Within this Review, an overview about the different possibilities to covalently attach sulfhydryl ligands to the polymeric backbone of chitosan is given, and the resulting versatile physiochemical properties are discussed in detail. Furthermore, the broad spectrum of applications for thiolated chitosans in science and industry, ranging from their most advanced use in pharmaceutical and medical science over wastewater treatment to the impregnation of textiles, is addressed.

Advances in Nanoparticulate Drug Delivery Approaches for Sublingual and Buccal Administration

The sublingual and buccal routes of administration have significant advantages for both local and systemic drug delivery. They have shown to be an effective alternative to the traditional oral route, especially when fast onset of action is required. Drugs can be rapidly and directly absorbed into the systemic circulation via venous drainage to the superior vena cava. Therefore, they are useful for drugs that undergo high hepatic clearance or degradation in the gastrointestinal tract, and for patients that have swallowing difficulties. Drugs administered via the sublingual and buccal routes are traditionally formulated as solid dosage forms (e.g., tablets, wafers, films, and patches), liquid dosage forms (e.g., sprays and drops), and semi-solid dosage forms (e.g., gels). Conventional dosage forms are commonly affected by physiological factors, which can reduce the contact of the formulation with the mucosa and lead to unpredictable drug absorption. There have been a number of advances in formulation development to improve the retention and absorption of drugs in the buccal and sublingual regions. This review will focus on the physiological aspects that influence buccal and sublingual drug delivery and the advances in nanoparticulate drug delivery approaches for sublingual and buccal administration. The clinical development pipeline with formulations approved and in clinical trials will also be addressed.

Preparation and characterization of insulin chitosan-nanoparticles loaded in buccal films

Chitosan nanoparticles loaded with insulin (IN-CS-NPs) were prepared using ionic gelation method using sodium tripolyphophate as a crosslinker. Later the nanoparticles (NPs) were dispersed in buccal films. The physicochemical properties and the morphology of the nanoparticles were characterized. The stability and release of insulin from the NPs were investigated. Buccal films were prepared separately and their properties such as the weight, thickness, pH, and mucoadhesiveness were investigated. The best film was used to disperse IN-CS-NPs and the loaded film was characterized. The nanoparticles size, polydispersity index, zeta potential, entrapment efficacy, and the loading capacity were 325.07 ± 1.32 nm, 0.38 ± 0.03 and 8.41 ± 0.80 mV, and 73.27 and 18.03%, respectively. The weight and thickness of the loaded film with IN-CS-NPs were 23.0 ± 3.0 mg and 0.32 ± 0.04 mm, respectively and the mucoadhesive force was 2.3 ± 0.2 N. The drug was stable in the NPs and in the films for three months, and its release was controlled by the film and the nanoparticles. Finally, the films loaded with IN-CS-NPs were studied in vivo and were compared to the commercially available insulin. The films prepared in this work were found to decrease glucose level significantly in diabetic rats.

The Effect of Inkjet Printing over Polymeric Films as Potential Buccal Biologics Delivery Systems

The buccal mucosa appears as a promissory route for biologic drug administration, and pharmaceutical films are flexible dosage forms that can be used in the buccal mucosa as drug delivery systems for either a local or systemic effect. Recently, thin films have been used as printing substrates to manufacture these dosage forms by inkjet printing. As such, it is necessary to investigate the effects of printing biologics on films as substrates in terms of their physical and mucoadhesive properties. Here, we explored solvent casting as a conventional method with two biocompatible polymers, hydroxypropyl methylcellulose, and chitosan, and we used electrospinning process as an electrospun film fabrication of polycaprolactone fibers due to its potential to elicit mucoadhesion. Lysozyme was used as biologic drug model and was formulated as a solution for printing by thermal inkjet printing. Films were characterized before and after printing by mechanical and mucoadhesive properties, surface, and ultrastructure morphology through scanning electron microscopy and solid state properties by thermal analysis. Although minor differences were detected in micrographs and thermograms in all polymeric films tested, neither mechanical nor mucoadhesive properties were affected by these differences. Thus, biologic drug printing on films was successful without affecting their mechanical or mucoadhesive properties. These results open way to explore biologics loading on buccal films by inkjet printing, and future efforts will include further in vitro and in vivo evaluations.

Buccal delivery of small molecules and biologics: of mucoadhesive polymers, films, and nanoparticles

Buccal delivery of macromolecules (biologics) sets a great challenge for researchers. Although several niche small molecule products have been approved as simple sprays, tablets and oral films, it is not simply a case of adapting existing technologies to biologics. Buccal delivery of insulin has reached clinical trials with two approaches: oromucosal sprays of the peptide with permeation enhancers, and embedded gold nanoparticles in a dissolvable film. However, neither of these approaches have led to FDA approvals likely due to poor efficacy, submaximal peptide loading in the dosage form, and to wide intra-subject variability in pharmacokinetics and pharmacodynamics. It is likely however that printed film designs with lower molecular weight stable biotech payloads including lipophilic glucagon-like 1 (GLP-1) agonists and macrocycles with long half-lives will generate greater efficacy than was achieved to date for insulin.

Development of Polyethylene Glycol and Hard Fat-Based Mucoadhesive Tablets Containing Various Types of Polyvinyl Alcohols as Mucoadhesive Polymers for Buccal Application

Topical drug application has the advantage of avoiding systemic side effects. We attempted to develop a long-acting matrix-type tablet containing indomethacin (IM) with low physical stimulus and potent mucoadhesive force to treat pain caused by oral aphtha. A mixture of polyethylene glycol (PEG) and hard fat was used as the tablet base. Ethylcellulose was added to the base in an attempt to control drug release. Tablets with PEG as a base were also prepared for comparison. Polyvinyl alcohols (PVAs) with various degrees of saponification were added to increase the mucoadhesive force. From the optical microscopic observations, formulations using PEG and hard fat exhibit PEG/hard fat dispersions caused by the stabilizing effects of PVA. Although the tablets using PEG and hard fat showed sufficient adhesiveness and sustained drug release, those using PEG as the base did not. Drug release was controlled by the amount of hard fat and the saponification degree of PVA. The drug release rate was most increased in a tablet containing PVA with an intermediate degree of saponification, PEG and hard fat. From differential scanning calorimetry and powder X-ray diffraction, IM was considered to exist in the molecular phase. From the results of buccal administration of tablets to rats, highest tissue concentrations were observed in the tablet containing PVA with the intermediate degree of saponification using PEG and hard fat, and the plasma concentrations were sufficiently low in comparison.

Buccal Dosage Forms: General Considerations for Pediatric Patients

The development of an appropriate dosage form for pediatric patients needs to take into account several aspects, since adult drug biodistribution differs from that of pediatrics. In recent years, buccal administration has become an attractive route, having different dosage forms under development including tablets, lozenges, films, and solutions among others. Furthermore, the buccal epithelium can allow quick access to systemic circulation, which could be used for a rapid onset of action. For pediatric patients, dosage forms to be placed in the oral cavity have higher requirements for palatability to increase acceptance and therapy compliance. Therefore, an understanding of the excipients required and their functions and properties needs to be particularly addressed. This review is focused on the differences and requirements relevant to buccal administration for pediatric patients (compared to adults) and how novel dosage forms can be less invasive and more acceptable alternatives.

Formulation, in vitro evaluation and kinetic analysis of chitosan-gelatin bilayer muco-adhesive buccal patches of insulin nanoparticles

The present study was performed to optimise the formulation of a muco-adhesive buccal patch for insulin nanoparticles (NPs) delivery. Insulin NPs were synthesised by an ionic gelation technique using N-di methyl ethyl chitosan cysteine (DMEC-Cys) as permeation enhancer biopolymer, tripolyphosphate (TPP) and insulin. Buccal patches were developed by solvent-casting technique using chitosan and gelatine as muco-adhesive polymers. Optimised patches were embedded with 3 mg of insulin-loaded NPs with a homogeneous distribution of NPs in the muco-adhesive matrix, which displayed adequate physico-mechanical properties. The drug release characteristics, release mechanism and kinetics were investigated. Data fitting to Peppas equation with a correlation coefficient indicated that the mechanism of drug release followed an anomalous transport that means drug release was afforded through drug diffusion along with polymer erosion. In vitro drug release, release kinetics, physical and mechanical studies for all patch formulations reflected the ideal characteristics of this buccal patch for the delivery of insulin NPs.

Preparation and physicochemical characterization of topical chitosan-based film containing griseofulvin-loaded liposomes

Griseofulvin is an antifungal drug and is available as oral dosage forms. Development of topical treatment could be advantageous for superficial fungal infections of the skin. In this study, films prepared from the incorporation of griseofulvin-loaded liposomes in chitosan film for topical drug delivery in superficial fungal infections. The properties of the films were characterized regarding mechanical properties, swelling, ability to transmit vapor, drug release, thermal behavior, and antifungal efficacy against Microsporum gypseum and Epidermophyton floccosum. The presence of liposomes led to decreased mechanical properties but lower swelling ratio. Higher amount of drug permeation and rate of flux were obtained by liposomes incorporated in films compared to liposomal formulations. Antifungal efficacy of formulations was confirmed against two species of dermatophytes in vitro. Therefore, two concepts of using vesicular carrier systems and biopolymeric films have been combined and this topical novel composite film has the potential for griseofulvin delivery to superficial fungal infections.

Physicochemical and nanomechanical investigation of electrodeposited chitosan:PEO blends

Cathodic electrodeposition is a bottom up process that is emerging as a simple yet efficient strategy to engineer thin polymeric films with well-defined physicochemical properties.