In vitro techniques to evaluate buccal films

Chitosan-based mucoadhesive films loaded with curcumin for topical treatment of oral cancer

This study aimed to develop mucoadhesive chitosan-based films capable of enhancing the curcumin penetration into the oral mucosa to treat oral cancers. We developed three films containing medium molecular weight chitosan (190-310 KDa) and other excipients (polyvinyl alcohol, Poloxamer®407, and propylene glycol) that have proven to be compatible with each other and with curcumin in thermal analyses. The films were smooth, flexible, and precipitates free, with uniform weight and thickness, pH compatible with the oral mucosa, resistance to traction, and entrapped curcumin in a high proportion. They also exhibited necessary swelling and mucoadhesion for tissue adherence. Ex vivo penetration studies proved that the films significantly increased the penetration of curcumin into the oral mucosa compared to control, even when the mucosa was subjected to a condition of simulated salivation. Curcumin exhibited cytotoxic activity in vitro in the two head and neck cancer cell lines (FaDu, SCC-9) at doses close to those found in penetration studies with the films. When combined with radiotherapy, curcumin demonstrated superiority over single doses of radiotherapy at 4, 8, and 12 Gy. Therefore, the developed films may represent a promising alternative for the topical treatment of oral tumors.

PVA-based formulations as a design-technology platform for orally disintegrating film matrices

In the majority of pharmaceutical applications, polymers are employed extensively in a diverse range of pharmaceutical products, serving as indispensable components of contemporary solid oral dosage forms. A comprehensive understanding of the properties of polymers and selection the appropriate methods of characterization is essential for the design and development of novel drug delivery systems and manufacturing processes. Orally disintegrating film (ODF) formulations are considered to be a potential substitute to traditional oral dosage forms and an alternative method of drug administration for children and uncooperative adult patients, including those with swallowing difficulties. A multitude of pharmaceutical formulations with varying mechanical and biopharmaceutical properties have emerged from the modification of the original polymeric bulk. Here we propose different formulation approaches, i.e. solvent casting (SC), 3D printing (3DP), electrospinning (ES), and lyophilization (LP) that enabled us to adjust the disintegration time and the release profile of poorly water soluble haloperidol (HAL, BCS class II) from PVA (polyvinyl alcohol) based polymer films while maintaining similar hydrogel composition. In this study, the solubility of haloperidol in aqueous solution was improved by the addition of lactic acid. The prepared films were evaluated for their morphology (SEM, micro-CT), physicochemical and biopharmaceutical properties. TMDSC, TGA and PXRD were employed for extensive thermal and structural analysis of fabricated materials and their stability. These results allowed us to establish correlations between preparation technology, structural characteristics and properties of PVA films and to adapt the suitable manufacturing technique of the ODFs to achieve appropriate HAL dissolution behaviour.

Porphyrin Photosensitizers into Polysaccharide-Based Biopolymer Hydrogels for Topical Photodynamic Therapy: Physicochemical and Pharmacotechnical Assessments

Photodynamic therapy (PDT) is an emerging treatment modality that utilizes light-sensitive compounds, known as photosensitizers, to produce reactive oxygen species (ROS) that can selectively destroy malignant or diseased tissues upon light activation. This study investigates the incorporation of two porphyrin structures, 5-(4-hydroxy-3-methoxyphenyl)-10,15,20-tris-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.2.) and 5,10,15,20-tetrakis-(4-acetoxy-3-methoxyphenyl) porphyrin (P2.1.), into hydroxypropyl cellulose (HPC) hydrogels for potential use in topical photodynamic therapy (PDT). The structural and compositional properties of the resulting hydrogels were characterized using advanced techniques such as Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TGA), atomic force microscopy (AFM), UV-Visible (UV-Vis) spectroscopy, and fluorescence spectroscopy. FTIR spectra revealed a slight shift of the main characteristic absorption bands corresponding to the porphyrins and their interactions with the HPC matrix, indicating successful incorporation and potential hydrogen bonding. XRD patterns revealed the presence of crystalline domains within the HPC matrix, indicating partial crystallization of the porphyrins dispersed within the amorphous polymer structure. TGA results indicated enhanced thermal stability of the HPC-porphyrin gels compared to 10% HPC gel, with additional weight loss stages corresponding to the thermal degradation of the porphyrins. Rheological analysis showed that the gels exhibited pseudoplastic behavior and thixotropic properties, with minimal impact on the flow properties of HPC by P2.1., but notable changes in viscosity and shear stress with P2.2. incorporation, indicating structural modifications. AFM imaging revealed a homogeneous distribution of porphyrins, and UV-Vis and fluorescence spectroscopy confirmed the retention of their photophysical properties. Pharmacotechnical evaluations showed that the hydrogels possessed suitable mechanical properties, optimal pH, high swelling ratios, and excellent spreadability, making them ideal for topical application. These findings suggest that the porphyrin-incorporated HPC hydrogels have significant potential as effective therapeutic agents for topical applications.

The dawning era of oral thin films for nutraceutical delivery: From laboratory to clinic

Oral thin films (OTFs) are innovative dosage forms that have gained tremendous attention for the delivery of nutraceuticals. They are ultra-thin, flexible sheets that can be easily placed on the tongue, sublingual or buccal mucosa (inner lining of the cheek). These thin films possess several advantages for nutraceutical delivery including ease of administration, rapid disintegration, fast absorption, rapid onset of action, bypass first-pass hepatic metabolism, accurate dosing, enhanced stability, portability, discreetness, dose flexibility and most importantly consumer acceptance. This review highlights the utilization OTFs for nutraceutical delivery, their composition, criteria for excipient selection, methods of development and quality-based design (QbD) approach to achieve quality product. We have also provided recent case studies representing OTFs as promising platform in delivery of nutraceuticals (plant extracts, bioactive molecules, vitamins, minerals and protein/peptides) and probiotics. Finally, we provided advancement in technologies, recent patents, market analysis, challenges and future perspectives associated with this unique dosage form.

Development of a hydroxypropyl methyl cellulose/polyacrylic acid interpolymer complex formulated buccal mucosa adhesive film to facilitate the delivery of insulin for diabetes treatment

Buccal mucosa administration is a promising method for insulin (INS) delivery with good compliance. However, buccal mucosa delivery systems still face challenges of long-term mucosal adhesion, sustained drug release, and mucosal drug penetration. To address these issues, a double-layer film consisting of a hydroxypropyl methylcellulose/polyacrylic acid interpolymer complex (IPC)-formulated mucoadhesive layer and an ethylcellulose (EC)-formulated waterproof backing layer (IPC/EC film) was designed. Protamine (PTM) and INS were co-loaded in the mucoadhesive layer of the IPC/EC film (PTM-INS-IPC/EC film). In ex vivo studies with porcine buccal mucosa, this film exhibited robust adhesion, with an adhesion force of 120.2 ± 20.3 N/m2 and an adhesion duration of 491 ± 45 min. PTM has been shown to facilitate INS mucosal transfer. Pharmacokinetic studies indicated that the PTM-INS-IPC/EC film significantly improved the absorption of INS, exhibiting a 1.45 and 2.24-fold increase in the area under the concentration-time curve (AUC0-∞) compared to the INS-IPC/EC film and free INS, respectively. Moreover, the PTM-INS-IPC/EC film effectively stabilized the blood glucose levels of type 1 diabetes mellitus (T1DM) rats with post oral glucose administration, maintaining lower glucose levels for approximately 8 h. Hence, the PTM-INS-IPC/EC film provides a promising noninvasive INS delivery system for diabetes treatment.

Design, optimization and pharmaceutical characterization of wound healing film dressings with chloramphenicol and ibuprofen

OBJECTIVE

The aim of the present study was to develop and optimize a wound dressing film loaded with chloramphenicol (CAM) and ibuprofen (IBU) using a Quality by Design (QbD) approach.

SIGNIFICANCE

The two drugs have been combined in the same dressing as they address two critical aspects of the wound healing process, namely prevention of bacterial infection and reduction of inflammation and pain related to injury.

METHODS

Three critical formulation variables were identified, namely the ratios of Kollicoat SR 30D, polyethylene glycol 400 and polyvinyl alcohol. These variables were further considered as factors of an experimental design, and 17 formulations loaded with CAM and IBU were prepared via solvent casting. The films were characterized in terms of dimensions, mechanical properties and bioadhesion. Additionally, the optimal formulation was characterized regarding tensile properties, swelling behavior, water vapor transmission rate, surface morphology, thermal behavior, goniometry, in vitro drug release, cell viability, and antibacterial activity.

RESULTS

The film was optimized by setting minimal values for the folding endurance, adhesive force and hardness. The optimally formulated film showed good fluid handling properties in terms of swelling behavior and water vapor transmission rate. IBU and CAM were released from the film up to 80.9% and 82.5% for 8 h. The film was nontoxic, and the antibacterial activity was prominent against Micrococcus spp. and Streptococcus pyogenes.

CONCLUSIONS

The QbD approach was successfully implemented to develop and optimize a novel film dressing promising for the treatment of low-exuding acute wounds prone to infection and inflammation.

Nanonization and Deformable Behavior of Fattigated Peptide Drug in Mucoadhesive Buccal Films

This study was tasked with the design of mucoadhesive buccal films (MBFs) containing a peptide drug, leuprolide (LEU), or its diverse nanoparticles (NPs), for enhanced membrane permeability via self-assembled nanonization and deformable behavior. An LEU-oleic acid conjugate (LOC) and its self-assembled NPs (LON) were developed. Additionally, a deformable variant of LON (d-LON) was originally developed by incorporating l-α-phosphatidylcholine into LON as an edge activator. The physicochemical properties of LON and d-LON, encompassing particle size, zeta potential, and deformability index (DI), were evaluated. MBFs containing LEU, LOC, and NPs (LON, d-LON) were prepared using the solvent casting method by varying the ratio of Eudragit RLPO and hydroxypropyl methylcellulose, with propylene glycol used as a plasticizer. The optimization of MBF formulations was based on their physicochemical properties, including in vitro residence time, dissolution, and permeability. The dissolution results demonstrated that the conjugation of oleic acid to LEU exhibited a more sustained LEU release pattern by cleaving the ester bond of the conjugate, as compared to the native LEU, with reduced variability. Moreover, the LOC and its self-assembled NPs (LON, d-LON), equivalent to 1 mg LEU doses in MBF, exhibited an amorphous state and demonstrated better permeability through the nanonization process than LEU alone, regardless of membrane types. The incorporation of lauroyl-L-carnitine into the films as a permeation enhancer synergistically augmented drug permeability. Most importantly, the d-LON-loaded buccal films showed the highest permeability, due to the deformability of NPs. Overall, MBF-containing peptide NPs and permeation enhancers have the potential to replace parenteral LEU administration by improving LEU druggability and patient compliance.

Xanthan-carrageenan film containing sesame seed oil: A nanocomposite pharmaceutical platform for trichomoniasis treatment

Trichomoniasis is a common sexually transmitted infection that poses significant complications for women. Challenges in treatment include adverse effects and resistance to standard antimicrobial agents. Given this context, a sesame seed oil nanoemulsion (SONE) was developed and showed anti-Trichomonas vaginalis activity. To facilitate the local application of SONE, a polysaccharide film was developed using xanthan gum (XG) and κ-carrageenan gum (CG). A blend of XG and CG (at 2 %, ratio 1:3) plasticized with glycerol produced a more promising film (XCF) than using the gums individually. The film containing SONE (SONE-XCF) was successfully obtained by replacing the aqueous solvent with SONE via solvent evaporation technique. The hydrophilic SONE-XCF exhibited homogeneity and suitable mechanical properties for vaginal application. Furthermore, SONE-XCF demonstrated mucoadhesive properties and high absorption capacity for excessive vaginal fluids produced in vaginitis. It also had a disintegration time of over 8 h, indicating long retention at the intended site of action. Hemolysis and chorioallantoic membrane tests confirmed the safety of the film. Therefore, SONE-XCF is a biocompatible film with a natural composition and inherent activity against T. vaginalis, possessing exceptional characteristics that make it appropriate for vaginal application, offering an interesting alternative for trichomoniasis treatment.

Evaluation of the impact of tragacanth/xanthan gum interpolymer complexation with chitosan on pharmaceutical performance of gels with secnidazole as potential periodontal treatment

Periodontitis consists a group of dental disorders that affect about 70 % of the world population. The therapy mainly relies on mechanical removing bacterial biofilm, nevertheless, local or systemic antibacterial agents play a key role in treating the acute conditions. Secnidazole is a newer derivative of commonly used metronidazole with high safety profile and broad spectrum of antimicrobial activity. The aim of the study was to evaluate the applicability of polyelectrolyte complex-based hydrogels composed of anionic tragacanth with addition of xanthan gum and cationic chitosan as carriers for buccal/intra pocket delivery of secnidazole. Prepared hydrogels with 5 % and 10 % (w/w) drug content were evaluated pharmaceutically towards inter alia physicomechanical, rheological and thermal properties, drug release kinetics, swelling behavior or antimicrobial activity. Cytotoxicity against human primary umbilical vein endothelial cells was also assessed with two independent method. Stable compositions with secnidazole were obtained, however, various miscibility of the drug with the polymers was noted. By adding chitosan, antibacterial activity and swelling performance of the gels were improved, nevertheless, drop of the mucoadhesiveness was also recorded. Hydrogels with 5 % secnidazole were selected as effective antimicrobial compositions with the highest cytocompatibility. They might be considered as promising for oromucosal application with special attention given to SEC as an alternative locally administered antimicrobial agent.

Development and In Vitro Evaluation of Aceclofenac Buccal Film

AIM

This study aimed to formulate and characterize aceclofenac buccal film formulations made of different polymers and evaluate the effects of polymer type on buccal film properties.

MATERIALS AND METHODS

Five polymer types, namely hydroxypropyl methylcellulose (HPMC), sodium carboxymethylcellulose (SCMC), polyvinyl alcohol (PVA), Eudragit S100, and Eudragit SR100, were used to prepare aceclofenac buccal film formulation either separately or combined by solvent-casting method. These formulations were evaluated in terms of physical appearance, folding test, film weight and thickness, drug content, percentage of elongation, moisture uptake, water vapor permeability, and in vitro drug release.

RESULTS

The addition of Eudragit polymer in most of the produced buccal films was unacceptable with low folding endurance. However, the dissolution profile of buccal films made from PVA and Eudragit SR100 provided a controlled drug release profile.

CONCLUSION

Buccal films can be formulated using different polymers either individually or in combination to obtain the drug release profile required to achieve a desired treatment goal. Furthermore, the property of the buccal films depends on the type and concentration of the polymer used.

Development of Polyvinyl Alcohol/Polyethylene Glycol Copolymer-based Orodispersible Films Loaded with Entecavir: Formulation and In vitro Characterization

PURPOSE

The aim of the study is to prepare entecavir (ETV)-loaded orodispersible films (ODFs) using polyvinyl alcohol (PVA)/polyethylene glycol (PEG) graft copolymer (Kollicoat® IR) as a film-forming agent, and further to evaluate the dissolution rate, mechanical and physicochemical properties of films.

METHODS

ETV-ODFs were prepared by a solvent casting method. The amount of film-forming agent, plasticizer, and disintegrating agent was optimized in terms of the appearance, thickness, disintegration time and mechanical properties of ODFs. The compatibility between the drug and each excipient was conducted under high temperature (60 °C), high humidity (RH 92.5%), and strong light (4500 Lx) for 10 days. The dissolution study of optimal ODFs compared with the original commercial tablet (Baraclude®) was performed using a paddle method in pH 1.0, pH 4.5, pH 6.8, and pH 7.4 media at 37 °C. The morphology of ODFs was observed via scanning electron microscopy (SEM). The mechanical properties such as tensile strength (TS), elastic modulus (EM), and percentage elongation (E%) of ODFs were evaluated using the universal testing machine. The physicochemical properties of ODFs were investigated using X-ray diffraction (XRD), differential scanning calorimetry (DSC), and Fourier transform infrared spectroscopy (FT-IR).

RESULTS

The related substances were less than 0.5% under high temperature, high humidity, and strong light for 10 days when ETV was mixed with excipients. The optimal formulation of ODFs was set as the quality ratio of Kollicoat® IR, glycerol, sodium alginate (ALG-Na): TiO2: MCC+CMC-Na: ETV was 60:9:12:1:1:1. The drug-loaded ODFs were white and translucent with excellent stripping property. The thickness, disintegration time, EM, TS, and E% were 103.33±7.02 μm, 25.31±1.95 s, 25.34±8.69 Mpa, 2.14±0.26 Mpa, and 65.45±19.41 %, respectively. The cumulative drug release from ODFs was more than 90% in four different media at 10 min. The SEM showed that the drug was highly dispersible in ODFs, and the XRD, DSC, and FT-IR results showed that there occurred some interactions between the drug and excipients.

CONCLUSION

In conclusion, the developed ETV-loaded ODFs showed relatively short disintegration time, rapid drug dissolution, and excellent mechanical properties. This might be an alternative to conventional ETV Tablets for the treatment of chronic hepatitis B.

Orodispersible Films: Current Innovations and Emerging Trends

Orodispersible films (ODFs) are thin, mechanically strong, and flexible polymeric films that are designed to dissolve or disintegrate rapidly in the oral cavity for local and/or systemic drug delivery. This review examines various aspects of ODFs and their potential as a drug delivery system. Recent advancements, including the detailed exploration of formulation components, such as polymers and plasticizers, are briefed. The review highlights the versatility of preparation methods, particularly the solvent-casting production process, and novel 3D printing techniques that bring inherent flexibility. Three-dimensional printing technology not only diversifies active compounds but also enables a multilayer approach, effectively segregating incompatible drugs. The integration of nanoparticles into ODF formulations marks a significant breakthrough, thus enhancing the efficiency of oral drug delivery and broadening the scope of the drugs amenable to this route. This review also sheds light on the diverse in vitro evaluation methods utilized to characterize ODFs, ongoing clinical trials, approved marketed products, and recent patents, providing a comprehensive outlook of the evolving landscape of orodispersible drug delivery. Current patient-centric approaches involve developing ODFs with patient-friendly attributes, such as improved taste masking, ease of administration, and enhanced patient compliance, along with the personalization of ODF formulations to meet individual patient needs. Investigating novel functional excipients with the potential to enhance the permeation of high-molecular-weight polar drugs, fragile proteins, and oligonucleotides is crucial for rapid progress in the advancing domain of orodispersible drug delivery.

Immobilization of Papain in Chitosan Membranes as a Potential Alternative for Skin Wounds

Papain (an enzyme from the latex of Carica papaya) is an interesting natural bioactive macromolecule used as therapeutic alternative for wound healing due to debridement action in devitalized or necrotic tissues. However, its use in high doses can induce potential skin irritation and side effects. In this study, experiments explored the ability of chitosan membrane to immobilize papain, consequently improving enzymatic activity and controlling enzyme release. Papain-loading capacity was tested via experiments of force microscopy (AFM), scanning electron microscopy (SEM-FEG), and X-ray diffraction analyses. Fourier transform infrared spectroscopy and thermal analyses assessed the enzyme interactions with the copolymer. The investigation of the feasibility of membranes included pH on the surface, elasticity, and breaking strength measurements. The surface wettability and swelling capacity of different formulations revealed the best formulation for in vitro papain release experiments. The membranes had a transparent, rough, crystalline characteristic, which was homogeneous with the membrane within the neutrality. The immobilization of papain in the chitosan membrane resulted in a decrease in the vibration band characteristic of pure papain, suggesting a displacement in the vibration bands in the FTIR spectrum. The presence of papain decreased hydrophobicity on the surface of the membrane and disturbed the membrane's ability to swell. Chitosan membranes containing papain 2.5% (0.04 g) and 5.0% (0.08 g) preserved feasible properties and improved the enzymatic activity compared (0.87 ± 0.12 AU/mg and 1.59 ± 0.10 AU/mg) with a free papain sample (0.0042 ± 0.001 AU/mg). Concentrations of over 10% (0.16 g) led to phase separation into membranes. Chitosan membranes exhibited a slow papain release behavior adjusted via the Higushi model. The experimental achievements suggest a novel and promising method for the enhancement of papain. The results indicate the potential for prolonged bioactivity for use on wounds.

Drug-Eluting Sutures by Hot-Melt Extrusion: Current Trends and Future Potentials

Surgical site infections (SSIs) may result from surgical procedures requiring a secondary administration of drugs at site or systemically in treating the infection. Drug-eluting sutures containing antimicrobial agents symbolise a latent strategy that precludes a secondary drug administration. It also offers the possibility of delivering a myriad of therapeutic agents to a localised wound site to effect analgesia, anti-inflammation, or the deployment of proteins useful for wound healing. Further, the use of biodegradable drug-eluting sutures eliminates the need for implanting foreign material into the wound, which needs to be removed after healing. In this review, we expound on recent trends in the manufacture of drug-eluting sutures with a focus on the hot-melt extrusion (HME) technique. HME provides a solvent-free, continuous one-step manufacturing conduit for drug-eluting sutures, hence, there is no drying step, which can be detrimental to the drug or suture threads and, thus, environmentally friendly. There is the possibility of combining the technology with additive manufacturing platforms to generate personalised drug-loaded implantable devices through prototyping and scalability. The review also highlights key material requirements for fabricating drug-eluting sutures by HME, as well as quality attributes. Finally, a preview of emerging drug-eluting sutures and advocacy for harmonisation of quality assurance by regulatory authorities that permits quality evaluation of novelty sutures is presented.

Formulation and In Vivo Evaluation of Biofilm Loaded with Silver Sulfadiazine for Burn Healing

Infected burned skin is a life-threatening condition, which may lead to sepsis. The aims of this work are to formulate a biofilm composed of silver sulfadiazine (SSD), chitosan (CS), and sodium alginate (SA), and to evaluate its wound-healing effectiveness. A full factorial design was used to formulate different matrix formulations. The prepared biofilm was tested for physicochemical, and in vitro release. The optimized formulation is composed of 0.833% of CS and 0.75% of SA. The release of SSD almost reached 100% after 6 h. The mechanical properties of the optimized formula were reasonable. The antibacterial activity for the optimized biofilm was significantly higher than that of blank biofilm, which is composed of CS and SA, p = 1.53922 × 10-12. Moreover, the in vivo study showed a 75% reduction in wound width when using the formulated SSD biofilm compared to standard marketed cream (57%) and the untreated group (0%).

Boosting systemic absorption of peptides with a bioinspired buccal-stretching patch

Biopharmaceuticals, including proteins and peptides, have revolutionized the treatment of a wide range of diseases, from diabetes and cardiovascular disorders to virus infections and cancer. Despite their efficacy, most of these macromolecular drugs require parenteral administration because of their high molecular weight and relative instability. Over the past 40 years, only a few oral peptide drugs have entered clinical trials, even when formulated with substantial amounts of permeation enhancers. To overcome the epithelial barrier, devices that inject drugs directly into the gastrointestinal mucosa have been proposed recently. However, the robustness and safety of those complex systems are yet to be assessed. In this study, we introduced an innovative technology to boost drug absorption by synergistically combining noninvasive stretching of the buccal mucosa with permeation enhancers. Inspired by the unique structural features of octopus suckers, a self-applicable suction patch was engineered, enabling strong adhesion to and effective mechanical deformation of the mucosal tissue. In dogs, this suction patch achieved bioavailability up to two orders of magnitude higher than those of the commercial tablet formulation of desmopressin, a peptide drug known for its poor oral absorption. Moreover, systemic exposure comparable to that of the approved oral semaglutide tablet was achieved without further optimization. Last, a first-in-human study involving 40 healthy participants confirmed the dosage form's acceptability, thereby supporting the clinical translatability of this simple yet effective platform technology.

Beyond traditional therapy: Mucoadhesive polymers as a new frontier in oral cancer management

In recent times mucoadhesive drug delivery systems are gaining popularity in oral cancer. It is a malignancy with high global prevalence. Despite significant advances in cancer therapeutics, improving the prognosis of late-stage oral cancer remains challenging. Targeted therapy using mucoadhesive polymers can improve oral cancer patients' overall outcome by offering enhanced oral mucosa bioavailability, better drug distribution and tissue targeting, and minimizing systemic side effects. Mucoadhesive polymers can also be delivered via different formulations such as tablets, films, patches, gels, and nanoparticles. These polymers can deliver an array of medicines, making them an adaptable drug delivery approach. Drug delivery techniques based on these mucoadhesive polymers are gaining traction and have immense potential as a prospective treatment for late-stage oral cancer. This review examines leading research in mucoadhesive polymers and discusses their potential applications in treating oral cancer.

Nanotechnology-based mucoadhesive and mucus-penetrating drug-delivery systems for transbuccal drug delivery

Buccal drug-delivery systems present a promising approach for the drug delivery to the buccal mucosa, addressing oral cavity-specific problems, enabling systemic delivery and minimizing adverse effects on biological systems. Numerous strategies have been proposed to load drug-containing nanoparticles (NPs) to the buccal mucosa for local and systemic applications. There has been considerable interest in the development of mucoadhesive buccal formulations, particularly hydrogel composites utilizing mucoadhesive films incorporating NPs. Drug permeability and controlled drug release through buccal drug delivery continues to pose a challenge despite the availability of various remedies. This review highlights the need for, mechanisms and latest advances in NP-based transbuccal drug delivery with a focus on various pathological disorders and examples and limitations of the different methods.

Personalizing oral delivery of nanoformed piroxicam by semi-solid extrusion 3D printing

Semi-solid extrusion (SSE) 3D printing enables flexible designs and dose sizes to be printed on demand and is a suitable tool for fabricating personalized dosage forms. Controlled Expansion of Supercritical Solution (CESS®) is a particle size reduction technology, and it produces particles of a pure active pharmaceutical ingredient (API) in a dry state, suspendable in the printing ink. In the current study, as a model API of poorly water-soluble drug, nanoformed piroxicam (nanoPRX) prepared by CESS® was accommodated in hydroxypropyl methylcellulose- or hydroxypropyl cellulose-based ink formulations to warrant the printability in SSE 3D printing. Importantly, care must be taken when developing nanoPRX formulations to avoid changes in their polymorphic form or particle size. Printing inks suitable for SSE 3D printing that successfully stabilized the nanoPRX were developed. The inks were printed into films with escalating doses with exceptional accuracy. The original polymorphic form of nanoPRX in the prepared dosage forms was not affected by the manufacturing process. In addition, the conducted stability study showed that the nanoPRX in the prepared dosage form remained stable for at least three months from printing. Overall, the study rationalizes that with nanoparticle-based printing inks, superior dose control for the production of personalized dosage forms of poorly water-soluble drugs at the point-of-care can be achieved.

Interpolymer Complexes Based on Cellulose Ethers: Application

Interpolymer complexes based on cellulose ethers have gained significant interest in recent years due to their versatile applications. These complexes are formed by combining different polymers through non-covalent interactions, resulting in stable structures. This article provides an overview of the various fields where IPCs based on cellulose ethers find application. IPCs based on cellulose ethers show great potential in drug delivery systems. These complexes can encapsulate drugs and enable controlled release, making them suitable for sustained drug delivery. They offer advantages in terms of precise dosage and enhanced therapeutic efficacy. Coatings and adhesives also benefit from IPCs based on cellulose ethers. These complexes can form films with excellent mechanical strength and enhanced water resistance, providing durability and protection. They have applications in various industries where coatings and adhesives play a crucial role. In food packaging, IPCs based on cellulose ethers are highly relevant. These complexes can form films with effective barrier properties against oxygen and water vapor, making them ideal for packaging perishable foods. They help extend to shelf life of food products by minimizing moisture and oxygen transfer. Various methods, such as solvent casting, coacervation, and electrostatic complexation, are employed to synthesize IPCs based on cellulose ethers.

Miconazole Nitrate Microparticles in Lidocaine Loaded Films as a Treatment for Oropharyngeal Candidiasis

Oral candidiasis is an opportunistic infection that affects mainly individuals with weakened immune system. Devices used in the oral area to treat this condition include buccal films, which present advantages over both oral tablets and gels. Since candidiasis causes pain, burning, and itching, the purpose of this work was to develop buccal films loaded with both lidocaine (anesthetic) and miconazole nitrate (MN, antifungal) to treat this pathology topically. MN was loaded in microparticles based on different natural polymers, and then, these microparticles were loaded in hydroxypropyl methylcellulose-gelatin-based films containing lidocaine. All developed films showed adequate adhesiveness and thickness. DSC and XRD tests suggested that the drugs were in an amorphous state in the therapeutic systems. Microparticles based on chitosan-alginate showed the highest MN encapsulation. Among the films, those containing the mentioned microparticles presented the highest tensile strength and the lowest elongation at break, possibly due to the strong interactions between both polymers. These films allowed a fast release of lidocaine and a controlled release of MN. Due to the latter, these systems showed antifungal activity for 24 h. Therefore, the treatment of oropharyngeal candidiasis with these films could reduce the number of daily applications with respect to conventional treatments.

Triamcinolone acetonide release modelling from novel bilayer mucoadhesive films: an in vitro study

OBJECTIVES

Recurrent aphthous stomatitis (RAS) is a painful disorder that commonly appears as ulcers on the oral mucosa, lasting ∼two weeks (minor) to months (major and herpetiform). Current treatment often necessitates the use of topical steroids in the form of pastes, mouthwashes, or gels, but these forms are often ineffective due to inadequate drug contact time with the ulcers. In this study, the performance of novel bilayer mucoadhesive buccal films loaded with triamcinolone acetonide (TA) has been evaluated for targeted drug delivery.

METHODS

Experimental mucoadhesive films of hydroxypropyl methylcellulose (HPMC), polyvinyl alcohol (PVA), and polyvinyl pyrrolidone (PVP) were prepared by the solvent casting method, and ethyl cellulose (EC) was applied as the backing layer. The films were characterized for their physical properties, including swelling index (SI), folding endurance, adhesion force with porcine buccal mucosa, residence time and in-vitro drug release.

RESULTS

The data showed that the films were flexible with folding endurance> 300 times. With porcine buccal mucosa i) suitable adhesion forces were obtained (between 2.72 and 4.03 N), ii) residence times of> 24 h, and iii) surface pH between 6.8 and 7.1 indicating they would be non-irritant. All films released 100% TA over 6 h, but with varying profiles. The release of TA (over 6 h) from PVP-free films followed Fickian diffusion kinetics (diffusion-controlled release of drug), whereas the mechanism of release from PVP-containing films was found to be a superposition of diffusion-controlled and erosion-controlled release (anomalous).

SIGNIFICANCE

The developed films hold great promise for potentially treating RAS and other oral conditions.

Evaluation of photodynamic therapy on nanoparticles and films loaded-nanoparticles based on chitosan/alginate for curcumin delivery in oral biofilms

Nanoparticles and nanoparticle-loaded films based on chitosan/sodium alginate with curcumin (CUR) are promising strategies to improve the efficacy of antimicrobial photodynamic therapy (aPDT) for the treatment of oral biofilms. This work aimed to develop and evaluate the nanoparticles based on chitosan and sodium alginate encapsulated with CUR dispersed in polymeric films associated with aPDT in oral biofilms. The NPs were obtained by polyelectrolytic complexation, and the films were prepared by solvent evaporation. The photodynamic effect was evaluated by counting Colony Forming Units (CFU/mL). Both systems showed adequate characterization parameters for CUR release. Nanoparticles controlled the release of CUR for a longer period than the nanoparticle-loaded films in simulated saliva media. Control and CUR-loaded nanoparticles showed a significant reduction of 3 log10 CFU/mL against S. mutans biofilms, compared to treatment without light. However, biofilms of S. mutans showed no photoinactivation effect using films loaded with nanoparticles even in the presence of light. These results demonstrate the potential of chitosan/sodium alginate nanoparticles associated with aPDT as carriers for the oral delivery of CUR, offering new possibilities to improve the treatment of dental caries and infections. This work will contribute to advances in the search for innovative delivery systems in dentistry.

Films composed of white angico gum and chitosan containing chlorhexidine as an antimicrobial agent

Anadenanthera colubrina, popularly known as white angico, is a species extensively cultivated in Brazil, mainly in the cerrado region, including the state of Piauí. This study examines the development of films composed of white angico gum (WAG) and chitosan (CHI) and containing chlorhexidine (CHX), an antimicrobial agent. The solvent casting method was used to prepare films. Different combinations and concentrations of WAG and CHI were used to obtain films with good physicochemical characteristics. Properties such as the in vitro swelling ratio, the disintegration time, folding endurance, and the drug content were determined. The selected formulations were characterised by scanning electron microscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and X-ray diffraction, and the CHX release time and antimicrobial activity were evaluated. CHX showed a homogenous distribution in all CHI/WAG film formulations. The optimised films showed good physicochemical properties with 80% CHX release over 26 h, which is considered promising for local treatment of severe lesions in the mouth. Cytotoxicity tests of the films did not show toxicity. The antimicrobial and antifungal effects were very effective against the tested microorganisms.

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.

Incorporating sodium deoxycholate endorsed the buccal administration of avanafil to heighten the bioavailability and duration of action

The highly effective phosphodiesterase type 5 inhibitor (avanafil; AVA) is routinely prescribed to treat erectile dysfunction. The drug has poor oral bioavailability and undergoes a significant first-pass metabolism. Therefore, altering AVA's solubility and choosing a different delivery method may boost its effectiveness. Nine different solid dispersion formulations utilizing polyvinylpyrrolidone (PVP) at three different ratios were prepared and characterized. The Box-Behnken design was employed to optimize AVA-buccal tablets. The pre-compression and post-compression characteristics of the tablets were assessed. The mucoadhesion strength of the optimized tablet was investigated using cow buccal mucosal tissue. In vivo performance of the optimized tablets was examined on human volunteers compared to the commercial tablets. PVP K90 at 2:1 drug to polymer ratio showed the highest solubilization capacity. The mucoadhesive polymer type and percentage and the mucopenetration enhancer percentage were significantly affect the mucoadhesion strength, tablet hardness, and the initial and cumulative AVA released from the prepared tablets. The optimized AVA-buccal tablet showed 4.96 folds increase in the mean residence time, higher plasma exposure, and an improvement in the relative bioavailability of AVA by 1076.27% compared with the commercial tablet. Therefore, a successful approach to deal with AVA first-pass metabolism and low bioavailability could be to employ buccal tablets containing a solubility-enhanced form of AVA.

3D printing of a controlled urea delivery device for the prevention of tooth decay

Dental caries is one of the most widespread chronic infectious diseases in the world. It is mainly caused by the production of acid in the biofilm from the bacterial metabolism of carbohydrates. Nowadays, the prevention of caries is mainly based on the use of topical formulations containing fluoride. However, effective fluoride supplementation may not be sufficient in high-risk individuals, leading to the exploration of alternative strategies such as the neutralization of acid in the oral cavity. Urea is hydrolyzed into ammonia by oral bacteria, leading to a local alkalization that may counteract tooth decay. Herein, we report the fabrication of 3D printed personalized dental trays with a local and prolonged release of urea. Composite filaments with tunable urea release kinetics were produced by hot melt extrusion of poly(ε-caprolactone) and poly(vinyl alcohol) or poly(ethylene glycol) blends mixed with urea. The filaments were further used to 3D print by fused deposition modeling objects capable of releasing urea in a sustained and spatially controlled manner. In vitro studies performed in the presence of Streptococcus salivarius demonstrated the ability of urea released from a 3D printed model toothguards to reduce the pH drop induced by carbohydrates. This study showed the potential of urea-loaded devices to reduce cariogenic acidification of the environment surrounding the enamel by delivering urea directly to the tooth surface.

Application of Box-Behnken Design in the Preparation, Optimization, and In-Vivo Pharmacokinetic Evaluation of Oral Tadalafil-Loaded Niosomal Film

Benign prostatic hyperplasia (BPH) affects about 90% of men whose ages are over 65. Tadalafil, a selective PDE-5 inhibitor, was approved by FDA for BPH, however, its poor aqueous solubility and bioavailability are considered major drawbacks. This work intended to develop and evaluate oral fast dissolving film containing tadalafil-loaded niosomes for those who cannot receive the oral dosage form. Niosomes were statistically optimized by Box-Behnken experimental design and loaded into a polymeric oral film. Niosomes were assessed for their vesicular size, uniformity, and zeta potential. The thickness, content uniformity, folding endurance, tensile strength, disintegration time, and surface morphology were evaluated for the prepared polymeric film. The optimized niosomes revealed high entrapment efficiency (99.78 ± 2.132%) and the film was smooth with good flexibility and convenient thickness (110 ± 10 µm). A fast release of tadalafil was achieved within 5 min significantly faster than the niosomes-free drug film. The in-vivo bioavailability in rats established that the optimized niosomal film enhanced tadalafil systemic absorption, with higher peak concentration (Cmax = 0.63 ± 0.03 µg/mL), shorter Tmax value (0.66-fold), and relative bioavailability of 118.4% compared to the marketed tablet. These results propose that the oral film of tadalafil-loaded niosomes is a suitable therapeutic application that can be passed with ease to geriatric patients who suffer from BPH.

Fabrication and characterization of orodispersible films loaded with solid dispersion to enhance Rosuvastatin calcium bioavailability

The present study was aimed to formulate and evaluate fast dissolving oral film of Rosuvastatin calcium to improve its bioavailability in comparison to typical solid oral dosage forms. The drug was formulated as solid dispersion with hydrophilic polymers and assessed for different constraints such as drug content, saturated solubility, and drug-polymer interaction. Best formula was selected and prepared in the form of orodispersible film. The films were developed by solvent casting method and examined for weight variations, drug content, folding endurance, pH, swelling profile, disintegration time, and in vitro dissolution. Further pharmacokinetic study was also performed on rabbit and compared with that of the marketed oral formulation. The drug and the polymers were found to be compatible with each other by FTIR study. Maximum solubility was found at drug polymer ratio of 1:4 and that was 54.53 ± 2.05 µg/mL. The disintegration time of the developed film was observed to be 10 ± 2.01 s, while release of the Rosuvastatin from the film was found to be 99.06 ± 0.40 in 10 min. Stability study shown that developed film was stable for three months. Further pharmacokinetic study revealed that developed orodispersible film had enhance oral bioavailability as compared to marketed product (Crestor® tablets). Conclusively, the study backs the development of a viable ODF of Rosuvastatin with better bioavailability.

A novel nanotechnological mucoadhesive and fast-dissolving film for vaginal delivery of clotrimazole: design, characterization, and in vitro antifungal action

Pullulan (PUL) films containing pomegranate seed oil and Eudragit^® RS100 nanocapsules loaded with clotrimazole (CTZ-NC-PUL) were developed to treat vulvovaginal candidiasis (VVC). Our findings showed that the nanocapsule average diameter was around 163 ± 4 nm, with polydispersity index values of up to 0.1 ± 0.01 and positively charged zeta potential (+ 43.5 ± 0.7 mV). The pH was in the acid range (5.14 ± 0.12) and encapsulation efficiency was around 99.6%; CTZ nanoencapsulation promoted higher homogeneity values for the film (91%), and the stability studies displayed no changes in the drug content after 120 days for the CTZ-NC-PUL under refrigerated conditions. All formulations were considered non-irritant, and CTZ-NC-PUL promoted a controlled release of the drug (60% in 24 h) compared to CTZ-PUL (100% in 8 h). The permeation results corroborate the drug release, where higher CTZ amounts were found in the mucosa and receptor medium for CTZ-PUL (21.02 and 4.46 μg/cm²). The films were fast dissolving (10 min), and CTZ-NC-PUL presented higher mucoadhesive properties; the antifungal activity against Candida albicans was maintained, and the in vitro efficacy of the film was proved. In conclusion, CTZ-NC-PUL formulation was considered promising and suitable for vaginal application against candida-related infections.

Buccal films: A review of therapeutic opportunities, formulations & relevant evaluation approaches

The potential of the mucoadhesive film technology is hard to ignore, owing to perceived superior patient acceptability versus buccal tablets, and significant therapeutic opportunities compared to conventional oral drug delivery systems, especially for those who suffer from dysphagia. In spite of this, current translation from published literature into the commercial marketplace is virtually non-existent, with no authorised mucoadhesive buccal films available in the UK and very few available in the USA. This review seeks to provide an overview of the mucoadhesive buccal film technology and identify key areas upon which to focus scientific efforts to facilitate the wider adoption of this patient-centric dosage form. Several indications and opportunities for development were identified, while discussing the patient-related factors influencing the use of these dosage forms. In addition, an overview of the technologies behind the manufacturing of these films was provided, highlighting manufacturing methods like solvent casting, hot melt extrusion, inkjet printing and three-dimensional printing. Over thirty mucoadhesive polymers were identified as being used in film formulations, with details surrounding their mucoadhesive capabilities as well as their inclusion alongside other key formulation constituents provided. Lastly, the importance of physiologically relevant in vitro evaluation methodologies was emphasised, which seek to improve in vivo correlations, potentially leading to better translation of mucoadhesive buccal films from the literature into the commercial marketplace.

Characterization of an In Vitro/Ex Vivo Mucoadhesiveness Measurement Method of PVA Films

Transmucosal drug delivery systems can be an attractive alternative to conventional oral dosage forms such as tablets. There are numerous in vitro methods to estimate the behavior of mucoadhesive dosage forms in vivo. In this work, a tensile test system was used to measure the mucoadhesion of polyvinyl alcohol films. An in vitro screening of potential influencing variables was performed on biomimetic agar/mucin gels. Among the test device-specific factors, contact time and withdrawal speed were identified as influencing parameters. In addition, influencing factors such as the sample area, which showed a linear relationship in relation to the resulting work, and the liquid addition, which led to an abrupt decrease in adhesion, could be identified. The influence of tissue preparation was investigated in ex vivo experiments on porcine small intestinal tissue. It was found that lower values of F_max and W_ad were obtained on processed and fresh tissue than on processed and thawed tissue. Film adhesion on fresh, unprocessed tissue was lowest in most of the animals tested. Comparison of ex vivo measurements on porcine small intestinal tissue with in vitro measurements on agar/mucin gels illustrates the inter- and intra-individual variability of biological tissue.

Fabrication of Hydroxypropyl Methylcellulose Orodispersible Film Loaded Mirtazapine Using a Syringe Extrusion 3D Printer

Depression is a mental illness causing a continuous negative feeling and loss of interest and affects physical and mental health. Mirtazapine (MTZ) is an effective medicine for treating depression, but patients lack compliance. However, transforming a pharmaceutical dosage form to an orodispersible film (ODF) could resolve this issue. This study aims to fabricate ODF-loading mirtazapine, using a syringe extrusion 3D printer, and compare its properties with the solvent-casting method. The ODFs were prepared by dissolving the mirtazapine in a hydroxypropyl methylcellulose E15 solution, and then fabricated by a 3D printer or casting. The 3D printing was accurate and precise in fabricating the ODFs. The SEM micrographs showed that the mirtazapine-printed ODF (3D-MTZ) was porous, with crystals of mirtazapine on the film’s surface. The 3D-MTZ exhibited better mechanical properties than the mirtazapine-casted ODF (C-MTZ), due to the 3D-printing process. The disintegration time of the 3D-MTZ in a simulated salivary fluid, pH 6.8 at 37 °C, was 24.38 s, which is faster than the C-MTZ (46.75 s). The in vitro dissolution study, in 0.1 N HCl at 37 °C, found the 3D-MTZ quickly released the drug by more than 80% in 5 min. This study manifested that 3D-printing technology can potentially be applied for the fabrication of ODF-containing mirtazapine.

Patches as Polymeric Systems for Improved Delivery of Topical Corticosteroids: Advances and Future Perspectives

Mucoadhesive polymer patches are a promising alternative for prolonged and controlled delivery of topical corticosteroids (CS) to improve their biopharmaceutical properties (mainly increasing local bioavailability and reducing systemic toxicity). The main biopharmaceutical advantages of patches compared to traditional oral dosage forms are their excellent bioadhesive properties and their increased drug residence time, modified and unidirectional drug release, improved local bioavailability and safety profile, additional pain receptor protection, and patient friendliness. This review describes the main approaches that can be used for the pharmaceutical R&D of oromucosal patches with improved physicochemical, mechanical, and pharmacological properties. The review mainly focuses on ways to increase the bioadhesion of oromucosal patches and to modify drug release, as well as ways to improve local bioavailability and safety by developing unidirectional -release poly-layer patches. Various techniques for obtaining patches and their influence on the structure and properties of the resulting dosage forms are also presented.

The use of natural gums to produce nano-based hydrogels and films for topical application

Natural gums are a source of biopolymeric materials with a wide range of applications for multiple purposes. These polysaccharides are extensively explored due to their low toxicity, gelling and thickening properties, and bioadhesive potential, which have sparked interest in researchers given their use in producing pharmaceutic dosage forms compared to synthetic agents. Hence, gums can be used as gelling and film-forming agents, which are suitable platforms for topical drug administration. Additionally, recent studies have demonstrated the possibility of obtaining nanocomposite materials formed by a polymeric matrix of gums associated with nanoscale carriers that have shown superior drug delivery performance and compatibility with multiple administration routes compared to starting components. In this sense, research on topical natural gum-based form preparation containing drug-loaded nanocarriers was detailed and discussed herein. A special focus was devoted to the advantages achieved regarding physicochemical and mechanical features, drug delivery capacity, permeability through topical barriers, and biocompatibility of the hydrogels and polymeric films.

Formulation and Development of Bioadhesive Oral Films Containing Usnea barbata (L.) F.H.Wigg Dry Ethanol Extract (F-UBE-HPC) with Antimicrobial and Anticancer Properties for Potential Use in Oral Cancer Complementary Therapy

Medical research explores plant extracts’ properties to obtain potential anticancer drugs. The present study aims to formulate, develop, and characterize the bioadhesive oral films containing Usnea barbata (L.) dry ethanol extract (F-UBE-HPC) and to investigate their anticancer potential for possible use in oral cancer therapy. The physicochemical and morphological properties of the bioadhesive oral films were analyzed through Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Atomic Force Microscopy (AFM), thermogravimetric analysis (TG), and X-ray diffraction techniques. Pharmacotechnical evaluation (consisting of the measurement of the specific parameters: weight uniformity, thickness, folding endurance, tensile strength, elongation, moisture content, pH, disintegration time, swelling rate, and ex vivo mucoadhesion time) completed the bioadhesive films’ analysis. Next, oxidative stress, caspase 3/7 activity, nuclear condensation, lysosomal activity, and DNA synthesis induced by F-UBE-HPC in normal blood cell cultures and oral epithelial squamous cell carcinoma (CLS-354) cell line and its influence on both cell types’ division and proliferation was evaluated. The results reveal that each F-UBE-HPC contains 0.330 mg dry extract with a usnic acid (UA) content of 0.036 mg. The bioadhesive oral films are thin (0.093 ± 0.002 mm), reveal a neutral pH (7.10 ± 0.02), a disintegration time of 118 ± 3.16 s, an ex vivo bioadhesion time of 98 ± 3.58 min, and show a swelling ratio after 6 h of 289 ± 5.82%, being suitable for application on the oral mucosa. They displayed in vitro anticancer activity on CLS-354 tumor cells. By considerably increasing cellular oxidative stress and caspase 3/7 activity, they triggered apoptotic processes in oral cancer cells, inducing high levels of nuclear condensation and lysosomal activity, cell cycle arrest in G0/G1, and blocking DNA synthesis. All these properties lead to considering the UBE-loaded bioadhesive oral films suitable for potential application as a complementary therapy in oral cancer.

Development and In Vitro-Ex Vivo Evaluation of Novel Polymeric Nasal Donepezil Films for Potential Use in Alzheimer's Disease Using Experimental Design

The objective and novelty of the present study is the development and optimization of innovative nasal film of Donepezil hydrochloride (DH) for potential use in Alzheimer’s disease. Hydroxypropyl-methyl-cellulose E50 (factor A) nasal films, with Polyethylene glycol 400 as plasticizer (factor B), and Methyl-β-Cyclodextrin, as permeation enhancer (factor C), were prepared and characterized in vitro and ex vivo. An experimental design was used to determine the effects of the selected factors on permeation profile of DH through rabbit nasal mucosa (response 1), and on film flexibility/foldability (response 2). A face centered central composite design with three levels was applied and 17 experiments were performed in triplicate. The prepared films exhibited good uniformity of DH content (90.0 ± 1.6%−99.8 ± 4.9%) and thickness (19.6 ± 1.9−170.8 ± 11.5 μm), storage stability characteristics, and % residual humidity (<3%), as well as favourable swelling and mucoadhesive properties. Response surface methodology determined the optimum composition for flexible nasal film with maximized DH permeation. All selected factors interacted with each other and the effect of these interactions on responses is strongly related to the factor’s concentration ratios. Based on these encouraging results, in vivo serum and brain pharmacokinetic study of the optimized nasal film, in comparison to DH oral administration, is ongoing in an animal model.

Stability, Permeability and Cytotoxicity of Buccal Films in Allergy Treatment

Oral mucoadhesive systems, such as polymer films, are among innovative pharmaceutical products. These systems can be applied in swallowing problems and can also be used in geriatrics and paediatrics. In our earlier work, we successfully formulated buccal mucoadhesive polymer films, which contained cetirizine-hydrochloride (CTZ) as the API. The present study focused on investigating the stability and permeability of the prepared films. The stability of the films was studied with an accelerated stability test. During the stability test, thickness, breaking hardness and in vitro mucoadhesivity were analysed. Furthermore, the interactions were studied with FT-IR spectroscopy, and the changes in the amount of the API were also monitored. Cytotoxicity and cell line permeability studies were carried out on TR 146 buccal cells. Compositions that can preserve more than 85% of the API after 6 months were found. Most of the compositions had a high cell viability of more than 50%. Citric acid (CA) decreased the stability and reduced every physical parameter of the films. However, cell line studies showed that the permeability of the films was enhanced. In our work, we successfully formulated CTZ-containing buccal films with adequate stability, high cell viability and appropriate absorption properties.

Development and evaluation of bioadhesive buccal films based on sodium alginate for allergy therapy

Buccal drug administration is a less explored area, therefore researchers and companies focus on its research because of its innovative potential and opportunities. Buccal polymer films (patches) are considered to be an innovative form and have a great number of advantageous properties. Firstly, patients who suffer from swallowing problems and children can also apply them. The active pharmaceutical ingredient enters the systemic circulation directly without degradation and transformation. The aim of this study was to formulate buccal films with sodium alginate (SA) because it is a rarely used, innovative polymer for the formulation of buccal films. The mechanical, chemical properties and dosage forms of the prepared films were investigated with different methods. To formulate the films, cetirizine dihydrochloride (CTZ) was used as model drug, and glycerol (GLY) was added to make the films more elastic. The samples were prepared and stored at room temperature. As a result, it can be seen that the mechanical properties of all film compositions show good results, especially breaking hardness. The films with high SA concentration containing CTZ had appropriate mucoadhesion forces, so these samples are suitable for application on the buccal mucosa. The results of dissolution confirmed this finding. Finally, it can be said we formulated fast dissolving films and it can be concluded that the films prepared with 3% SA concentration containing 1% and 3% GLY can be recommended for buccal application.

Incorporation of Ethylcellulose Microparticles Containing a Model Drug with a Bitter Taste into Nanofibrous Mats by the Electrospinning Technique—Preliminary Studies

Electrospinning is considered a simple and comprehensive technique to formulate ultrafine fibres by using an electric field. Polymeric nanofibers constitute promising materials in biomedical applications as drug delivery systems. For their preparation, both natural and synthetic polymers are utilised. Owing to the potential use of electrospun nanofibers as an orodispersible drug dosage form, ethylcellulose microparticles containing the antihistamine drug rupatadine fumarate, prepared by the spray drying technique to conceal the drug’s bitter taste, were incorporated into nanofibers. The obtained nanofibrous mats were evaluated for morphology, mechanical strength, disintegration time, the drug solid state and acceptability in terms of taste masking efficiency. Preliminary studies showed that hypromellose used as a single polymer was not a suitable substance for the manufacturing of nanofibers. Therefore, in order to facilitate the obtention of homogeneous nonwovens, different grades of polyethylene oxide (2,000,000–2M-Da and 4,000,000–4M-Da) were added, which improved the quality of the prepared mats. Nanofibers of the most satisfactory quality were obtained from hypromellose (6.5% w/v) and PEO (2M, 0.5% w/v). SEM image analysis has shown that the nanofibers were homogeneous and smooth and possessed a fast disintegration time (below 30 s) and an adequate drug content with a simultaneous taste-masking effect (as indicated by the in vivo and in vitro methods). However, further studies are necessary to refine their mechanical characteristics.

Optimization of Multilayer Films Composed of Chitosan and Low-Methoxy Amidated Pectin as Multifunctional Biomaterials for Drug Delivery

Polyelectrolyte multilayers (PEMs) based on polyelectrolyte complex (PEC) structures are recognized as interesting materials for manufacturing functionalized coatings or drug delivery platforms. Difficulties in homogeneous PEC system development generated the idea of chitosan (CS)/low-methoxy amidated pectin (LM PC) multilayer film optimization with regard to the selected variables: the polymer ratio, PC type, and order of polymer mixing. Films were formulated by solvent casting method and then tested to characterize CS/LM PC PECs, using thermal analysis, Fourier transform infrared spectroscopy (FTIR), turbidity, and zeta potential measurements. The internal structure of the films was visualized by using scanning electron microscopy. Analysis of the mechanical and swelling properties enabled us to select the most promising formulations with high uniformity and mechanical strength. Films with confirmed multilayer architecture were indicated as a promising material for the multifunctional systems development for buccal drug delivery. They were also characterized by improved thermal stability as compared to the single polymers and their physical mixtures, most probably as a result of the CS–LM PC interactions. This also might indicate the potential protective effect on the active substances being incorporated in the PEC-based films.

Induction of protein specific antibody by carbonated hydroxy apatite as a candidate for mucosal vaccine adjuvant

Buccal mucosae are considered as a site for vaccine delivery since they are relatively abundant with antigen-presenting dendritic cells, mainly Langerhans cells. In this study, we formulated carbonated hydroxy apatite (CHA) with ovalbumin (OVA) (denoted as CHA-OVA), incorporated it into bilayer buccal membrane to form hydrogel films containing CHA-OVA complex for vaccination via buccal mucosae. Ethylcellulose blend with polyethylene glycol 400 were used as impermeable backing layer. Physical properties of all tested buccal membranes were found suitable for mucosal application. In vitro and ex vivo release study showed there was no burst release of OVA found from all tested formula. From the in vivo examination, rabbit buccal mucosae vaccinated by mucoadhesive membranes containing CHA-OVA complex demonstrated mucosal specific antibody induction, represented the potential of CHA as a candidate of needle-free vaccine adjuvant. Future research is awaiting to investigate proper CHA crystallinity in complex with protein against targeted diseases.

Formulation and Characterization of Nicotine Microemulsion-Loaded Fast-Dissolving Films for Smoking Cessation

The present study aimed to develop a nicotine microemulsion (NCT-ME) and incorporate it into a fast-dissolving film. The NCT-ME was prepared by mixing the specified proportions of nicotine (NCT), surfactant, co-solvent, and water. The NCT-ME was measured by its average droplet size, size distribution, zeta potential, and morphology. NCT-ME fast-dissolving films were prepared by the solvent casting technique. The films were characterized by morphology, weight, thickness, disintegration time, and mechanical strength properties and the determined NCT loading efficiency and in vitro drug release. The results showed that almost all NCT-MEs presented droplet sizes of less than 100 nm with a spherical form, narrow size distribution, and zeta potentials of −10.6 to −73.7 mV. There was no difference in weight and thickness between all NCT-ME films, but significant changes in the disintegration times were noticed in NCT40-Smix[PEG-40H(2:1)]10 film. The mechanical properties of films varied with changes in type of surfactant. About 80% of the drug release was observed to be between 3 and 30 min. The drug release kinetics were fitted with the Higuchi matrix model. The NCT40-Smix[P-80(1:1)]10 film showed the highest dissolution rate. It was concluded that the developed ME-loaded fast-dissolving film can increase drug release to a greater extent than the films without ME.

Orodispersible Films with Rupatadine Fumarate Enclosed in Ethylcellulose Microparticles as Drug Delivery Platform with Taste-Masking Effect

Orally disintegrating (orodispersible) films provide a versatile tool for drug administration, especially in the pediatric and geriatric population, since they reduce the risk of choking and do not necessitate drinking water during application. By considering their direct contact with the taste buds, palatability is an influential aspect related to patient compliance. The microparticles based on taste-masking polymers containing drugs enclosed inside effectively mask the unpleasant taste of medicines. Ethylcellulose is a hydrophobic polymer widely used as a taste-masking material. Rupatadine fumarate, a second-generation antihistamine drug, is characterised by an intense bitter taste; therefore, it is crucial to achieve a tolerable taste whilst developing orodispersible formulations with its content. The objective of this study was to develop orally disintegrating films with rupatadine fumarate in the form of ethylcellulose-based microparticles obtained from aqueous dispersions of ethylcellulose—Surelease^® or Aquacoat^® ECD. It was a technological challenge to achieve homogenous drug content per dosage unit and sufficient mechanical properties for film operating due to the necessity to suspend the microparticles in the casting solution. Although the process of obtaining films consisted of several steps (mixing, pouring, drying), the particles were homogeneously dispersed, and each film of the desired size contained the proper dose of the drug. The taste-masking effect was also maintained. This parameter was confirmed by three independent methods: in vivo by healthy volunteers, an electronic tongue and a dissolution test. The applied taste-evaluation techniques showed that the films containing Aquacoat^® ECD microparticles have the highest degree of bitter taste reduction, which confirms the results obtained in our previous studies.