Comparative study on disintegration methods for oral film preparations

Development of an innovative eugenol and borax-based orodispersible film for enhanced treatment of mouth ulcers

Orodispersible films (ODFs) have emerged as an advanced and patient-friendly delivery system due to ease of administration, improved patient compliance, quick release and taste-masking of active pharmaceutical ingredients. This research reports the preparation of the ODF containing eugenol and borax (EB-ODF) by a solvent casting technique for treating mouth ulcers. The EB-ODF consisted of vinyl pyrrolidone/vinyl acetate copolymer (Kollidon® VA64, VA64) and hydroxypropyl methylcellulose (HPMC-K250) as the film formers where eugenol and borax were loaded. The thickness of the EB-ODF obtained was 0.119 ± 0.001 mm and the tensile strength was 13.1 ± 1.1 N/mm2 (p > 0.05). The prepared films disintegrated in the oral cavity within 30 s and over 90% of the eugenol was released from the film in the first 5 min. Furthermore, the combined application of eugenol and borax, loaded in EB-ODF, displayed notable synergetic antibacterial property against both gram-negative and gram-positive bacteria. In an in-vivo study on a rat model with chemical burn-induced oral ulcers, the EB-ODF treatment group had a 100% reduction in ulcer area (p > 0.05) after 10 days of treatment and demonstrated a 38.7% higher reduction in oral ulcer area compared to the Dingpeng Cream treatment group (p < 0.0001). The EB-ODF treatment group showed minimal oral irritation, scoring only 1 point and a 65% preference in the taste tests (p < 0.0001). In summary, EB-ODF had successfully overcome the poor palatability of commercially available formulation and provided notable potential for further ulcer treatment product development.

Development and effect of orodispersible film incorporated with Biosilicate for remineralization of dental enamel subjected to cariogenic and erosive challenge

OBJECTIVES

The objective of this in vitro study was to assess the efficiency of incorporating Biosilicate particles (30 and 50 mg) into an experimental orodispersible film and its efficacy in the remineralization process of bovine dental enamel under cariogenic and erosive challenges.

METHODS

Ninety-nine intact incisors, devoid of cracks or fractures, yielding 198 samples (6 × 6 × 2 mm) via vestibular sectioning using a low-speed diamond disc under water cooling. After flattening the enamel surface with 600, 1200, and 2000 grit sandpaper, the samples were divided into two groups based on the challenges they underwent: cariogenic (0.1 M lactic acid at pH 5.0) or erosive (0.05 M citric acid solution at pH 2.3). Samples from each challenge were further categorized into 11 groups (n = 9) according to the duration of cariogenic (3, 7, and 14 days) or erosive (3, 7, and 10 days) challenge, along with positive control groups (fragments untreated with challenges and treated with different Biosilicate concentrations) and negative controls (fragments treated with artificial saliva for the same periods established for cariogenic and erosive challenges). Treatments with orodispersible films containing Biosilicate (30 and 50 mg) were administered for 2 min per day for 15 days.

RESULTS

The highest remineralizing potential was observed in samples treated with Biosilicate after 14 days of cariogenic challenge, irrespective of the concentration tested. For samples subjected to erosive challenge, erosion time did not affect Biosilicate's remineralizing potential.

CONCLUSION

Biosilicate shows promise in terms of remineralizing potential in enamel subjected to cariogenic challenge due to its ability to form hydroxycarbonapatite in mineralized tissues.

Assessment of Alginate Gel Films as the Orodispersible Dosage Form for Meloxicam

The aim of this study was to obtain films based on sodium alginate (SA) for disintegration in the oral cavity. The films were prepared with a solvent-casting method, and meloxicam (MLX) as the active ingredient was suspended in a 3% sodium alginate solution. Two different solid-dosage-form additives containing different disintegrating agents, i.e., VIVAPUR 112® (MCC; JRS Pharma, Rosenberg, Germany) and Prosolve EASYtabs SP® (MIX; JRS Pharma, Rosenberg, Germany), were used, and four different combinations of drying time and temperature were tested. The influence of the used disintegrant on the properties of the ODFs (orodispersible films) was investigated. The obtained films were studied for their appearance, elasticity, mass uniformity, water content, meloxicam content and, finally, disintegration time, which was studied using two different methods. The films obtained with the solvent-casting method were flexible and homogeneous in terms of MLX content. Elasticity was slightly better when MIX was used as a disintegrating agent. However, these samples also revealed worse uniformity and mechanical durability. It was concluded that the best properties of the films were achieved using the mildest drying conditions. The type of the disintegrating agent had no effect on the amount of water remaining in the film after drying. The water content depended on the drying conditions. The disintegration time was not affected by the disintegrant type, but some differences were observed when various drying conditions were applied. However, regardless of the formulation type and manufacturing conditions, the analyzed films could not be classified as fast disintegrating films, as the disintegration time exceeded 30 s in all of the tested formulations.

Formulation of Saxagliptin Oral Films: Optimization, Physicochemical Characterization, In-Vivo Assessment, and In-Vitro Real-Time Release Monitoring via a Novel Polyaniline Nanoparticles-Based Solid-Contact Screen Printed Ion-Selective Electrode

Oral dispersible films have received broad interest due to fast drug absorption and no first-path metabolism, leading to high bioavailability and better patient compliance. Saxagliptin (SXG) is an antidiabetic drug that undergoes first-path metabolism, resulting in a less active metabolite, so the development of SXG oral dispersible films (SXG-ODFs) improves SXG bioavailability. The formula optimisation included a response surface experimental design and the impact of three formulation factors, the type and concentration of polymer and plasticiser concentration on in-vitro disintegration time and folding endurance. Two optimised SXG-ODFs prepared using either polyvinyl alcohol (PVA) or hydroxypropyl methylcellulose were investigated. SXG-ODFs prepared with PVA demonstrated a superior rapid disintegration time, ranging from 17 to 890 s, with the fastest disintegration time recorded at 17 s. These short durations can be attributed to the hydrophilic nature of PVA, facilitating rapid hydration and disintegration upon contact with saliva. Additionally, PVA-based films displayed remarkable folding endurance, surpassing 200 folds without rupture, indicating flexibility and stability. The high tensile strength of PVA-based films further underscores their robust mechanical properties, with tensile strength values reaching up to 4.53 MPa. SXG exhibits a UV absorption wavelength of around 212 nm, posing challenges for traditional quantitative spectrophotometric analysis, so a polyaniline nanoparticles-based solid-contact screen-printed ion-selective electrode (SP-ISE) was employed for the determination of SXG release profile effectively in comparison to HPLC. SP-ISE showed a better real-time release profile of SXG-ODFs, and the optimised formula showed lower blood glucose levels than commercial tablets.

Investigating Bioactive-Glass-Infused Gels for Enamel Remineralization: An In Vitro Study

OBJECTIVE

Dental hypersensitivity remains widespread, underscoring the need for materials that can effectively seal dental tubules. This study evaluated the potential of bioactive-glass-infused hydroxyethyl cellulose gels in this context.

METHODS

Five gels were synthesized, each containing 20% bioactive glass (specifically, 45S5, S53P4, Biomin F, and Biomin C), with an additional blank gel serving as a control. Subjected to two months of accelerated aging at 37 ± 2 °C, these gels were assessed for key properties: viscosity, water disintegration time, pH level, consistency, adhesion to glass, and element release capability.

RESULTS

Across the board, the gels facilitated the release of calcium, phosphate, and silicon ions, raising the pH from 9.00 ± 0.10 to 9.7 ± 0.0-a range conducive to remineralization. Dissolution in water occurred within 30-50 min post-application. Viscosity readings showed variability, with 45S5 reaching 6337 ± 24 mPa/s and Biomin F at 3269 ± 18 mPa/s after two months. Initial adhesion for the blank gel was measured at 0.27 ± 0.04 Pa, increasing to 0.73 ± 0.06 Pa for the others over time. Gels can release elements upon contact with water (Ca- Biomin C 104.8 ± 15.7 mg/L; Na- Biomin F 76.30 ± 11.44 mg/L; P- Biomin C 2.623 ± 0.393 mg/L; Si- 45S5-45.15 ± 6.77mg/L, F- Biomin F- 3.256 ± 0.651mg/L; Cl- Biomin C 135.5 ± 20.3 mg/L after 45 min).

CONCLUSIONS

These findings highlight the gels' capacity to kickstart the remineralization process by delivering critical ions needed for enamel layer reconstruction. Further exploration in more dynamic, real-world conditions is recommended to fully ascertain their practical utility.

Customizable orodispersible films: Inkjet printing and data matrix encoding for personalized hydrocortisone dosing

The aim of this study was to exploit the versatility of inkjet printing to develop flexible doses of drug-loaded orodispersible films that encoded information in a data matrix pattern, and to introduce a specialised data matrix-generator software specifically focused on the healthcare sector. Pharma-inks (drug-loaded inks) containing hydrocortisone (HC) were developed and characterised based on their rheological properties and drug content. Different strategies were investigated to improve HC solubility: formation of β-cyclodextrin complexes, Soluplus® based micelles, and the use of co-solvent systems. The software automatically adapted the data matrix size and identified the number of layers for printing. HC content deposited in each film layer was measured, and it was found that the proportion of co-solvent used directly affected the drug solubility and simultaneously played a role in the modification of the viscosity and surface tension of the inks. The formation of β-cyclodextrin complexes improved the drug quantity deposited in each layer. On the contrary, micelle-based inks were not suitable for printing. Orodispersible films containing flexible and low doses of personalised HC were successfully prepared, and the development of a code generator software oriented to medical use provided an additional, innovative, and revolutionary advantage to personalised medicine safety and accessibility.

Reducing Temperature of Fused Deposition Modelling 3D Printing for Linalool Fast Dissolving Oral Films by Increasing Printer Nozzle Diameter

Oral thrush and throat infections can occur in a wide range of patients. Treatments are available; however, resistance to drugs is a major problem for treating oral and throat infections. Three-dimensional printing (3DP) of fast dissolving oral films (FDFs) of linalool oil may provide an alternative solution. Linalool oil FDFs were printed by fused deposition modelling across 1-18 % w/w linalool content range with nozzle diameters of 0.4 or 1 mm at the temperature range of 150 °C-185 °C. The FDFs were evaluated for physicochemical and mechanical properties. Increasing the printer nozzle diameter to 1 mm allowed reducing the printing temperature from 185 °C to 150 °C; consequently, more linalool was quantified in the films with improved content uniformity. The higher linalool content in the films increased the film disintegration time and mechanical strength. FDFs containing 10% w/w linalool showed clear antifungal activity against Candida albicans. Raman spectroscopy suggested linalool separation from excipients at higher temperature printing. Viscoelastic measurements indicated that to achieve printing; the elastic modulus of molten filament needed to be higher than the loss modulus at low angular frequencies. In conclusion, increasing the printing nozzle diameter may avoid loss of the active ingredient by reducing the temperature of the 3DP process.

Optimizing the fabrication of electrospun nanofibers of prochlorperazine for enhanced dissolution and permeation properties

Despite being an approved antiemetic for more than five decades, the clinical usefulness of prochlorperazine is limited by its low solubility and inconsistent absorption in the gastrointestinal tract, which presents challenges for nanotherapeutic interventions. Here, we report the preparation of a highly soluble and permeable nanofiber formulation of prochlorperazine using the Quality-by-Design approach. The final nanofiber formulation with drug entrapment of 88.02 ± 1.14 % was obtained at 20.0 kV, with a flow rate of 0.5 ml/h and tip-to-collector distance of 19.9 cm. Physio-mechanical properties, such as thickness (0.42 ± 0.02 mm), pH resistance (7.04 ± 0.08), folding endurance (54 ± 5), and tensile strength (0.244 ± 0.02 N.mm-2), were appropriate for packaging and application to oromucosal surfaces. The content uniformity (93.48-106.63 %) and weight variation (<1.8 mg) of the optimal nanofiber formulation were within the permissible limits prescribed for orodispersible films. Microscopical investigations confirm a randomly deposited and dense network of woven nanofibers with an average diameter of 363 ± 5.66 nm. The drug particles were embedded homogeneously on the fiber in the nanoform (4.27 ± 1.34 nm). The spectral analysis using TEM-EDS shows diffraction peaks of sulfur and chlorine, the elemental constituents of prochlorperazine. The drug was amorphized in the nanofiber formulation, as led by the decline of the crystallinity index from 87.25 % to 7.93 % due to electrostatic destabilization and flash evaporation of the solvent. The enthalpy of fusion values of the drug in the nanofiber mat decreased significantly to 23.6 J/g compared to its pristine form, which exhibits a value of 260.7 J/g. The nanofibers were biocompatible with oral mucosal cells, and there were no signs of mucosal irritation compared to 1 % sodium lauryl sulfate. The fiber mats rapidly disintegrated within <1 s and released ≈91.49 ± 2.1 % of the drug within 2 min, almost 2-fold compared to the commercial Stemetil MD® tablets. Similarly, the cumulative amount of the drug permeated across the unit area of the oromucosal membrane was remarkably high (31.28 ± 1.30 μg) compared to 10.17 ± 1.11 μg and 13.10 ± 1.79 μg from the cast film and drug suspension. Our results revealed these nanofiber formulations have the potential to be fast-dissolving oromucosal delivery systems, which can result in enhanced bioavailability with an early onset of action due to rapid disintegration, dissolution, and permeation.

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.

Preparation and Evaluation of Caffeine Orodispersible Films: The Influence of Hydrotropic Substances and Film-Forming Agent Concentration on Film Properties

This study aimed to develop caffeine (CAF) orodispersible films (ODFs) and verify the effects of different percentages of film-forming agent and hydrotropic substances (citric acid-CA or sodium benzoate-SB) on various film properties. Hydroxypropyl methylcellulose E 5 (HPMC E 5) orodispersible films were prepared using the solvent casting method. Four CAF-ODF formulations were prepared and coded as CAF1 (8% HPMC E 5, CAF), CAF2 (8% HPMC E 5 and CAF:CA-1:1), CAF3 (9% HPMC E 5 and CAF:CA-1:1), and CAF4 (9% HPMC E 5 and CAF:SB-1:1). The CAF-ODFs were evaluated in terms of disintegration time, folding endurance, thickness, uniformity of mass, CAF content, thickness-normalized tensile strength, adhesiveness, dissolution, and pH. Thin, opaque, and slightly white CAF-ODFs were obtained. All the formulations developed exhibited disintegration times less than 3 min. The dissolution test revealed that CAF1, CAF2, and CAF3 exhibited concentrations of active pharmaceutical ingredients (APIs) released at 30 min that were close to 100%, whilst CAF4 showed a faster dissolution behaviour (100% of the CAF was released at 5 min). Thin polymeric films containing 10 mg of CAF/surface area (3.14 cm²) were prepared.

Design and development of orally disintegrating films: A platform based on hydroxypropyl methylcellulose and guar gum

From a design of experiments (DOE) performed under four independent variables, with the filmogenicity conditions and shortest disintegration time as the answers, a new oral disintegrating film (ODF) based on hydroxypropyl methylcellulose (HPMC) and guar gum (GG) with the essential oil of Plectranthus amboinicus L. (EOPA) was developed. Sixteen formulations were tested for filmogenicity, homogeneity, and viability. The better selected ODF required 230.1 s for complete disintegration. The retention rate of the EOPA was quantified using the nuclear magnetic resonance hydrogen technique (H¹ NMR), which identified the presence of 0.14 % carvacrol. The scanning electron microscopy showed a smooth and homogeneous surface with the presence of small white dots. Through the disk diffusion test, the EOPA was able to inhibit the growth of clinical strains of the Candida genus and gram-positive and gram-negative bacterial strains. This work opens new perspectives for the development of antimicrobial ODFS used in clinical practice.

Embedding of Poorly Water-Soluble Drugs in Orodispersible Films-Comparison of Five Formulation Strategies

The poor bioavailability of many newly developed active pharmaceutical ingredients (APIs) poses a major challenge in formulation development. To overcome this issue, strategies such as the preparation of amorphous solid dispersions (ASDs), and the application of the APIs in lipid nanocarriers or the wet-milling of the substances into nanoparticles have been introduced. In addition to an efficient formulation strategy, a dosage form that is accepted by all patients is also of great importance. To enable a simple application of the oral dosage form for all patients, orodispersible films (ODFs) are a very promising delivery platform for the APIs because the films directly disintegrate in the mouth. In this study, two poorly water-soluble APIs, fenofibrate and naproxen, were formulated using five different formulation strategies and then embedded in ODFs. It was found that the deliverable amount of API with one ODF highly depends on the formulation strategy as well as the physicochemical properties of the formulated API. The most promising film formulations were ASD-ODFs as well as films with API-loaded lipid nanoemulsions. Both showed a reduction of the dissolution time of the APIs from the ODF compared to an ODF with unformulated API micro particles. In addition, short disintegration times were achieved, although the mechanical film properties were slightly worse compared to the API-free film formulation.

Investigation of Patient-Centric 3D-Printed Orodispersible Films Containing Amorphous Aripiprazole

The objective of this study was to design and evaluate an orodispersible film (ODF) composed of aripiprazole (ARP), prepared using a conventional solvent casting technique, and to fuse a three-dimensional (3D) printing technique with a hot-melt extrusion (HME) filament. Klucel® LF (hydroxypropyl cellulose, HPC) and PE-05JPS® (polyvinyl alcohol, PVA) were used as backbone polymers for 3D printing and solvent casting. HPC-, PVA-, and ARP-loaded filaments were applied for 3D printing using HME. The physicochemical and mechanical properties of the 3D printing filaments and films were optimized based on the composition of the polymers and the processing parameters. The crystalline states of drug and drug-loaded formulations were investigated using differential scanning calorimetry (DSC) and powder X-ray diffraction (XRD). The dissolution and disintegration of the 3D-printed films were faster than those of solvent-cast films. HPC-3D printed film was fully disintegrated within 45 ± 3.5 s. The dissolution rate of HPC films reached 80% within 30 min at pH 1.2 and pH 4.0 USP buffer. There was a difference in the dissolution rate of about 5 to 10% compared to PVA films at the same sampling time. The root mean square of the roughness (Rq) values of each sample were evaluated using atomic force microscopy. The higher the Rq value, the rougher the surface, and the larger the surface area, the more salivary fluid penetrated the film, resulting in faster drug release and disintegration. Specifically, The HPC 3D-printed film showed the highest Rq value (102.868 nm) and average surface roughness (85.007 nm). The puncture strength of 3D-printed films had desirable strength with HPC (0.65 ± 0.27 N/mm2) and PVA (0.93 ± 0.15 N/mm2) to prevent deformation compared to those of marketed film products (over 0.34 N/mm2). In conclusion, combining polymer selection and 3D printing technology could innovatively design ODFs composed of ARP to solve the unmet medical needs of psychiatric patients.

Fabrication and Characterization of Orodispersible Composite Film from Hydroxypropylmethyl Cellulose-Crosslinked Carboxymethyl Rice Starch

Crosslinked carboxymethyl rice starch (CLCMRS), prepared via dual modifications of native rice starch (NRS) with chloroacetic acid and sodium trimetaphosphate, was employed to facilitate the disintegration of hydroxypropylmethylcellulose (HPMC) orodispersible films (ODFs), with or without the addition of glycerol. Fabricated by using the solvent casting method, the composite films, with the HPMC--LCMRS ratios of 9:1, 7:1, 5:1 and 4:1, were then subjected to physicochemical and mechanical evaluations, including weight, thickness, moisture content and moisture absorption, swelling index, transparency, folding endurance, scanning electron microscopy, Fourier transform infrared spectroscopy, tensile strength, elongation at break, and Young’s modulus, as well as the determination of disintegration time by using the Petri dish method (PDM) and slide frame and bead method (SFM). The results showed that HPMC-CLCMRS composite films exhibited good film integrity, uniformity, and transparency with up to 20% CLCMRS incorporation (4:1 ratio). Non-plasticized composite films showed no significant changes in the average weight, thickness, density, folding endurance (96−122), tensile strength (2.01−2.13 MPa) and Young’s modulus (10.28−11.59 MPa) compared to HPMC film (135, 2.24 MPa, 10.67 MPa, respectively). On the other hand, the moisture content and moisture absorption were slightly higher, whereas the elongation at break (EAB; 4.31−5.09%) and the transparency (4.73−6.18) were slightly lowered from that of the HPMC film (6.03% and 7.03%, respectively). With the addition of glycerol as a plasticizer, the average weight and film thickness increased, and the density decreased. The folding endurance was improved (to >300), while the transparency remained in the acceptable range. Although the tensile strength of most composite films decreased (0.66−1.75 MPa), they all exhibited improved flexibility (EAB 7.27−11.07%) while retaining structural integrity. The disintegration times of most composite films (PDM 109−331, SFM 70−214 s) were lower than those of HPMC film (PDM 345, SFM 229 s). In conclusion, the incorporation of CLCMRS significantly improved the disintegration time of the composite films whereas it did not affect or only slightly affected the physicochemical and mechanical characteristics of the films. The 5:1 and 4:1 HPMC:CLCMRS composite films, in particular, showed promising potential application as a film base for the manufacturing of orodispersible film dosage forms.

The impact of the lamination pressure on the properties of electrospinned nanofibrous films

The purpose of this work is to explore the preparation of nanofibrous orally dispersible films (ODFs) by needleless electrospinning from the active pharmaceutical ingredient (API) Tadalafil using particles suspended in a solution of polymers and other excipients. The prepared films were characterized by a combination of scanning electron microscopy, mechanical tests, measurements of the disintegration time and dissolution characteristic, X-ray diffraction, and differential scanning calorimetry. Furthermore, we investigated the impact of lamination pressures in the range of 0 to 5 bars combined with films at various relative humidity values on the mechanical properties of the ODF. An increase in lamination pressure resulted in higher Young's modulus values, with the maximum value observed for a sample laminated at a pressure of 5 bar and the maximum stress and strain of the prepared ODF at a lamination pressure of 1.2 bar. Moreover, there was a significant increase in the disintegration time with increase in lamination pressure. The disintegration time ranged from 0.35 s for non-laminated samples to 12 s for samples laminated at a pressure of 5 bar. On the contrary, the lamination pressure did not reveal to have any impact on the dissolution kinetics. These results confirmed that the lamination pressure can improve the processability of ODFs without affecting the API dissolution kinetics.

Modernising Orodispersible Film Characterisation to Improve Palatability and Acceptability Using a Toolbox of Techniques

Orodispersible films (ODFs) have been widely used in paediatric, geriatric and dysphagic patients due to ease of administration and precise and flexible dose adjustments. ODF fabrication has seen significant advancements with the move towards more technologically advanced production methods. The acceptability of ODFs is dependent upon film composition and process of formation, which affects disintegration, taste, texture and mouthfeel. There is currently a lack of testing to accurately assess ODFs for these important acceptability sensory perceptions. This study produced four ODFs formed of polyvinyl alcohol and sodium carboxymethylcellulose using 3D printing. These were assessed using three in vitro methods: Petri dish and oral cavity model (OCM) methods for disintegration and bio-tribology for disintegration and oral perception. Increasing polymer molecular weight (MW) exponentially increased disintegration time in the Petri dish and OCM methods. Higher MW films adhered to the OCM upper palate. Bio-tribology analysis showed that films of higher MW disintegrated quickest and had lower coefficient of friction, perhaps demonstrating good oral perception but also stickiness, with higher viscosity. These techniques, part of a toolbox, may enable formulators to design, test and reformulate ODFs that both disintegrate rapidly and may be better perceived when consumed, improving overall treatment acceptability.

Concept of Orodispersible or Mucoadhesive “Tandem Films” and Their Pharmaceutical Realization

Orodispersible or mucoadhesive films as a patient-oriented dosage form for low-dosed drugs are usually produced using solvent casting. This paper presents a modification of the solvent casting technique that aimed to divide oral films into two or more compartments. The proposed objectives and fields of applications include improved handling properties and safety of application, the optimization of drug release kinetics and the enhancement of long-term stability when combining two or more active pharmaceutical ingredients into one oral film. A feasibility study for the combination of different film-forming polymers to generate the so-called tandem films was performed. As examples of practical implementation, orodispersible applicator films consisting of a drug-loaded section and a handheld piece were cast, and mucoadhesive buccal tandem films were cast to optimize the dissolution rate of the films.

Orodispersible Films: A Delivery Platform for Solid Lipid Nanoparticles?

To overcome the poor bioavailability observed for many newly developed active pharmaceutical ingredients (APIs), an appropriate formulation strategy is necessary. One approach is the formulation of these substances in solid lipid nanoparticles and their further processing into solid dosage forms. A promising and innovative oral delivery platform could be orodispersible films (ODFs). ODFs were already investigated more closely, e.g., for the administration of API nanoparticles, and proved their suitability for this formulation approach. The current study was aimed at investigating if the HPMC (hydroxypropyl methyl cellulose) film matrix is also suitable to serve as an appropriate delivery platform for solid lipid nanoparticles. Dependent on the type of triglyceride nanoparticles embedded in the film matrix and the formulation of the lipid particles, lipid contents of up to 54 wt.% could be realized in the film matrix without the loss of the nanoparticulate state. Good mechanical properties were confirmed for these films by determining the tensile strength as well as the elongation before breakage. Interestingly, processing of a lipid suspension into this solid dosage form led to a significantly reduced transformation of the lipid particles from the metastable α- into the stable β-polymorph. This could prove very beneficial when the lipid particles are loaded with APIs.

Development of buccal film formulations and their mucoadhesive performance in biomimetic models

When developing buccal films for oromucosal drug administration, adhesion is essential to ensure sufficient time for permeation of the active ingredient(s) through the oral mucosa and avoid the detachment and subsequent swallowing of the film. In this study, biomimetic materials were evaluated as a replacement for buccal mucosa in mucoadhesion testing and potential adhesives were compared regarding their suitability to increase the adhesion of hypromellose-based oromucosal films. Gelatin gels, as possible biomimetics, failed to mimic the buccal mucosa. Furthermore, esophageal tissue lead to a wider variance of adhesion data despite showing a good correlation with buccal tissue. A synthetic copolymer hydrogel based on hydroxyethylmethacrylate (HEMA) and N-acryloyl glucosamine (AGA) was able to mimic the buccal mucosa in these tests and reduced the variation in the data compared to animal tissue. Adding polyacrylic acid and polyvinylpyrrolidone to the film formulations at a concentration of 5% w/w approximately doubled the maximum detachment force and work of adhesion. Sodium alginate enhanced the adhesive properties moderately but adding chitosan did not significantly increase mucoadhesion. Polyvinylpyrrolidone and polyacrylic acid are rated as strong adhesion enhancers for buccal films and the HEMA/AGA hydrogel is considered as a suitable alternative for animal mucosa in mucoadhesion testing.

Preparation and evaluation of rapid disintegrating formulation from coated microneedle

Microneedles (MNs), one of the transdermal drug delivery systems, have received extensive interest as an alternative to parenteral or parenteral administrations. For the successful drug delivery of coated MNs, the coated drug or chemical of MNs should be dissolved by skin's interstitial fluid and completely released from the MNs. Thus, the rapid disintegration of the drug from MNs plays a crucial role in ideal drug delivery of MNs. In this study, we developed the rapid disintegration coating formulation to reduce the application time of MN. The rapid disintegration MN was developed using polymers (PVA or HPMC), glycerol, croscarmellose sodium, tween 80, and Brij, as thickener, plasticizer, disintegrating agent, and surfactants, respectively. HPMC MN showed the burst release and rapid disintegration. Moreover, the drug from HPMC MN was successfully delivered into porcine skin within 1 min. In toxicological evaluation, the HPMC MN did not alter the liver and kidney function. Besides, HPMC MN did not induce the acute inflammation and change of skin structure after the application on rat skin. Thus, the coating formulation in this study could be one of the options for the development of safe and rapid disintegration MN.

Improved Bioavailability of Ebastine through Development of Transfersomal Oral Films

The main objective of this research work was the development and evaluation of transfersomes integrated oral films for the bioavailability enhancement of Ebastine (EBT) to treat allergic rhinitis. The flexible transfersomes, consisting of drug (EBT), lipid (Phosphatidylcholine) and edge activator (EA) Polyoxyethylene sorbitan monooleate or Sorbitan monolaurate, were prepared with the conventional thin film hydration method. The developed transfersomes were further integrated into oral films using the solvent casting method. Transfersomes were evaluated for their size distribution, surface charge, entrapment efficiency (EE%) and relative deformability, whereas the formulated oral films were characterized for weight, thickness, pH, folding endurance, tensile strength, % of elongation, degree of crystallinity, water content, content uniformity, in vitro drug release and ex vivo permeation, as well as in vivo pharmacokinetic and pharmacodynamics profile. The mean hydrodynamic diameter of transfersomes was detected to be 75.87 ± 0.55 nm with an average PDI and zeta potential of 0.089 ± 0.01 and 33.5 ± 0.39 mV, respectively. The highest deformability of transfersomes of 18.52 mg/s was observed in the VS-3 formulation. The average entrapment efficiency of the transfersomes was about 95.15 ± 1.4%. Transfersomal oral films were found smooth with an average weight, thickness and tensile strength of 174.72 ± 2.3 mg, 0.313 ± 0.03 mm and 36.4 ± 1.1 MPa, respectively. The folding endurance, pH and elongation were found 132 ± 1, 6.8 ± 0.2 and 10.03 ± 0.4%, respectively. The ex vivo permeability of EBT from formulation ETF-5 was found to be approximately 2.86 folds higher than the pure drug and 1.81 folds higher than plain film (i.e., without loaded transfersomes). The relative oral bioavailability of ETF-5 was 2.95- and 1.7-fold higher than that of EBT-suspension and plain film, respectively. In addition, ETF-5 suppressed the wheal and flare completely within 24 h. Based on the physicochemical considerations, as well as in vitro and in vivo characterizations, it is concluded that the highly flexible transfersomal oral films (TOFs) effectively improved the bioavailability and antihistamine activity of EBT.

The Impact of the Preparation Method on the Properties of Orodispersible Films with Aripiprazole: Electrospinning vs. Casting and 3D Printing Methods

Orodispersible films (ODFs) address the needs of pediatric and geriatric patients and people with swallowing difficulties due to fast disintegration in the mouth. Typically, they are obtained using the solvent casting method, but other techniques such as 3D printing and electrospinning have already been investigated. The decision on the manufacturing method is of crucial importance because it affects film properties. This study aimed to compare electrospun ODFs containing aripiprazole and polyvinyl alcohol with films prepared using casting and 3D printing methods. Characterization of films included DSC and XRD analysis, microscopic analysis, the assessment of mechanical parameters, disintegration, and dissolution tests. Simplified stability studies were performed after one month of storage. All prepared films met acceptance criteria for mechanical properties. Electrospun ODFs disintegrated in 1.0 s, which was much less than in the case of other films. Stability studies have shown the sensitivity of electrospun films to the storage condition resulting in partial recrystallization of ARP. These changes negatively affected the dissolution rate, but mechanical properties and disintegration time remained at a desirable level. The results demonstrated that electrospun fibers are promising solutions that can be used in the future for the treatment of patients with swallowing problems.

Development and Evaluation of Fluoxetine Fast Dissolving Films: An Alternative for Noncompliance in Pediatric Patients

The most used pharmaceutical formulations for children are syrups, suppositories, soft chewable capsules, and mini-tablets. Administrating them might create an administration discomfort. This study aimed to develop and evaluate orodispersible films (ODFs) for pediatric patients in which the fluoxetine (FX) is formulated in the polymeric matrix. Six FX fast dissolving films (10 mg FX/ODF), FX1, FX2, FX3, FX4, FX5, and FX6, were prepared by solvent casting technique. In the composition of the ODFs, the concentration of the hydroxypropyl methylcellulose and the concentration of the propylene glycol were varied. Each formulation of fluoxetine ODF was evaluated by determining the tensile strength, folding endurance, disintegration, behavior in the controlled humidity and temperature conditions, and adhesiveness. All the obtained results were compared with the results obtained for six ODFs prepared without FX. The disintegration time of the FX ODFs was of maximum 88 s for FX2. Via the in vitro releasing study of the FX from the ODFs it was noticed that FX1 and FX2 allow a better release of the drug 99.98 ± 3.81% and 97.67 ± 3.85% being released within 15 min. From the obtained results it was also confirmed that FX ODFs were found to follow first-order release kinetic.

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.

Development, In Vitro and In Vivo Evaluation of Racecadotril Orodispersible Films for Pediatric Use

The present study endeavored to develop orodispersible films (ODFs) containing 30 mg racecadotril for pediatric use, which focuses on improving the compliance of pediatric patients and reducing risk of choking. The challenge of this study is to prepare high drug loading ODFs with successful mechanical and physicochemical properties. Compatibilities between drug and different polymers (hydroxypropyl methylcellulose, HPMC; polyvinyl alcohol, PVA; low-substituted hydroxypropyl cellulose, L-HPC; pullulan, PU) were investigated to select stable and safe film-forming polymers. Afterwards, the study explored the maximum amount of racecadotril incorporated into PVA films and PU films. Subsequently, disintegrant (Lycoat RS720, 4-10%, w/w) and plasticizers (glycerol, 2-6%, w/w) were investigated to reduce disintegration time of PVA films and enhance the flexibility of PU films, respectively. Formulation characteristics (appearance, tensile strength, percent elongation, disintegration time, drug content, weight, thickness, pH value, moisture content, moisture uptake, and Q_5min) of prepared ODFs were examined to obtain the optimal compositions of racecadotril ODFs. Differential scanning calorimetry (DSC) study, powder X-ray diffraction (XRD) study, Fourier transform infrared (FTIR) study, comparative in vitro dissolution study, and pharmacokinetic study in Beagle dogs of optimized racecadotril ODFs were then conducted. Eventually, ODFs containing 50% racecadotril, 38% PVA, 7% Lycoat RS720, 2% sucralose, 2% apricot, and 1% titanium dioxide could achieve desirable mechanical properties, disintegrating within a few seconds and releasing more than 85% drug within 5 min in four dissolution media. An in vivo study showed optimized racecadotril ODF and Hidrasec were bioequivalent in Beagle dogs. In summary, ODFs containing 30 mg racecadotril were successfully prepared by solvent casting method, and it was suitable for the administration to the pediatric patients.

Mucoadhesive polymeric films comprising polyvinyl alcohol, polyvinylpyrrolidone, and poloxamer 407 for pharmaceutical applications

Polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP) have been extensively studied for their use in film formation. Poloxamer 407 (P407) is a block copolymer that has thermo-responsive and surfactant properties when used in pharmaceutical systems. These polymers are already used in liquid or semi-solid systems for ocular and parenteral drug delivery. However, the effect of P407 presence in solid pharmaceutical films composed of different PVA:PVP ratios have not been investigated yet. Therefore, this work investigated the influence of P407 added to the binary polymer mixture of PVA and PVP for the development of solid films aiming for pharmaceutical applications. The rheological properties of dispersions were investigated, and films were prepared by solvent casting method using different P407:PVA:PVP ratios according to a factorial design 2³ (plus center point). The mechanical and in vitro mucoadhesive properties of films, as well as the disintegration time were investigated. Systems presented high mechanical resistance, mucoadhesion, and disintegration timeless than 180 s. It was found that higher concentrations of PVA increase mechanical properties and decrease disintegration time, and higher proportions of PVP and P407 increased mucoadhesion. The films could be classified as fast disintegrating films and represent a promising alternative for modifying drug delivery and pharmaceutical applications.

Development and in vitro evaluation of buccal mucoadhesive films for photodynamic inactivation of Candida albicans

Candidiasis is one of the most common diseases that occur in the oral cavity, caused mainly by the species Candida albicans. Methylene blue (MB) has a potential for microbial photoinactivation and can cause the destruction of fungi when applied in Photodynamic Therapy (PDT). Mucoadhesive films are increasingly being studied as a platform for drug application due to their advantages when compared to other pharmaceutical forms. The aim of this work was to develop mucoadhesive buccal film containing poloxamer 407 (P407), alcohol polyvinyl (PVA) and polyvinylpyrrolidone (PVP) for the release of MB aiming the photoinactivation of Candida albicans in buccal infections. Different amounts of P407 were added to the binary polymeric blends composed PVA and PVP. Formulations were characterized as morphology, thickness, density, bending strength, mechanical properties, water vapor transmission, disintegration time, mucoadhesion, DSC, ATR-FTIR, in vitro drug release profile and photodynamic inactivation. The films displayed physicochemical characteristics dependent of polymeric composition, mucoadhesive properties, fast MB release and were effective in photo inactivate the local growth of Candida albicans isolates. The formulation containing the lowest PVA and P407 amounts displayed the best performance. Therefore, data obtained from the film system show its potentially useful role as a platform for buccal MB delivery in photoinactivation of C. albicans, showing its potential for in vivo evaluation.

Technological development of mucoadhesive film containing poloxamer 407, polyvinyl alcohol and polyvinylpyrrolidone for buccal metronidazole delivery

Aim: This work aimed to develop a mucoadhesive film composed of a triblock copolymer (poloxamer 407), polyvinyl alcohol and polyvinylpyrrolidone for buccal modified delivery of metronidazole. Materials & methods: Three film formulations containing different polymer amounts were prepared by solvent casting. They were characterized as physicochemical, mechanical and mucoadhesive properties, and in vitro metronidazole release profiles. Results: Films displayed physicochemical, mechanical and mucoadhesive characteristics dependent of polymeric composition and drug presence. They could rapidly swell and promote the fast drug release (80% in 20 min) that was governed by Fickian diffusion. The films showed total disintegration in less than 90 s and total drug release in 30 min. Conclusion: Therefore, the formulations represent a promising alternative for modifying of buccal metronidazole delivery for pharmaceutical applications.

Characterization of Orodispersible Films: An Overview of Methods and Introduction to a New Disintegration Test Apparatus Using LDR - LED Sensors

Orodispersible Film (ODF) is a promising and progressive dosage form that offers exceptional drug delivery benefits to patients. Indeed, they are the most transformational alternatives to traditional/conventional dosage forms such as tablets and capsules. ODFs are portable and highly comfortable for self-administration by patients with swallowing problems. The key to gain end-user acceptance is to have an ODF with outstanding quality. Poor quality may lead to choking or spitting, accordingly leading to a lack of compliance. It is vital to employ suitable experimental methodologies that facilitate characterization or determination of the quality of ODF. Nonetheless, there are no standard techniques prescribed in official compendia of any country. But, there is a consensus in the thin-film research community about the characterization techniques that one relies on deciding the quality of an ODF. We review various experimental techniques and highlight its importance in determining the performance and quality of an ODF. We provide a relatively novel and inventive disintegration test apparatus, which works using 'Light Dependent Resistor (LDR) and Light Emitting Diode (LED) sensors' for clear and accurate determination of start and end disintegration time of an ODF.

Next Steps in 3D Printing of Fast Dissolving Oral Films for Commercial Production

3D printing technique has been utilised to develop novel and complex drug delivery systems that are almost impossible to produce by employing conventional formulation techniques. For example, this technique may be employed to produce tablets or Fast Dissolving oral Films (FDFs) with multilayers of active ingredients, which are personalised to patient's needs. In this article, we compared the production of FDFs by 3D printing to conventional methods such as solvent casting. Then, we evaluated the need for novel methods of producing fast dissolving oral films, and why 3D printing may be able to meet the shortfalls of FDF production. The challenges of producing 3D printed FDFs are identified at commercial scale by referring to the identification of suitable materials, hardware, qualitycontrol tests and Process Analytical Technology. In this paper, we discuss that the FDF market will grow to more than $1.3 billion per annum in the next few years and 3D printing of FDFs may share part of this market. Although companies are continuing to invest in technologies, which provide alternatives to standard drug delivery systems, the market for thin-film products is already well established. Market entry for a new technology such as 3D printing of FDFs will, therefore, be hard, unless, this technology proves to be a game changer. A few approaches are suggested in this paper.

Orodispersible films containing ball milled aripiprazole-poloxamer®407 solid dispersions

This research aimed at developing ODFs containing an antipsychotic drug - aripiprazole (ARP). ARP, as a BCS II class molecule, requires enhancing its water solubility prior to formulating. Therefore, a solid dispersion of ARP - Poloxamer® 407 was prepared by ball milling, then incorporated into the films. It was found that co-processing led to an over 100-fold increase in drug solubility in comparison with pure drug. Moreover, ODFs with solid dispersion showed faster drug release (>95% below 15 min) and disintegration (<30 s), compared with raw ARP films. These results are believed to be due to the solubilization effect of poloxamer and enhanced wettability of the film. Films containing solid dispersions were found to possess smoother film surfaces and favorable mechanical properties - flexibility and strength. The ODF formulations, prepared by a casting method, were based on three different polymers (Kollicoat® IR, Kollicoat® Protect or PVA). It was found that not only the form of the incorporated drug, but also the type of film-forming polymer had an impact on the analyzed parameters. The use of PVA was beneficial in the film formulation with aripiprazole in comparison to other tested film-forming polymers.

How to assess orodispersible film quality? A review of applied methods and their modifications

In recent years, there has been a tendency toward creating innovative, easy to use and patient-friendly drug delivery systems suitable for every consumer profile, which would ensure safety, stability and acceptability of a drug. One of the relatively novel and promising approaches is the manufacture of orodispersible films (ODFs), which is an upcoming area of interest in drug delivery. They are defined as polymer thin films that disintegrate in the oral cavity within seconds, without drinking water or chewing, and eliminate the risk of choking. Gaining special usefulness in therapies of children and the elderly, ODFs seem to fill the gap in the range of preparations available for these groups of patients. As no detailed monography of ODFs including testing methods and uniform requirements has been presented in any of the pharmacopoeias to date, the aim of this article is to give an overview of the applied testing methods, their modifications and innovative approaches related to ODF quality assessment.