Effects of Various Drying Times on the Properties of 3D Printed Orodispersible Films

From conception to consumption: Applications of semi-solid extrusion 3D printing in oral drug delivery

Semi-Solid Extrusion 3D printing (SSE 3DP) has emerged as a promising technology for fabricating oral drug formulations, offering significant opportunities for personalized medicine and tailored therapeutic outcomes. SSE 3DP is particularly advantageous for producing soft and chewable drug products and is well-suited for formulations containing thermosensitive drugs due to its low-temperature printing process. Among various 3D printing techniques, SSE 3DP holds considerable potential for point-of-care applications, enabling the on-demand production of patient-specific dosage forms. Despite these advantages, SSE 3DP faces certain limitations that affect its overall development and widespread adoption. This review provides a comprehensive overview of SSE 3DP's fundamental principles, current applications, and future prospects in oral drug delivery. It also addresses the challenges and limitations associated with SSE 3DP and examines the current outlook of this technique in oral drug delivery applications. An example of such a challenge is the lack of a harmonized method for evaluating rheological properties. To address this issue, the review describes a methodology for obtaining information related to extrudability and shape fidelity from rheological properties. Overall, this review aims to highlight the transformative potential of SSE 3DP in the pharmaceutical landscape, paving the way for tailored, and patient-centric therapies.

Effect of processing conditions on the physical-chemical and mechanical properties of chitosan-alginate polyelectrolyte complex films for potential wound dressing application

The combination of chitosan and alginate leads to the formation of polyelectrolyte complexes (PECs) that have been mainly used for applications such as wound dressings in biomedical areas. However, processing conditions can affect the resulting complex structure, influencing the final material properties. This work aims to evaluate the influence of processing conditions on the physical-chemical and mechanical properties of chitosan-alginate PEC films for wound dressing applications. The study was carried out using a Box-Behnken design, with controlled variables including pH, agitation speed, amounts of crosslinker and plasticizer, and the type of acid used in chitosan solubilization. Response variables were thickness, liquid absorption capacity, water vapor barrier, and mechanical properties, which are important characteristics in defining the applicability of dressings. All studied factors, as well as their interactions, showed significant effects on the properties of interest. The mathematical models obtained for the studied properties did not have a predictive character but rather a qualitative one, providing a good insight into the behavior of these materials regarding the modification of the evaluated experimental conditions, which strongly influence the characteristics of chitosan-alginate PEC films. Additional swelling and FTIR analyses performed for a selected sub-set of samples confirmed, respectively: (i) the high equilibrium values and stability at the equilibrium of the films regarding liquid absorption for both water and PBS; (ii) no degradation of the chitosan and alginate functional groups or loss of interaction between them under the considered processing conditions.

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.

Atorvastatin liposomes in a 3D-printed polymer film: a repurposing approach for local treatment of oral candidiasis

Oral candidiasis (OC) is an opportunistic fungal infection, common amongst the elderly and the immunocompromised. Unfortunately, the therapeutic efficacy of common antifungals is imperiled by the rise of antifungal drug resistance. An alternative promising therapeutic option possibly contributing to antifungal therapy is drug repurposing. Herein, we aimed to employ novel pharmaceutical drug delivery for enhancing the emerging antifungal potential of the hypocholesterolemic drug atorvastatin (ATV). ATV-propylene-glycol-liposomes (ATV/PG-Lip) were prepared then integrated in 3D-printed (3DP) mucoadhesive films comprising chitosan, polyvinyl-alcohol and hydroxypropyl methylcellulose, as an innovative blend, for the management of OC. ATV/PG-Lip demonstrated good colloidal properties of particle size (223.3 ± 2.1 nm), PDI (0.12 ± 0.001) and zeta potential (-18.2 ± 0.3 mV) with high entrapment efficiency (81.15 ± 1.88%) and sustained drug release. Also, ATV/PG-Lip showed acceptable three-month colloidal stability and in vitro cytocompatibility on human gingival fibroblasts. The developed 3DP-films exhibited controlled ATV release (79.4 ± 1.4% over 24 h), reasonable swelling and mucoadhesion (2388.4 ± 18.4 dyne/cm2). In vitro antifungal activity of ATV/PG-Lip was confirmed against fluconazole-resistant Candida albicans via minimum inhibitory concentration determination, time-dependent antifungal activity, agar diffusion and scanning electron microscopy. Further, ATV/PG-Lip@3DP-film exceeded ATV@3DP-film in amelioration of infection and associated inflammation in an in vivo oral candidiasis rabbit model. Accordingly, the results confirm the superiority of the fabricated ATV/PG-Lip@3DP-film for the management of oral candidiasis and tackling antifungal resistance.

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.

Development of 3D Printed Multi-Layered Orodispersible Films with Porous Structure Applicable as a Substrate for Inkjet Printing

The direct tailoring of the size, composition, or number of layers belongs to the advantages of 3D printing employment in producing orodispersible films (ODFs) compared to the frequently utilized solvent casting method. This study aimed to produce porous ODFs as a substrate for medicated ink deposited by a 2D printer. The innovative semi-solid extrusion 3D printing method was employed to produce multilayered ODFs, where the bottom layer assures the mechanical properties. In contrast, the top layer provides a porous structure for ink entrapment. Hydroxypropyl methylcellulose and polyvinyl alcohol were utilized as film-forming polymers, glycerol as a plasticizer, and sodium starch glycolate as a disintegrant in the bottom matrix. Several porogen agents (Aeroperl^® 300, Fujisil^®, Syloid^® 244 FP, Syloid^® XDP 3050, Neusilin^® S2, Neusilin^® US2, and Neusilin^® UFL2) acted as porosity enhancers in the two types of top layer. ODFs with satisfactory disintegration time were prepared. The correlation between the porogen content and the mechanical properties was proved. A porous ODF structure was detected in most samples and linked to the porogen content. SSE 3D printing represents a promising preparation method for the production of porous ODFs as substrates for subsequent drug deposition by 2D printing, avoiding the difficulties arising in casting or printing medicated ODFs directly.

Orodispersible Films-Current State of the Art, Limitations, Advances and Future Perspectives

Orodispersible Films (ODFs) are drug delivery systems manufactured with a wide range of methods on a big scale or for customized medicines and small-scale pharmacy. Both ODFs and their fabrication methods have certain limitations. Many pharmaceutical companies and academic research centers across the world cooperate in order to cope with these issues and also to find new formulations for a wide array of APIs what could make their work profitable for them and beneficial for patients as well. The number of pending patent applications and granted patents with their innovative approaches makes the progress in the manufacturing of ODFs unquestionable. The number of commercially available ODFs is still growing. However, some of them were discontinued and are no longer available on the markets. This review aims to summarize currently marketed ODFs and those withdrawn from sale and also provides an insight into recently published studies concerning orodispersible films, emphasizing of utilized APIs. The work also highlights the attempts of scientific communities to overcome ODF's manufacturing methods limitations.

The Use of Micro-Ribbons and Micro-Fibres in the Formulation of 3D Printed Fast Dissolving Oral Films

Three-dimensional printing (3DP) allows production of novel fast dissolving oral films (FDFs). However, mechanical properties of the films may not be desirable when certain excipients are used. This work investigated whether adding chitosan micro-ribbons or cellulose microfibres will achieve desired FDFs by fused deposition modelling 3DP. Filaments containing polyvinyl alcohol (PVA) and paracetamol as model drug were manufactured at 170 °C. At 130 °C, filaments containing polyvinylpyrrolidone (PVP) and paracetamol were also created. FDFs were printed with plain or mesh patterns at temperatures of 200 °C (PVA) or 180 °C (PVP). Both chitosan micro-ribbons and cellulose micro-fibres improved filament mechanical properties at 1% w/w concentration in terms of flexibility and stiffness. The filaments were not suitable for printing at higher concentrations of chitosan micro-ribbons and cellulose micro-fibres. Furthermore, mesh FDFs containing only 1% chitosan micro-ribbons disintegrated in distilled water within 40.33 ± 4.64 s, while mesh FDFs containing only 7% croscarmellose disintegrated in 55.33 ± 2.86 s, and croscarmellose containing films showed signs of excipient scorching for PVA polymer. Cellulose micro-fibres delayed disintegration of PVA mesh films to 108.66 ± 3.68 s at 1% w/w. In conclusion, only chitosan micro-ribbons created a network of hydrophilic channels within the films, which allowed faster disintegration time at considerably lower concentrations.

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.