The process of drying thin polymer films is an important operation that influences the film structure and solid state, and the stability of the product. The purpose of this work was to study and model the drying kinetics of multicomponent films based on two polymers: hydroxypropyl methylcellulose (HPMC, amorphous) and polyvinyl alcohol (PVA, semicrystalline). The isothermal drying kinetics of the films at different temperatures (40, 60, and 80°C) were studied using thermo-gravimetric analysis (TGA) and convection oven methods. Solid-state characterization tools used in the study included polarization and hot-stage microscopy, scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). The drying kinetics of HPMC and PVA films in the TGA apparatus and convection oven were comparable. The three-parameter (W_max, τ, n) Hill equation successfully modeled the experimental drying kinetics. The time factor τ in the Hill equation nicely explained two drying phases in the films. Solid-state phase changes occurring in the films during dehydration had a bearing on the drying kinetics and mechanisms. TGA can be used as a simple tool to determine the end points in drying processes using ovens or tunnels. The three-parameter Hill equation explained the drying kinetics and diffusion mechanisms of the solvent through the polymer films for the first time. This study advances our understanding of film drying, in particular for pharmaceutically relevant thin films.

Warfarin is a widely used anticoagulant that is critical in reducing patient morbidity and mortality associated with thromboembolic disorders. However, its narrow therapeutic index and large inter-individual variability can lead to complex dosage regimes. Formulating warfarin as an orodispersible film (ODF) using thermal ink-jet (TIJ) printing could enable personalisation of therapy to simplify administration. Commercial TIJ printers are currently unsuitable for printing the milligram dosages, typically required for warfarin therapy. As such, this study aimed to modify a commercial TIJ printing system to formulate personalised warfarin ODFs containing therapeutic dosages. A TIJ printer was modified successfully with the printer functionality intact; the substrate (paper) rolling mechanism of the printer was replaced by printing onto a stationary stage. Free film substrates were composed of hydroxypropyl methylcellulose (20%w/w) and glycerol (3%w/w). The resulting ODFs were characterised for morphology, disintegration, solid-state properties and drug content. Printed film stability was assessed at 40 °C/75% relative humidity for 30 days. Therapeutic warfarin doses (1.25 and 2.5 mg) were successfully printed onto the film substrates. Excellent linearity was observed between the theoretical and measured dose by changing the warfarin feed concentration (R² = 0.9999) and length of the print objective, i.e. the Y-value, (R² = 0.9998). Rapid disintegration of the ODFs was achieved. As such, this study successfully formulated personalised warfarin ODFs using a modified TIJ printer, widening the range of applications for TIJ printing to formulate narrow therapeutic index drugs.

Hypothyroidism is a chronic and debilitating disease that is estimated to affect 3% of the general population. Clinical experience has highlighted the synergistic value of combining triiodothyronine (T₃) and thyroxine (T₄) for persistent or recurrent symptoms. However, thus far a platform that enables the simultaneous and independent dosing of more than one drug for oral administration has not been developed. Thermal inkjet (TIJ) printing is a potential solution to enable the dual deposition of T₃ and T₄ onto orodispersible films (ODFs) for therapy personalisation. In this study, a two-cartridge TIJ printer was modified such that it could print separate solutions of T₃ and T₄. Dose adjustments were achieved by printing solutions adjacent to each other, enabling therapeutic T₃ (15–50 μg) and T₄ dosages (60–180 μg) to be successfully printed. Excellent linearity was observed between the theoretical and measured dose for both T₃ and T₄ (R² = 0.982 and 0.985, respectively) by changing the length of the print objective (Y-value). Rapid disintegration of the ODFs was achieved (< 45 seconds). As such, this study for the first time demonstrates the ability to produce personalised dose combinations by TIJ printing T₃ and T₄ onto the same substrate for oral administration.

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

The effect of different plasticizers (glycerol, vitamin E TPGS and triacetin) and their concentrations on the physico-mechanical properties of pullulan based oral films was studied. A full factorial (3²) design of experiments was used. Elastic modulus, tensile strength, elongation at break and disintegration time were selected as response variables. Modulated differential scanning calorimeter (MDSC) was used for determining glass transition temperature (T_g) of pullulan films. The surface morphology of films was evaluated by SEM, while ATR-FTIR was used to obtain a molecular level understanding of polymer-plasticizer interactions. The DoE analysis allowed for the modelling of tensile strength and elongation at break. The highest elongations were observed in glycerol at 20% w/w. Majority of the films disintegrated within one minute without significant differences. ATR-FTIR spectra of pullulan alone and different plasticizer blend films show characteristic molecular interactions. The present study concluded that glycerol is suitable plasticizer compared to others for manufacturing pullulan based oral films.

The aim of the present work was to prepare tadalafil (TDF) nanocrystals-loaded oral polymeric films (OFs) and investigate the effect of hydrophilic surfactants and drug loads on the physico-mechanical and dissolution properties. The nanosuspensions of TDF were prepared by high shear homogenization. HPMC based placebo casting film gel was prepared and mixed with TDF nanosuspensions. Films were casted using an automated film applicator and dried at 60 °C for 45 min. Particle size (PS), polydispersity index (PDI), and zeta potential (ZP) of TDF nanosuspensions were measured in a Zetasizer. The films were characterized using SEM, AFM, DSC, TGA and PXRD. The mechanical properties and in vitro drug release were determined using standard methods. TDF existed in crystalline form and the particles remained in the nano-range in redispersed films. TDF nanocrystals were embedded in the polymeric matrix and the drug loaded films were rough on the surface. Mechanical properties of the films varied with changes in drug load and surfactant. Significant changes in the disintegration times were noticed in films containing surfactants compared to surfactant-free films. About 80% of the drug release was observed between 3 and 30 min. TPGS showed better TDF release from the films at different drug loads

Boswellic acid (BA) is an ancient herbal drug prescribed in the Indian traditional medicine systems (Ayurveda) for treatment of coughs, colds, hoarseness, bronchitis, asthma, dyspnea and diarrhea. Current research suggests it also has therapeutic potential in modern medical practice. Therefore, it is of interest to the research community to consolidate the preclinical and clinical findings on BA. The aim of this review was to comprehensively cover the plant sources, phytochemistry and physicochemical properties of BA along with its medicinal properties, safety, toxicity, and regulatory status. The review also discussed the challenges associated with drug delivery and some feasible approaches for addressing these. Four electronic databases (Scifinder, Unbound Medline, PubMed and Science Direct) and two internet search engines (Scirus and Google Scholar) were extensively searched without any time constraint.The many studies discussed in the review indicated therapeutic potential for BA in the treatment of a range of chronic diseases including arthritis, cancer, asthma and diabetes. It is hoped that this review will help researchers identify relevant research questions leading to the development of effective formulations and a better understanding of the safety of BA, with the aim of promoting it as a mainstream treatment for various diseases in clinical practice. 

Nanofiber mats or films are promising platforms that can offer unique opportunities in oromucosoal drug delivery. However, the conventional film forming technologies are unable to produce mats with unique internal microstructure and properties. Thus, the present study was aimed to develop electrospun nanofiber mats of a model drug -ondansetron hydrochloride (OND) for ultrafast drug release. Polyvinyl alcohol (PVA), a water soluble synthetic polymer was used in the preparation of nanofiber mats and casting film. The OND nanofiber mats and conventional films were prepared by electrospinning and casting methods, respectively. Different electrospinning process variables (feed rate, electric voltage and tip to collector distance) were investigated. Nanofiber mats and casted films were characterized using Scanning electron microscopy (SEM), Atomic force microscopy (AFM), Differential scanning calorimetry (DSC), Powder X-ray diffraction (PXRD), and Attenuated total reflection – Fourier transform infrared spectroscopy (ATR-FTIR). The folding endurance, drug content, wetting behaviour and disintegration properties and in-vitro drug release studies were also performed.The SEM and AFM had revealed that the nanofiber mats were formed with smooth uniform texture. Solid state studies indicated that the OND was in amorphous state and uniformly dispersed in PVA mats and a film. The electrospun nanofiber mat and casted film of OND showed sufficient mechanical properties. Wet sponge method suggested that OND nanofiber mats were simultaneously wetted and disintegrated within 10 s, which is ultrafast compared to casted films. The total amount of OND was released in 90 s (1.5 min) and 1800 s (30 min) from OND-PVA electrospun nanofiber mats and casted film, respectively. OND nanofiber mats can be promising alternatives to existing solid dosage forms for ultrafast release of drugs.

The aim of the present research work was to develop asenapine (ASM) loaded nanostructured lipid carriers (ANLC) for the delivery of drugs in the brain by an intranasal route to enhance therapeutic efficacy. A quality by design approach was used for development and optimization of ANLC. A total of five independent variables were selected, in which three were compositions and two were process variables, while particle size and entrapment efficiency were selected as response variables. The final optimized batch was evaluated by various in vitro characterizations as well as in vivo brain and plasma pharmacokinetic studies. Finally, the ANLC was assessed for efficacy and safety profiling for upto three weeks by a behavior model viz. catalepsy, induced locomotor and paw test in Charles Foster rats. The observed particle size, entrapment efficiency and zeta potential of ANLC was found to be 167.30 +/- 7.52 nm, 83.50 +/- 2.48% and -4.33 +/- 1.27 mV, respectively. Surface characterization studies demonstrated a spherical shape with a smooth surface of ANLC which follows the Korsmeyer-Peppas in vitro release kinetic model (r(2) = 0.9911, n = 0.53). A brain pharmacokinetic study indicated a significantly higher (p < 0.05) peak drug concentration (C-max: 74.13 +/- 6.73 ng mL(-1)), area under the drug concentration-time curve (AUC(0-24) (h): 560.93 +/- 27.85 h ng mL(-1)) and mean residence time (MRT: 7.1 +/- 0.13 h) of ANLC compared to ASM in the brain via an intranasal route. The results of behaviour studies of ANLC showed a significant decrease in extra-pyramidal side effects with increasing antipsychotic effect after 1-2 week(s) of treatment. These findings demonstrate that nanostructured lipid carriers could be a new promising drug delivery system for intranasal delivery of asenapine in the treatment of schizophrenia