Effect of storage on the physical stability of thin polymethacrylate-perphenazine films

Co-delivery of terbinafine hydrochloride and urea with an in situ film-forming system for nail targeting treatment

Onychomycosis is a chronic nail disorder consisting of a fungal infection that causes physical and psychosocial discomfort to patients. However, its treatment remains challenging owing to the barrier of the highly keratinized nail plate and the short time that conventional formulations reside on nails. In this work, we developed an in situ film-forming system(IFFS) based on Eudragit® RLPO to co-deliver terbinafine hydrochloride (TBH) and urea, i.e., TBH-urea-RLPO IFFS, with the aim of overcoming the nail barrier, prolonging the residence time, and efficiently treating onychomycosis. The IFFS formulation formed a thin film with good appearance and adhesion upon application in situ. The physical states of TBH and urea in the film were evaluated with polarization microscopy and powder X-ray diffraction. TBH and urea were both amorphousmiscible components within the RLPO film. TBH release from TBH-urea-RLPO IFFS fitted to the Korsmeyer-Pappas model, and the cumulative release at 72 h was significantly higher than that from commercial preparations (Lamisil Pedisan® once). In vitro permeation of TBH from TBH-urea-RLPO IFFS through bovine hoof membranes was evaluated in comparison with the film containing TBH alone (TBH-RLPO) and commercial preparations. The retention and cumulative permeated amount of TBH were significantly enhanced for the TBH-urea-RLPO IFFS (170.80 ± 44.63 μg/cm²vs 75.49 ± 21.50 μg/cm²vs 60.25 ± 27.38 μg/cm²; 61.81 ± 16.09 μg/cm²vs 21.80 ± 11.56 μg/cm²vs 7.91 ± 1.03 μg/cm², respectively), and the membranes treated with different formulations were observed with SEM and FTIR to identify the denaturing effect of urea on bovine hoof keratin. In vitro antifungal tests against Trichophyton rubrum,Microsporum canis, Fusarium, and Aspergillus fumigatus were cultured on Muller-Hinton agar; the findings indicated that TBH-urea-RLPO IFFS enhanced TBH antifungal activity. Overall, the results support that TBH-urea-RLPO IFFS is an efficient and promising approach for onychomycosis targeting treatment.

Jet dispensing of multi-layered films for the co-delivery of three antihypertensive agents

Three-layer thin films comprising of two polymers as substrate (ethyl cellulose and, copovidone K28) and three antihypertensive agents (hydrochlorothiazide, amiloride HCl, and carvedilol) were printed using jet dispensing technology. Two film formulations with different ethyl cellulose to copovidone K28 ratio (i.e., 90/10 and 50/50 w/w) were prepared using a three-course dispensing. The films were characterized regarding surface morphology, solid-state properties, polymer-drug interactions, drug distribution in each layer, and in vitro drug release. All the components of the films were found to be in the amorphous state apart from hydrochlorothiazide which retained its crystallinity. FT-IR spectroscopy revealed hydrogen bond interactions between carvedilol and copovidone K28. Combinations of ethyl cellulose and copovidone K28 provide suitable polymeric film substrates with the ability to modify drug release. Particularly, decreased ethyl cellulose to copovidone K28 weight ratio was found to suppress the crystallization of hydrochlorothiazide and to increase the release rate of the dispensed drugs. Jet dispensing was found to be a rapid technology for the preparation of multi-layered films that can be used as personalized formulations for the delivery of combinations of drugs.