The Influence of Tea Tree Oil on Antifungal Activity and Pharmaceutical Characteristics of Pluronic® F-127 Gel Formulations with Ketoconazole.

Fungal skin infections are currently a major clinical problem due to their increased occurrence and drug resistance. The treatment of fungal skin infections is based on monotherapy or polytherapy using the synergy of the therapeutic substances. Tea tree oil (TTO) may be a valuable addition to the traditional antifungal drugs due to its antifungal and anti-inflammatory activity. Ketoconazole (KTZ) is an imidazole antifungal agent commonly used as a treatment for dermatological fungal infections. The use of hydrogels and organogel-based formulations has been increasing for the past few years, due to the easy method of preparation and long-term stability of the product. Therefore, the purpose of this study was to design and characterize different types of Pluronic® F-127 gel formulations containing KTZ and TTO as local delivery systems that can be applied in cases of skin fungal infections. The influence of TTO addition on the textural, rheological, and bioadhesive properties of the designed formulations was examined. Moreover, the in vitro release of KTZ, its permeation through artificial skin, and antifungal activity by the agar diffusion method were performed. It was found that obtained gel formulations were non-Newtonian systems, showing a shear-thinning behaviour and thixotropic properties with adequate textural features such as hardness, compressibility, and adhesiveness. Furthermore, the designed preparations with TTO were characterized by beneficial bioadhesive properties. The presence of TTO improved the penetration and retention of KTZ through the artificial skin membrane and this effect was particularly visible in hydrogel formulation. The developed gels containing TTO can be considered as favourable formulations in terms of drug release and antifungal activity.

A Universal and Reversible Wet Adhesive via Straightforward Aqueous Self-Assembly of Polyethylenimine and Polyoxometalate.

The excellent adhesion of mussels under wet conditions has inspired the development of numerous catechol-based wet adhesives. Nevertheless, the performance of catechol-based wet adhesive suffers from the sensitivity toward temperature, pH, or oxidation stimuli. Therefore, it is of great significance to develop non-catechol-based wet adhesives to fully recapitulate nature's dynamic function. Herein, a novel type of non-catechol-based wet adhesive is reported, which is readily formed by self-assembly of commercially available branched polyethylenimine and phosphotungstic acid in aqueous solution through the combination of electrostatic interaction and hydrogen bonding. This wet adhesive shows reversible, tunable, and strong adhesion on diverse substrates and further exhibits high efficacy in promoting biological wound healing. During the healing of the wound, the as-prepared wet adhesive also possesses inherent antimicrobial properties, thus avoiding inflammations and infections due to microorganism accumulation.

Gellan Gum-Based Bilayer Mucoadhesive Films Loaded with Moxifloxacin Hydrochloride and Clove Oil for Possible Treatment of Periodontitis.

BACKGROUND/OBJECTIVE: Periodontitis is a widely spread oral infection and various antibiotics are utilized for its treatment, but high oral doses and development of antibiotic resistance limit their use. This study was aimed at development of natural polymer-based mucoadhesive bilayer films loaded with moxifloxacin hydrochloride (Mox) and clove essential oil (CEO) to potentially combat bacterial infection associated with periodontitis. METHODS: Films were synthesized by double solvent casting technique having an antibiotic in the gellan gum-based primary layer with clove oil in a hydroxyethyl cellulose-based secondary layer. RESULTS: Prepared films were transparent, flexible, and showed high antibacterial response against both gram-positive and gram-negative bacteria. The films showed excellent pharmaceutical attributes in terms of drug content, folding endurance, swelling index, and mucoadhesive strength. Solid state characterization of formulation showed successful incorporation of drug and oil in separate layers of hydrogel structure. An in-vitro release study showed an initial burst release of drug followed by sustained release for up to 48 hours. CONCLUSION: The prepared mucoadhesive bilayer buccal films could be used as a potential therapeutic option for the management of periodontitis.

Self-stick membrane based on grafted gum Arabic as active food packaging for cheese using cinnamon extract.

Encapsulation of volatile essential oils has been investigated to provide an active food packaging (AFP) material with more control over their fast release and pungent smell. In this work, Gum Arabic-based adhesive membrane was developed as a self-stick AFP material, delivering cinnamon essential oil (CEO) in vapor phase. Gum Arabic (GA) was grafted with butyl acrylate (BA) and hydroxyethyl methacrylate [GA-g-poly(BA-HEMA)]. Adhesive membrane was characterized by means of spectral, physicochemical and rheological analysis. GA-adhesive membrane made of 5% wt/v GA, 3.5 m mol HEMA, and 87 m mol BA with 21 N/m tack are loaded with 4, 8 and 10% v/v of CEO and used for antimicrobial bioassays. GA-g-poly(BA-HEMA) membrane prolonged CEO release up to 2 days. 8%v/v CEO showed superior activities against both Gram negative and positive bacteria. Shelf-life of cheese samples, packed with the self-stick membranes loaded with cinnamon extract, has extended from 3 to 8 weeks. Cheese samples that inoculated with shiga toxin producing E. coli O157:H7 and packed in plastic boxes with the self-stick AFP (4, 8 and 10 % CEO), showed significant reduction in the total bacteria counts.

Potential Anti-Alzheimer Agents from Guanidinyl Tryptophan Derivatives with Activities of Membrane Adhesion and Conformational Transition Inhibitions.

Guanidinyl tryptophan derivatives TGN1, TGN2, TGN3, and TGN4 were synthesized, and these compounds were shown to possess in vitro inhibitory activity for amyloid aggregation in a previous study. Nevertheless, the influence of the TGN series of compounds on the binding and permeation behaviors of an Aß monomer to the cell membranes was not elucidated. In this study, we investigated the effect of compounds in the TGN series on the behavior of an Aß monomer regarding its toxicity toward the bilayer lipid membrane using molecular dynamics (MD) simulation. MD simulations suggest that TGN4 is a potential agent that can interfere with the movement of the Aß monomer into the membrane. The MM-GBSA result demonstrated that TGN4 exhibits the highest affinity to the Aß1-42 monomer but has the lowest affinity to the bilayer. Moreover, TGN4 also contributes to a decrease in the binding affinity between the Aß1-42 monomer and the POPC membrane. Regarding the results of the binding mode and conformational analyses, a high number of amino-acid residues were shown to provide the binding interactions between TGN4 and the Aß1-42 monomer. TGN4 also reduces the conformational transition of the Aß1-42 monomer by means of interacting with the monomer. The present study presents molecular-level insights into how the TGN series of compounds affect the membrane adsorption and the conformational transition of the Aß1-42 monomer, which could be valuable for the further development of new anti-Alzheimer agents.

Optimally designed theranostic system based folic acids and chitosan as a promising mucoadhesive delivery system for encapsulating curcumin LbL nano-template against invasiveness of breast cancer.

Curcumin is a potential candidate in cancer therapy due to its ability to inhibit many signalling pathways at the same time of exposure because of its unique content of aromatic ring, B diketone, olefinic linker, and O methoxy phenolic groups. Its applications in biomedical therapy is limited because of its sensitivity, and its rapid degradation. In the current study, curcumin inserted into polyelectrolyte pairs (protamine and dextran) and then was functionalized by folic acid conjugated chitosan used for the first time, as theranostic system. Such this strategy allows to improve its mucoadhesion and penetration that increases their accumulation inside cancer cells. CUR-LbL NPs were then used to investigate drug release inside Human Mammary Carcinoma (MCF-7 cell lines) after their incubations for 3 h, 6 h and 24 h. Flow cytometry indicated that the percentages of apoptosis, necrosis and cell cycle arrest were increased significantly in MCF-7 cell lines treated by CUR-LbL NPs. Furthermore, SEM image showed many debris in the section of MCF-7 treated by CUR-LbL NPs. Here, it can be summarized that curcumin functionalized by multi-layered polyelectrolyte capsules can be used as a model to study the fate of the adsorbed nanocarriers and to investigate the drug release inside cells.

Experimental design, formulation and in vivo evaluation of a novel topical in situ gel system to treat ocular infections.

In situ gels have been extensively explored as ocular drug delivery system to enhance bioavailability and efficacy. The objective of present study was to design, formulate and evaluate ion-activated in situ gel to enhance the ocular penetration and therapeutic performance of moxifloxacin in ophthalmic delivery. A simplex lattice design was utilized to examine the effect of various factors on experimental outcomes of the in situ gel system. The influence of polymers (independent variables) such as gellan gum (X1), sodium alginate (X2), and HPMC (X3) on gel strength, adhesive force, viscosity and drug release after 10 h (Q10) were assessed. Selected formulation (MH7) was studied for ex vivo permeation, in vivo irritation and pharmacokinetics in rabbits. Data revealed that increase in concentration of polymers led to higher gel strength, adhesive force and viscosity, however, decreases the drug release. MH7 exhibited all physicochemical properties within acceptable limits and was stable for 6 months. Release profile of moxifloxacin from MH7 was comparable to the check point batches and followed Korsmeyer-Peppas matrix diffusion-controlled mechanism. Ocular irritation study signifies that selected formulation is safe and non-irritant for ophthalmic administration. In vivo pharmacokinetics data indicates significant improvement of moxifloxacin bioavailability (p < 0.0001) from MH7, as evidenced by higher Cmax (727 ± 56 ng/ml) and greater AUC (2881 ± 108 ng h/ml), when compared with commercial eye drops (Cmax; 503 ± 85 ng/ml and AUC; 978 ± 86 ng h/ml). In conclusion, developed in situ gel system (MH7) could offers a more effective and extended ophthalmic therapy of moxifloxacin in ocular infections when compared to conventional eye drops.

ERF4 and MYB52 transcription factors play antagonistic roles in regulating homogalacturonan de-methylesterification in Arabidopsis seed coat mucilage.

Homogalacturonan (HG), a component of pectin, is synthesized in the Golgi apparatus in its fully methylesterified form. It is then secreted into the apoplast where it is typically de-methylesterified by pectin methylesterases (PME). Secretion and de-esterification are critical for normal pectin function, yet the underlying transcriptional regulation mechanisms remain largely unknown. Here, we uncovered a mechanism that fine-tunes the degree of HG de-methylesterification (DM) in the mucilage that surrounds Arabidopsis thaliana seeds. We demonstrate that the APETALA2/ETHYLENE RESPONSE FACTOR (AP2/ERF) transcription factor (TF) ERF4 is a transcriptional repressor that positively regulates HG DM. ERF4 expression is confined to epidermal cells in the early stages of seed coat development. The adhesiveness of the erf4 mutant mucilage was decreased as a result of an increased DM caused by a decrease in PME activity. Molecular and genetic analyses revealed that ERF4 positively regulates HG DM by suppressing the expression of three PME INHIBITOR genes (PMEIs) and SUBTILISIN-LIKE SERINE PROTEASE 1.7 (SBT1.7). ERF4 shares common targets with the TF MYB52, which also regulates pectin DM. Nevertheless, the erf4-2 myb52 double mutant seeds have a wild-type mucilage phenotype. We provide evidence that ERF4 and MYB52 regulate downstream gene expression in an opposite manner by antagonizing each other's DNA-binding ability through a physical interaction. Together, our findings reveal that pectin DM in the seed coat is fine-tuned by an ERF4-MYB52 transcriptional complex.

Particle transfer and adherence to human skin compared with cotton glove and pre-moistened polyvinyl alcohol exposure sampling substrates.

Measurement of skin exposure to particles using interception (e.g., cotton gloves) and removal (e.g., wiping) sampling techniques could be inaccurate because these substrates do not have the same topography and adhesion characteristics as skin. The objective of this study was to compare particle transfer and adherence to cotton gloves, cotton gloves with artificial sebum, and a pre-moistened polyvinyl alcohol (PVA) material with bare human skin (fingertip, palm). Experiments were performed with aluminum oxide powder under standardized conditions for three types of surfaces touched, applied loads, contact times, and powder mass levels. In the final mixed model, the fixed effects of substrate, surface type, applied load, and powder mass and their significant two-way interaction terms explained 71% (transfer) and 74% (adherence) of the observed total variance in measurements. For particle mass transfer, compared with bare skin, bias was -77% (cotton glove with sebum) to +197% (PVA material) and for adherence bias ranged from -40% (cotton glove) to +428% (PVA material), which indicated under- and over-sampling by these substrates, respectively. Dermal exposure assessment would benefit from sampling substrates that better reflect human skin characteristics and more accurately estimate exposures. Mischaracterization of dermal exposure has important implications for exposure and risk assessment.

Brain targeting of agomelatine egg lecithin based chitosan coated nanoemulsion.

Intranasal drug delivery system has been proposed as an alternative delivery system to target agomelatine (AGO) to the brain and improving its bioavailability. Mucoadhesive egg lecithin nanoemulsions were optimized using D-optimal design and by investigating the effect of four independent variables: oil concentration (A), chitosan concentration (B), type of oil (C) and egg lecithin: oil (D). The responses of globule size, polydispersity index, zeta potential and drug content were evaluated. The optimized agomelatine mucoadhesive nanoemulsion (AGO MNE) with a desirability value of 0.856 was subjected to further investigations for mucoadhesion, in vitro diffusion, transmission electron microscopy and in vivo biodistribution. It showed significantly successful distribution to the brain, the optimized AGO MNE intranasal gave a brain targeting efficiency (BTE) of 278.71% indicating increased drug brain targeting by the nasal route compared with the intravenous route. Additionally, the optimized AGO MNE by intranasal had a direct transport percentage (DTP) of 64.109%, which indicates a significant contribution of the direct nose-to-brain pathway in the brain drug delivery. The study proposed egg lecithin mucoadhesive nanoemulsion as a successful and promising strategy to directly and efficiently deliver drug to the brain.

Formulation, optimization and characterization of allantoin-loaded chitosan nanoparticles to alleviate ethanol-induced gastric ulcer: in-vitro and in-vivo studies.

Allantoin (ALL) is a phytochemical possessing an impressive array of biological activities. Nonetheless, developing a nanostructured delivery system targeted to augment the gastric antiulcerogenic activity of ALL has not been so far investigated. Consequently, in this survey, ALL-loaded chitosan/sodium tripolyphosphate nanoparticles (ALL-loaded CS/STPP NPs) were prepared by ionotropic gelation technique and thoroughly characterized. A full 24 factorial design was adopted using four independently controlled parameters (ICPs). Comprehensive characterization, in vitro evaluations as well as antiulcerogenic activity study against ethanol-induced gastric ulcer in rats of the optimized NPs formula were conducted. The optimized NPs formula, (CS (1.5% w/v), STPP (0.3% w/v), CS:STPP volume ratio (5:1), ALL amount (13 mg)), was the most convenient one with drug content of 6.26 mg, drug entrapment efficiency % of 48.12%, particle size of 508.3 nm, polydispersity index 0.29 and ζ-potential of + 35.70 mV. It displayed a sustained in vitro release profile and mucoadhesive strength of 45.55%. ALL-loaded CS/STPP NPs (F-9) provoked remarkable antiulcerogenic activity against ethanol-induced gastric ulceration in rats, which was accentuated by histopathological, immunohistochemical (IHC) and biochemical studies. In conclusion, the prepared ALL-loaded CS/STPP NPs could be presented to the phytomedicine field as an auspicious oral delivery system for gastric ulceration management.

Efficient fortification of folic acid in rice through ultrasonic treatment and absorption.

Folate deficiencies are prevalent in countries with insufficient food diversity. Rice fortification is seen as a viable way to improve the daily intake of folates. This work reports an efficient process of rice fortification involving ultrasonic treatment and absorption of the folic acid fortificant. Increased porosity due to sonication allowed the efficient absorption of folic acid into the brown rice kernel up to 5.195 × 104 µg/100 g, a 1,982-fold increase from its inherent content. The absorbed folic acid in brown rice has 93.53% retention after washing and cooking. Fortification of ultrasound-treated milled rice with folic acid was also efficient affording 6.559 × 104 µg/100 g, a 4,054-fold increase from its basal content. The effect of fortification caused a decrease in the thermal and pasting temperatures. The fortification also caused yellow coloration, decrease in hardness, and increase in the adhesiveness of the rice. The resulting fortified brown rice showed improved textural properties favorable for consumers.

Bioinspired Self-Healing Human-Machine Interactive Touch Pad with Pressure-Sensitive Adhesiveness on Targeted Substrates.

There is an increasing interest to develop a next generation of touch pads that require stretchability and biocompatibility to allow their integration with a human body, and even to mimic the self-healing behavior with fast functionality recovery upon damage. However, most touch pads are developed based on stiff and brittle electrodes with the lack of the important nature of self-healing. Polyzwitterion-clay nanocomposite hydrogels as a soft, stretchable, and transparent ionic conductor with transmittance of 98.8% and fracture strain beyond 1500% are developed, which can be used as a self-healing human-machine interactive touch pad with pressure-sensitive adhesiveness on target substrates. A surface-capacitive touch system is adopted to sense a touched position. Finger positions are perceived during both point-by-point touch and continuous moving. Hydrogel touch pads are adhered to curved or flat insulators, with the high-resolution and self-healable input functions demonstrated by drawing, writing, and playing electronic games.

Protective and regenerative effects of a novel medical device against esophageal mucosal damage using in vitro and ex vivo models.

Gastroesophageal reflux disease (GERD) is a common digestive disorder that causes esophagitis and injuries to the esophageal mucosa. GERD symptoms are recurrent during pregnancy and their treatment is focused on lifestyle changes and nonprescription medicines. The aim of this study was to characterize the mechanism of action of a new patented medical device, an oral formulation containing hyaluronic acid, rice extract, and amino acids dispersed in a bioadhesive polymer matrix, by assessing its protective effects in in vitro and ex vivo models of esophageal mucosa damage. Acidic bile salts and pepsin cocktail (BSC) added to CP-A and COLO-680 N esophagus cells were used as an in vitro GERD model to evaluate the binding capacities, anti-inflammatory effects and reparative properties of the investigational product (IP) in comparison to a viscous control. Our results showed that the IP prevents cell permeability and tight junction dysfunction induced by BSC. Furthermore, the IP was also able to down-regulate IL-6 and IL-8 mRNA expression induced by BSC stimulation and to promote tissue repair and wound healing. The results were confirmed by ex vivo experiments in excised rat esophagi through the quantification of Evans Blue permeability assay. These experiments provided evidence that the IP is able to bind to the human esophagus cells, preventing the damage caused by gastroesophageal reflux, showing potential anti-irritative, soothing, and reparative properties.

Statistical Considerations in Assessing In Vivo Adhesion with Transdermal and Topical Delivery Systems for New Drug Applications.

Proper adhesion plays a critical role in maintaining a consistent, efficacious, and safe drug delivery profile for transdermal and topical delivery systems (TDS). As such, in vivo skin adhesion studies are recommended by regulatory agencies to support the approval of TDS in new drug applications (NDAs). A draft guidance for industry by the US Food and Drug Administration outlines a non-inferiority comparison between a test product and its reference product for generic TDS in abbreviated new drug applications (ANDAs). However, the statistical method is not applicable for evaluating adhesion of TDS for NDAs, because no reference product exists. In this article, we explore an alternative primary endpoint and a one-sided binomial test to evaluate in vivo adhesion of TDS in NDAs. Statistical considerations related to the proposed approach are discussed. To understand its potential use, the proposed approach is applied to data sets of in vivo adhesion studies from selected NDAs and ANDAs.

Etoposide and olaparib polymer-coated nanoparticles within a bioadhesive sprayable hydrogel for post-surgical localised delivery to brain tumours.

Glioblastoma is a malignant brain tumour with a median survival of 14.6 months from diagnosis. Despite maximal surgical resection and concurrent chemoradiotherapy, reoccurrence is inevitable. To try combating the disease at a stage of low residual tumour burden immediately post-surgery, we propose a localised drug delivery system comprising of a spray device, bioadhesive hydrogel (pectin) and drug nanocrystals coated with polylactic acid-polyethylene glycol (NCPPs), to be administered directly into brain parenchyma adjacent to the surgical cavity. We have repurposed pectin for use within the brain, showing in vitro and in vivo biocompatibility, bio-adhesion to mammalian brain and gelling at physiological brain calcium concentrations. Etoposide and olaparib NCPPs with high drug loading have shown in vitro stability and drug release over 120 h. Pluronic F127 stabilised NCPPs to ensure successful spraying, as determined by dynamic light scattering and transmission electron microscopy. Successful delivery of Cy5-labelled NCPPs was demonstrated in a large ex vivo mammalian brain, with NCPP present in the tissue surrounding the resection cavity. Our data collectively demonstrates the pre-clinical development of a novel localised delivery device based on a sprayable hydrogel containing therapeutic NCPPs, amenable for translation to intracranial surgical resection models for the treatment of malignant brain tumours.

Quality Characteristics of Processed Cheese Fortified with Spirulina Powder.

BACKGROUND AND OBJECTIVE: Spirulina is a rich source of nutrients viz., essential amino acids, essential fatty acids, carotenoids and vitamins. The study was carried out to evaluate of Spirulina maxima addition as source of nutrients, antioxidants and color on processed cheese properties. MATERIALS AND METHODS: Processed cheese analogue treatments were supplemented with Spirulina maxima powder (1, 2 and 3%). The chemical, physical, color and sensorial properties of processed cheese analogue supplemented with S. maxima were evaluated through 3 months of cold storage (7°C). Also, the antioxidant capacity of S. maxima processed cheese analogue treatments was determined. RESULTS: The spreadable processed cheese analogue with 3% S. maxima powder had higher chemical components except ash compared to control cheese. The results of physical properties showed that the penetrometer reading of the S. maxima processed cheese treatments was higher than those of control allover storage period, while oil separation and melt ability were lower. The S. maxima processed cheeses were more green (a-value) and lower whiter (L-value) than those of control. The highest free radical scavenging activity (57.24%) was recorded for S. maxima processed cheese analogue treatment (3%). From the sensorial results, the S. maxima processed cheese analogue (1 or 2%) treatments was higher acceptable compared to those of 3%. CONCLUSION: Hence, adding S. maxima powder (1 or 2%) during processed cheese analogue manufacture let the cheese to develop special color (green), high nutritional value, antioxidant activity and sensorial scores.

Surface, adhesiveness and virulence aspects of Candida haemulonii species complex.

The emerging opportunistic pathogens comprising the Candida haemulonii complex (C. haemulonii [Ch], C. duobushaemulonii [Cd] and C. haemulonii var. vulnera[Chv]) are notable for their intrinsic antifungal resistance. Different clinical manifestations are associated with these fungal infections; however, little is known about their biology and potential virulence attributes. Herein, we evaluated some surface properties of 12 clinical isolates of Ch (n = 5), Cd (n = 4) and Chv (n = 3) as well as their virulence on murine macrophages and Galleria mellonella larvae. Scanning electron microscopy demonstrated the presence of homogeneous populations among the species of the C. haemulonii complex, represented by oval yeasts with surface irregularities able to form aggregates. Cell surface hydrophobicity was isolate-specific, exhibiting high (16.7%), moderate (25.0%) and low (58.3%) hydrophobicity. The isolates had negative surface charge, except for one. Mannose/glucose- and N-acetylglucosamine-containing glycoconjugates were evidenced in considerable amounts in all isolates; however, the surface expression of sialic acid was poorly detected. Cd isolates presented significantly higher amounts of chitin than Ch and Chv. Membrane sterol and lipid bodies, containing neutral lipids, were quite similar among all fungi studied. All isolates adhered to inert surfaces in the order: polystyrene > poly-L-lysine-coated glass > glass. Likewise, they interacted with murine macrophages in a quite similar way. Regarding in vivo virulence, the C. haemulonii species complex were able to kill at least 80% of the larvae after 120 hours. Our results evidenced the ability of C. haemulonii complex to produce potential surface-related virulence attributes, key components that actively participate in the infection process described in Candida spp.

Development, characterisation and nasal deposition of melatonin-loaded pectin/hypromellose microspheres.

In this study, we present the development of spray-dried pectin/hypromellose microspheres as efficient melatonin carrier for targeted nasal delivery. Different pectin to hypromellose weight ratios in the spray-dried feed were employed (i.e. 1:0, 3:1, 1:1 and 1:3) in order to optimise microsphere physicochemical properties influencing overall powder behaviour prior, during and upon nasal delivery. All microspheres assured complete melatonin entrapment and increased dissolution rate in relation to pure melatonin powder. Among all combinations tested, combining pectin with hypromellose at 1:3 wt ratio resulted in the microspheres with the highest potential for melatonin nasal delivery as they assured highest swelling ability and most prominent mucoadhesive properties. Studies on deposition profile revealed adequate turbinate and olfactory deposition of microsphere/lactose monohydrate powder blend administered nasally using MIAT® device, complementing findings relevant for their therapeutic potential. In conclusion, developed microspheres bear the potential to ensure prolonged melatonin retention at the nasal mucosa, improved bioavailability and advanced therapeutic outcome.

Mucoadhesive thin films for the simultaneous delivery of microbicide and anti-inflammatory drugs in the treatment of periodontal diseases.

There is an unmet clinical need for new products to address the high percentage of the populous who present with periodontal diseases. Drug dose retention at the point of application would facilitate sustained release and more efficacious treatments. The aim of this study was to evaluate mucoadhesive polymeric thin films for simultaneous in situ delivery chlorhexidine and anti-inflammatory and analgesic drugs. Mucoadhesive thin films were prepared using a polymer mixture containing chlorhexidine (25 mg) ± diclofenac sodium (10 and 50 mg), and lidocaine hydrochloride (10 mg) or betamethasone dipropionate (10 and 50 mg). The films were assessed for in vitro drug release and localised tissue delivery, followed by determination of modulated prostaglandin E2 (PGE2) levels in ex vivo tissue and cytotoxicity using a HaCaT keratinocyte cell line. Antibacterial activity of the chlorhexidine/diclofenac film was determined against planktonic and biofilm bacteria associated with periodontal disease and dental plaque. Chlorhexidine release was consistently low (up to 10% of initial loading) from all films, whereas the release of diclofenac, betamethasone and lidocaine exceeded 50% within 30 min. The 50 mg betamethasone film released up to 4-fold more than the 10 mg film. Statistically significant reduction of PGE2 was observed in ex vivo porcine gingival tissue for films containing chlorhexidine with or without diclofenac, and betamethasone. No cytotoxicity was observed for any film, apart from 50 mg betamethasone at 24 h. Films loaded with chlorhexidine and diclofenac were inhibitory against relevant test bacteria. Between 3 and 6 log10 reductions in bacterial cell recovery was observed after biofilm exposure to the chlorhexidine films irrespective of the presence of the anti-inflammatory or anaesthetic. This work demonstrated that thin film formulations have the potential to simultaneously counter key causative factors in periodontal diseases, namely associated bacteria biofilm and chronic local inflammation.