New prospective in treatment of Parkinson's disease: Studies on permeation of ropinirole through buccal mucosa

Fabricating Polymer/Surfactant/Cyclodextrin Hybrid Particles for Possible Nose-to-Brain Delivery of Ropinirole Hydrochloride: In Vitro and Ex Vivo Evaluation

Ropinirole is a non-ergolinic dopamine agonist used to manage Parkinson's disease and it is characterized by poor oral bioavailability. This study aimed to design and develop advanced drug delivery systems composed of poloxamer 407, a non-ionic surfactant (Tween 80), and cyclodextrins (methyl-β-CD or hydroxy-propyl-β-CD) for possible brain targeting of ropinirole after nasal administration for the treatment of Parkinson's disease. The hybrid systems were formed by the thin-film hydration method, followed by an extensive physicochemical and morphological characterization. The in vitro cytotoxicity of the systems on HEK293 cell lines was also tested. In vitro release and ex vivo mucosal permeation of ropinirole were assessed using Franz cells at 34 °C and with phosphate buffer solution at pH 5.6 in the donor compartment, simulating the conditions of the nasal cavity. The results indicated that the diffusion-controlled drug release exhibited a progressive increase throughout the experiment, while a proof-of-concept experiment on ex vivo permeation through rabbit nasal mucosa revealed a better performance of the prepared hybrid systems in comparison to ropinirole solution. The encouraging results in drug release and mucosal permeation indicate that these hybrid systems can serve as attractive platforms for effective and targeted nose-to-brain delivery of ropinirole with a possible application in Parkinson's disease. Further ex vivo and in vivo studies to support the results of the present work are ongoing.

Buccal Thin Films as Potent Permeation Enhancers for Cytisine Transbuccal Delivery

Cytisine (CYT) is a powerful anti-smoking compound which could greatly benefit from transbuccal delivery because of both its unfavorable pharmacokinetics after oral administration and its intrinsic ability to permeate the buccal mucosa. This work aims to design CYT-loaded buccal thin films suitable for transbuccal drug delivery due to its capability of promoting the interaction between CYT and the buccal membrane. The solvent casting method was employed to prepare several thin films combining various excipients such as matrixing polymers, mucoadhesion agents, plasticizers and other compounds as humectants and sweeteners, component ratios and solvents. A total of 36 compositions was prepared and four of them emerged as the most promising in terms of aspect and flexibility. They all demonstrated homogeneity, thinness, low swelling degree, and controlled drug release according to the Power Law and Peppas-Sahlin mathematical models. Mainly, they proved able to interact with the ex vivo porcine buccal mucosa producing mucoadhesive effects, and act as potent permeation enhancers. In particular, Film B emerged as suitable as it produced a 10.6-fold Kp enhancement and a great Js value (52.33 μg/cm²·h^-1), even when compared to highly concentrated CYT solutions.

Spray-Dried Cytisine-Loaded Matrices: Development of Transbuccal Sustained-Release Tablets as a Promising Tool in Smoking Cessation Therapy

Cytisine (CYT) has emerged as a promising molecule to treat nicotine addiction, since it acts as a partial agonist of nicotinic acetylcholine receptors. However, its unfavorable pharmacokinetic properties lead to multiple administrations per day, reducing the patient’s compliance and increasing the side effects. To overcome these drawbacks, CYT buccal administration is here proposed. Firstly, CYT stability in the buccal environment was assessed and its intrinsic ability to permeate/penetrate the tissue was determined by applying CYT solutions at increasing concentrations. Furthermore, a spray-drying method was selected and optimized as it is an eco-friendly, easily scalable and effective technique to obtain uniform and reproducible CYT-loaded (5% w/w) pharmaceutical powders, which were directly compressed, thus obtaining different buccal delivery systems (BDSs). The obtained BDSs were homogeneous and reproducible and embedded CYT in its amorphous form. The mechanism of CYT release was evaluated in vitro and found to be mainly driven by a Fickian diffusion phenomenon. Predominantly, the ex vivo permeation assays highlighted the ability of the BDSs to enhance CYT permeation, also producing high drug fluxes through the mucosa. Speculative mathematical evaluations based on the already-known CYT pharmacokinetic parameters showed that CYT-loaded BDSs could potentially be sufficient to obtain a therapeutic effect, thus making the reported formulations suitable candidates for further in vivo trials.

Recent Advancements and Patents on Buccal Drug Delivery Systems: A Comprehensive Review

The major requirement for a dosage form to be successful is its ability to penetrate the site of application and the bioavailability of the drug released from the dosage form. The buccal drug delivery is an influential route to deliver the drug into the body. Here, in this context, various novel approaches that include lipoidal carriers like ethosomes, transferosomes, niosomes etc. and electrospun nanofibers are discussed, with respect to buccal drug delivery. These carriers can be easily incorporated into buccal dosage forms like patches and gels that are responsible for increased permeation across the buccal epithelium. The in vivo methods of evaluation on animal models are conscribed here. The novel biocarriers of lipoidal and non-lipoidal nature can be utilized by loading the drug into them, which are helpful in preventing drug degradation and other drawbacks as compared to conventional formulations. The globally patented buccal formulations give us a wide context in literature about the patents filed and granted in the recent years. When it comes to patient compliance, age is an issue, which is also solved by the buccal route. The pediatric buccal formulations are researched for the customization to be delivered to children. Diseases like mouth ulcers, oral cancer, Parkinson's disease, aphthous stomatitis etc. have been successfully treated through the buccal route, which infers that the buccal drug delivery system is an effective and emerging area for formulation and development in the field of pharmaceutics.

Lipid Nanocarriers-Loaded Nanocomposite as a Suitable Platform to Release Antibacterial and Antioxidant Agents for Immediate Dental Implant Placement Restorative Treatment

Immediate implant placement is a single-stage restorative approach for missing teeth widely used to overcome the ridge remodeling process occurring after dental extractions. The success of this procedure relies on opportune osseointegration in the surrounding tissues. To support this process, a multifunctional nanocomposite, to be applied in the fresh post-extraction socket, was here designed, prepared, and characterized. This formulation consists of quercetin (QRC)-loaded nanostructured lipid carriers (NLCs) entrapped in a chitosan-based solid matrix containing ciprofloxacin (CPX). QRC-NLCs were prepared by homogenization followed by high-frequency sonication, and thereafter this dispersion was trapped in a chitosan-based CPX-loaded gel, obtaining the nanocomposite powder (BioQ-CPX) by lyophilization. BioQ-CPX displayed desirable properties such as high porosity (94.1 ± 0.5%), drug amounts (2.1% QRC and 3.5% CPX). and low swelling index (100%). Moreover, the mechanism of drug release from BioQ-CPX and their ability to be accumulated in the target tissue were in vitro and ex vivo elucidated, also by applying mathematical models. When trapped into the nanocomposite, QRC stressed under UV light exposure (50 W) was shown to maintain its antioxidant power, and CPX and QRC under natural light were stable over nine months. Finally, both the measured antioxidant power and the antimicrobial and antibiofilm properties on Staphylococcus aureus demonstrated that BioQ-CPX could be a promising platform to support the single-stage dental restorative treatment.

Improvement of Resveratrol Permeation through Sublingual Mucosa: Chemical Permeation Enhancers versus Spray Drying Technique to Obtain Fast-Disintegrating Sublingual Mini-Tablets

Resveratrol (RSV) is a natural polyphenol with several interesting broad-spectrum pharmacological properties. However, it is characterized by poor oral bioavailability, extensive first-pass effect metabolism and low stability. Indeed, RSV could benefit from the advantage of the sublingual route of administration. In this view, RSV attitudes to crossing the porcine sublingual mucosa were evaluated and promoted both by six different chemical permeation enhancers (CPEs) as well as by preparing four innovative fast-disintegrating sublingual mini-tablets by spray drying followed by direct compression. Since RSV by itself exhibits a low permeation aptitude, this could be significantly enhanced by the use of CPEs as well as by embedding RSV in a spray-dried powder to be compressed in order to prepare fast-disintegrating mini-tablets. The most promising observed CPEs (menthol, lysine and urea) were then inserted into the most promising spray-dried excipients’ compositions (RSV-B and RSV-C), thus preparing CPE-loaded mini-tablets. However, this procedure leads to unsatisfactory results which preclude the possibility of merging the two proposed approaches. Finally, the best spray-dried composition (RSV-B) was further evaluated by SEM, FTIR, XRD and disintegration as well as dissolution behavior to prove its effectiveness as a sublingual fast-disintegrating formulation.

Solid and Semisolid Innovative Formulations Containing Miconazole-Loaded Solid Lipid Microparticles to Promote Drug Entrapment into the Buccal Mucosa

The currently available antifungal therapy for oral candidiasis (OC) has various limitations restricting its clinical use, such as short retention time, suboptimal drug concentration and low patients compliance. These issues could be overcome using micro or nanotechnology. In particular, solid lipid microparticles (SLMs) resulted as a particularly promising penetration enhancer carrier for lipophilic drugs, such as the antifungal miconazole (MCZ). Based on these considerations, cetyl decanoate (here synthesized without the use of metal catalysis) was employed together with 1-hexadecanol to prepare MCZ-loaded SLMs. These resulted in a powder composed of 45–300 µm diameter solid spherical particles, able to load a high amount of MCZ in the amorphous form and characterized by a melting temperature range perfectly compatible with oromucosal administration (35–37 °C). Moreover, when compared to Daktarin^® 2% oral gel in ex vivo experiments, SLMs were able to increase up to three-fold MCZ accumulation into the porcine buccal mucosa. The prepared SLMs were then loaded into a buccal gel or a microcomposite mucoadhesive buccal film and evaluated in terms of MCZ permeation and/or accumulation into porcine buccal mucosa by using lower doses than the conventional dosage form. The promising results obtained highlighted an enhancement in terms of MCZ accumulation even at low doses. Furthermore, the prepared buccal film was eligible as stable, reproducible and also highly mucoadhesive. Therefore, the formulated SLMs represent a penetration enhancer vehicle suitable to reduce the dose of lipophilic drugs to be administered to achieve the desired therapeutic effects, as well as being able to be effectively embedded into easily administrable solid or semisolid dosage forms.

The potential of ODFs as carriers for drugs/vaccines against COVID-19

COVID-19 has spread out its wings across the globe and is taking away many lives. Millions of people are (self) quarantined to prevent the spread of this viral disease. World Health Organization (WHO) has affirmed that there is not any medicine for COVID-19. Besides, there is also no single drug that is approved by any regulatory agency for usage against this dangerous disease. Researchers across the globe are working tirelessly to fix an end to this virus and to save precious lives. While the research is in full swing, one is not sure whether they would come up with a chemical/herbal drug or a vaccine. Irrespective of the type of active ingredient for COVID-19, one needs to have a proper system to deliver the identified active ingredient to subjects/patients across the globe. Orodispersible films (ODFs) are excellent and attractive drug delivery carriers that have the potential to deliver drugs, herbal extracts, and vaccines. They are apt for patients who have a problem consuming traditional drug products such as tablets or capsules. The beauty of this dosage form is that it does not need water to consume by the subjects and can be readily administered to the tongue. The present review highlights the true potential of ODFs to act as a carrier for the delivery of various antiviral drugs/herbs/vaccines.

Amorphous Ropinirole-Loaded Mucoadhesive Buccal Film: A Potential Patient-Friendly Tool to Improve Drug Pharmacokinetic Profile and Effectiveness

Nowadays the therapeutic strategies to manage Parkinson’s Disease are merely symptomatic and consist of administering L-DOPA and/or dopamine receptor agonists. Among these, Ropinirole (ROP) is a widely orally-administered molecule, although it is extensively susceptible to hepatic metabolism. Since literature reports the buccal mucosa as a potentially useful route to ROP administration, the development of novel, effective, and comfortable oromucosal formulations should prove desirable in order to both enhance the therapeutic efficacy of the drug and allow a personalized therapeutic strategy able to meet the patient’s needs. The results of the proposed ROP film as a new dosage form show that it is flexible; uniform; and characterized by suitable surface pH; good mucoadhesiveness; low swelling degree; and fast, complete drug release. Moreover, after ex vivo evaluation on a film having an area of 0.282 cm² and dose of 2.29 mg, the results of drug flux through the buccal mucosa are closely comparable to the amount of ROP that reaches the bloodstream at the steady-state condition after ROP-PR 4 mg oral administration, calculated according to the literature (0.237 mg/cm²·h⁻¹ vs. 0.243 mg/h, respectively). Moreover, drug flux and ROP dose could be accurately modulated time-by-time depending on the patient’s need, by varying the administered disk area. In addition, the proposed ROP film displays no lag time, producing an immediate drug input in the bloodstream, which could result in a prompt therapeutic response. These findings make ROP film a potentially comfortable and patient-friendly formulation, and a promising candidate for further clinical trials.

Bilayer mucoadhesive buccal films with prolonged release of ciclopirox olamine for the treatment of oral candidiasis: In vitro development, ex vivo permeation testing, pharmacokinetic and efficacy study in rabbits

The incidence of fungal infections has increased in recent decades not only in patients with predisposing and risk factors, but it has also spread up due to the widespread use of broad-spectrum antibiotics, immunosuppressants and corticosteroids. A limited number of drugs are currently used to treat oral candidiasis (OC). There is an emerging need to look for new antifungals, to rework or to explore the already known molecules. Ciclopirox olamine (CPX), a broad-spectrum antifungal agent, is currently used for topical dermatologic treatment. In this study, bilayer mucoadhesive buccal films (MBFs) containing poly(ethylene oxide) (PEO) and Eudragit® NM 30D (EU) with the prolonged release of ciclopirox olamine, were developed for the treatment of oral candidiasis. During ex vivo testing it was found that CPX does not pass through the porcine buccal tissue but it accumulates in it, which may be beneficial for the treatment of candidiasis in the oral cavity. In a pharmacokinetic study, the drug release from mucoadhesive films was prolonged with the maximum plasma concentration at 3.4 (1.4; 5.5) h. All rabbits with stomatitis showed progressive healing after the treatment with CPX bilayer mucoadhesive buccal films without organ pathologies.

Development of a Multifunctional Bioerodible Nanocomposite Containing Metronidazole and Curcumin to Apply on L-PRF Clot to Promote Tissue Regeneration in Dentistry

Teeth extractions are often followed by alveolar bone reabsorption, although an adequate level of bone is required for reliable rehabilitations by dental implants. Leukocyte and platelet-rich fibrin (L-PRF) has been widely applied in regenerative procedures and with antibiotic and antioxidant agents could play an essential role in hard and soft tissue healing. In this work, a nanocomposite (Sponge-C-MTR) consisting of a hyaluronate-based sponge loaded with metronidazole (MTR) and nanostructured lipid carriers containing curcumin (CUR-NLC) was designed to be wrapped in the L-PRF™ membrane in the post-extraction sockets and characterized. CUR-NLCs, obtained by homogenization followed by high-frequency sonication of the lipid mixture, showed loading capacity (5% w/w), drug recovery (95% w/w), spherical shape with an average particle size of 112.0 nm, and Zeta potential of -24 mV. Sponge-C-MTR was obtained by entrapping CUR-NLC in a hydrophilic matrix by a freeze-drying process, and physico-chemical and cytocompatibility properties were evaluated. Moreover, the aptitude of CUR and MTR to the penetrate and/or permeate both L-PRF™ and porcine buccal tissue was assessed, highlighting MTR penetration and CUR accumulation promoted by the system. The results positively support the action of nanocomposite in dental tissues regeneration when applied together with the L-PRF™.

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.

Transbuccal delivery of benznidazole associated with monoterpenes: permeation studies and mechanistic insights

Benznidazole (BZN) represents the only drug currently available for the treatment of Chagas disease in most endemic countries. When administered orally, high doses are required due to its extensive hepatic metabolism and its toxicity represents the main reason for treatment withdrawals. Because of these complications, transbuccal administration of BZN was investigated. This route avoids the first-pass hepatic metabolism and presents high permeability, with direct access to the systemic circulation. BZN was applied on porcine buccal mucosa after pretreatment with pure eugenol, carvacrol or limonene. Thermal (DSC) and spectroscopic (FT-IR) analyzes were performed to investigate the mechanisms of drug absorption enhancement. The permeability coefficient values of BZN increased 2.6, 2.9 and 4.9-fold after pretreatment with eugenol, carvacrol and limonene, respectively. The lag time, in turn, was shortened in the pretreated samples. The DSC and FT-IR analyzes suggested that transport of BZN through the buccal mucosa is associated with log P and size of monoterpenes. Limonene, the most effective absorption enhancer, contributed to greater interaction with non-polar domains of the buccal epithelium. Overall, BZN showed to be efficiently transported through the buccal route, but in vivo pharmacokinetic studies should be performed to confirm these findings.

Bioadhesive Matrix Tablets Loaded with Lipophilic Nanoparticles as Vehicles for Drugs for Periodontitis Treatment: Development and Characterization

Periodontitis treatment is usually focused on the reduction or eradication of periodontal pathogens using antibiotics against anaerobic bacteria, such as metronidazole (MTR). Moreover, recently the correlation between periodontal diseases and overexpression of reactive oxygen species (ROS) led to the introduction of antioxidant biomolecules in therapy. In this work, bioadhesive buccal tablets, consisting of a hydrophilic matrix loaded with metronidazole and lipophilic nanoparticles as a vehicle of curcumin, were developed. Curcumin (CUR)-loaded nanostructured lipid carriers (NLC) were prepared using glycyrrhetic acid, hexadecanol, isopropyl palmitate and Tween®80 as a surfactant. As method, homogenization followed by high-frequency sonication was used. After dialysis, CUR-NLC dispersion was evaluated in terms of drug loading (DL, 2.2% w/w) and drug recovery (DR, 88% w/w). NLC, characterized by dynamic light scattering and scanning electron microscopy (SEM), exhibited a spherical shape, an average particle size of 121.6 nm and PDI and PZ values considered optimal for a colloidal nanoparticle dispersion indicating good stability of the system. Subsequently, a hydrophilic sponge was obtained by lyophilization of a gel based on trehalose, Natrosol and PVP-K90, loaded with CUR-NLC and MTR. By compression of the sponge, matrix tablets were obtained and characterized in term of porosity, swelling index, mucoadhesion and drugs release. The ability of the matrix tablets to release CUR and MTR when applied on buccal mucosa and the aptitude of actives to penetrate and/or permeate the tissue were evaluated. The data demonstrate the ability of NLC to promote the penetration of CUR into the lipophilic domains of the mucosal membrane, while MTR can penetrate and permeate the mucosal tissue, where it can perform a loco-regional antibacterial activity. These results strongly support the possibility of using this novel matrix tablet for delivering MTR together with CUR for topical treatment of periodontal diseases.

Quality, functional and sensory evaluation of pasta fortified with extracts from Opuntia ficus-indica cladodes

BACKGROUND

The stems of Opuntia ficus-indica, known as cladodes, are a rich source of soluble fibers, which makes them an important candidate for the production of functional foods. Tagliatelle of durum wheat fortified with Opuntia cladode extract (OCE) at different levels of addition (10-30%, v/w) was prepared on a laboratory scale and quality characteristics and sensory acceptability were assessed.

RESULTS

The main quality parameters (optimal cooking time, swelling index, cooking loss, dry matter) and sensory analysis on a nine-point hedonic scale were comparable with those of the control pasta sample (no added OCE) when durum wheat was supplemented with OCE at up to 20% (v/w). An in vitro human simulated gastrointestinal digestion in the presence of cholesterol or its main dietary oxidized derivative, 7-ketocholesterol, showed that OCE-fortified pasta strongly reduced the bioaccessibility of both the sterols (the higher the incorporated OCE level, the higher the effect). Moreover the extent of starch digestion decreased with increasing levels of OCE.

CONCLUSION

The results of the present study indicate that OCE-fortified pasta comprises a food with healthy properties, such as blood cholesterol- and glucose-lowering capabilities. © 2019 Society of Chemical Industry.

Enhanced In Situ Availability of Aphanizomenon Flos-Aquae Constituents Entrapped in Buccal Films for the Treatment of Oxidative Stress-Related Oral Diseases: Biomechanical Characterization and In Vitro/Ex Vivo Evaluation

In recent years, the key role of oxidative stress in pathogenesis of oral diseases has been emphasized and the use of antioxidant agents has been encouraged. Aphanizomenon flos-aquae (AFA) is a unicellular blue-green alga with antioxidant and anti-inflammatory properties. The aim of this study was the formulation and characterization of mucoadhesive thin layer films loaded with AFA, finalized to the treatment of oxidative stress (OS)-related oral diseases. First, to enhance the bioavailability of AFA constituents, the raw food grade material was appropriately treated by a high frequency homogenization able to disrupt cell walls. Thus, Eudragit^® E100-based buccal films were produced by the solvent casting method, containing 7% and 18% of AFA. The films, characterized by uniformity in thickness, weight, and drug content, showed low swelling degree, good muco-adhesiveness and controlled drug release. The mechanical tests showed elastic moduli of films of almost 5 MPa that is well-suitable for human buccal applications without discomfort, besides biaxial tests highlighted a marked material isotropy. Permeation studies through porcine mucosae demonstrated the ability of films to promote AFA penetration in the tissues, and when sublingually administered, they produced a drug flux up to six-fold higher than an AFA solution. The new formulations represent an interesting alternative for the development of cosmetics and nutraceuticals with a functional appeal containing plant extracts.

Mucoadhesive Polymeric Films to Enhance Barbaloin Penetration Into Buccal Mucosa: a Novel Approach to Chemoprevention

Nowadays, chemoprevention by administering natural supplements is considered an attractive strategy to reverse, suppress, or prevent the evolution of premalignant oral lesions. In particular, Barbaloin exhibits anti-proliferative, anti-inflammatory, and anti-cancer properties, and it results useful in multi-therapy with classic chemotherapeutics. Therefore, in this work, mucoadhesive buccal films, as locoregional drug delivery system able to provide a targeted and efficient therapeutic delivery of Barbaloin, are proposed. Thus, Aloin extract-loaded Eudragit® RL100 or Eudragit® RS100-based buccal films were designed in order to obtain an easily self-administrable formulation capable of promoting Barbaloin penetration into buccal mucosa and assuring high patient compliance. Large amounts of extract (44%) were loaded into the polymer matrix and six formulations were prepared varying polymers and plasticizers ratios. For all formulations, physical form (thermogravimetric analysis-differential scanning calorimetry, TGA-DSC), swelling degree, mucoadhesiveness, drug release, and ability to promote drug penetration in mucosa have been investigated. After a sequential selection process, Eudragit RS 100-based film, with low PVP and high plasticizers amounts, emerged as the most promising. It results appropriately flexible, uniform in terms of weight, thickness and drug content, as well as characterized by suitable surface pH, good mucoadhesiveness, and low swelling degree. It displays a Higuchian drug release behavior up to 89% of Barbaloin released, thus demonstrating that diffusion through the matrix is the main release mechanism. Remarkable penetration enhancer properties of film were demonstrated by evidence of Barbaloin accumulation into buccal mucosa up to 10-fold higher than those obtained following administration of Aloin solution.

Development and Characterization of an Amorphous Solid Dispersion of Furosemide in the Form of a Sublingual Bioadhesive Film to Enhance Bioavailability

Administered by an oral route, Furosemide (FUR), a diuretic used in several edematous states and hypertension, presents bioavailability problems, reported as a consequence of an erratic gastrointestinal absorption due to various existing polymorphic forms and low and pH-dependent solubility. A mucoadhesive sublingual fast-dissolving FUR based film has been developed and evaluated in order to optimize the bioavailability of FUR by increasing solubility and guaranteeing a good dissolution reproducibility. The Differential Scanning Calorimetry (DSC) analyses confirmed that the film prepared using the solvent casting method entrapped FUR in the amorphous state. As a solid dispersion, FUR increases its solubility up to 28.36 mg/mL. Drug content, thickness, and weight uniformity of film were also evaluated. The measured Young's Modulus, yield strength, and relative elongation of break percentage (EB%) allowed for the classification of the drug-loaded film as an elastomer. Mucoadhesive strength tests showed that the force to detach film from mucosa grew exponentially with increasing contact time up to 7667 N/m². FUR was quickly discharged from the film following a trend well fitted with the Weibull kinetic model. When applied on sublingual mucosa, the new formulation produced a massive drug flux in the systemic compartment. Overall, the proposed sublingual film enhances drug solubility and absorption, allowing for the prediction of a rapid onset of action and reproducible bioavailability in its clinical application.

LC–MS/MS assay of ropinirole in rat biological matrices: elimination of lysoglycerophosphocholines-based matrix effect

Aim: To adequately support PK evaluation of ropinirole in rats following intranasal administration, it was desirable to determine ropinirole concentrations in rat plasma, brain homogenate and microdialysate. Results & methodology: A robust LC–MS/MS method has been developed for the determination of ropinirole in biological samples. Liquid–liquid extraction using ethyl acetate eliminated matrix effect due to significantly reduced levels of lysoglycerophosphocholines. The assay was fully validated with dynamic ranges of 0.01–20 ng/ml for plasma and brain homogenate samples and 0.1–200 ng/ml for microdialysate samples. Conclusion: The proposed method was accurate and precise for the quantification of ropinirole in biological samples and was successfully applied to a microdialysis study of ropinirole in rats.

Aloin delivery on buccal mucosa: ex vivo studies and design of a new locoregional dosing system

CONTEXT

Chemoprevention of potential malignant disorders or cancerous lesions that affect oral mucosae requires extended duration of treatment. Locoregional delivery of natural products could represent a promising strategy for this purpose.

OBJECTIVE

To investigate the aptitude of aloin to permeate through, or accumulate in, the buccal mucosa and to develop a new prolonged oro-mucosal drug delivery system.

MATERIALS AND METHODS

Permeation/accumulation of aloin from Curacao Aloe (containing 50% barbaloin) was evaluated ex vivo, using porcine buccal mucosa as the most useful model to simulate human epithelium. Oro-mucosal matrix tablets were prepared by dispersing aloin (10% w/w) in Eudragit® RS 100 as, biocompatible, low permeable, pH-independent, and non-swelling polymer. The prepared tablets were evaluated for drug-polymer compatibility, weight variation, drug uniformity content, diameter, thickness, hardness, friability, swelling, mucoadhesive strength, and drug release.

RESULTS

Aloin has low tendency to cross buccal mucosa, permeation is marginal, and high drug amounts remain entrapped into the epithelium. Matrix tablets characteristics were in agreement with pharmacopoeial requirements. Drug release showed highly reproducible Higuchian profile. Delivery through matrix tablets promoted drug accumulation in the mucosal tissue.

DISCUSSION AND CONCLUSION

Following application of matrix tablets on porcine buccal mucosa, the amount of discharged drug recovered in the tissue should be sufficient to produce the desired effects, providing therapeutic drug levels directly at the site of action. Aloin-loaded tablets are valid candidates for prevention/treatment of potentially malignant disorders and oral cancer and could potentially lead to clinically relevant drug delivery system as coadjuvant of conventional chemotherapy/radiation therapy.

Oral transmucosal drug delivery--current status and future prospects

Oral transmucosal drug delivery (OTDD) dosage forms have been available since the 1980s. In contrast to the number of actives currently delivered locally to the oral cavity, the number delivered as buccal or sublingual formulations remains relatively low. This is surprising in view of the advantages associated with OTDD, compared with conventional oral drug delivery. This review examines a number of aspects related to OTDD including the anatomy of the oral cavity, models currently used to study OTDD, as well as commercially available formulations and emerging technologies. The limitations of current methodologies to study OTDD are considered as well as recent publications and new approaches which have advanced our understanding of this route of drug delivery.

Dopamine receptor agonists for Parkinson's disease

INTRODUCTION

Prolonged administration of l-3,4-dihydroxyphenylalanine (l-DOPA) for Parkinson's disease (PD) is hampered by motor complications related to the progressive incapacity of residual nigrostriatal neurons to properly utilize the drug. Direct stimulation of dopaminergic (DAergic) receptors with specific compounds (DA agonists) has, therefore, become an additional therapeutic tool for PD.

AREAS COVERED

DA agonists have considerable anti-parkinsonian symptomatic efficacy, although they are less potent than l-DOPA. This review summarizes pre-clinical and clinical data on DA agonists and their role in treating PD. Specific focus was put on second-generation, first-line non-ergolinic DA agonists and their motor, non-motor and putative neuroprotective effects. The anti-parkinsonian potential of recently developed DA agonists that reached Phase II and III clinical trials was also addressed.

EXPERT OPINION

DA agonists can be useful along the whole natural course of PD, as monotherapy in the initial phase or combined with l-DOPA in advanced PD. Extended-release formulations have been developed for second-generation DA agonists, which are better appreciated by patients. Neuroprotective properties have been proposed for DA agonists, based on pre-clinical studies, but never convincingly demonstrated in patients. New DA agonists, with better symptomatic efficacy and devoid of the side effects that characterize current compounds, are needed.

Novel surface modified polymer-lipid hybrid nanoparticles as intranasal carriers for ropinirole hydrochloride: in vitro, ex vivo and in vivo pharmacodynamic evaluation

Here we report fabrication and evaluation of novel surface modified polymer-lipid hybrid nanoparticles (PLN) as robust carriers for intranasal delivery of ropinirole hydrochloride (ROPI HCl). Sustained release, avoidance of hepatic first pass metabolism, and improved therapeutic efficacy are the major objectives of this experiment. PLN were fabricated by emulsification-solvent diffusion technique and evaluated for physicochemical parameters, in vitro mucoadhesion, in vitro diffusion, ex vivo permeation, mucosal toxicity and stability studies. Box-Behnken experimental design approach has been employed to assess the influence of two independent variables, viz. surfactant (Pluronic F-68) and charge modifier (stearylamine) concentration on particle size, ζ-potential and entrapment efficiency of prepared PLN. Numerical optimization techniques were used for selecting optimized formulation sample, further confirmed by three dimensional response surface plots and regression equations. Results of ANOVA demonstrated the significance of suggested models. DSC and SEM analysis revealed the encapsulation of amorphous form of drug into PLN system, and spherical shape. PLN formulation had shown good retention with no severe signs of damage on integrity of nasal mucosa. Release pattern of drug-loaded sample was best fitted to zero order kinetic model with non-Fickian super case II diffusion mechanism. In vivo pharmacodynamic studies were executed to compare therapeutic efficacy of prepared nasal PLN formulation against marketed oral formulation of same drug. In summary, the PLN could be potentially used as safe and stable carrier for intranasal delivery of ROPI HCl, especially in treatment of Parkinson's disease.