The Evolution of Emerging Nanovesicle Technologies for Enhanced Delivery of Molecules into and across the Skin.

This review focuses on nanovesicular carriers for enhanced delivery of molecules into and across the skin, from their design to recent emerging technologies. During the last four decades, several approaches have been used aiming to design new nanovesicles, some of them by altering the properties of the classic phospholipid vesicle, the liposome. Phospholipid nanovesicular systems, including the phospholipid soft vesicles as well as the non-phospholipid vesicular carries, are reviewed. The altered nanovesicles have served in the manufacture of various cosmetic products and have been investigated and used for the treatment of a wide variety of skin conditions. The evolution and recent advances of these nanovesicular technologies are highlighted in this review.

Evaluation of nasal delivery systems of olanzapine by desorption electrospray ionization mass spectrometry imaging.

Nose-to-brain delivery presents an attractive administration route for neuroactive drugs that suffer from compromised bioavailability or fail to pass the blood-brain barrier. However, the conventional gauge of effectiveness for intranasal delivery platforms primarily involves detecting the presence of the administered drug within the brain, with little insight into its precise localization within brain structures. This may undermine the therapeutic efficacy of drugs and hinder the design of systems that target specific brain regions. In this study, we designed two intranasal delivery systems for the antipsychotic drug, olanzapine, and evaluated its distribution in the rat brain following intranasal administration. The first evaluated system was an olanzapine-loaded microemulsion and the second one was nanoparticulate aqueous dispersion of olanzapine. Both systems exhibited characteristics that render them compatible for intranasal administration, and successfully delivered olanzapine to the brain. We further employed an ambient mass spectrometry imaging method, called desorption electrospray ionization mass spectrometry imaging, to visualize the signal intensity of olanzapine in different brain regions following the intranasal administration of these two systems. Substantial variations in the distribution patterns of olanzapine across various brain structures were revealed, potentially highlighting the importance of mass spectrometry imaging in designing and evaluating intranasal drug delivery platforms.

Film Forming Systems for Delivery of Active Molecules into and across the Skin.

We have investigated delivery systems that can form a structured matrix film on the skin after their application. In a previous work, we have shown that Weblike film forming systems (also called Pouches Drug Delivery Systems, PDDS) enable enhanced skin delivery of the incorporated molecules. These delivery systems are composed of one or more phospholipids, a short-chain alcohol, a polymer and optionally water. In this work, we continue the investigation and characterization of Weblike carriers focusing on some factors affecting the delivery properties such as components concentration and mode of application on the skin. Upon non-occluded application on the skin, the systems dry rapidly, forming a web-like structured film. Lidocaine, Ibuprofen, FITC and Cannabidiol are molecules with various physico-chemical properties that were incorporated in the carrier. The systems were tested in a number of in vitro and in vivo experiments. Results of the in vitro permeation of Ibuprofen through porcine skin indicated two-fold delivery through the skin of Ibuprofen when applied from our Weblike system in comparison with a nanovesicular carrier, the ethosome. We also have investigated weblike systems containing hemp seed oil (HSO). This addition enhanced the film's ability to deliver lipophilic molecules to the deeper skin layers, leading to an improved pharmacodynamic effect. In analgesic tests carried out in a pain mice model following one hour application of CBD in Weblike system with and without HSO, the number of writhing episodes was decreased from 29 in the untreated animals to 9.5 and 18.5 writhes, respectively. The results of our work open the way towards a further investigation of Weblike film forming systems containing drugs for improved dermal and transdermal treatment of various ailments.

Improved Efficiency of Pomegranate Seed Oil Administrated Nasally.

Pomegranate seed oil (PSO) is currently administrated orally as a food supplement for improving memory. However, the efficiency of the oral dosage forms for such purposes is low, mainly due to the blood brain barrier impeding a good delivery to brain. In this work, we designed and characterized a PSO phospholipid oily gel for nasal administration. We tested the performance of the new PSO delivery system in animal models for impaired memory and locomotor activity. The experimental results indicated a statistically significant improvement (p < 0.05) of more than 1.5 fold in the behavior of animals treated nasally, in comparison to those treated with orally administrated oil. Furthermore, in multiphoton microscopy and near infrared imaging studies, the nasal administration of fluorescent probes, fluorescein isothiocyanate (FITC), and indocyanine green (ICG) incorporated in the PSO system showed enhanced delivery to the brain. Results of the histopathologic examination of the nasal cavity and mucosa, as carried out by a pathologist, indicated the safety of the PSO phospholipid oily gel. In conclusion, the results of this work encourage further investigation of the phospholipid oily gel composition as a new way of PSO administration.

Topical Administration of Drugs Incorporated in Carriers Containing Phospholipid Soft Vesicles for the Treatment of Skin Medical Conditions.

This review focuses on the improved topical treatment of various medical skin conditions by the use of drugs delivered from carriers containing phospholipid soft vesicles. Topical drug delivery has many advantages over other ways of administration, having increased patient compliance, avoiding the first-pass effect following oral drug administration or not requesting multiple doses administration. However, the skin barrier prevents the access of the applied drug, affecting its therapeutic activity. Carriers containing phospholipid soft vesicles are a new approach to enhance drug delivery into the skin and to improve the treatment outcome. These vesicles contain molecules that have the property to fluidize the phospholipid bilayers generating the soft vesicle and allowing it to penetrate into the deep skin layers. Ethosomes, glycerosomes and transethosomes are soft vesicles containing ethanol, glycerol or a mixture of ethanol and a surfactant, respectively. We review a large number of publications on the research carried out in vitro, in vivo in animal models and in humans in clinical studies, with compositions containing various active molecules for treatment of skin medical conditions including skin infections, skin inflammation, psoriasis, skin cancer, acne vulgaris, hair loss, psoriasis and skin aging.

Short Onset and Enhanced Analgesia Following Nasal Administration of Non-Controlled Drugs in Nanovesicular Systems.

Nasal nanovesicular delivery systems (NVS) containing the noncontrolled analgesic drugs Ketoprofen, Butorphanol or Tramadol, incorporated in a phospholipid nanovesicular carrier, were designed and investigated. The systems were first characterized for their physicochemical properties. Due to their composition, comprising propylene glycol as a lipid bilayers fluidizer, these systems contain soft vesicles. Pharmacokinetic profiles of Tramadol in plasma and brain and of Ketoprofen in plasma were also assessed. The analgesic effect of each of the three tested drugs was evaluated in the acetic acid mice model for pain. One important result obtained in this work is that the concentration of Tramadol in rats' plasma and brain increased rapidly after administration, reaching a peak value 10 min after administration with a Cmax of 2 to 5 folds greater than that for the oral or nasal non-vesicular treatments, respectively. In the case of Ketoprofen, the peak of the drug level in plasma was measured 10 min post nasal administration in NVS. The Cmax was three-fold higher relative to oral administration of this drug. In the experiment testing analgesia, a rapid and improved analgesia was observed for the tested drugs when delivered nasally in the nanocarrier. On the other hand, a weaker analgesic effect was observed for oral and nasal control systems. This new approach suggests that nasal delivery of non-controlled drugs in soft nanovesicles may open the way for better and noninvasive treatment of severe pain.

Phospholipid Vesicles for Dermal/Transdermal and Nasal Administration of Active Molecules: The Effect of Surfactants and Alcohols on the Fluidity of Their Lipid Bilayers and Penetration Enhancement Properties.

This is a comprehensive review on the use of phospholipid nanovesicles for dermal/transdermal and nasal drug administration. Phospholipid-based vesicular carriers have been widely investigated for enhanced drug delivery via dermal/transdermal routes. Classic phospholipid vesicles, liposomes, do not penetrate the deep layers of the skin, but remain confined to the upper stratum corneum. The literature describes several approaches with the aim of altering the properties of these vesicles to improve their penetration properties. Transfersomes and ethosomes are the most investigated penetration-enhancing phospholipid nanovesicles, obtained by the incorporation of surfactant edge activators and high concentrations of ethanol, respectively. These two types of vesicles differ in terms of their structure, characteristics, mechanism of action and mode of application on the skin. Edge activators contribute to the deformability and elasticity of transfersomes, enabling them to penetrate through pores much smaller than their own size. The ethanol high concentration in ethosomes generates a soft vesicle by fluidizing the phospholipid bilayers, allowing the vesicle to penetrate deeper into the skin. Glycerosomes and transethosomes, phospholipid vesicles containing glycerol or a mixture of ethanol and edge activators, respectively, are also covered. This review discusses the effects of edge activators, ethanol and glycerol on the phospholipid vesicle, emphasizing the differences between a soft and an elastic nanovesicle, and presents their different preparation methods. To date, these differences have not been comparatively discussed. The review presents a large number of active molecules incorporated in these carriers and investigated in vitro, in vivo or in clinical human tests.

A new nanovesicular system for nasal drug administration.

The goal of this work was to study the characteristics of a new phospholipid nanovesicular carrier for nasal administration of drugs. Multilamellar vesicles were visualized by electron microscopy, and their mean distribution size of 200 nm was evaluated by DLS. Measured pH and viscosity values were found adequate for a nasal delivery carrier. CLS micrographs of the nasal mucosa of rats following administration of the carrier incorporating probes with various properties show delivery into the nasal mucosa layers. Tramadol containing systems were characterized and tested for their analgesic effect in two pain animal models. In mice, a significantly higher antinociceptive effect and a rapid onset of action were obtained as compared to other nasal delivery carriers and to oral treatment. This enhanced analgesic effect was further confirmed in rat pain model and sustained by drug plasma and brain levels. To test the systems behavior in a larger animal, a pharmacokinetic crossover study was carried out in sheep after administrating Tramadol nasally in the nanocarrier and IV. The plasma and CSF absolute bioavailability values were 1.09 and 0.87, respectively. HPLC and LC-MS/MS methods for quantification of Tramadol in plasma, brain and CSF were developed and are presented here. It is noteworthy that no pathological alterations or inflammation signs were observed in rat nasal mucosa following sub-chronic treatment. The results obtained in this work encourage further investigation of using the new carrier for nasal delivery of drugs in humans.

Ethosomes for Dermal Administration of Natural Active Molecules.

Ethosomes are nanovesicular carriers for dermal administration. Phospholipids, ethanol at relatively high concentrations (up to 50%) and water are their main components. Ethosomes are what we call "soft vesicles" with fluid bilayers due to the presence of ethanol. The composition and structure of the vesicles augment their ability to entrap molecules with various physicochemical properties and deliver them to the deep strata of skin. Since their first design, ethosomal systems have been extensively investigated for a wide range of applications. This review focuses on work carried out in vitro, in vivo in animal models and in humans in clinical studies, with ethosomal formulations containing natural active molecules for the treatment of skin disorders. Skin bacterial and fungal infections, skin inflammation, acne vulgaris, arthritis, and skin cancer are examples of disorders managed successfully by ethosomal systems. Furthermore, Ethosomes loaded with a number of naturally occurring compounds for cosmetic applications are also reported. The efficient treatments together with a good safety profile and lack of toxicity or irritation paved the way towards the development of new dermal therapies.

Buspirone Nanovesicular Nasal System for Non-Hormonal Hot Flushes Treatment.

The aim of this work was to design and characterize a new nanovesicular nasal delivery system (NDS) containing buspirone, and investigate its efficiency in an animal model for the treatment of hot flushes. The presence of multilamellar vesicles with a mean size distribution of 370 nm was evidenced by transition electron microscopy (TEM), cryo-scanning electron microscopy (Cryo-SEM), and dynamic light scattering (DLS) tests. Pharmacodynamic evaluation of the nasal treatment efficacy with the new system was carried out in ovariectomized (OVX) rat—an animal model for hot flushes—and compared with other treatments. We found that the nasal administration of a buspirone NDS resulted in a significant reduction in tail skin temperature (TST). This effect was not observed in the control buspirone-treated groups. Buspirone levels in the plasma and brain of nasally-treated normal rats were quantified and compared with those of rats that had received oral administration by a LC-MS/MS assay. A significantly higher bioavailability was achieved with the new treatment relative to an oral administration of the same drug dose. No pathological changes in the nasal cavity were observed following sub-chronic nasal administration of buspirone NDS. In conclusion, the data of our investigation show that buspirone in the new nanovesicular nasal carrier could be considered for further studies for the development of a treatment for the hot flushes ailment.

Phospholipid Magnesome-a nasal vesicular carrier for delivery of drugs to brain.

The goal of this work was to investigate a new nasal carrier for enhanced drug delivery to brain, we call Phospholipid Magnesome. The system contains soft phospholipid vesicles, composed of phospholipid, water, propylene glycol, magnesium salt, and the mucoadhesive polymer, alginate. The carrier was characterized by various methods: electron microscopy, calorimetry, and dynamic light scattering. The ability of the carrier's vesicles to entrap various molecules was studied by CLSM and ultracentrifugation combined with HPLC quantification. Mucoadhesivity of the carrier was tested in vitro using porcine nasal mucosa. The delivery of rohdamine 6G, insulin, and epidermal growth factor was estimated by two methods, multiphoton microscopy and near infrared (NIR) imaging. Pharmacodynamic effects of nasal treatment with oxytocin and insulin incorporated in Phospholipid Magnesome were evaluated in animal models. Results show that the system is composed of soft multilamellar nanosized vesicles with the ability to entrap both lipophilic and hydrophilic molecules. The mucoadhesivity test results indicate a prolonged contact time of the drug with the nasal membrane as compared to control. Multiphoton microscopy and NIR imaging of brain show effective delivery of the tested molecules to brain following nasal administration in Phospholipid Magnesome relative to controls. Moreover, the results of the pharmacodynamic study measuring the antinociceptive effect of oxytocin administrated nasally to an animal model indicate the efficiency of the Phospholipid Magnesome as compared to three control systems. Further, nasal administration of insulin resulted in a strong and prolonged hypoglycemic effect for the drug incorporated in the new carrier but not for control systems. Based on the results of the histopathological test, the carrier is safe for local administration on the nasal membrane. In conclusion, the results of this study suggest that Phospholipid Magnesome nasal carrier is able to improve drug effects, probably by a combined mechanism, absorption enhancement, and prolongation of mucosal contact.

Scrolls: novel microparticulate systems for enhanced delivery to/across the skin.

We describe the scroll system as a new microparticulate structured delivery system for enhanced delivery to/across the skin. The basic components of the scroll system are non-ionic surface active of the type of alkyl polyglycol ethers and a glycol. The unique structures are preserved with addition of various ingredients such as polymers, vegetable oils, pharmaceuticals, and permeation enhancers but are dismissed when amphiphile is withdrawn. The microparticles have a unique scroll structure with multiple "wrapping." Besides enabling superior permeation of drugs into/across the skin, the drugs delivered by scroll systems were more effective in vitro and in vivo compared to controls. Model drugs presented high entrapment capacity in scroll systems. The systems are stable over time and are safe for skin application. In order to form, they require a small number of ingredients, simple preparation method, and are environment friendly. The scroll systems may be new potential tools in the dermal/transdermal pharmaceutical and cosmetic industry.

Enhanced therapeutic anti-inflammatory effect of betamethasone on topical administration with low-frequency, low-intensity (20 kHz, 100 mW/cm(2)) ultrasound exposure on carrageenan-induced arthritis in a mouse model.

The purpose of this work was to investigate whether low-frequency, low-intensity (20 kHz, <100 mW/cm(2), spatial-peak, temporal-peak intensity) ultrasound, delivered with a lightweight (<100 g), tether-free, fully wearable, battery-powered applicator, is capable of reducing inflammation in a mouse model of rheumatoid arthritis. The therapeutic, acute, anti-inflammatory effect was estimated from the relative swelling induced in mice hindlimb paws. In an independent, indirect approach, the inflammation was bio-imaged by measuring glycolytic activity with near-infrared labeled 2-deoxyglucose. The outcome of the experiments indicated that the combination of ultrasound exposure and topical application of 0.1% (w/w) betamethasone gel resulted in statistically significantly (p < 0.05) enhanced anti-inflammatory activity in comparison with drug or ultrasound treatment alone. The present study underscores the potential benefits of low-frequency, low-intensity ultrasound-assisted drug delivery. However, the proof of concept presented indicates the need for additional experiments to systematically evaluate and optimize the potential of, and the conditions for, tolerable low-frequency, low-intensity ultrasound-promoted non-invasive drug delivery.

Pouch drug delivery systems for dermal and transdermal administration.

In this work, we have designed and investigated a new carrier for dermal and transdermal drug delivery. The delivery system is composed of high (>60 %) ethanol concentration, phospholipid, polymer, and water. The system forms a structured matrix following non-occluded application on the skin. We call these structured carriers as pouch drug delivery systems (PDDS). The pouch-structured matrix was characterized by electron microscopy, (31)P-NMR and FTIR. The new delivery system exhibits a number of properties adequate for the design of improved dermal and transdermal drug administration for various treatments. Lidocaine PDDS dry faster and has an enhanced dermal drug delivery when compared to a clinical-used product. These proprieties are important for the prevention of premature ejaculation. Results obtained in pharmacodynamics test carried out with brotizolam PDDS in a mice-sleeping model and with ibuprofen PDDS in fevered rats indicated a prolonged hypnotic and antipyretic effect, respectively. The carrier was found nonirritant in tests carried out on EpiDerm(TM) skin model.

Nasal administration of drugs as a new non-invasive strategy for efficient treatment of multiple sclerosis.

We investigated the efficiency of nasal drug administration as a new non-invasive treatment strategy for MS. Glatiramer Acetate (GA) and GA-Cannabidiol (CBD) combination administered in nasal delivery system (NDS) resulted in a statistically significant decrease of clinical scores and inflammatory cytokine expression in experimental autoimmune encephalomyelitis (EAE) mice. Even a suboptimal dose of Prednisolone in NDS was effective in preventing the clinical signs of the disease. Neuron regeneration was observed in the hippocampus of EAE mice treated with GA-CBD in NDS. This work shows that nasal administration improved drug efficiency and stimulates further research for a non-invasive strategy for MS.

A new approach for skin tumor treatment: from delivery system characterization to in vivo evaluation.

Topical therapy for skin cancer is considered ineffective, due to insufficient penetration of the anticancer drug into the tumor located in the deep layers of the skin. The aim of this work was to investigate a new system, Tumorep DS, tailored to deliver the anti-cancer actives into the tumor cells in the deep skin and to induce cell differentiation. Tumorep DS containing 5-fluorouracil (5-FU) anticancer drug and a sulfoxide derivative, as a differentiation agent, was characterized and tested for storage stability. The system was tested in cell lines, in vitro and in animal models. Experiments were carried out on five cell types: three tumorigenic (TE.354.T, ES-2, and Mel624), one precancerous (HaCaT), and a primary keratinocyte (human normal keratinocytes) cell culture. Treatment of keratinocytes with Tumorep DS resulted in reduction in the percent of keratin 14-positive cells, suggesting its ability to induce cell differentiation. Skin penetration was assessed in vitro in Franz diffusion cells and in vivo. The antitumor effect of the new system evaluated in two skin cancer animal models showed a significant repression of tumor development, which was significantly better statistically than a 5-FU commercial product. Tumorep DS was found to be safe to the skin when tested in vitro in the EpiDerm™ skin irritation test and in animals.

Ibuprofen transdermal ethosomal gel: characterization and efficiency in animal models.

A new ibuprofen transdermal nanosystem, designed by using an ethosomal carrier, was characterized and tested for its pharmacokinetic profile and therapeutic effects in animal models. It was found that the ethosomal nanosystem contains unilamellar vesicles with a normal size distribution of about 200 nm. The drug applied transdermally from the ethosomal gel was present in plasma for a longer period of time as compared to the oral administration and showed a high relative bioavailability. Ibuprofen plasma concentration reached a Cmax of 74.11 +/- 18.52 microg/ml 2 hours post application on rat skin. The ibuprofen ethosomal gel had an efficient antipyretic effect in fevered rats. Animal body temperature decreased to normal value gradually with duration of action of at least 12 hours compared to only 7 hours after the oral treatment. The transdermal ibuprofen gel also induced an analgesic effect 30 minutes following its application lasting for at least 6 hours. Biochemical and clinical hematological analysis results of the blood taken from animals in all experimental groups and those of skin histological examination show that ibuprofen ethosomal gel is safe and does not irritate the skin. Data obtained in this work suggest that the designed ethosomal ibuprofen gel could be further investigated in humans for its antipyretic effect.