Improving Dermal Delivery of Rose Bengal by Deformable Lipid Nanovesicles for Topical Treatment of Melanoma.

Cutaneous melanoma is one of the most aggressive and metastatic forms of skin cancer. However, current therapeutic options present several limitations, and the annual death rate due to melanoma increases every year. Dermal delivery of nanomedicines can effectively eradicate primary melanoma lesions, avoid the metastatic process, and improve survival. Rose Bengal (RB) is a sono-photosensitizer drug with intrinsic cytotoxicity toward melanoma without external stimuli but the biopharmaceutical profile limits its clinical use. Here, we propose deformable lipid nanovesicles, also known as transfersomes (TF), for the targeted dermal delivery of RB to melanoma lesions to eradicate them in the absence of external stimuli. Considering RB's poor ability to cross the stratum corneum and its photosensitizer nature, transfersomal carriers were selected simultaneously to enhance RB penetration to the deepest skin layers and protect RB from undesired photodegradation. RB-loaded TF dispersion (RB-TF), prepared by a modified reverse-phase evaporation method, were nanosized with a ζ-potential value below -30 mV. The spectrophotometric and fluorimetric analysis revealed that RB efficiently interacted with the lipid phase. The morphological investigations (transmission electron microscopy and small-angle X-ray scattering) proved that RB intercalated within the phospholipid bilayer of TF originating unilamellar and deformable vesicles, in contrast to the rigid multilamellar unloaded ones. Such outcomes agree with the results of the in vitro permeation study, where the lack of a burst RB permeation peak for RB-TF, observed instead for the free drug, suggests that a significant amount of RB interacted with lipid nanovesicles. Also, RB-TF proved to protect RB from undesired photodegradation over 24 h of direct light exposure. The ex vivo epidermis permeation study proved that RB-TF significantly increased RB's amount permeating the epidermis compared to the free drug (78.31 vs 38.31%). Finally, the antiproliferative assays on melanoma cells suggested that RB-TF effectively reduced cell growth compared to free RB at the concentrations tested (25 and 50 µM). RB-TF could potentially increase selectivity toward cancer cells. Considering the outcomes of the characterization and cytotoxicity studies performed on RB-TF, we conclude that RB-TF represents a valid potential alternative tool to fight against primary melanoma lesions via dermal delivery in the absence of light.

Rapamycin-based inhaled therapy for potential treatment of COPD-related inflammation: production and characterization of aerosolizable nano into micro (NiM) particles.

Our paper describes the production and characterization of inhalable microparticles loaded with nanoparticles for the lung administration of rapamycin (Rapa). In detail, core-shell lipid/polymer hybrid nanoparticles loaded with Rapa (Rapa@Man-LPHNPs) were produced with mean size of about 128 nm and slightly negative ζ potential (-13.8 mV). A fluorescent graft polyaspartamide-poly(lactic-co-glycolic acid) copolymer (PHEA-g-RhB-g-PLGA) for use as the polymeric core was obtained by nanoprecipitation, while an appropriate mixture of DPPC and mannosylated phospholipid (DSPE-PEG2000-Man) was used to provide the macrophage-targeting lipid shell. The successful formation of Rapa@Man-LPHNPs was confirmed by TEM and DSC analyses. The loaded drug (4.3 wt% of the total weight) was slowly released from the polymeric core and protected from hydrolysis, with the amount of intact drug after 24 h of incubation in the medium being equal to 74 wt% (compared to 40% when the drug is freely incubated at the same concentration). To obtain a formulation administrable by inhalation, Rapa@Man-LPHNPs were entrapped inside PVA : LEU microparticles by using the nano into micro (NiM) strategy, specifically by spray drying (SD) in the presence of a pore-forming agent. In this way, NiM particles with geometric and theoretical aerodynamic diameters equal to 4.52 µm and 3.26 µm, respectively, were obtained. Furthermore, these particles showed optimal nebulization performance, having an FPF and an MMAD equal to 27.5% and 4.3 µm, respectively.

Polyphosphoester-stabilized cubosomes encapsulating a Ru(II) complex for the photodynamic treatment of lung adenocarcinoma.

The clinical translation of photosensitizers based on ruthenium(II) polypyridyl complexes (RPCs) in photodynamic therapy of cancer faces several challenges. To address these limitations, we conducted an investigation to assess the potential of a cubosome formulation stabilized in water against coalescence utilizing a polyphosphoester analog of Pluronic F127 as a stabilizer and loaded with newly synthesized RPC-based photosensitizer [Ru(dppn)2(bpy-morph)](PF6)2 (bpy-morph = 2,2'-bipyridine-4,4'-diylbis(morpholinomethanone)), PS-Ru. The photophysical characterization of PS-Ru revealed its robust capacity to induce the formation of singlet oxygen (1O2). Furthermore, the physicochemical analysis of the PS-Ru-loaded cubosomes dispersion demonstrated that the encapsulation of the photosensitizer within the nanoparticles did not disrupt the three-dimensional arrangement of the lipid bilayer. The biological tests showed that PS-Ru-loaded cubosomes exhibited significant phototoxic activity when exposed to the light source, in stark contrast to empty cubosomes and to the same formulation without irradiation. This promising outcome suggests the potential of the formulation in overcoming the drawbacks associated with the clinical use of RPCs in photodynamic therapy for anticancer treatments.

Development of Nanofibers with Embedded Liposomes Containing an Immunomodulatory Drug Using Green Electrospinning.

Conventional treatments for chronic wounds are often ineffective, thus new therapeutic approaches are needed, such as the delivery of immunomodulatory drugs that can reduce inflammation, restore immune cell function, and facilitate tissue regeneration. A potential drug for such an approach is simvastatin, which has major drawbacks including poor solubility and chemical instability. With the aim of developing a dressing for wound healing, simvastatin and an antioxidant were incorporated into alginate/poly(ethylene oxide) nanofibers by green electrospinning without the use of organic solvents, thanks to their prior encapsulation into liposomes. The composite liposome-nanofiber formulations exhibited fibrillar morphology (160-312 nm) and unprecedentedly high phospholipid and drug content (76%). Transmission electron microscopy revealed dried liposomes as bright ellipsoidal spots homogeneously distributed over the nanofibers. After nanofiber hydration, the liposomes reconstituted in two size populations (~140 and ~435 nm), as revealed by cutting-edge MADLS® analysis. Lastly, in vitro assays demonstrated that composite liposome-nanofiber formulations are superior to liposomal formulations due to a better safety profile in keratinocytes and peripheral blood mononuclear cells. Furthermore, both formulations exhibited similarly advantageous immunomodulatory effects, measured as decreased inflammation in vitro. A synergistic combination of the two nanodelivery systems shows promise for the development of efficient dressings for chronic wound treatment.

Bentonite- and Palygorskite-Based Gels for Topical Drug Delivery Applications.

Bentonite or palygorskite-based hydrogels have recently been suggested as a strategy to increase bioavailability and control the retention and release of therapeutic candidates. In this work, clay-based hydrogels loaded with diclofenac acid nanocrystals have been successfully designed and developed. The aim was to improve diclofenac solubility, its dissolution rate and to enhance its local bioavailability after topical application. For this purpose, diclofenac acid nanocrystals were prepared by wet media milling technology and then loaded into inorganic hydrogels based on bentonite and/or palygorskite. Diclofenac acid nanocrystals were characterized by morphology, size, and zeta potential. Moreover, rheological behavior, morphology, solid state, release studies, and in vitro skin penetration/permeation of diclofenac acid nanocrystals-loaded hydrogels were performed. The hydrogels were characterized by a crystalline structure, and demonstrated that the inclusion of diclofenac in clay-based hydrogels resulted in an increased thermal stability. The presence of both palygorskite and bentonite reduced nanocrystal mobility, and consequently its release and penetration into the skin. On the other hand, bentonite- or palygorskite-based hydrogels revealed great potential as an alternative strategy to enhance topical bioavailability of DCF nanocrystals, enhancing their penetration to the deeper skin layers.

Nanosuspension-Based Dissolvable Microneedle Arrays to Enhance Diclofenac Skin Delivery.

Applying a formulation on the skin represents a patient-acceptable and therapeutically effective way to administer drugs locally and systemically. However, the stratum corneum stands as an impermeable barrier that only allows a very limited number of drugs to be distributed in the underlying tissues, limiting the feasibility of this administration route. Microneedle arrays are minimally invasive platforms that allow the delivery of drugs within/across the skin through the temporary mechanical disruption of the stratum corneum. In this work, microneedle arrays were combined with nanosuspensions, a technology for solubility enhancement of water insoluble molecules, for the skin delivery of diclofenac. Nanosuspensions were prepared using a top-down method and loaded in the tips of 500 µm or 800 µm high microneedles. The quality of the combined platform was assessed using electron microscopy and spectroscopic and calorimetry techniques, demonstrating the ability to load high amounts of the hydrophobic drug and the compatibility between excipients. Lastly, the application of nanosuspension-loaded microneedles on the skin in vitro allowed the delivery of diclofenac within and across the stratum corneum, proving the potential of this combination to enhance skin delivery of scarcely soluble drugs.

Inhalable polymeric microparticles as pharmaceutical porous powder for drug administration.

In this work, the production of inhalable polymeric microparticles with modulable porosity is described. The starting polymeric material was the PHEA-g-RhB-g-PLA graft copolymer, which was suitably processed by spray drying (SD). Thanks to the addition of AB (weight percentage equal to 10 and 20 % with respect to the polymer) in the liquid feed, three biocompatible matrices were obtained with an increasing porosity in terms of pore volume (from 0.015 to 0.024 cc/g) and pore average diameter (from 1.942 to 3.060 nm), a decreasing tapped density values (from 0.75 to 0.50), and favorable aerosolization characteristics. These differences were highlighted also by a significant increase in the release of Rapamycin from the sample which showed the higher porosity (31.0 wt% after 24 hrs incubation) than the sample with the lowest porosity (14.9 wt%) in simulated lung fluid.

Clay-Based Hydrogels as Drug Delivery Vehicles of Curcumin Nanocrystals for Topical Application.

The poor water solubility of a significant number of active pharmaceutical ingredients (API) remains one of the main challenges in the drug development process, causing low bioavailability and therapeutic failure of drug candidates. Curcumin is a well-known Biopharmaceutics Classification System (BCS) class IV drug, characterized by lipophilicity and low permeability, which hampers topical bioavailability. Given these premises, the aim of this work was the design and the development of curcumin nanocrystals and their incorporation into natural inorganic hydrogels for topical application. Curcumin nanocrystals were manufactured by the wet ball milling technique and then loaded in clay-based hydrogels. Bentonite and/or palygorskite were selected as the inorganic gelling agents. Curcumin nanocrystal-loaded hydrogels were manufactured by means of a homogenization process and characterized with respect to their chemico-physical properties, in vitro release, antioxidant activity and skin permeation. The results highlighted that the presence of bentonite provided an increase of curcumin skin penetration and simultaneously allowed its radical scavenging properties, due to the desirable rheological characteristics, which should guarantee the necessary contact time of the gel with the skin.

Needle-Free Jet Injectors and Nanosuspensions: Exploring the Potential of an Unexpected Pair.

Needle-free liquid jet injectors are medical devices used to administer pharmaceutical solutions through the skin. Jet injectors generate a high-speed stream of liquid medication that can puncture the skin and deliver the drug to the underlying tissues. In this work, we investigated the feasibility of using liquid jet injectors to administer nanosuspensions, assessing the impact of the jet injection on their pharmaceutical and physicochemical properties. For this purpose, the model drug diclofenac was used to prepare a set of nanosuspensions, stabilized by poloxamer 188, and equilibrated at different pHs. The hydrodynamic diameter and morphology of the nanocrystals were analyzed before and after the jet injection across porcine skin in vitro, together with the solubility and release kinetics of diclofenac in a simulated subcutaneous environment. The efficacy of the jet injection (i.e., the amount of drug delivered across the skin) was evaluated for the nanosuspension and for a solution, which was used as a control. Finally, the nanosuspension was administered to rats by jet injector, and the plasma profile of diclofenac was evaluated and compared to the one obtained by jet injecting a solution with an equal concentration. The nanosuspension features were maintained after the jet injection in vitro, suggesting that no structural changes occur upon high-speed impact with the skin. Accordingly, in vivo studies demonstrated the feasibility of jet injecting a nanosuspension, reaching relevant plasma concentration of the drug. Overall, needle-free jet injectors proved to be a suitable alternative to conventional syringes for the administration of nanosuspensions.

Nanocrystals as an effective strategy to improve Pomalidomide bioavailability in rodent.

Pomalidomide (POM) is an FDA-approved immunomodulatory imide drug (IMiDs) an it is effectively used in the treatment of multiple myeloma. IMiDs are analogs of the drug thalidomide and they have been repurposed for the treatment of several diseases such as psoriatic arthritis and Kaposi Sarcoma. In recent years, IMiDs have been also evaluated as a new treatment for neurological disorders with an inflammatory and neuroinflammatory component. POM draws particular interest for its potent anti-TNF-α activity at significantly lower concentrations than the parent compound thalidomide. However, POM's low water solubility underpins its low gastrointestinal permeability resulting in irregular and poor absorption. The purpose of this work was to prepare a POM nanocrystal-based formulation that could efficiently improve POM's plasma and brain concentration after intraperitoneal injection. POM nanocrystals prepared as a nanosuspension by the media milling method showed a mean diameter of 219 nm and a polydispersity index of 0.21. POM's nanocrystal solubility value (22.97 µg/mL) in phosphate buffer was about 1.58 folds higher than the POM raw powder. Finally, in vivo studies conducted in adult Male Sprague-Dawley rats indicated that POM nanocrystal ensured higher and longer-lasting drug levels in plasma and brain when compared with POM coarse suspension.

The "Prosthetic Orthodontic Approach": An Application of the Biologically Oriented Preparation Technique Protocol.

In this study, three cases involving patients who required multidisciplinary treatment for the aesthetic and functional rehabilitation of the maxillary or mandibular arch are described. In particular, an indication for preprosthetic orthodontic treatment, such as orthodontic extrusion, tooth realignment, correction of malocclusion, and diastemata closure, was present in all cases. Preprosthetic orthodontic treatment to resolve these issues before the restorative procedures was proposed; however, all patients refused preprosthetic orthodontic treatment. Thus, to restore aesthetics and function, solely a feather-edge prosthetic protocol has been used. The biologically oriented preparation technique was used to prepare the teeth that were moved in the established direction by preparing the abutment more on one side than the opposite. This so called "prosthetic orthodontic approach" allowed resolving clinical issues that would typically require preprosthetic orthodontic treatment, such as complete clinical crown loss, occlusal vertical dimension loss, tooth misalignment, malocclusion, tooth agenesis, and severe multiple diastemata. The degree of reciprocal movement of the prepared teeth achievable through this approach was minor and not comparable to a traditional wide-range orthodontic movement. Besides, the technique resulted in a modification of the gingival tissues and improvement of their thickness although it is unclear what effect this technique has on the gingival biotype. None of the patients had prosthetic or periodontal complications for at least 12 months following the procedure. Gingival health was excellent, and the prosthetic procedure did not affect the pulp survival of the vital teeth. The biologically oriented preparation technique used with a prosthetic orthodontic approach can effectively manage complicated cases without the need for preprosthetic orthodontics.

Peri-Implant Tissue Adaptation after Implant Rehabilitation with Shoulderless Abutments with 24 Months of Follow-Up.

An 11-year-old girl presented with agenesis of the maxillary lateral incisors. Orthodontic treatment was performed to close the midline diastema and create adequate space between the central incisors and canines to replace the missing maxillary lateral incisors on both sides. Two-piece implants were placed, and shoulderless abutments were prepared following the "biologically oriented preparation technique" (BOPT) protocol. The soft tissues were allowed to heal directly on the prosthetic emergence profile of the interim crown restorations after implant exposure. Two months later, the gingival tissue adapted to the prosthetic components in a specular manner. No complications were noted at 24 months. The BOPT protocol, originally described for natural teeth, may be applied to dental implants with shoulderless abutments.

Prevalence of peri-implantitis in a sample of HIV-positive patients.

OBJECTIVES: This study aimed to assess the prevalence of peri-implantitis in human immunodeficiency virus (HIV)-positive patients and the presence of a possible correlation between the immunological profile and serological values, of peri-implantitis, and of possible differences between all-on-4 and single crown/bridge prostheses. SUBJECTS AND METHODS: This retrospective study included 58 adult HIV-positive patients (222 implants) with either all-in-4 prostheses or single crowns/bridges on at least one dental implant loaded for more than a year who were followed for 3 year (mean follow-up). Data pertaining to the probing pocket depth (PPD), bleeding on probing, and immunological and systemic profile were collected. RESULTS: Patients with single crown/bridge implant rehabilitation showed higher prevalence of peri-implantitis (34%) than patients with all-on-4 rehabilitation (0%) (p = 0.012). Patients with all-on-4 rehabilitation were significantly older than those with single crowns/bridges (p = 0.004). Patients with peri-implantitis had implants for a significantly longer duration than those without (p = 0.001), implying that the probability of peri-implantitis increases as the age of implant increases. CONCLUSIONS: The prevalence of peri-implantitis was 26% in the HIV-positive patients population. No correlation was found between patients' immunological and serological factors and peri-implantitis. The most important risk factor for peri-implantitis and mucositis was implant age.

Delivery of beclomethasone dipropionate nanosuspensions with an electronic cigarette.

The aim of this work was to ascertain the ability of electronic nicotine delivery systems (ENDS) to deliver drug nanocrystals through the produced aerosol. A nanocrystal nanosuspension of beclomethasone dipropionate, a synthetic chlorinated corticosteroid diester commonly used by inhalation in the treatment of asthma and chronic obstructive pulmonary disease, was prepared with a wet media milling technique using Poloxamer 188 as stabilizer. The obtained nanosuspension was thoroughly characterized by different techniques: transmission electron microscopy, photon correlation spectroscopy, X-ray powder diffractometry and Fourier transform infrared spectroscopy. The nanosuspension was then loaded in the cartomizer of the electronic cigarette and the produced aerosol was collected and analysed, confirming the presence of drug nanocrystals. The results of this study suggested the possible alternative use of ENDS as medical device for the delivery of poorly soluble drugs.

Pulmonary Delivery of Curcumin and Beclomethasone Dipropionate in a Multicomponent Nanosuspension for the Treatment of Bronchial Asthma.

Curcumin has shown a potential extraordinary activity as an add-on ingredient in asthma treatment, due to its immunomodulatory and anti-inflammatory mechanism of action. However, its low water solubility and bioavailability lead to a poor therapeutic effect, which can be overcome by its formulation as nanocrystals. The aim of this study was to prepare a multicomponent formulation for the delivery of curcumin (CUR) and beclomethasone dipropionate (BDP) into the lungs as water-based nanosuspensions (NS). Single component formulations (CUR-NS, BDP-NS) and a multicomponent formulation (CUR+BDP-NS) were prepared through a wet ball media milling technique, using P188 as a non-toxic stabilizer. Characterization was carried out in terms of size, size distribution, zeta potential, nanocrystals morphology, and solid-state properties. Moreover, the inhalation delivery efficiency was studied with Next Generation Impactor (NGI, Apparatus E Ph. Eu). CUR-NS was optimized and showed a long-term stability and improved nanocrystals apparent solubility. The three formulations exhibited a nanocrystal mean diameter in the range of 200-240 nm and a homogenous particle size distribution. Aggregation or sedimentation phenomena were not observed in the multicomponent formulation on 90 days storage at room temperature. Finally, the nebulization tests of the three samples showed optimal aerodynamic parameters and MMAD < 5 µm.

Correction of Gingival Architecture Using the Biologically Oriented Preparation Technique in Two Patients with Human Immunodeficiency Virus.

Two female patients positive for human immunodeficiency virus and receiving antiretroviral treatment presented with esthetic concerns due to fixed dental prostheses in the anterior region. The patients had gingival recession and short clinical crowns in the esthetic zone. In both cases, the biologically oriented preparation technique was used to recreate ideal proportions between the teeth and gingivae. Since patients with human immunodeficiency virus experience a progressive deterioration of their immune systems and other significant comorbidities, a reduction in the number of traumatic clinical procedures is recommended. The use of this minimally invasive prosthetic protocol has not been previously reported in patients with human immunodeficiency virus. These cases demonstrate how short clinical crowns and gingival recession in the esthetic zone can be successfully treated with the biologically oriented preparation technique to avoid surgical procedures in patients with human immunodeficiency virus.

Sustained release of antimicrobials from double-layer nanofiber mats for local treatment of periodontal disease, evaluated using a new micro flow-through apparatus.

Periodontal disease is a widespread chronic condition associated with degradation of periodontal tissues that requires more effective approaches for its treatment. Thus, the aim was to develop a nanodelivery system for local application of antimicrobials, with evaluation in vitro using a newly developed micro flow-through apparatus that simulates local in-vivo conditions in the periodontal pocket: small resting volume, and low gingival crevicular fluid flow rate. We successfully developed a double-layer nanofiber mat composed of a chitosan/ poly(ethylene) oxide nanofiber layer with 30% ciprofloxacin, and a poly(ε-caprolactone) nanofiber layer with 5% metronidazole. The precisely designed composition enabled sustained in-vitro release of the antimicrobials according to their specific drug release mechanisms. The rate-limiting step of ciprofloxacin release was its own low solubility at pH 7.4, when there was excess of solid drug present in the delivery system. In contrast, sustained release of metronidazole was due to slow penetration of dissolution medium through the hydrophobic poly(ε-caprolactone) nanofiber layer. The double-layer nanofiber mat developed showed antibacterial activity against Escherichia coli and Aggregatibacter actinomycetemcomitans based on plate antibiogram assays. The antimicrobial concentrations released from the nanofiber mats determined using the developed apparatus were above the minimal inhibitory concentrations against the periodontal pathogens for up to 7 days, which is valuable information for prediction of the efficacy of the nanodelivery system. Although this apparatus was specifically designed for characterization of formulations associated with treatments for periodontal disease, its applicability is much wide, as for development of any delivery system for application at target sites that have similar local conditions.