Nowadays, the freeze-drying of liposome dispersions is still necessary to provide a solid dosage form intended for different routes of administration (i.e., parenteral, oral, nasal and/or pulmonary). However, after decades of studies the optimization of process conditions remains still challenging since the freezing and the dehydration destabilize the vesicle organization with the concomitant drug leakage. Starting from the thermal properties of phospholipids, this work reviews the main formulation and process parameters which can guarantee a product with suitable characteristics and increase the efficiency of the manufacturing process. In particular, an overview of the cryo- and/or lyo-protective mechanisms of several excipients and the possible use of co-solvent mixtures is provided. Attention is also focused on the imaging methods recently proposed to characterize the appearance of freeze-dried products and liposome dispersions upon reconstitution. The combination of such data would allow a better knowledge of the factors causing inter-vials variability in the attempt to improve the quality of the final medicinal product.

Recently, an increasing number of pharmacists had to supply medicinal products based on L. (Cannabaceae), prescribed by physicians to individual patients. Cannabis olive oil preparation is the first choice as a concentrated extract of cannabinoids, even though standardized operative conditions for obtaining it are still not available. In this work, the impact of temperature and extraction time on the concentration of active principles was studied to harmonize the different compounding methods, optimize the extraction process, and reduce the variability among preparations. Moreover, starting from the cannabis inflorescence, the effect of temperature on tetrahydrocannabinolic acid decarboxylation was evaluated. For the analysis, a GC/MS method, as suggested by the Italian Ministry of Health, and a GC/flame ionization detection method were developed, validated, and compared.

This work demonstrates the feasibility of the extemporaneous preparation of maltodextrins orodispersible films (ODF) by hot-melt ram-extrusion 3D printing. This method consists of three simple technological operations which can be also implemented in a pharmacy setting. First, maltodextrins, drug, and other excipients are mixed in a mortar and wetted with the plasticizer (i.e. glycerine). Then, the mixture is fed in the chamber of the ram-extruder and heated. ODF are individually printed on the packaging material foil and sealed without further manipulations. The critical formulation attributes and process variables were investigated to define the processability space. In particular, the optimal conditions to print a mixture of maltodextrins/glycerine in a 80/20 w/w ratio resulted: heating temperature: 85 °C; needle gauge: 18 G; needle-packaging material foil distance: 0.6 mm; maximum print rate: 50 mm/s; filling angle: 120°. The maximum drug loading was about 40%, when paracetamol was used as model drug. The compounded ODF complied with USP and Ph. Eur. specifications for disintegration time (<1 min). The dissolution pattern of paracetamol overlapped with that obtained from ODF with a similar composition prepared by the consolidated solvent casting technique, demonstrating the suitability of the proposed technology.

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Cannabidiol (CBD) is a non-psychoactive cannabinoid isolated from Cannabis sativa which, given its claimed beneficial properties and therapeutic potential, has lately aroused considerable attention from the scientific community. Starting from the little literature evidence, the main purpose of this study was to investigate the topical administration of CBD, with particular focus on the influence of vehicle-related aspects on the skin permeation process. This could provide useful information for the design of suitable drug delivery systems which could be used in developing topical medicines and cosmetics. In vitro human skin permeation studies were conducted using modified Franz diffusion cells to compare the performance of four solutions and two semisolid formulations. The Hildebrand solubility parameter was used to better understand the thermodynamic aspects implied in the partitioning process of the cannabinoid compound into the skin. It was interestingly found that a hydrophilic gel, mostly consisting of propylene glycol (79%, w/w), can be an optimal choice for the topical administration of CBD. Moreover, the feasibility of the preparation of CBD-loaded (trans)dermal patches, made with new printing technology, was also demonstrated.

Interdental papilla are an interesting source of mesenchymal stromal cells (GinPaMSCs), which are easy to isolate and expand in vitro. In our laboratory, GinPaMSCs were isolated, expanded, and characterized by studying their secretome before and after priming with paclitaxel (PTX). The secretome of GinPaMSCs did not affect the growth of cancer cell lines tested in vitro, whereas the secretome of GinPaMSCs primed with paclitaxel (GinPaMSCs/PTX) exerted a significant anticancer effect. GinPaMSCs were able to uptake and then release paclitaxel in amounts pharmacologically effective against cancer cells, as demonstrated in vitro by the direct activity of GinPaMSCs/PTX and their secretome against both human pancreatic carcinoma and squamous carcinoma cells. PTX was associated with extracellular vesicles (EVs) secreted by cells (EVs/PTX), suggesting that PTX is incorporated into exosomes during their biogenesis. The isolation of mesenchymal stromal cells (MSCs) from gingiva is less invasive than that from other tissues (such as bone marrow and fat), and GinPaMSCs provide an optimal substrate for drug-priming to obtain EVs/PTX having anticancer activity. This research may contribute to develop new strategies of cell-mediated drug delivery by EVs that are easy to store without losing function, and could have a superior safety profile in therapy.

In this work we made an attempt to assess the effect of drug-induced changes of flexibility on the penetration of deformable vesicles into the human skin. Eight cationic liposomes with different degrees of flexibility were obtained by entrapping unfractionated heparin, enoxaparin, and nadroparin. The deformability was studied by a novel, facile, and reliable extrusion assay appositely developed and validated by means of quantitative nanoscale mechanical AFM measurements of vesicle elastic modulus (log(YM)). The proposed extrusion assay, determining the forces involved in vesicles deformation, resulted very sensitive to evidence of minimal changes in bilayer rigidity (σ) and vesicle deformation (K). The drug loading caused a reduction of liposome flexibility with respect to the reference plain liposomes and in accordance to the heparin type, drug to cationic lipid (DOTAP) ratio, and drug distribution within the vesicles. Interestingly, the σ and log(YM) values perfectly correlated (R = 0.935), demonstrating the reliability of the deformability data obtained with both approaches. The combination of TEM and LC-MS/MS spectrometry allowed the pattern of the penetration of the entire vesicles into the skin to be followed. In all cases, intact liposomes in the epidermis layers were observed and a relationship between the depth of penetration and the liposome flexibility was found, supporting the hypothesis of the whole vesicle penetration mechanism. Moreover, the results of the extent (R) of vesicle penetration in the human skin samples showed a direct relation to the flexibility values (σ = 0.65 ± 0.10 MPa → R = 3.33 ± 0.02 μg/mg; σ = 0.95 ± 0.04 MPa → R = 1.18 ± 0.26 μg/mg; σ = 1.89 ± 0.30 MPa → R = 0.53 ± 0.33 μg/mg).

Background/Aim: Topical β-blockers have recently been proposed as a valid alternative to oral drugs for treating cutaneous infantile haemangiomas, but clinical results in the literature are inconsistent due to the empirical choice of topical preparations. The current investigation aimed to rationalize the selection of a semi-solid vehicle for a locally applied drug product containing 1% w/w propranolol hydrochloride (PR-Cl). Methods: A hydrophobic ointment of PR-Cl, two lipophilic creams, and a hydrophilic cream were prepared. In vitro release and skin permeation studies through human epidermis and full-thickness skin were performed by Franz diffusion cells. Results: The overall results highlighted that PR-Cl was able to permeate the human epidermis, and its penetration pattern was strongly influenced by the composition of the semi-solid vehicle. PR-Cl release and permeation from lipophilic vehicles were extremely limited and influenced by their composition. Best results were obtained by using the hydrophilic cream. Furthermore, the retention study evidenced that epidermis acted as a reservoir, releasing the PR-Cl accumulated after preparation removal. Conclusion: The 1% w/w PR-Cl cream resulted the most suitable formulation for improving drug permeation through the human epidermis. On the contrary, the negligible permeation profile through full-thickness skin pointed out that PR-Cl cannot diffuse significantly to reach the deeper layers of human skin.