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The aim of this work was the preparation of solid lipid nanoparticles, based on trehalose monooleate, loaded with cyclosporin-A for potential treatment of psoriasis. Trehalose was esterified with oleic acid in order to obtain a more lipophilic compound suitable as a lipid matrix for the formulation of a new type of solid lipid nanoparticles. The ester formation was confirmed by FT-IR and 1HNMR. The solid lipid nanoparticles, based on trehalose monooleate, were successfully prepared with and without cyclosporin-A, using the microemulsion technique. Further characterizations were performed by differential scanning calorimetry (DSC). The drug release from the SLNs was then evaluated through the Franz diffusion cells, using both dialysis membranes and rabbit ear skin. With the aim to verify the localization of SLNs in the skin layers, additional investigations using confocal microscope and stripping tape test were carried out. Finally, a dermatological formulation, based of SLNs loaded with cyclosporin-A, was prepared and tested through Franz diffusion cells. The obtained results indicate the possibility of using these nanoparticles as vehicle of cyclosporin-A for topical treatment of psoriasis, reducing the side effects due to systemic absorption of cyclosporin-A and, at the same time, increasing its concentration at skin injury level.

The aim of this study was the synthesis and characterization of swellable microspheres based on fenoprofen and poloxamer. Morphology, average diameter and thermal behaviour of obtained microparticles were studied by scanning electron microscopy, dynamic light scattering, and differential scanning calorimetry. The swelling degree was evaluated at different time intervals and at two pH values. The results revealed that the microspheres swelled better at a pH 6.2, typical of tumour pathologies, than at 7.4, physiological one. Then, microspheres were impregnated with 5-fluorouracil with the aim to increase its bioavailability and reduce its toxicity. The percentage of cumulative amount of 5-fluorouracil released from microparticles was calculated at pH 6.2. Surprisingly, calorimetry and optical microscopy showed the preservation of fenoprofen liquid crystallinity in the obtained microparticles with a transition temperature close to those of typical tumour-sites. The liquid crystallinity of microparticles could be exploited to modulate the release of 5-fluorouracil to tumour site.

The main target of this study was the preparation, characterization and antioxidant activity evaluation of α-tocopheryl linolenate based solid lipid nanoparticles (SLNs-TL), able to incorporate omega-3 α-linolenic acid, useful for the treatment of melanoma, a type of skin cancer. In particular, α-linolenic acid was successfully derivatized with α-tocopherol and the obtained compound was characterized by Fourier transform infrared (FT-IR) and by 1H NMR to confirm the ester linkage. Both the empty SLNs-TL that SLNs-TL-LIN, containing omega-3-linolenic acid, were prepared through the technique of the microemulsion. The nanoparticles were characterized for entrapment efficiency, size and shape. Their antioxidant activity was investigated in rat liver microsomal membranes in inhibiting the lipid peroxidation induced by tert-butyl hydroperoxide (tert-BOOH), which endogenously produces alkoxyl radicals by Fenton reactions. The obtained results indicate that the α-tocopherol, linked by ester bond to α-linolenic acid, maintains an excellent antioxidant activity. The encapsulation efficiency was equal to 77% and the polydispersity index 0.198 indicating a good dimensional distribution. Furthermore, the nanoparticles were tested in vitro for their cytotoxic activity against human melanoma cancer cell line C32. Both empty SLNs-TL and loaded SLNs-TL-LIN showed a high biological activity, being more effective than α-linolenic acid and α-tocopherol. The results indicated that these nanoparticles could provide the delivery and the protection of unstable molecules, such as α-linolenic acid, from degradation induced by mechanisms of oxidative stress.

Hydrogels have received growing attention as materials for drug delivery systems (DDS) because of their biodegradable and biocompatible properties. DDS were developed to optimize the therapeutic properties of drug products and to render them more safe, effective, and reliable. In the past, drugs were frequently administered orally, as liquids or in powder forms. To avoid problems incurred through the utilization of the oral route of administration, new dosage forms, DDS, containing the drugs were introduced. They can deliver drugs directly to the intended site of action and can also improve treatment efficacy, while minimizing unwanted side effects elsewhere in the body, which often limit the long-term use of many drugs, and provide better efficacy of treatment. Biocompatible hydrogels are an example of such systems available for therapeutic use. In this review, results from recent publications concerning these systems are discussed. Hydrogels show superior effectiveness over conventional methods of treatment providing controlled release of active substances. They are of interest in medical applications such as breast cancer treatment.

Objectives This study concerns the preparation and characterization of microspheres based on a mixture of triterpene saponins, from Physospermum verticillatum (Waldst & Kit), as a carrier for the specific release of gemcitabine. Methods Triterpene saponins were derivatized with acrylic acid. The obtained polymerizable product was characterized by Fourier transform infrared to confirm the ester linkage. Then, spherical microparticles were prepared by suspension radical copolymerization and impregnated with gemcitabine. Key findings Microspheres exhibited a mean diameter of 2.7 μ. The swelling studies showed that particles swell most at pH 6.2, typical of the tumour pathology, than at pH 7.4, miming physiological conditions. The microspheres were loaded with gemcitabine (LE 72.2%). Their release profile showed an initial dot of around 24% and a further release for 24 h. Conclusions This carrier could be potentially release the drug in the lung, as a function of different pHs between tumour cells and healthy, reducing the systemic drug toxicity, allowing the reduction of the doses number, increasing the drug half-life and eliminating the problems related to the fast clearance of gemcitabine administration.

This work concerns on the preparation and performance evaluation of a new chitosan hydroquinone based gauze for hemostatic use. Chitosan and hydroquinone were firstly connected by etherification and then linked to the pre-carboxylate gauze. The functionalized material and the chitosan-hydroquinone ether were characterized by Fourier Transform Infrared (FT-IR) Spectroscopy and Differential Scanning Calorimetry (DSC). FT-IR results showed that an esterification occurred on carboxylic group of the gauze. The gauze functionalization degree was also evaluated by volumetric analysis. The ether hydroquinone content was obtained by the Folin test. Moreover, the linkage between hydroquinone and chitosan was confirmed by nuclear magnetic resonance (NMR). The hemostatic activity of functionalized gauze was evaluated by dynamic blood clotting assays. The obtained results showed that the prepared material can shorten the blood clotting time and induce the adhesion and activation of platelets. Finally, swelling characteristic of the new gauze was evaluated to confirm its high capacity to absorb the blood.

Systemic and local infections caused by fungi, in particular those concerning the skin and nails, are increasing. Various drugs are used for mycoses treatment such as amphotericin B, nystatin and ketoconazole, fluconazole, itraconazole and fluconazole, among others. Unfortunately, many of these antifungal agents can cause side effects such as allergic and severe skin reaction. With the aim to reduce these side effects and maximize the antifungal drug activity, various drug-delivery systems have been formulated and been investigated in the last few years. In this context, solid lipid nanoparticles are attracting great attention. The aim of this review is to highlight the role of solid lipid nanoparticles as carriers of antifungal drugs for topical applications.