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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.