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It is a fact that chemotherapy agents have little specificity for cancer cells, this leading to low concentrations into the tumor interstititum and severe side effects on healthy tissues. The formulation of lipid-based nanomedicines against cancer has been hypothesized to improve drug localization into the tumor tissue and to increase the anticancer efficacy of concentional drugs, while minimizing their systemic adverse effects. In this review, special attention is devoted to the analysis of the state-of-the-art in the development of lipid-based drug carriers against cancer. Specifically, the most significant in vitro and in vivo results on the use of niosomes, liposomes, and solid lipid nanoparticles are revised. It is concluded that biodistribution profiles of chemotherapy agents can be controlled by their loading to such nanoplatforms. Lipid-based nanomedicines offer an interesting approach to the delivery of anticancer drugs to brain tumors, and to reverse multi-drug resistance of cancer cells. Finally, a deep evaluation of the applicability of drug delivery strategies in the formulation of lipid-based nanoplatforms is carried out. They involve active drug targeting (including ligand-mediated delivery, and stimuli-sensitive carriers), and passive drug targeting (through the enhanced permeability and retention effect) to tumors.

to moisture diffusion. The lowering of the diffusion coefficient of water vapor by oil films will slow the loss of moisture, an effect similar to 'moisturization' of hair.

Tricyclic antidepressants, as doxepin hydrochloride (DH), may have analgesic local effect due to its biochemical mechanism of action. Delivery of DH directly to the oral cavity could be an interesting alternative for toothache due to its analgesic local effect. One problem associated with the mucosal administration routes is the short residence time of the dosage form on the mucosal membranes. In this sense, we have developed new doxepin mucoadhesive films able of reducing pain and increasing the effectiveness of treatment. For this purpose, we tested three different polymers: chitosan, sodium hydroxypropylmethylcellulose (HPMC) and sodium carboxymethylcellulose (SCMC) in film elaboration. The results obtained show that all films are hydrophilic matrices that absorb water when placed in an aqueous media. All the films hydrated very quickly, reaching high percentage of swelling after just few minutes (5 min for SCMC, 2 min for HPMC and 30 min for chitosan). Moreover, the SCMC and HPMC films were dissolved whereas chitosan was not dissolved. Dissolution also leads to viscous liquids with a higher retention time over mucosal surfaces what may lead to adhesive interactions. In vitro permeation studies showed that for all the formulations studied, SCMC (19.91%), HPMC (69.5%) and chitosan (24.17%), the percentage of drug permeated increased compared to the drug solution (8.26%). Specifically the HPMC film presents greater amounts of doxepin permeated (49.27 ± 4.47 mg/cm 2 ).