*Lipid and Polymeric Nanocapsules DOI: http://dx.doi.org/10.5772/intechopen.103906*

Health properties are attributed to the low water-soluble components of garlic oil diallyl disulfide (DADS) and diallyl trisulphide (DATS). Among these is anticancer activity. Both compounds were encapsulated in oil-core nanocapsules of hyaluronic acid. It was proved that encapsulation inhibits the membrane lysis of red blood cells (chiefly provoked by DADS), that the shell acts as a limiting barrier for the sulfur oxidation of the compounds, and that they preserve their biological and anticancer properties after encapsulation. Oleic acid was carried in this same type of nanocapsules and it was concluded that in presence of amphiphilic derivates of hyaluronic acid as a shell of the nanocapsules it is not necessary to include low molecular weight (co)surfactants [80].

Chitosan-coated PCL nanocapsules loaded with simvastatin resulted to be a promising strategy for simvastatin administration within a nose-to-brain approach for brain tumors therapy. Lipid-core nanocapsules coated with chitosan of different molecular weights were prepared by a novel one-pot technique. All formulations presented adequate particle sizes, positive surface charge, narrow droplet size distribution, and high encapsulation efficiency. The nanocapsules allowed for controlled drug release and displayed mucoadhesive properties dependent on the molecular weight of the coating chitosan [81]. Polymeric nanocapsules of Eudragit® were successfully prepared to load thymoquinone. They were conjugated with anisamide as ligand for sigma receptors overexpressed by colon cancer cells [82]. In a bibliographical review, the use of nanocapsules is summarized, among other nanocarriers, for immunotherapy against cancer. As an example, gemcitabine encapsulated in PEGylated lipid nanocapsules is reported. These nanostructures enter macrophages and tumoral cells [107]. Also, lipid nanocapsules (100 nm) loaded with lauroyl-modified gemcitabine efficiently target monocytic myeloid-derived suppressor cells in melanoma patients. The size and charge of nanocapsules can be modulated to reach immunosuppressive cells [83]. The antitumoral effect and the safety of nanocapsules made from a multifunctional component based on Lecigel® phospholipids loaded with the anticancer drug phloretin were tested. This drug is little soluble in an aqueous medium, and therefore, its dermatologic formulations are limited. With the prepared hydrogel, capacity to get through the skin layers was proved, as well as the drug reservoir role in the corneum stratum. Hence, it is presented as an innovative formulation to be applied in melanoma therapy [84]. Itraconazole is an antifungal drug to which are attributed potential anti-cancerous effects with few side effects. Lipid nanocapsules were proposed for the combined therapy with miltefosine and itraconazole, and an increase in the chemotherapeutic efficacy was observed. These nanocapsules were prepared from Labrafil® (oleoyl polyoxyl-6 glycerides), Labrafac® (caprylic-capric acid triglycerides), Transcutol® (diethylene glycol monoethyl ether), and Lipoid® (soybean lecithin, phosphatidylcholine, and phosphatidyl ethanolamine). Lipid systems were also prepared to study their efficacy as topic formulations with fungal and non-fungal effects [85, 86].

In Ref. [87], the possibility to supply intravenously lipid nanocapsules of 50 nm approx. was investigated, and it was checked whether this is viable for the treatment of different cancer types. Six different kinds of drugs were employed; encapsulation efficacy was good and *in vivo* experiments showed that the combination of SN38 and regorafenib in lipid nanocapsules is useful for the treatment of colorectal cancer. Also, sorafenib, a tyrosine kinase inhibitor, was encapsulated in lipid nanocapsules against glioblastoma and the results suggest that they can be used to improve chemotherapy and radiotherapy efficacy [88]. There also exist studies on imatinib, another tyrosine

kinase inhibitor, delivered in lipid nanocapsules against melanoma [89]. The therapeutic efficacy against osteosarcoma was increased by ifosfamide-loaded-lipid-core nanocapsules, with significantly higher cytotoxicity of the drug than free ifosfamide at the same concentration. The apoptosis of cancer cells was increased by the prepared system by increasing the expression levels of caspase-3 and caspase-9 in MG63 cells [90]. A hydrophilic antimitotic agent for breast cancer, vinorelbine bitartrate, was incorporated in the lipid aqueous core of nanocapsules protected with a lipid shell. The release mechanism resulted to be Fickian diffusion, and hemocompatibility studies were also carried out to ensure safety in the case of intravenous administration [91].
