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There are various developments in drug delivery systems based on combinations of biomacromolecules and nanoparticles. Since drug delivery is popular in cancer treatment, most of the developments have occurred in oncology. For the treatment of malignant melanoma, folate‐decorated cationic liposomes have been developed as nonviral vectors of hypoxia‐inducible factor 1‐α siRNA (HIF‐1α siRNA). Hypoxia‐inducible factor 1‐α is a transcription factor that responds to hypoxic stress and could be a potential target in malignant melanoma therapy. When HIF‐1α is upregulated, transcription is activated that results in angiogenesis. Small interfering RNA (siRNA) are pieces of double‐stranded RNA that can interfere with the translation of proteins and inhibit angiogenesis when used against HIF‐1α. The double‐stranded RNA alone did not achieve the antiangiogenesis activity, thus HIF‐1α siRNA vector is an excellent vehicle that can load siRNA and protect it from degradation [44]. Another method of delivering anticancer drugs, such as quercetin, is a lecithin‐based mixed polymeric micelle. Although quercetin (Que) is a well‐known and successful anticancer drug, its low solubility and low oral bioavailability (BA) hinders its use in clinical settings. A micelle as a delivery system is quite useful in this case because its hydrophobic core and hydrophilic shell provide a safe passage for low soluble drugs. To increase the solubility of drugs, the more hydrophobic material is added to the micelle, which increases the space in the hydrophobic core and provides more space for drugs to be solubilized. Lecithin is a hydrophobic mixture of organic phospholipids that help in the absorption of drugs. In this case, lecithin helps increase the BA of Que. These micelles not only are able to increase drug solubility and BA but also, due to their nanosize, are able to enter and gather in tumor sites [45].

Even though most of the drug delivery methods are focused on cancer treatments, some specialize in other problematic areas of the human body. Skin is the largest organ of the body and the stratum corneum is the main barrier that drugs need to penetrate to get into the deeper layer of the skin. In the case of antifungals, drugs should be able to get through this layer but are not always able to do so. The development of nanosized colloidal carriers can be used as vehicles for drug delivery. Studies done on naftifine‐loaded microemulsion colloidal carriers showed that the carriers were an effective way of delivering naftifine, an antifungal drug, to deeper layers of the skin. Additionally, the method of delivery was shown to have low levels of cytotoxicity [46].