Administration of substances through the skin represents a promising alternative, in relation to other drug administration routes, due to its large body surface area, in order to offer ideal and multiple sites for drug administration. In addition, the administration of drugs through the skin avoids the first-pass metabolism, allowing an increase in the bioavailability of drugs, as well as reducing their side effects. However, the stratum corneum (SC) comprises the main barrier of protection against external agents, mainly due to its structure, composition and physicochemical properties, becoming the main limitation for the administration of substances through the skin. In view of the above, pharmaceutical technology has allowed the development of multiple drug delivery systems (DDS), which include liquid crystals (LC), cubosomes, liposomes, polymeric nanoparticles (PNP), nanoemulsions (NE), as well as cyclodextrins (CD) and dendrimers (DND). It appears that the DDS circumvents the problems of drug absorption through the SC layer of the skin, ensuring the release of the drug, as well as optimizing the therapeutic effect locally. This review aims to highlight the DDS that include LC, cubosomes, lipid systems, PNP, as well as CD and DND, to optimize topical skin therapies.

Ursolic acid (UA) is a naturally occurring triterpenoid which is a promising candidate for the development of new therapeutic approaches and for the prevention and treatment of several diseases owing to its pharmacological importance. However, its low solubility in aqueous medium affects its therapeutic application. Several strategies have been used to overcome this obstacle. In this study, the incorporation of UA in to different drug delivery systems was found to be highly efficient. In addition, important investigations were performed about methods for qualitative and quantitative analyses of UA in various raw materials, including plants, biological fluids, and drug delivery systems, were investigated. Most recently high performance liquid chromatography coupled with various detectors, gas chromatography-mass spectrometry and capillary electrophoresis were used for this purpose. Thus, this review was performed to evaluate the biological effects of UA demonstrated thus far as well as the currently used, delivery systems and analytical methods.

Photodynamic therapy (PDT) is a noninvasive therapeutic approach that has been applied in studies for the treatment of various diseases. In this context, PDT has been suggested as a new therapy or adjuvant therapy to traditional cancer therapy. The mode of action of PDT consists of the generation of singlet oxygen (¹O₂) and reactive oxygen species (ROS) through the administration of a compound called photosensitizer (PS), a light source, and molecular oxygen (³O₂). This combination generates controlled photochemical reactions (photodynamic mechanisms) that produce ROS, such as singlet oxygen (¹O₂), which can induce apoptosis and/or cell death induced by necrosis, degeneration of the tumor vasculature, stimulation of the antitumor immune response, and induction of inflammatory reactions in the illuminated region. However, the traditional compounds used in PDT limit its application. In this context, compounds of biotechnological origin with photosensitizing activity in association with nanotechnology are being used in PDT, aiming at its application in several types of cancer but with less toxicity toward neighboring tissues and better absorption of light for more aggressive types of cancer. In this review, we present studies involving innovatively developed PS that aimed to improve the efficiency of PDT in cancer treatment. Specifically, we focused on the clinical translation and application of PS of natural origin on cancer.

Docetaxel (DTX) is an antineoplastic agent of the second generation of the taxoid family. It is a semi-synthetic drug prepared from a precursor extracted of the plant Taxus baccata. The commercial formulation of DTX, Taxotere®, employs the surfactant polysorbate 80, due to the low water solubility of the drug, causing several side effects. Therefore, there is a need to develop delivery systems to reduce the side effects of DTX. In addition, this drug has been qualitative and quantitatively analyzed in pharmaceutical formulations and biological samples. Thus, several techniques and analytical methods have been reported with the aim of optimizing the analytical signal, increasing sensitivity, selectivity and reducing the effects of interference. Herein, we highlight immunoassay, capillary electrophoresis and chromatographic methods. This review presents a summary of physicochemical and pharmacokinetics properties, mechanisms of action, drug delivery systems and analytical methods used in quantification of DTX in diverse matrices such as blood, plasma, oral fluid, urine, carcinoma cells, pharmaceutical formulations and delivery systems.

Transferrin is a protein involved in iron uptake by cells and has been identified as a potential target for directing drug-loaded nanoparticles for cancer treatment and diagnosis. Most methods for conjugation of transferrin and nanoparticles involve the formation of a thioeter bond between thiolated transferrin and maleimide-containing nanoparticle. For nanoparticle development, it is important to perform a thorough physicochemical characterization, including quantification of the amount of transferrin functionalizing the delivery system. Thus, following the transferrin and nanoparticle chemical conjugation, an analytical method is need for transferrin quantification. Altogether, we revised both physicochemical and pharmacokinetics transferrin characteristics, the aspects of iron transport after interaction with transferrin, the development of transferrin targeted-nanoparticles, highlighting both their composition, synthesis methods and in vitro/in vivo evaluation. Furthermore, we addressed the analytical methods employed in protein quantification, including spectrophotometric/colorimetric, immunoassays, electrophoretic and chromatographic techniques used to identify and/or quantify of transferrin in biological matrices and drug delivery systems.