Cancer is the second cause of human mortality after cardiovascular disease around the globe. Conventional cancer therapies are chemotherapy, radiation, and surgery. In fact, due to the lack of absolute specificity and high drug concentrations, early recognition and treatment of cancer with conventional approaches have become challenging issues in the world. To mitigate against the limitations of conventional cancer chemotherapy, nanomaterials have been developed. Nanomaterials exhibit particular properties that can overcome the drawbacks of conventional therapies such as lack of specificity, high drug concentrations, and adverse drug reactions. Among nanocarriers, mesoporous silica nanoparticles (MSNs) have gained increasing attention due to their well-defined pore size and structure, high surface area, good biocompatibility and biodegradability, ease of surface modification, and stable aqueous dispersions. This review highlights the current progress with the use of MSNs for the delivery of chemotherapeutic agents for the diagnosis and treatment of cancer. Various stimuli-responsive gatekeepers, which endow the MSNs with on-demand drug delivery, surface modification strategies for targeting purposes, and multifunctional MSNs utilized in drug delivery systems (DDSs) are also addressed. Also, the capability of MSNs as flexible imaging platforms is considered. In addition, physicochemical attributes of MSNs and their effects on cancer therapy with a particular focus on recent studies is emphasized. Moreover, major challenges to the use of MSNs for cancer therapy, biosafety and cytotoxicity aspects of MSNs are discussed.

Graphical Application of nanostructures in ocular delivery of natural products.

Quercetin, a substance from nature has various biological effects; while, some challenges like low solubility in water and absorption, and high first-pass metabolism hindered its clinical efficiencies. So, various strategies using novel nanocarriers have been designed to overcome these obstacles. This study aimed to fabricate the polymeric niosomes by incorporating hyaluronic acid to deliver quercetin. After preparation, quercetin entrapped niosomes were investigated in terms of size, zeta potential, quercetin entrapment, CTAB turbidimetric assay, AFM, TEM, differential scanning Calorimetry, X-Ray diffraction, DPPH antioxidant determination, and in vivo anti-inflammatory analysis. The analysis of the results exhibited that size of niosomes containing quercetin and hyaluronic acid was 231.07 ± 8.39 nm with a zeta potential of −34.00 ± 0.95 mV. Moreover, quercetin entrapment efficiency and loading were 94.67 ± 1.62% and 1.65 ± 0.37%, respectively. TEM and AFM showed that polymeric niosomes were spheres. The release data presented that the Higuchi model was the best-fitted model. DPPH antioxidant determination displayed that 80 µl of polymeric niosomes with 7.46 × 10⁻⁸mol of quercetin had a remarkable antioxidant potency. According to the in vivo oedema evaluation, the potency of polymeric formulations was superior to the simple suspension of quercetin to control inflammation in rats by oral administration.