Chitosan (Poly-(D) glucosamine) based solid lipid nanoparticles of dexibuprofen for topical delivery: Formulation development and characterizations

Full factorial design, physicochemical characterization, ex vivo investigation, and biological assessment of glutathione-loaded solid lipid nanoparticles for topical application

l-Glutathione (GSH) has exceptional antioxidant activities against UVA irradiation-induced oxidative stress and is used widely for combatting skin ageing. However, topical administration of GSH is challenging due to its inability to penetrate the stratum corneum (SC). This study aims to evaluate the solid lipid nanoparticles (SLNs) carrier system for improving the skin penetration and stability of GSH. The GSH-loaded SLNs (GSH-SLNs) were prepared by the double emulsion technique and were optimized by a full factorial design. The optimized GSH-SLNs formulation had a mean particle size of 305 ± 0.6 nm and a zeta potential of + 20.1 ± 9.5 mV, suitable for topical delivery. The ex-vivo penetration study using human skin demonstrated a 3.7-fold improvement of GSH penetration across SC with GSH-SLNs when compared with aqueous GSH. GSH-SLNs prolonged antioxidant activity on UVA irradiated fibroblast cells when compared to GSH solution, preventing UVA-induced cell death and promoting cell growth for times over 48 h. This research has illustrated that as a carrier system, SLNs were able to enhance the physicochemical stability, skin penetration, and drug deposition in the viable epidermis and dermis layers of the skin for GSH, while also maintaining the ability to protect human skin fibroblast cells against oxidative stress caused by UVA irradiation. This delivery system shows future promise as a topical delivery platform for the topical delivery of GSH and other chemically similar bioactive compounds for improving skin health.

Exploring curcumin interactions with BN nanostructures: A DFT approach

Density functional theory (DFT) calculations were performed to investigate the curcumin adsorption at the surfaces of two boron nitride (BN) nanostructures including nanosheet (BNNS) and nanotube (BNNT). The singular models were optimized to reach the stabilized structures and to evaluate electronic features. Next, performing optimization processes on interacting systems yielded formations of bimolecular complexes through occurrence of physical interactions. For curcumin, keto and enol tautomeric forms were investigated for participating in interactions with the BN nanostructures, in which the enol form was seen for participating in stronger interactions with both of BNNS and BNNT surfaces in comparison with the keto form. Based on such interactions, electronic molecular orbital features detected the effects of molecular communications to show benefit of employing BN nanostructures for drug delivery purposes. Moreover, BNNS was seen to work better than BNNT for such purpose of adsorption and detection of curcumin substance.

Interaction of a conical carbon scaffold with the thio-substituted model of fluorouracil towards approaching the drug delivery purposes

A representative FeN4-doped conical carbon (C) scaffold was investigated for participating in interactions with the thio-substituted fluorouracil (SFU) anticancer drug by performing density functional theory (DFT) calculations. In this regard, all possible relaxation configurations of SFU at the doped tip of C scaffold were examined, in which three models were obtained including one horizontal relaxation configuration (FC1) and two vertical relaxation configurations (FC2 and FC3). The results indicate the highest stability and strength for FC1 model. Examining formations and strengths of interactions showed two medium strength interactions in each of FC1, FC2, and FC3 models. Moreover, the evaluated electronic molecular orbitals features indicated availability of sensor function for the proposed C scaffold towards the interacting SFU substance. As a consequence, the models were determined to work in dual functions of sensor and carrier towards drug delivery purpose of SFU anticancer drug.

Investigating drug delivery of 5-fluorouracil by assistance of an iron-modified graphene scaffold: Computational studies

This computational work was performed to investigate drug delivery of 5-fluorouracil (FU) anti-cancer by assistance of an iron(Fe)-modified graphene (G) scaffold. The models were optimized to reach the minimized energy structures in both of singular and bimolecular models. Two models of FU@G complex were obtained including O2@G and O4@G by relaxation of FU through O2 and O4 atoms towards the Fe-atom region of G surface. The obtained results of energies indicated a higher stability and strength for the O2@G model in comparison with the O4@G model. The quantitative and qualitative features of electronic molecular orbitals indicated the investigated G surface could work as a carrier of FU by reducing the unwanted side effects and also playing the sensor role. As a final remark of this work, the investigated G model could be proposed for employing in the targeted drug delivery of FU in both of carrier and sensor agents.