FericipXT-coated PEGylated rutile TiO2 nanoparticles in drug delivery: in vitro assessment of imatinib release.

This study presents a facile synthesis strategy for magnetic field-responsive PEGylated iron-supplement-coated rutile titanium dioxide (TiO2) nanoparticles (NPs) for stimulus-responsive drug delivery. Imatinib, an anticancer drug, was successfully loaded into NPs, and its in vitro release was investigated under different pH conditions. XRD analysis confirmed the successful synthesis of PEGylated iron supplement-coated rutile titania NPs. HR-TEM studies revealed an increased NP size due to the coating, PEGylation, and drug loading, which was corroborated by FTIR spectra, confirming the drug loading into the NPs. DLS provided a hydrodynamic diameter of 642.2 nm and polydispersity index of 0.277 for PEGylated NPs, indicating their enhanced biodistribution and narrow size distribution. PEGylated NPs exhibited a negative zeta potential of -32.89 mV, indicating high stability. In vitro drug-release studies demonstrated controlled release with maximum efficiency under acidic conditions. Hemolysis assay confirmed the safety and biocompatibility of PEGylated NPs. All drug-loaded nanoformulations followed the Peppas-Sahlin model, suggesting Fickian diffusion and Case II relaxation mechanism of drug release. These NPs have the potential for the targeted delivery and controlled release of chemotherapeutics, thereby minimizing side effects.

Local administration of myeloid-derived suppressor cells prevents progression of immune-mediated dry eye disease.

Myeloid derived suppressor cells (MDSCs) are a heterogenous population of immature hematopoietic precursors with known immunoregulatory functions. The immunosuppressive role of MDSCs has been highlighted in several inflammatory ophthalmic disorders; however, their therapeutic application in suppressing the immune-mediated changes in dry eye disease (DED) has not been studied. We observed significant reduction in antigen presenting cell (APC) frequencies and their maturation in the presence of MDSCs. Moreover, co-culturing MDSCs with T helper 17 cells (Th17) resulted in reduced Th17 frequencies and their IL-17 expression. On the contrary, MDSCs maintained regulatory T cell frequencies and enhanced their function in-vitro. Furthermore, we delineated the role of interleukin-10 (IL-10) secreted by MDSCs in their immunoregulatory functions. We confirmed these results by flow cytometry analysis and observed that treatment with MDSCs in DED mice effectively suppressed the maturation of APCs, pathogenic Th17 response, and maintained Treg function and significantly ameliorated the disease. The results in this study highlight the potential therapeutic application of MDSCs in treating refractory DED.

In-vitro pH-responsive release of imatinib from iron-supplement coated anatase TiO2 nanoparticles.

Targeted drug delivery is one such precision method of delivering medication inside the human body which can vanquish all the limitations of the conventional chemotherapeutic techniques. In the present study, two types of nanoparticles (NPs) were chosen for the in-vitro pH-responsive release study of the drug, Imatinib, namely anatase Titanium Dioxide nanoparticles (TiO2 NPs) and iron-capped TiO2 NPs, designated as Fe@TiO2 NPs. The novelty of this work lies behind the use of commercially available iron supplement 'Autrin' meant for human consumption, as the material to coat the TiO2 NPs to synthesize Fe@TiO2 NPs. The synthesized NPs were analyzed by XRD, HR-TEM, SAED, EDX and VSM. UV-Vis spectroscopy was performed for absorption studies. Fe@TiO2 NPs showed superparamagnetic behavior and thus they are able to ensure the facile transfer of Imatinib via external magnetic fields. The results obtained from in-vitro drug release studies depicted that both TiO2 NPs and Fe@TiO2 NPs showed a controlled pH-sensitive delivery of the loaded Imatinib molecules. Moreover, both types of NPs do not result in the formation of ROS under human physiological conditions. These results can lay the foundation to the development of efficacious targeted drug delivery systems in the healthcare sector.