Insulin smart drug delivery nanoparticles of aminophenylboronic acid–POSS molecule at neutral pH

Self-regulated “smart” insulin administration system that mimic pancreatic endocrine function would be highly desirable for diabetes management. Here, a glucose-responsive continuous insulin delivery system is developed, where novel polyhedral oligosilsesquioxane (POSS) modified with 3‐aminophenylboronic acid (APBA) were used to encapsulate insulin (insulin entrapment efficiency: 73.2%) to prepare a fast response, high stability, good distribution, and excellent biocompatible system. Due to the strong hydrophobicity of POSS, the POSS moiety is located at the core in aqueous solution and combines with the boronic group of APBA and the diol generated in PEG-insulin to form a nanomicelle structure, that is, nanoparticles naturally. Micelles self‐assembled from these molecules possess glucose‐responsiveness at varying glucose concentrations. The interaction of the PBA and diol containing insulin via boronate ester bond and its interchange with glucose was investigated by FT-IR, 1H NMR and XPS. Furthermore, the successful glucose-triggered release of insulin from the POSS-APBA micelles was investigated at neutral pH. A linear graph was plotted with the measured released insulin vs glucose concentrations, with a linear correlation coefficient (R2) value close to 1. Circular dichroism (CD) spectroscopy analysis was performed to measure insulin activity by comparing secondary structures of insulin, PEG-Insulin, and POSS-APBA@insulin. When confirming intracellular apoptosis signaling, cleaved caspase 3 and caspase 9 were not increased by 640 μg/ml POSS-APBA and POSS-APBA@insulin in HeLa, HDF and HUVE cells. Application in the biomedical field for controlled delivery of insulin appear to be promising.

Insulin Smart Drug Delivery Nanoparticles of Aminophenylboronic acid–POSS Molecule at Neutral pH

Self-regulated “smart” insulin administration system that mimic pancreatic endocrine function would be highly desirable for diabetes management. Here, a glucose-responsive continuous insulin delivery system is developed, where novel polyhedral oligosilsesquioxane (POSS) modified with 3-aminophenylboronic acid (APBA) were used to encapsulate insulin (insulin entrapment efficiency : 73.2%; loading capacity : 50.5%) to prepare a fast response, high stability, good distribution, and excellent biocompatible system. Micelles self‐assembled from these molecules possess glucose‐responsiveness at varying glucose concentrations. The interaction of the PBA and diol containing insulin via boronate ester bond and its interchange with glucose was investigated by FT-IR, 1H NMR and XPS. Furthermore, the successful glucose-triggered release of insulin from the POSS-APBA micelles was investigated at neutral pH. A linear graph was plotted with the measured released insulin vs glucose concentrations, with a linear correlation coefficient (R2) value close to 1. When confirming intracellular apoptosis signaling, cleaved caspase 3 and caspase 9 were not increased by 640 µg/ml POSS-APBA and POSS-APBA@Insulin in HeLa cells and HDF cells. Application in the biomedical field for controlled delivery of insulin appear to be promising.

Zirconium and hafnium polyhedral oligosilsesquioxane complexes – green homogeneous catalysts in the formation of bio-derived ethers via a MPV/etherification reaction cascade

Newly designed POSS supported zirconium and hafnium isopropoxides are robust, durable and selective homogeneous catalysts for the conversion of hydroxymethylfurfural to bis(isopropoxymethyl)furane via MPV/etherification reaction with isopropanol as a green solvent/reagent.

Evaluation of elastomeric heat shielding materials as insulators for solid propellant rocket motors: A short review

This review addresses a comparison, based on the literature, among nitrile rubber (NBR), ethylene-propylene-diene-monomer rubber (EPDM), and polyurethane (PU) elastomeric heat shielding materials (EHSM). Currently, these are utilized for the insulation of rocket engines to prevent catastrophic breakdown if combustion gases from propellant reaches the motor case. The objective of this review is to evaluate the performance of PU–EHSM, NBR–EHSM, and EPDM–EHSM as insulators, the latter being the current state of the art in solid rocket motor (SRM) internal insulation. From our review, PU–EHSM emerged as an alternative to EPDM–EHSM because of their easier processability and compatibility with composite propellant. With the appropriate reinforcement and concentration in the rubber, they could replace EPDM in certain applications such as rocket motors filled with composite propellant. A critical assessment and future trends are included. Rubber composites novelties as EHSM employs specialty fillers, such as carbon nanotubes, graphene, polyhedral oligosilsesquioxane (POSS), nanofibers, nanoparticles, and high-performance engineering polymers such as polyetherimide and polyphosphazenes.

Smectite clay pillared with copper complexed polyhedral oligosilsesquioxane for adsorption of chloridazon and its metabolites

Copper complexed polyhedral oligomeric silsesquioxane pillared smectite clay (Cu2+@POSS_SWy-2) exhibits excellent adsorption properties for chloridazon and its metabolites.

Functionalized polyhedral oligosilsesquioxane (POSS) based composites for bone tissue engineering: synthesis, computational and biological studies

Functionalized POSS containing an isoxazolidine nucleus have been synthesized by 1,3-dipolar cycloaddition and conjugated with chitosan for bone tissue engineering applications.

Reduced graphene oxide–silsesquioxane hybrid as a novel supercapacitor electrode

Modified polyhedral oligosilsesquioxane (POSS) is used to improve the electrochemical performance of reduced graphene oxide (rGO) through the enhancement of porosity and the extension of interlayer space allowing effective electrolyte transport.