Microwave-Assisted Sol–Gel Preparation of the Nanostructured Magnetic System for Solid-Phase Synthesis

Abstract

This work describes a new synthesis method for core–shell magnetite nanoparticles with a secondary silica shell, functionalized with a linker system (Fe3O4-PABA-SiO2-linker) using a microwave-assisted heating technique. The functionalized solid nanomaterial was used for the nanophase synthesis of peptides (Fmoc route) as a solid support. The co-precipitation method was selected to obtain magnetite nanoparticles and sol–gel technique for silica coating using a microwave-assisted (MW) procedure. The magnetic properties of the nanoparticle core offer the advantage of a quick and easy alternative for the magnetic separation of the product from the reaction mixture, facilitating all the intermediary washing and separation operations. The intermediate and final materials were analyzed by advanced characterization methods. The effectiveness of the nanophase peptide synthesis using this nanostructured material as solid support was demonstrated for a short peptide sequence.

Synergistic Antimicrobial Activity of Magnetite and Vancomycin-Loaded Mesoporous Silica Embedded in Alginate Films

“…The surface functionalization was an important target, as it prevents the agglomeration of the nanoparticles, thus allowing a homogeneous particle dispersion within our final system, the magnetic film. Fe 3 O 4 and Fe 3 O 4 /malic samples revealed a mutual peak corresponding to Fe–O stretching vibration, at ~550 cm −1 , normally reported in previous studies [ 38 , 39 ]. The large absorption bands centered around 3345 cm −1 , present in both samples, are assigned to –OH stretching vibrations, while Fe 3 O 4 additionally presents a very faint absorption band at 1630 cm −1 , attributed to –OH bending vibrations.…”

Green synthesis of silica gel adsorbents: microwave boosts silanol groups for improved moisture uptake

“…Microwave-assisted synthesis has emerged as a powerful tool for material synthesis (Zengin et al, 2023) (Santos et al, 2021) due to its rapid processing, lower energy consumption, and enhanced control over material properties (Istrati et al, 2021) (Bucek et al, 2019). However, limited research has been conducted on tailoring the properties of silica gel, specifically the silanol group content, through microwave synthesis for improved moisture adsorption (Zhuravlev & Potapov, 2006).…”

Highly Selective Physical/Chemical CO2 Separation by Functionalized Fe3O4 Nanoparticles in Hollow Fiber Membrane Contactors: Experimental and Modeling Approaches

“…For example, they demonstrated that although Fe 3 O 4 -P resulted in the CO 2 absorption capacity of pure water and NMP solution increasing roughly to 25.07 and 15.88%, its performance was truly negligible when it was used in sulfinol. ,, Likewise, Arshadi et al used Fe 3 O 4 @SiO 2 -NH 2 nanodispersion at a high concentration of 0.4 wt %, which promoted CO 2 uptake up to 70% and with respect to pure water as a base solvent in a bubble column system as a semicontinuous mode . The reason for the high stability of Fe 3 O 4 @SiO 2 NPs was explained by Istrati et al Based on their report, the SiO 2 layer on the surface of Fe 3 O 4 can result in a steric barrier against core agglomeration, preventing interactions between nanoparticles, which plays a key role in increasing the stability of the Fe 3 O 4 NPs in the solution. In another study, Irani et al employed amino-functionalized graphene oxide nanodispersion in a bubble column absorber and increased CO 2 uptake up to 16.2% with respect to MDEA solution as a base solvent .…”