Orienting the Pore Morphology of Core-Shell Magnetic Mesoporous Silica with the Sol-Gel Temperature. Influence on MRI and Magnetic Hyperthermia Properties

Abstract

The controlled design of robust, well reproducible, and functional nanomaterials made according to simple processes is of key importance to envision future applications. In the field of porous materials, tuning nanoparticle features such as specific area, pore size and morphology by adjusting simple parameters such as pH, temperature or solvent is highly needed. In this work, we address the tunable control of the pore morphology of mesoporous silica (MS) nanoparticles (NPs) with the sol-gel reaction temperature (Tsg). We show that the pore morphology of MS NPs alone or of MS shell covering iron oxide nanoparticles (IO NPs) can be easily tailored with Tsg orienting either towards stellar (ST) morphology (large radial pore of around 10 nm) below 80 °C or towards a worm-like (WL) morphology (small randomly oriented pores channel network, of 3–4 nm pore size) above 80 °C. The relaxometric and magnetothermal features of IO@STMS or IO@WLMS core shell NPs having respectively stellar or worm-like morphologies are compared and discussed to understand the role of the pore structure for MRI and magnetic hyperthermia applications.

Peptide Hydrogels Assembled from Enzyme-Adsorbed Mesoporous Silica Nanostructures for Thermoresponsive Doxorubicin Release

“…The first step of this work was to graft IBAM groups at the surface of the STMS NPs and characterize the features of this grafted organic layer by transmission and scanning electron microscopies (TEM-SEM), thermogravimetric analysis (TGA), and porosimetry. STMS nanoparticles were synthesized by using tetraethoxysilane (TEOS) as a silica precursor and cetyltrimethylammonium, tosylate (CTATos) as a structure-directing agent as reported in previous studies. , TEM and SEM were used to characterize the structures of synthesized STMS particles, as shown in Figure S1. It can be clearly observed from the TEM/SEM images that the STMS NPs are highly monodisperse, showing a homogeneous radial stellate mesoporous structure with an average size of 90 ± 7 nm.…”

Protein sustained release from isobutyramide-grafted stellate mesoporous silica nanoparticles

“…The protein release was also investigated at 25, 37 and 45 °C in order to get insights on the release profiles at respectively a preparation temperature, the human biological temperature and a characteristic temperature of magnetic hyperthermia. Indeed, iron oxide NPs with controlled size and shape are good heating agents under magnetic stimuli (among other stimuli) ( Cotin et al, 2018 ) and the addition of a stellate silica shell around these iron oxide NPs was already reported and showed good heating properties too ( Adam et al, 2021 ; Perton et al, 2019b ). Thus, a combination of this magnetic core and our protein loaded-STMS shell could be considered to couple different therapeutic effects in a single nanocarrier.…”

Structural impact of carbon nanofibers/few-layer-graphene substrate decorated with Ni for CO2 methanation via inductive heating

“…Vials adapted for SAR measurements were filled with 1.0 mL of each sample dispersed in toluene at 50 mg ml -1 by sonication and then were submitted to alternating magnetic field at 796 kHz and 200 G (15.9 kA m -1 ). The temperature change was recorded for 150 s. A second order polynomial function allowed to fit the temperature profile and to determine [dT/dt] t = 0 as described by Perigo et al [66] and in previous works [67,68] to evaluate the SAR value by using the following equation:…”