Sonorex digitec ultrasonic bath

Fibrillated samples were sonicated for 10 min in a Sonorex Digitec ultrasonic bath (Bandelin, Berlin, Germany) and diluted to 15 µM in Tris buffer (50 mM, pH 7.5). Spectra for fibrils and monomers were recorded on a Chirascan CD spectrophotometer (Applied Photophysics, Surrey, UK) in a 1 mm cuvette between 200 and 260 nm with 3-nm bandwidth at 25 °C and three accumulations.

Dispersions of aqueous GO solutions (or their derivatives) were accordingly done using a Sonopuls mini20 ultrasonic homogenizer coupled with a 2.5 mm diameter tip (Bandelin electronic GmbH & Co. KG, Berlin, Germany), for 15 min, 70% input and 0.5 Hz, at room temperature, whereas mixing of solutions was done with a standard vortex mixer. Dispersions of GO-g-AEMA in the DEAEMA monomer were performed in a model Sonorex Digitec ultrasonic bath (Bandelin electronic GmbH & Co. KG, Berlin, Germany), for 15 min. Thermal control of reactions was done with a model Pura 4 water bath (Julabo GmbH, Seelbach, Germany) coupled to a test tube rack.

Polyphenolic extract was obtained from Salvia officinalis (common sage) by ultrasound-assisted extraction (Bandelin Sonorex Digitec ultrasonic bath—Berlin, Germany) at 40 °C, in absolute ethanol, at a vegetal material/solvent ratio of 1/30 (w/v). The extraction was carried out in three 15 min. steps, with solvent replacement in each stage. The extract was evaporated using a rotary evaporator (RE100-Pro, DLAB Scientific, Beijing, China) until it reached a constant mass and then was redissolved at a desired concentration. After preparation, Salvia officinalis polyphenolic extract (denoted S) was adsorbed into functionalized MSN mesopores through impregnation, followed by solvent evaporation under vacuum. First, the mesoporous carriers were dried under vacuum, at room temperature, for 12 h, and then the corresponding volume of polyphenolic extract (15 mg/mL) was added to the support to obtain composites with a theoretical content of 25 %wt extract. The polyphenolic-extract-loaded MSN were denoted S@MSN-x, where x = NH₂ or COOH.