Bioxtra

The determinations were performed using analytical grade reagents intended for liquid chromatography: hydrochloric acid, formic acid, ethanol by Sigma-Aldrich; methanol by J.T. Baker Malinckrodt Baker B.V. Holland. Acetonitryl CHROMASOLV^® gradient grade, ≥99.9% by Sigma-Aldrich. Sugar analytical standards by BioXtra, ≥99% HPLC grade, were obtained from Sigma-Aldrich. Deionized water was obtained using a HLP 5P deionizer manufactured by Hydrolab Polska. Oleanolic acid standard, 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) diammonium salt, 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox), 2,4,6-tri(2-pyridyl)-s-triazine (TPTZ), and 2,2-diphenyl-1- picrylhydrazyl (DPPH) were purchased from Sigma-Aldrich (Steinheim, Germany).

Coronatine (C8115‐1MG; Sigma‐Aldrich) powder was dissolved in 100% dimethyl sulfoxide (DMSO) to create a 200 μM ml⁻¹ stock that was then diluted to 3 and 0.3 μM in double‐distilled water (ddH₂O). Salicylic acid (SA) BioXtra ≥ 99.0% (S5922‐100G; Sigma‐Aldrich) was diluted in water to concentrations of 2, 0.4 and 0.2 mM. Buffer solution used was the same as the solvent for the treatment. Individual wells of 6 or 12 well plates containing three duckweed fronds were inoculated with 500 or 250 μl of phytohormone solution, respectively. Phytohormone treatments were applied just before pathogen treatment.

According to the Massart process, the CMD-coated IONs were synthesized by co-precipitation [30 (link),31 (link)]. A total of 20 mL of CMD solution (250 g L⁻¹ (CMD250); 125 g L⁻¹ (CMD125); 25 g L⁻¹ (CMD25.0); 12.5 g L⁻¹ (CMD12.5); 6.25 g L⁻¹ (CMD6.25); CMD sodium salt, BioXtra, Sigma Aldrich, Darmstadt, Germany, 39422-83-8); and 2.5 mL of aqueous 25% ammonium hydroxide solution (Aldrich Chemistry) were added to a 100 mL round-bottomed flask in a nitrogen atmosphere. The reaction was induced by adding 20 mL of an iron (II/III) solution (FeCl₂·4H₂O (1 eq., 347 mg 1.75 mmol), Emsure^TM; FeCl₃·6H₂O (2 eq., 945 mg, 3.50 mmol), Fluka Sigma Aldrich, Darmstadt, Germany) to the reaction mixture and by stirring it uniformly for one hour at a temperature of 85 °C. After the completion of the reaction, the synthesized particles were centrifuged (CMD250, CMD125) at 4000× g for 10 min or magnetically separated (CMD25.0, CMD12.5, CMD6.25) and washed with ethanol absolute (2×) and degassed using double-distilled water (ddH₂O, 2–3x) until a conductivity lower than 200 µS cm⁻¹ was obtained. The particles were stored in an N₂ atmosphere at 4 °C in degassed ddH₂O.

All materials used in this study were of analytical grade and were used without further purification. The anode active materials—the carbon-coated SiO₂ composites—were prepared via the aqueous pathway, which is a simply and eco-friendly preparation route. The preparation process of the carbon-coated SiO₂ composites is illustrated in Scheme 1. Typically, aqueous sucrose (BioXtra, ≥99.5% (GC), Sigma-Aldrich) solutions (0.04 M, 0.055 M, 0.07 M, and 0.085 M) were prepared under continuous stirring. Then, the same amount of silica (Silicon dioxide nanopowder, spherical, porous, 5–15 nm in diameter, 99.5%, from Sigma Aldrich) was added to each sucrose solution. The resulting mixture was vigorous stirring at 70 °C until water was completely evaporated. The resulting white powder was dried in an oven, under vacuum, at 70 °C for 20 h, and then carbonized in a tube furnace in argon atmosphere at 900 °C for 1 h, using a heating ramp of 1 °C·min⁻¹. Then, the prepared carbon-coated SiO₂ composite materials with different carbon content were used to prepare the anodes.

GTW and CTW were prepared by adding the WHO-prescribed dosage of sea salts (Sigma-Aldrich, product number S9883), sodium bicarbonate (BioXtra, 99.5–100.5%, CAS number 144-55-8 procured from Sigma-Aldrich), and tannic acid (ACS reagent grade, CAS number 1401-55-4 obtained from Sigma-Aldrich) or humic acid (50–60%, CAS number 68131-04-4 procured from Alfa Aesar) in DI water (see Supplementary Fig. 3a for dosages)³⁷ . To achieve turbidity of 40 NTU in CTW, Arizona Test Dust (ISO 12103-1, A2 fine test dust obtained from Powder Technologies Inc.) was added to DI water at a concentration of 70 mg/L based on calibration reported in literature⁷⁸ .

The chemical preparation of microcapsules required the following reagents:

Shell: Methyl methacrylate (MMA) (99%, contains ≤ 30 ppm monomethyl ether hydroquinone (MEHQ) as inhibitor, Sigma Aldrich, Auckland, New Zealand) and pentaerythritol tetraacrylate (PETRA) (contains 350 ppm (MEHQ), Sigma Aldrich, Auckland, New Zealand) were used as a monomer and cross-linking agent respectively in order to obtain proper shells for MPCM.

Free radical thermal initiator: Luperox^® A75, Benzoyl peroxide (BPO) (75%, contains 25% water, Sigma Aldrich, Auckland, New Zealand) was used as free radical thermal initiator.

Surfactants: Polyvinyl alcohol (PVA) (M_w 85,000–124,000, Sigma Aldrich, Auckland, New Zealand) and sodium dodecyl sulfate (SDS) (BioXtra, 99%, Sigma Aldrich, Auckland, New Zealand) were used as a non-ionic and ionic surfactant, respectively.

PCM: a commercial paraffinic PCM, Rubitherm^® RT 21 (T_m = 21 °C, ΔH_m = 135 J·g⁻¹, Rubitherm^® Technologies GmbH, Berlin, Germany) was used.

The bulk density of M-2 microcapsules is 0.496 g·mL⁻¹. The commercial MPCM, Micronal^® DS 5008 X (BASF^®), was also selected for characterization and was compared with the microcapsules produced in this work. This sample is also composed by an acrylate shell and organic PCM in the core [13 (link)], and its bulk density is 0.445 g·mL⁻¹.