Milli q lab water system

Materials for synthesis and reagents for sonochemical reaction catalytic tests (set up scheme shown in Scheme 1) with 4-hydroxy-3,4-dimethoxybenzylalcohol were purchased from ThermoFisher (Waltham, MA, USA). LUDOX HS-40 colloidal silica (40 wt% suspension in water) and cyanamide (99%) were purchased from Sigma Aldrich (St. Louis, MO, USA). Sucrose and sodium hydroxide were purchased from POCH (Gliwice, Poland). D-glucosamine hydrochloride (≥98%) and low-molecular-weight chitosan (100–300 cps) were purchased from Pol-Aura. Acetic acid (99.5%) was purchased from ChemPur (Karlsruhe, Germany). Milli-Q water was purified using a Millipore Milli-Q lab water system (Burlington, MA, USA). The carbonaceous materials were characterized by nitrogen physisorption, thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR). The equipment used and details of the analysis are shown in the Supporting Information.

All chemicals were obtained from Fisher Scientific (Pittsburgh, PA, USA) or Sigma Aldrich (Milwaukee, WI, USA). All media were made with distilled water purified with a Millipore Milli-Q lab water system (Burlington, MA) to a resistivity of 18.2 MΩ.cm. LB media used for pre-growth was made of 10 g/L tryptone, 5 g/L yeast extract, and 10 g/L NaCl dissolved in Milli-Q water, which was then sterilized by autoclaving. M9 minimal glucose media was used as the “complete media” in this study, from which C-starved, N-starved, P-starved, and Mg²⁺-starved versions were derived. The compositions of the different media are provided in Supplementary Table S3.
LB-agar plates were made with 25 g/L pre-mixed LB Miller broth and 15 g/L agar, which was autoclaved. For mutant selection, 50 μg/mL KAN was used. For lexA3 mutant selection M9 minimal agar plates made with 6.78 g/L Na₂HPO_4, 3 g/L KH₂PO₄, 1 g/L NH₄Cl, 0.5 g/L NaCl, 0.011 g/L CaCl₂, 0.24 g/L MgSO_4, and 10 mM maltose as the sole carbon source were used. For all wash steps, phosphate buffered saline (PBS) was prepared from autoclaved Milli-Q water and a 10X stock, followed by sterile-filtering (0.22 μM pore size). The 10X stock contained 98.9 g of powder (81% NaCl, 14% Na₂HPO₄, 3% KH₂PO₄, and 2% KCl by weight) in 1 L of Milli-Q water.

Polyethylene glycol (PEG-8000, Lot# SLBW6815) with molecular weight (Mw) of 8000 Da, polypropylene glycol (PPG-400, Lot# BCBT9613) with Mw of 400 Da, and polyvinylpyrrolidone (PVP-40,000 Lot# WXBD4555V and Lot# WXBB3898V) with Mw of 40,000 Da were obtained from Sigma-Aldrich (St. Louis, MO, USA). Polyacrylamide (PAM-10,000, Lot# A804225) with Mw of 10,000 Da (50% wt. in water solution) was purchased from Polysciences, Inc. (Warrington, PA, USA). Ucon 50-HB-5100 (Ucon-3930, Lot# SJ1955S3D2), a random copolymer of 50% ethylene oxide and 50% propylene oxide, with Mw of 3930, was purchased from Dow-Chemical (Midland, MI, USA). Sodium sulfate, sodium phosphate monobasic, sodium phosphate dibasic, and KCl of analytical reagent grade were purchased from Fisher Scientific (Waltham, MA, USA) and used without further purification. Ultrapure water purified using a Millipore Milli-Q lab water system was used for preparation of all solutions.
Dinitrophenylated (DNP-) amino acids (DNP-alanine, DNP-norvaline, DNP-norleucine, and DNP-α-amino-N-octanoic acid) were purchased from Sigma-Aldrich. The sodium salts of the DNP-amino acids were prepared by titration.

Nitrogen-15 isotopically labeled human Aβ peptides [15N] Aβ1–40 and [15N] Aβ1–42, as well as synthetic human Aβ peptides Aβ1–40 and Aβ1–42, were obtained from rPeptide (Athens, GA, USA). Milli-Q lab water system (Millipore, Billerica, MA, USA) was used to obtain water for the mobile phase and sample preparation. Acetonitrile, ammonium hydroxide, and ortho-phosphoric acid were purchased from Merck (Darmstadt, Germany). Potassium dihydrogen phosphate and sodium chloride were purchased from Applichem (Darmstadt, Germany). Methanol, potassium chloride, and guanidine HCl were purchased from VWR (Pennsylvania, USA). Sodium hydroxide and sodium bicarbonate were sourced from Sigma (Missouri, USA). Magnesium sulphate and calcium chloride were purchased from Fluka (Germany). Pooled human CSF was purchased from Innovative Research (USA). Artificial CSF was prepared from 122 mM NaCl, 3 mM KCl, 0.4 mM KH2PO4, 1.3 mM CaCl2, 25 mM NaHCO3, 1.2 mM MgSO4, and 0.4 % bovine serum albumin [13] (link), [20] (link).