Lyophilized bsa

Lyophilized BSA (essentially globulin and fatty acid free, ≥ 99% pure) was purchased from Sigma-Aldrich (St. Louis, MO, USA). Ethanol absolute 99.8% (C₂H₅OH), 1-propanol (C₃H₈O) absolute 99.5%, and 2-propanol absolute 99.5% were obtained from VWR Chemicals (Fontenay-Sous-Bois, France). D-(+)-glucose (≥ 99.0%), sucrose (≥ 98.0%), and D-(+)-maltose monohydrate (≥ 99.0%) were obtained from Merck (Darmstadt, Germany). Pierce BCA protein assay kit was sourced from Thermo Scientific (Rockford, United States of America).

Lyophilized BSA (Sigma–Aldrich, catalog number: A6003) was dissolved in Reaction buffer (50 mM Tris-HCl, pH7.5, 150 mM GluK, 5 mM GluMg) at approximately 100 g/L. Then, the buffer was exchanged with Reaction buffer to wash out residual molecules using Amicon Ultra-0.5 centrifugal filter unit 50 kDa. After washing steps, the concentration of BSA was measured by Bradford Assay. Ficoll70 and Dextran70 (Sigma–Aldrich) were dissolved in Reaction buffer, and their concentration was calculated from the weight of crowding agents and total volume of the solution (typically, the final concentration of the solution was 300–500 g/L). Crowding solutions were stored at −20 °C until further use.