Stock solutions: Prepare stock solutions of individual proteins by dissolving the whole content in a vial with water to a concentration of 20-30 mg/ml.
If the diluted stock solution of the protein is not intended to be used in a protein mix, aliquot into individual portions and store at -20°C.
Protein mixes: Calculate the volume needed from each protein stock solution to achieve the desired final concentration. Mix the appropriate proteins and dilute with running buffer. Aliquot in appropriate portions and store at -20°C.
Gel Filtration Calibration Kits (HMW and LMW) contain protein standards and have been developed for use in size exclusion (gel filtration) chromatography. Kits containing protein standards for molecular weight determination by polyacrylamide gel electrophoresis are also available from Cytiva.