Abstract: A method for analyzing the content of boron in a cathode active material is disclosed herein. In some embodiments, a method comprises (S1) introducing boron into a cathode active material to prepare a cathode active material sample, (S2) separating a first liquid layer and a first precipitate by dissolving the sample in water, treating the first liquid layer with acid to form a first resulting solution, and measuring the boron concentration in the first resulting solution by inductively coupled plasma optical emission spectroscopy (ICP-OES), (S3) separating a second liquid layer and a second precipitate by dissolving the first precipitate in water, treating the second liquid layer with acid to form a second resulting solution, and measuring the boron concentration of the second resulting solution by ICP-OES, and (S4) measuring the boron concentration of a third resulting solution, obtained by adding acid and hydrogen peroxide to the second precipitate, by ICP-OES.

Abstract: Provided is a process for purifying a vancomycin wet body, comprising: dissolving a wet body obtained from a microorganism-fermented solution containing vancomycin into a water soluble solvent to a concentration of about 1 to 40 g/L and carrying out reverse osmosis filtration; and carrying out lyophilization of the filtered vancomycin. The process for purifying a vancomycin wet body provides high-purity vancomycin, while avoiding degradation of stability during a drying step.

Abstract: Provided is a process for purifying a vancomycin wet body, comprising: dissolving a wet body obtained from a microorganism-fermented solution containing vancomycin into a water soluble solvent to a concentration of about 1 to 40 g/L and carrying out reverse osmosis filtration; and carrying out lyophilization of the filtered vancomycin. The process for purifying a vancomycin wet body provides high-purity vancomycin, while avoiding degradation of stability during a drying step.