Aluminum (as gel or salt) is used in vaccines as an adjuvant. This helps to get a stronger immune response. The amount of aluminum in vaccines is regulated e.g., by USP. According to USP maximum amounts of Al3+ in a vaccine dose lay between 0.85 and 1.25 mg. This work describes the determination of aluminum as the 8-hydroxyquinoline complex by ion chromatography with UV/VIS detection.