A system for reprocessing and sterilizing a previously used endoscope having at least one lumen is disclosed. The reprocessing system includes a reaction chamber into which individual chemical components of a sterilant are transferred by pneumatic force. The system includes a central processor which controls the asynchronous reprocessing and sterilization of at least two endoscopes. A novel sterilant is also disclosed. Also disclosed is a combination of the sterilization device and the sterilant and methods of using the same.