What is the fine-grained topic of the following text: The NxStage System One Express System uses premixed fluid bags that are manufactured to European and U.S. Pharmacopeia standards, are terminally sterilized and non-pyrogenic (<0.25EU/mL), and also meet ISO 10993 Biological Evaluation of Medical Devices. Only return the topic.
NxStage System One Express System's premixed fluid bags' standards and properties.