The generic term biomaterial refers to any biological material used in an experiment. Biomaterial is divided in three main components, biosources, samples and extracts. The biomaterials can then be subclassified further by the use of subtypes (see Chapter 12, Item subtypes and categories). BASE has, for example, defined two extracts subtypes: Labeled extract (used in microarray experiments) and Library (used in sequencing experiments). The order used in presenting those entities is not innocuous as it represents the sequence of transformation a source material undergoes until it is in a state compatible for further exeperimental processing. This progression is actually mimicked in the BASE Biomaterial LIMS menu again to insist on this natural progression.

BASE allows users to create any of the these entities fairly freely, however it is expected that users will follow the natural path of the laboratory workflow.