A stainless-steel mortar, pestle and sleeve design for the efficient fragmentation of ancient bone

Abstract

Ancient DNA (aDNA) bone extraction protocols routinely require the fragmentation of larger bone pieces into smaller pieces or powder prior to DNA extraction. To achieve this goal, different types of equipment such as oscillating ball mills, freezer mills, mortar and pestle, or drills can be used. Although all these approaches are suitable, practical drawbacks are associated with each method. Here, we present the design for a stainless-steel mortar and pestle, with a removable sleeve to contain bone material. The tool readily comes apart for ease of cleaning and its simplicity allows university workshops equipped with a lathe, boring tools and milling machine to make these components at local expense. We find that this design allows for the controlled fragmentation of ancient bone and that it significantly improves our sample throughput. We recommend this design as a useful, economical addition to existing laboratory equipment for the efficient handling of ancient bone.