Development of Low Variability 3-D Printed Tissue Punch

Many biomedical research labs have a focus on developing models to understand how soft fibrous tissues fail. This knowledge will be used to inform methods to aid in injury prevention and healing. While many conventional materials are pre-cast or machined directly into the desired specimen geometry for mechanical testing, biological tissues must be cut to the desired shape. One of the current difficulties, along with a lack of consensus on specimen geometry, is the method used to cut the samples. Pre-machined tissue punches can be made to accurately achieve the desired geometry, but their expense and difficulties in maintenance lead many research cohorts to cut the specimens with a scalpel, or use different tissue shapes entirely. This study utilized 3D printing technology to prototype different tissue punches quickly while reducing the cost from over $1000 to less than $2 per punch. This method achieved a width variation of 3%, which was approximately equivalent to that seen by a machined punch of the same geometry. Now that a cheap, reliable, and accurate way to obtain the desired specimen shape has been found, biomedical labs will have access to a repeatable method of tissue sample preparation