3D printable millifluidic vacutainer for medicine in spaceflight

grabcad

This is a solo project by me, a student of the Friedrich-Alexander-Universität Erlangen-Nürnberg. Disclaimer: This is a medical device that is still under development and testing! It should not be used in any way under any circumstances for diagnostic procedures, yet.The designs aim is to overcome the need of invasive blood taking through venipuncture. Puncture of the finger tip with blood lancets and blood capturing with glass capillaries is superior to invasive techniques in neonates, patients suffering from obesity or fear of needles, those who are self-testing or elderly with fragile veins. However, the conventional method of capillary blood taking is prone to cause more accidents that can lead to transmission of infectious diseases when handling patients with HIV or HB etc. In contrast to the difficult feasibility when using glass capillaries, the presented design offers an integrated capillary system for blood taking with a capture device for storage, shipping and automatic processing of patient samples that is safe and easy to use. The device was designed to be printed on SLA and DLP machines to sufficiently reproduce the capillary system at 100um layer height. SLA and DLP systems are known to have good accuracy whereas the voxel/staircaise effect is lower in SLA machines. DLP machines however tend to produce parts faster when it comes to large amounts because of the all-at-once light exposure of the liquid resin in the resin vat. Biocompatibility is achieved by using biocompatible (additionally sterilizable) resins that fit ISO norms (e.g. EN-ISO 10993-1:2009/AC:2010) and/or approved by national agencies for medical use.Version 1:Transfer of blood from the capillary system is done by inserting the eppendorf tube like storage system into the capillary device. The total maximum volume of blood that can be captured is close to 1ml. It must be noted that yet further post processing of the printed parts is needed by adding a silicone layer onto the storage tube and applying negative pressure to enable transfer of the blood. Despite that the fully additive manufacturing workflow can easily be achieved when printing a plug with silicone like or flexible material. A simple boolean operation from the CAD files would create a tight-fitting plug for the storage tube that could be printed contemporaneous. The storage tube is punctured by the needle – which is also printed – in the capillary device. This encased and printed needle ensures safe blood t...