Ender VX-500

thingiverse

This page provides the model files of an open source 3D-Printer RNA extraction apparatus named the "Ender VX-500". This machine runs a semi-automated workflow for paramagnetic bead-based extraction of SARS-CoV-2 RNA from upper respiratory samples using readily accessible reagents. This innovation can deliver high-performance, low-cost and rapid molecular diagnostics for COVID-19. The platform essentially consists of a Creality3D Ender-3 printer repurposed by installing three different custom designed interlocking attachments on the printer's extruder mounting mechanism. A 3D print “job” can be executed on the printer which will emulate the movements required to make the magnetic combs on the mounted attachments run a paramagnetic bead-based RNA extraction protocol. The resulting RNA from the platform is amenable to any downstream molecular applications including RT-qPCR, LAMP or genome sequencing. A single instrument run by one operator can process 72 specimens per hour. In high-throughput mode a team of 4 operators, can process up to 384 specimens per hour on 4 Ender VX-500 machines. The platform is truly ultra-low cost. Each Ender VX-500 costs approximately 300 US$ and the required modifications can be printed from the instrument to convert it into the RNA extraction robot. All the required reagents are readily available and amount to a cost of about 1US$ per RNA extraction. So, for less than 2500US$ it is possible to build the lab infrastructure capable of testing 3000 specimens per day. The “adaptor” can be assembled directly on the extruder’s mounting mechanism using the same four bolts that attach the heated nozzle and its fan shroud. The adaptor is equipped with a double trapezoidal lock system which allows different attachments to be mounted reproducibly onto the adapter. The “tube-holder” can be mounted onto the adaptor using this toolless locking mechanism. The two pieces can furthermore be firmly locked into position by inserting an Allan wrench -supplied in the Ender-3’s assembly toolkit- through a set of overlapping holes provided in both parts. The bottom of the tube-holder is equipped with three rows of eight holes that accept and tightly hold the caps of a specific rigid 8-tube 0.2 mL PCR strip (SSIbio - Ref. 3247-00). A set of three “magnetic combs” can be inserted through the tube-holder directly into the bottom of the 8-tube strips. Each inserted magnetic comb is locked into position by a set of two rods on the tube-holder that tightly fit a compatible set of holes on the combs. The tips of the magnetic combs are equipped with cylindrical neodymium rear-earth magnets (Amazing Magnetics - Ref. R125-094). We designed an accessory “Magnet loader” that assists with accurately gluing the magnets onto the tips of the magnetic combs. During the automated extraction the magnets are shielded from direct contact with the RNA-binding paramagnetic beads by the certified RNase-free 8-tube strips. A short Ender VX-500 introduction video: https://youtu.be/XiqcePzt0X8 A short video on the operation / cleaning of the Ender VX500: https://youtu.be/aMUB5sEuJ2U A detailed protocol on the use of the Ender VX-500 machines: https://tinyurl.com/yyhyqsy6