We mostly just got rid of all the stuff we didn’t need from a standard gel setup. Turns out you don’t need >200 mL of running buffer, or >100 V between electrodes, or >$1k to spend on a gel box – you just need a 3D printer and a different design. How satisfying!

With a range of designs, we resolved on/off nanoswitches in ~1 minute at 75 volts or in ~45 minutes at 8 volts. We also showed that we could image the gel with a cell phone camera, LED flashlight, and filter paper...

One huge advantage of smaller box is the same voltage gives a larger electric field (closer electrodes), enabling either lower voltage operation or faster separation at the same voltage. 3D printing allowed us to quickly test various inter-electrode distances...

Side note for those interested in electrophoresis – this design is cheap and easy! Prints in <1 hour on a dual-extruder printer for ~30 cents of material (>1000x less than any gel box from lab supply stores). We also printed replacement gel combs which performed identically to the $50+ combs...

Postdoc Lifeng Zhou 3D printed mini boxes and added wire electrodes with early encouraging results that we could eliminate much of the gel apparatus. Later Andrew Hayden found conductive filament, and 3D printed the whole gel box with electrodes. It works as well as our conventional gel system!

It started because: 1) we noticed that typical gel equipment was overkill for our application, and 2) we heard criticisms that DNA nanoswitch sensing could never become “point of care” due to reliance on electrophoresis. This combined two passions - design minimalism and proving critics wrong :)

This dates to ~2019 - we asked whether we could redesign gel electrophoresis to better suit our DNA nanoswitch sensors (which shift migration based on molecular detection). We ended up with a fully 3D printed mini-gel costing ~30 cents, operable with batteries, and capable of detection in minutes…

A lot of fun to "get the band back together" so to speak. I realized it's my first "first author" paper in about a decade :)

We have a PDF on our lab website if people have access limitations here (though I think it's supposed to be open access).

www.halvorsenlab.com/publications

We discuss the history and landscape of multiplexed single-molecule force spectroscopy, including developments in instrumentation, molecular tools, surface chemistry, and analytical methods. We explore emerging applications and outline challenges and opportunities in this evolving field...

thx, looks like the same issue here. I'll reach out to the MIRA staff after the holidays.

imagining a NSF PO handing a VC bro the stack of 10-to-15 proposals they'll have to be ready to discuss, then explaining that they'll be paid $600 for the three days of the panel meeting

Oh wow great, thanks for sharing - been waiting with some anxiety for this