What this protocol does
After in-vitro transcription (IVT) and DNase polishing, the reaction is a mixture of target mRNA plus polymerase, residual template, unincorporated NTPs, salts, and short abortive transcripts. This protocol automates the SPRI magnetic-bead cleanup that recovers clean, full-length single-stranded mRNA in nuclease-free water — concentrated and ready for downstream formulation — entirely in 96-well plate format, with no centrifuge or vacuum step.
It runs the standard 1.8× bead cleanup on the Undergrad with the Accuris AutoMATE 96 and an on-deck magnet, and vision-verifies the magnet and wash steps where yield is usually lost.
Where it sits
This is the purification step between IVT / DNase and downstream formulation in an mRNA production workflow.
From intent to atomic steps
Layer 1 · Intent — plain languageDescribe the automated mrna cleanup (spri) the way you would brief a labmate — no scripting, no deck programming.
2 Protocol stages3 Robot actions4 Atomic actions — vision-verified
1Bind~7 min
Vortex the bead stock to homogeneity, then add 1.8× SPRI beads (~80 µL to a ~44 µL reaction), mix ~10 times, and bind 5 min at room temperature.
◉Vision: Vision confirms even bead dispense and mixing across the plate.
2Capture3–5 min
Move the plate to the magnet and let beads pellet until the supernatant is clear, then aspirate and discard the supernatant.
◉Vision: Vision verifies the supernatant is clear before aspirating, so beads aren't pulled off.
3Wash (x2)~5 min
On-magnet, dispense 150–190 µL fresh 70% ethanol, settle 30 s, and aspirate to waste. Repeat once.
◉Vision: Vision checks the wash dispense and full aspiration without disturbing the pellet.
4Air-dry3–5 min
Air-dry the bead pellet on the magnet 3–5 min — just until no visible ethanol, not cracked.
◉Vision: Vision watches for residual ethanol and over-drying.
5Elute~5 min
Move off the magnet, add nuclease-free water (~20–40 µL), and mix until the pellet is fully resuspended; elute 2–5 min at room temperature.
6Recover~4 min
Return to the magnet, settle, and transfer the clean eluate to a fresh collection plate, leaving beads behind. Seal and hold at 4°C.
◉Vision: Vision confirms the eluate transfer leaves the bead pellet behind.