disposable electroelution system
DESCRIPTION
Demonstrates an extreme low cost solution to prep-scale oligo electroelution that John Picuri and I came up with to save time and improve yield on our DNA prep process.TRANSCRIPT
The Incredible, Disposable,
Electroelution System.
All the benefits of electro-elution without the hassle of a setting up and cleaning a full rig and trap.
5/7/07 Brian Frezza, John Picuri, and The TSRI Instrumentation and Design Lab
Non-disposable Parts
Acrylic Sheath
Plastic CapRubber Cap
Rubber O-Ring
Acrylic O-Ring
Acrylic Sheath
Plastic Cap
Acrylic O-Ring
Rubber O-Ring
Rubber Cap
Required Equipment
DisposableTea Bag Paper
Disposable20mL Syringe
2 Platinum Electrodes
Disposable 50mL Beaker
DisposableBT1 Membrane
Step 1: Cut 20mL syringe at the 13mL mark.Cut here
Step 2: Place Acrylic O-Ring on Tea-bag paper and fit into top of syringe.
Step 3: Cut away excess Tea-bag Paper and slide Acrylic O-Ring to the
bottom of the syringe
Step 4: Remove BT1 Membrane from package and punch out a size 8 circle.
Step 5: Thread the acrylic sheath into the small hole in the plastic Cap. Then place the rubber O-ring on top of acrylic sheath, and the circular BT1
membrane on top of both.
Plastic Cap
Acrylic sheath
Rubber O-ringCircular BT1 Membrane
Step 7: Fit the green rubber cap on top of the circular BT1 membrane such that it seals tightly. Then invert the plastic cap and place on top of
disposable 50mL beaker.
Step 8: Fill the beaker with ~30mL of TE (Tris, EDTA, pH 7.5) buffer. Then gently fill the acrylic
sheath full of TE with a pipette.
Step 8: Insert the prepared syringe from step 3 into the large hole in the plastic cap and then pipette
the syringe full of TE.
Step 9: Place gel slice with DNA in 10mL falcon tube and crush into little pieces with a glass rod.
DNA dyed pink (Cy3)for easy visualization
Step 10: Invert the tube over the syringe and gently tap to transfer crushed gel.
Get psyched, you’re almost ready to elute!
Step 11: Place positive electrode into the acrylic sheath, and negative electrode into the syringe.
Step 12: Check to make sure that both electrodes are submerged and that there are no air bubbles
blocking the opening to the syringe or the sheath.
Both electrodes submerged
BAD! Air bubble, remove by taping
Negative electrode (repels DNA)
Positive Electrode(attracts DNA)
Step 13: Turn the power on and adjust to 250V. Wait ~5 min per 5mL crushed gel for complete
elution.
The BT1 membrane allows salt to pass though it but NOT DNA. So when you
turn on the juice, the DNA will be pulled out of the gel into the beaker, but
cannot contact the positive electrode since its protected by the sheath and
BT1 membrane.
Watch the DNA elute!
Watch the DNA elute!
Watch the DNA elute!
Watch the DNA elute!
Step 14: Turn off power, remove electrodes and plastic cap. DNA remains in the beaker.
No DNA (no color)
DNA!
Note, there really is no DNA in the sheath or syringe
No DNA (no color)
Where’s all the DNA? In the beaker, ready to go!
Step 15: Remove and wash, O-rings, sheath, and cap with water and Methanol (optional)
Step 16: Toss out all that other junk. It’s disposable!
Step 17: Marvel at how much time you just saved, and you’re greatly improved yields!
Remaining DNA in gel after a 48 Hour “Crush and
Soak” procedure.Check out all that hard-
earned DNA (pink) you’re going to have to toss.
Remaining DNA in gel after ~5 min of electro elution.
Can you see any DNA (pink)?
Electroelution Comparison:
Retail Price: $1,683.55(starter set, includes what’s show from VWR.com)
Setup Time: ~20 minCleanup time: ~30 min
The only commercially available electroelution system:
Schleicher & Schuell’s Elutrap®Our System:
Materials Cost: ~$8.00Setup time: ~15 min
Cleanup time: ~ 5 min
Further Optimization
• Mass production of the syringe prepared in steps 1-3, and the sheath prepared in steps 4-7 would reduce prep time to ~3 min.
• If the acrylic sheath was made of plastic it’s cost should be low enough (< $1) that all components but the beaker cap could be disposable reducing the cleanup time to ~30 seconds.
• If commercially produced, the electrodes on the cap should be protected by an insulated plug to make it more difficult to shock yourself.
• All said and done, the setup cost for the cap w/guides and electrodes would be ~$10, and a kit containing all other disposable peaces would cost < $1 per run.