Opentrons pipettes are designed and tested to handle a wide range of aqueous solutions common to biochemistry. But, they haven't been tested for use with solvents and other non-aqueous chemicals.
What materials are used in Opentrons tips?
Opentrons tips are made from 100% polypropylene.
What materials are used in Opentrons pipettes?
The parts of the pipette that might touch liquid or vapor are made from:
PC-ABS (external & internal housing)
NBR (internal plunger O-ring)
Silicone (external O-ring)
Only the pipette tips are designed to touch the liquid. If liquid enters the inside of the pipette, it can permanently damage it.
Never use acetone with Opentrons pipettes! It will permanently damage them. PC-ABS plastic is extremely sensitive to acetone.
I'm a biologist. My protocol calls for 100% methanol or ethanol. What should I do?
While Opentrons pipettes can handle 100% ethanol or methanol, the vapor can internally damage them over time.
If you can, prepare a stock solution by hand at a lower concentration before putting it on the robot. Using diluted alcohol solutions will also improve volumetric accuracy, because of the reduced vapor pressure.
If you must handle 100% alcohol on the robot, we recommend you use a dedicated pipette, as the alcohol vapor will cause it to wear out faster than pipettes used only with aqueous solutions and you may notice reduced volumetric accuracy over time.
I'm a chemist. Can I use Opentrons pipettes with volatile organic solvents?
We don't recommend it. The pipettes weren't designed or tested to be used with organic solvents. PC-ABS has very limited chemical resistance, particularly to aliphatic, aromatic, and chlorinated hydrocarbons as well as alcohols, ketones, esters, and glycols.
Since the internal plunger of the pipette is made from PC-ABS, even though it does not contact the liquid, it is susceptible to damage over time from solvents with a high vapor pressure. Because the tips are polypropylene, it may be possible to handle some volatile solvents initially, but the vapor created during aspiration will damage the internal PC-ABS parts, degrading the performance of the pipette over time and eventually breaking it. Depending on the solvent, this might happen after the first use, or it might only happen after repeated use.
The external surfaces of the pipette are also made from PC-ABS and will be damaged if they accidentally touch your solvent.
Ultimately, it's your responsibility to determine if your solutions are compatible with the materials in the OT-2. We recommend consulting a chemical compatibility database to determine any possible interactions before using solvents on the OT-2.