After three years of not touching a single bit of glassware, I have recently donned on the white coat and stepped back into the Chemistry lab. I am doing this for my PhD project to make some of the follow-up compounds that my pipeline suggests. However, this time there is a slight difference – I am doing reactions with the aid of a liquid handler robot, the Opentrons. This is the first encounter that I have with (semi-)automated synthesis and definitely a very exciting opportunity! (Thanks to my industrial sponsor, Diamond Light Source!)
Opentrons is primarily used by biologists and their goal is to make a platform to easily share protocols and reproduce each other’s work (I think we can all agree how nice this would be!). They provide a very easy to use API, wishing it to be accessible to any bench scientist with basic computer skills. From my experience so far, this has been the case as I found it extremely easy to pick up and write my own protocols for chemical reactions. Here is the command that will: (1) pick up a new pipette tip; (2) transfer a volume from source1 to destination1; (3) drop the pipette tip in the trash; (4) pick up a new pipette tip; (5) transfer a volume from source2 to destination2; (5) drop the pipette tip in the trash.
pipette.transfer(volume, [source1, source2], [destination1, destination2], new_tip=’always')
But of course not everything is plain sailing – there are many challenges you will encounter by using an automated pipette. The robot is a liquid handler – it cannot handle solids so either the solids need to be pre-weighed and/or made into solution beforehand. Further difficulties lie within the properties of the solvent it is handling, for example:
- Dripping – low boiling point solvents tend to drip more.
- Viscosity of liquids causes issues with not drawing up the correct amount of liquid – more viscous liquids require longer times to aspirate and if aspiration is too quick then air pockets may be drawn up.
Here is a GIF I made of a dry run I was doing with the robot (sorry for the slight shake, this was recorded on my phone in the lab… See their website for professional footage of the robot!)