Yesterday, I had a bit of a mishap with an Arduino and a Pololu DRV8825. Grapefruit juice was (inadvertently) spilled on both. Luckily, neither was powered when this happened, and I was able to towel off most of the juice. They have been left to dry overnight, however there is some stickiness here and there.
What would be the best way to remove the residual juice/stickiness? Would soaking a cotton bud in isopropyl rubbing alcohol and then swabing the affected areas be a good approach? Are there any sensitive components on either the Arduino or the DRV8825 that would be damaged by such alcohol?
If only you have washed the boards with IPA when the accident happened.
You may be lucky and the acid in the grapefruit juice has not damaged the copper tracks.
Be careful rubbing the circuit boards as you may rub off small SMD components
As it was not running at the time, you have probably not destroyed it unless the tracks are corroded.
What should have been done is wash it off with isopropyl alcohol. If this is not available, use water but it needs to be dried thoroughly. This can be done by flicking as much off as possible and leaving in the sun. Or GENTLY heating with a hair drier held about 300mm away.
It is probably not too late and you have nothing to lose.
Isopropyl alcohol should clean it well. I have 99% anhydrous Isopropyl alcohol that I use for cleaning flux off boards that we've hand soldered. Dries very quick thru evaporation as there is very little water in it.
I doubt grape juice will damage tracks that are covered under soldermask - you ever try getting soldermask off to solder to the trace underneath? Other traces will be covered with solder where the trace/pad connects to a component, grape juice will not corrode that with.
Use a stiff paint brush and apply the alcohol liberally, let it dry thoroughly. I wouldn't submerse anything.