Probe shanks should be rinsed with deionized water as soon after removing from brain/solution as possible, i.e. before saline solution has had a chance to dry and deposit crystals on the recording sites. The crystals will impair recording quality, though any effect of these for the next recording should be transient, as the crystals will re-dissolve. After rinsing, soaking in deionized water is optimal.
The probe shank can also be soaked in a tergazyme solution to clean biological material. After soaking in tergazyme, it should be soaked and rinsed with deionized water.
It is recommended to cover the "backside components" of the probe with epoxy, particularly if there is any chance of them coming into contact with saline. The formation of crystals on these components, or any corrosion, could break the probe.