Methods and devices are disclosed which can provide an indication of oil quality by measuring a capacitive property of the oil. The methods and/or devices may use a sample acquisition probe comprising a microvolume oil acquisition basin with a capacitive sensing element that is located on the floor of the basin and that is laterally bounded by an oleophilic wetting feature. The methods may involve immersing a sample acquisition probe at least partially into a supply of oil and withdrawing the probe from the supply of oil such that a microvolume oil sample is retained within a microvolume oil acquisition basin of the probe, and measuring a capacitive property of the microvolume oil sample with a capacitive sensing element that is located in the basin.