What is the minimum sample size needed with an ISFET pH probe?
Sample size requirements for ISFET probes.
The volume required depends upon the diameter of the container and the shape of the bottom on the container. The immersion depth of the pH17-SS micro probe is 3mm and the probe diameter is 4.8mm. A volume of 100 μL is about two drops of liquid and this is a normal minimum quantity when using a small diameter tube. If you have less than 100 μL, the best choice would be the PH47-SS NMR Tube Probe designed for use in NMR tubes. This probe can test about 50 μl when used with a standard 5mm diameter NMR tube.