The utility model belongs to the technical field of PH test pens, and particularly discloses a cotton-sealed pH
test probe which comprises a shell and a
glass electrode, the
glass electrode is sleeved with foamed plastic, the foamed plastic and the
glass electrode are jointly sleeved with the shell, and a test head of the glass
electrode and the foamed plastic are both exposed out of a test end face of the shell. A
reference space defined by the shell, the glass
electrode and the foam is internally provided with a reference element and is filled with a reference
electrolyte, one end of the reference element is immersed in the reference
electrolyte, and the other end of the reference element extends out of the
reference space. The space between the glass
electrode and the shell is sealed through the foam, the
reference space defined by the shell, the glass electrode and the foam is filled with the reference
electrolyte, the foam serves as an electrolyte carrier, the reference electrolyte is communicated with liquid to be detected through the foam, the reference electrolyte is improved, and the detection accuracy is improved. Therefore, the
conductivity of the reference electrolyte is effectively improved, the pH value stability of a reference
system is enhanced, and the service life is prolonged.