Bubble and liquid junction serious pollution situation, you can first use the following solvent cleaning, then deionized water to solvent, the activation electrodes immersed in soaking solution.

Pollutant cleaning agent

Inorganic metal oxides are lower than 1mol/L dilute acid

Dilute detergent (weak acid) of organic oils and fats

Resin polymer materials: dilute alcohol, acetone, ether

Protein blood cell precipitate acid enzyme solution

Dilute bleach and hydrogen peroxide