Different techniques are used to clean SPE, depending on SPE surface type and level of contamination. The cleaning may be further divided into three types:
- Chemical cleaning methods (using solvents).
- Piranha solution (owing to strong aggression, not preferred).
- Aqua regia
- Thermal cleaning method:
- UV ozone cleaning
- Electrochemical cleaning methods (using cyclic voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) technique)
- KOH sweep method.
- Potential cycling using H2SO4 or HCl.
- CV sweeping using potassium ferricyanide.
- Taking negative sweeping potential (using CV technique).
[Reference: 10.3390/pr10040723]