Square waves happen in the ocean when waves in different directions cross each other. They are beautiful but dangerous for swimmers. Square wave voltammetry is similar but I think definitely less dangerous.
I will use an incomprehensible introductory sentence and then deconstruct this in order to explain.:
Square wave voltammetry (SWV) combines linear sweep voltammetry (LSV) with a pulse profile.
A picture here might be useful.
The differential pulse in the diagram above is linear sweep and the staircase is the pulse. The combination of these two is the square wave pulse diagramed on the bottom. This is plotted versus the staircase to provide a signal as follows.
We integrate the area under this peak to determine the signal.
Key advantages of square wave applications are:
- Speed of analysis (seconds per read)
- Chip to chip consistency
- Simple to interpret
In the next blog, I will discuss in more detail how we work with square wave voltammetry with aptamers.
In the meantime, consider this blog as a safety announcement, stay out of the water if you see square waves!!!