It is common to measure the peak absorbance of the plasmonic nanoparticles in solution and then get the following:
- Molarity (moles/liter)
- Number of particles per ml
- Weight concentration (ug/ml)
I wrote a small python function to extract these parameters. The following inputs are needed for the function
- d_nm : diameter of the particle in nanoparticle
- od : peak OD measured from the absorbance plot
- path_length_cm : cuvette length in centimeter
- density_g_per_cm3 : for gold it is 19.28, for silver it is 10.49
- molar_Extinction_perM_percm : Molar extinction coefficient extracted from here.
- This can extracted from measuring absorbance at different concentrations and then fitting a linear line. the slope will be molar extinction coefficient
Here is the code.