Among the dyes, why is methylene blue commonly used to measure an active surface area of nanoparticles(especially graphene derivatives)?
I try to find the reason, but I cannot find it.
Could you please tell me that?
MB is used because
- its concentration in solution can be easily measured with a cheap UV-Vis spectrophotometer. However, when strong dilution is required, dilution may lead to relatively large errors in the adsorbed amount ( difference between two large numbers with a small error give a large error in the small difference).
- the isotherm often shows a well defined plateau and can mostly be described with the Langmuir eq (because most data points are lose to the plateau value).
I agree with Luuk, also it should relate to the surface charge of your particles since methylene blue is a cationic dye and can dissociate to positively charged ions so let's say if you have an oxidized (reduced) nanomaterial, the residual oxygen has negative charge, thus, MB+ ions are not repelled and are attracted to the modified sites. Also, from my experience Methylene blue absorbance peak is less impacted by the change in the pH than a common anionic dye like Methyl orange which is also an indicator. Also, compare to other dyes I know it is highly soluble in water, and it's molecule size is smaller and simpler than many other dyes.
- Badges
- Science topic
- Similar topics
- Chemistry
- Nanotechnology
- Nanostructured Materials
- Nanoparticles