Back to Photo-Acid Generation!

As a result of the problems associated with working with my photo-base generator and the lack of options in choosing a new one (photo-base generating compounds are not very heavily studied), I decided to return to photo-acid generators, a type of compounds I worked with last Fall. The most promising was an azobenzene compound that released acid via a photo-isomerization process. It also matched very well with my nanoparticle polymer, PPE, to undergo FRET (Fluorescence Resonance Energy Transfer), the phenomenon that I am studying.

As I said in my abstract, there were some problems back in the Fall associated with not knowing exactly how the acid was reacting with the nanoparticles. Fluorimeter readings gave very clear indication of acid-release, but pH readings did not corroborate. We assumed that the negatively-charged nanoparticles were absorbing the positively-charged acidic protons. To mitigate that effect, we attempted to coat the nanoparticles with another, positively-charged polymer, but we couldn’t find a good coat percentage that would not cause aggregation. As a result of these compounding issues, we decided to change to PBGs. But now we’re back!

With a new instrument coming near the beginning of classes that will give us more information about the nanoparticles, it makes sense to return to the azobenzene and set the foundation to continue working with it.