Im working with a S. typhimurium strain.

Until now when i wanted to have a look at the amount of Lipid A present in the cells, i did silverstainings with proteinaseK treated whole cell samples. This works perfectly fine and one can compare different levels of Lipid A between samples/lanes.

It would be great, to have an easy and fast method for a more quantitative analysis.

I was thinking about staining the LPS/Lipid A with NileRed or BODYPI and then measure the fluorescence by FCM. Has anyone any experiance with that?

I also found that Polymyxin B binds Lipid A selectively. But i can only find biotinylated or HRP-conugates. Does anyone might know of a source of fluorescently labeled Polymyxin B?

Thanks a lot!