Chromatography Forum

Hi,

I'm going to be starting to develop a method to analyze phenoxyethanol in personal care products, along with methyl and propylparaben and methylchloroisothiazolinone/methylisothiazolinone. So far I have good background/starting info for the parabens and MCI/MI. Does anyone have any suggested methods for phenoxyethanol? Although I haven't started just yet, I would like to be able to combine all the above mentioned chemicals into one method. It looks like the parabens and MCI/MI could possibly be combined in one method, but it would be helpful to add the phenoxyethanol in as well. If not, does anyone have any suggestions as to starting conditions?

Thanks

Red - you're going to find that on some aged or "experienced" RP-18 columns phenoxyethanol and methyl paraben may coelute, so be sure to use a new column (we also have used a specialty column for this). I've also done a zillion methylisothiazolinones and the chloromethylisothiazolinone but never tried do combine with the phenoxyethanol parabens, but I'd say go for it, it's worth a try. You'll need to start at a high aqueous concentration for the methylisothiazolinone, and program up the organic.

Thanks for the info. I've been gathering information for system conditions, so I'm about ready to try things out. The only thing I was curious about was sample size. Any suggestions as to the concentration of the samples? Thanks!!