Chromatography Forum

Hi,

One of my customers wants to study the oxidation products of his compound. He is planning to prepare samples containing his compound along with strong oxiders such as H2O2, permangate, and pyridimium dichromate. Will these samples hurt our instrument? We are using a Prevail C18 column for these samples. What will these strong oxiders do to our column? Is there any suggestions of precautions that we should take first? Any advice is greatly appreciated.

Thanks,

Karen Jones

I've never tried injecting it onto an HPLC column, but having used permanganate for various other purposes, I can say that neutral or alkaline permanganate will leave deposits of MnO2 everywhere. If it won't ruin the experiment, you can titrate the excess oxidizer with a mild reducing agent such as oxalic acid, sulfite, thiosulfate, ascorbic acid, formic acid, etc.

For force degradation study normally we used hydrogen peroxide as oxidising agent and we inject sample. We don't find any column or system problem. I don't know about permagenate or pyridimium dichromate.

Narendra

One oxidizer I have injected on column is neutral periodate. I noticed no ill effects. It is handy for oxidizing thioethers to sulfoxides; permanganate or peroxide will go to sulfones.

In most cases, the amount injected is so small that it is very unlikely that you would damage the column. In addition, these compounds do not stick to the C18 and flush right through. Thirdly, people in the pharmaceutical industry do compound degradation via oxidation all the time, and analyze the products afterwards via HPLC.

In summary, unless the conditions are extreme, I would not worry about damaging the column.