Chromatography Forum

I happen to goto a chemistry lab. Notice that they will rinse all the washed glassware again with acetone after it is thoroughly wash with detergent before leaving it to dry. Is this a standard practice. What is the purpose of this?


My question is: is there any standard dos and donts for glassware that we need to observed if the application is for HPLC work especially for the bottles used to contain the mobile phase.

In general, why do we use glass bottles to prepare our stock or standards but other times, we can use plastic tubes like eppendorf or falcon tube.

Appreciate if someone can comments.

Thanks a lot.

Some of this has been discussed before, so I am just relating some experience. First of all, it all depends on what you handle. Since my work with fatty acids, and because of some possible adverse effects in HPLC (see for instance the chain on the SW 3000 column) I avoid using detergents alltogether. Also acetone is banned on anything that will hold mobile phase, as I work with UV detection a lot (using mobile phase and/or its components for washing, instead, might be prudent, sometimes con H2SO4 or aqu. NH3 has been necessary, followed by mobile phase, etc.). I am affraid to use plastic containers to store mobile phase or related solutions (especially low polar organics), because plastisizers, monomers.. might be solvated, or diffusion through the plastic may occur. I have used polypropylene micro vials extensively for aqueous biological samples (sometimes even with various amounts of alcohols or ACN present), as I am not that much affraid to inject possible relatively low polarity "dirt". Polycarbonate is dissolved by acetone, ACN and alcohols seem to attack it more slowly? (Not so sure about that, water doesn´t seem to do anything to this material, we use polycarb. test tubes only for checking the pH of aqu. buffers, to prevent scratching of the electrode).

In my experience, many 'seasoned' chemists will rinse out glassware with the major solvent of whatever they are doing before use, on the basis that any crud in the glassware that might get into their experiment will get washed away.

For HPLC I routinely rinse solvent bottles with ultrapure water and leave them upended to drain before I use them, it's not a critisism of the people who wash glassware, just a 'belt and braces' approach.

Paul.

Dear all,

Thanks for sharing with me about your experience. Really appreciate it. Does anyone happen to know of any useful websites that I can read up more about this area?

HW Mueller: you mention that some of this has been discussed before, is it in this forum?

Many thanks again.

Yes, in this forum, but it might be difficult to find, maybe some of it under mobile phase, microbes, bacteria....