Hi Marcus,

I've spent a lot of time trying out different sealing solutions for HPLC samples in the 96-well format. It sounds like all you're worried about is the adhesive, in which case these foils might work for you:

http://www.excelscientific.com/ezpierce_content.html#zonefree

They only have adhesive in a ring around the well, so there shouldn't be any contamination of your samples or gumming up of your injectior needle.

We are using samples that are dissolved in Methanol and these wouldn't work, as even 'solvent resistant' foils would peel off quickly and samples would evaporate. What I've found to work by far the best for us is the tube-rack system by Micronic:

http://micronic.com/product/loborack-96

We use the 0.5ml tubes that come in a 96-well format, which have about the same format as a 96-well plate. They go together with the Micronic TPE-capmat that provides a perfect solvent resistant seal (we use them to store our samples, no evaporation after months) but can be repeatedly pierced by any autosampler needle, without damage to the needle or loss of seal. The tube/mat sytem is a little more pricy than the adhesive foil but mats and racks can be re-used.

Hope this helps,

Tobias

Hi Tobias,

Thank you for the recommendations.  Dissapointingly since posting this question I actually ordered EZ-pierce and X-pierce films to try them out but my samples are 66% MeOH so I'm guessing I may have to try a mat set-up.  I only require that the samples are sealed for a maximum of 24 hr (the time it takes to reach the last sample on a LCMS run) so in your experience when you say 'peel off quickly' do you mean hours or days?

Thanks again

Marcus

Hi Marcus,

My samples are in 100% MeOH, and most sealing films that I've tried would come off within a couple of minutes. I've also tried the regular adhesive foils that seem to be working for you, and those came off within a couple of hours. So maybe the difference in solvent is enough that you won't have that problem.

Good luck,

Tobias

Better late than never.........for anyone else reading this question......I have used ZoneFree films from Alpha Laboratories for a while now and had no problems with these detaching regardless of solvent used.  Just ensure the top of the plate is dry when applying the film and all should be fine.

Dear Marcus!

Could please specify which product was the best?

Thanks,

Regards,

Roland

Hi Roland,

The Zonefree Sealing films are available from Alpha Laboratories (cat # ZAF-PE-50 ) or from sigma (cat # Z721646). I've used these now for 3-4 years without issue BUT only with MeOH or MeCN so I've no idea how they would react with stronger/different solvents.

Hi Marcus,

Many thanks,

Regards,

Roland