By James on Friday, June 4, 2004 - 01:19 am:

Hi. We have a waters 2695 controlled LC/MS . We have been injecting samples which have lots of "biological rubbish" in them - even after MeCN extraction, which of course is no good for our mass spec - cleaning is becoming a nightmare. We think a flow switch would be a good idea as the rubbish generally goes straight through the column in the first couple of minutes before our drugs elute.

I know that the 2695 can send event-switch signals at specific times, so I am wondering if anyone knows of a good (reasonably priced) flow switcher out therewhich we can hook up to the 2695. This way our mass spec would stay clean for much longer :)

Thanks.

James

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By Anonymous on Friday, June 4, 2004 - 05:31 am:

James,
Might I suggest you talk with Valco, they have a nice variety of electropneumatic and electrically switched valves that would suit your purpose. I have used some before to make a homemade fraction collection system. The valves seemed very relibale and easy to use.
website = www.vici.com
P.S. Their folks are very helpful also.

Regards,
Mark

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By Anonymous on Saturday, June 5, 2004 - 10:11 am:

also, check out:

http://www.rheodyne.com/products/fluidi ... /index.asp