By Anonymous on Friday, August 9, 2002 - 12:55 pm:
I am trying to develop a method to detect a drug in plasma by direct injection. Can anyone recommend a restricted assess medium column or size exclusion column that they have tried.
By Benjamin on Friday, August 9, 2002 - 01:01 pm:
Dear Anonymus;
I recommend you get in touch with Melvin Cabbey at Diazem Corp. (989-832-3612). They specialize in RAM columns and SPE cartridges. They can also provide a few application notes describing problems such as the ones you mention.
Good Luck;
Benjamin
By Anonymous on Saturday, August 10, 2002 - 10:57 am:
What detector do you use?
By Anonymous on Monday, August 12, 2002 - 09:04 am:
Benjamin, thanks for the tip.
Anon, I am using an LC-MS detector.
By Uwe Neue on Monday, August 12, 2002 - 08:40 pm:
We have been using short Oasis columns for exactly this kind of application, with cycle times as low as one minute, if you are pushing the envelope. Two minute cycle times are achievable without headaches. You can find examples of reversed-phase applications as well as mixed-mode ion-exchange applications on the Waters website or in Rapid Comm. Mass. Spec. 2001, 15, 1075-1083 and 2002, 16, 805-813.
By Anonymous on Wednesday, August 14, 2002 - 04:48 am:
One that has been around for years is the BioTrap 500. This is a very short (2cm) extraction column capable of handling serum or plasma with ease. It is made over in Europe but is available through many companies here in the USA. Search BioTrap on the WWW or simply visit their web-site at www.chromtech.se/biotrap.