By Anonymous on Thursday, December 12, 2002 - 09:02 am:
Hi,
I need to do some protein analysis using LC/MS/MS.
In order to gain good sensitivity, I need a capillary HPLC.
Does anyone has some suggestions on which company's capillary HPLC is better?
I think the flow stability is the most important, and quality of the pump is also very important.
By Gerhard Kratz on Friday, December 13, 2002 - 06:19 am:
Hi Anon, we have some information available on capillary SEC of proteins. SEC material TSKgel SuperSW2000 4µm was packed into a 300µm x 300mm capillary. Please e-mail if interessted to g.kratz@tosohbiosep.de and I will forward to you details about instrumentation and application. Gerhard
By Anonymous on Monday, December 16, 2002 - 03:34 am:
Can anyone tell me why you (apparently) get better sensitivity in capillary HPLC ES-MS than in packed column HPLC ES-MS? Let's assume that the volume of the sample is not an important consideration ie we can scale up the volume injected on to the packed column. There are a number of reasons why (even in this case) the sensitivity might be better, but I'm not sure which are the most important.
By Anonymous on Wednesday, December 18, 2002 - 05:50 am:
Electrospray is a flow sensitive ionisation. Lower flow = better ionization. Electrospray is a concentration based (not amount) technique. In cap LC peaks elute in a smaller volume (ie higher concentration for a given amount), therfore higher sensitivity. Together these 2 effects give an overall much higher sensitivity when using cap-lc-esi.
By Anonymous on Wednesday, December 18, 2002 - 01:54 pm:
You can check out the Rheos 2000 pump with the CPS module for low flow. Contact LEAP Technologies, www.leaptec.com for more information.