Date: Tue, 21 Jan 1997 11:46:07 -0800 (PST)
From: Lowell Ericsson <ericsson@u.washington.edu>
Subject: HPLC-P32 Detectors
To: Recipients of ABRF List <abrf@aecom.yu.edu>
Flow thru detectors vs. Static liquid scintillation system
1. Counting time. In a flow thru detector one can count only as long as
the peak is passing the detector. The sharper the peak, the less counting
time available. The faster the flow, the less counting time available.
With a static liquid scintillation system one can leave the sample in the
detector chamber for any length of time and thus improve the counting
precision a real advantage for samples with very low counts.
2. Scintillation cocktails and their photo detectors used in the static
liquid scintillation systems are very efficient compared to detectors in
the flow thru systems.
3. Flow thru systems are nondestructive. With static liquid
scintillation systems one must sacrifice part of the sample unless the
less sensitive Chernkoff counting system is used.
4. Flow thru systems require less sample handling.
Conclusion:
Several years ago we evaluated two flow thru systems and decided to stay
with our old fashion liquid scintillation counter. If the situation has
changed, I would appreciate seeing some data.
-Lowell H. Ericsson, Dept. of Biochemistry, U. of Washington, Seattle, WA