ECD Innovations

Rapid (< Four Minutes) Determination of Dopamine and Serotonin
In-vivo microdialysis methods today are pushing toward greater temporal and spatial resolution. This means smaller sample volumes, shorter collection times, and the use of smaller probes for better placement in discrete brain regions. This often results in a large number of low-volume, dilute perfusate samples requiring both high sensitivity and rapid chromatography. Two approaches have evolved to address these needs: rapid off-line analysis to support very short collection times, or a balancing of collection and chromatographic times for direct on-line analysis.

Now, the neuroscientists at ESA have developed a more-effective solution for rapid analysis of these two key neurotransmitters using a low-volume amperometric-detection technique optimized for both speed and sensitivity and ESA's incredibly reliable HPLC-ECD system. It can even be used to simultaneously measure pre-frontal cortical levels of dopamine (DA) and serotonin (5HT) under basal and amphetamine-stimulated conditions – in under four minutes of analysis time! This system, which can be used either on- or off-line via a switching valve, is a must for researchers studying the regional interplay of monoamine neurotransmitters during pharmacological manipulation or behavior. It can also be used for the simultaneous monoamines method reviewed in Spring 07 edition of The Femtogram.

For more information about rapid DA and 5HT analysis or other high-performance ESA applications, please contact your local ESA representative or e-mail your request to info@esainc.com.

Microdialysis samples obtained from a 3 mm concentric microdialysis probe placed in the prefrontal cortex of an awake rat, before and after amphetamine ( 2mg/kg i.p.) stimulation. The ESA system resolved DA and 5HT in under four minutes, showed excellent linearity, and extreme sensitivity (~50 fg on column).