Monoamines and metabolites

One injection, two chromatograms. Analysis of mouse prefrontal cortex microdialysate using the ALEXYS Monoamines analyzer.

ALEXYS Monoamines Analyzer

• One injection, 2 chromatograms
• Multi-component analysis
• More data with less rodents

Antec has developed an integrated system solution for the analysis of monoamines and metabolites in microdialysates and tissue homogenates. The method is optimised for small sample volumes (3 or 5 μL injection) with a detection limit below 50 pmol/L for the biogenic amines.

By means of a dual loop 10-port valve a single injection is loaded on two LC-flow paths simultaneously. This concept was applied to the analysis of noradrenaline (NA), dopamine (DA), serotonin (5-HT) and their metabolites. Chromatography is optimized to retain the fast eluting NA, as well as speedy analysis of the strongly retained 5-HT and acidic metabolites.

Optimizing ECD parameters in each flow path resulted in best selectivity and sensitivity for the different components. Especially for the volatile 5-HT speeding up the analysis time was necessary to obtain acceptable detection limits.
Filling two sample loops during one injection event minimizes sample use and running two analyses in parallel results in an increased sample throughput.

System configuration

For the Monoamines analyzer we selected the VT03 electrochemical cell. This cell not only has an excellent reproducibility but also the best possible detection sensitivity. We routinely inject 2-8 µL with a maximum sample use of less than 10 µL, therefore we selected a micro version of our AS 110 autosampler. We use a 1 (or 2) mm ID column at 50 (or 250) µL/min.

The ALEXYS system comprises the following parts:

• AS 110 autosampler, cool, micro
• LC 110S HPLC pump
• OR 110 organiser rack
• Clarity data acquisition software
• DECADE II electrochemical detector, DCC
• VT cell with GC WE, salt bridge

 For more details see our product catalogue.

Notes

• 213_025_03 - Monoamines analysis in microdialysates
• 220_011_05 - Micro volume injections

Posters

• 221_025_01 - Recent Developments in Neurotransmitter Analysis