ESA Analytical has introduced a new methodology that is capable of quantifying the central level of a drug while simultaneously measuring its effect on central metabolism
Until recently the central level of a drug and its effect on neurotransmitter metabolism was normally determined in brain tissue homogenates.
However this approach suffers from a number of disadvantages including the inability to accurately examine tissue distribution, the loss of analyte compartmentalisation, and the need for a large number of test animals.
The new technique introduced by ESA uses microdialysis perfusion to permit direct sampling of the brain's extracellular fluid, within the blood-brain barrier, in freely moving animals.
Based upon an HPLC with coulometric array detection method, applications data is presented using the anti-hypertensive drug H (1-hydrazinophthalazine) as an example of how a drug passes through the blood-brain barrier and can be measured quickly and effectively post infusion.
The data presented clearly demonstrates the potential of coupling in-vivo microdialysis to HPLC with coulometric array detection to enable simultaneous measurement of a drug's level and its effects on central monoamine metabolism.
Using ESA's CoulArray electrochemical detector for HPLC provides the superior sensitivity and selectivity required for measuring low picogram levels of centrally acting drugs and their metabolites in brain extracellular fluid.