Application Notes
Pharmaceutical Stimulants by HPLC/ELSD
Three pharmaceutical stimulants, theophylline, caffeine and ethamivan were separated by reversed phase HPLC/ELSD.
Pharmaceutical Stimulants, Alltech Application Note 0049LE, July 7, 2000.
Three pharmaceutical stimulants, theophylline, caffeine and ethamivan were separated by reversed phase HPLC/ELSD. A Low Temperature Adaptor was used to increase sensitivity and maintain stable baselines because a large portion of the mobile phase is aqueous and contains acetic acid.
A mixture of the three stimulants was separated isocratically in around 5 minutes by reversed phase HPLC on a Platinum EPS C18, 5µm, 250 x 4.6mm column (Part No. 32214) using methanol/acetonitrile/acetic acid. The stimulants were detected by evaporative light scattering using an Alltech 500 ELSD (Evaporative Light Scattering Detector).
In ELSD, the mobile phase is first evaporated. Solid particles remaining from the sample are then carried in the form of a mist into a cell where they are detected by a laser.
Key Analyte(s)
caffeineCaffeine, a coffee extract acts as a stimulant on the central nervous system and long term use can lead to dependency. It is most often meaasured using HPLC, GC/FID and GC/MS.
ethamivan
theophylline
Equipment
Alltech Platinum ColumnsThe Alltech Platinum Columns are designed to separate mixtures that a strongly hydrophobic phase cannot. They are silica based (100Å) and are available in Standard Platinum for neutral and moderately polar compounds and Platinum EPS (Extended Polar Selec
Technique
HPLCHigh Performance Liquid Chromatography (HPLC)is a technique for separating components in a sample on the basis of interactions between the component, a liquid mobile phase and a solid stationary phase.
Source
Alltech Associates, Inc.Alltech Associates, Inc., one of the leading suppliers of HPLC columns, manufactures and distributes HPLC, GC and IC columns, accessories and consumables and maintains a large searchable database of application notes and chromatograms on its website.
