Thermo Fisher Scientific has issued an application note to demonstrate ultra-high-performance liquid chromatography (UHPLC) capabilities for the separation of drugs of abuse in complex drug mixtures.
Illustrated in the application note is the advanced ability of the Thermo Scientific Accela UHPLC system to perform efficient, improved-resolution separations using a quaternary UHP mixing pump.
The application note, entitled 'A Comparison of Binary and Ternary Gradients Using Stage 1 Illicit Drugs', is available for download.
When using an HPLC method to separate a complex drug mixture, a simple binary solvent gradient can often fail to provide the sufficient resolution of all analytes.
In order to improve the resolution, the separation factor has to be manipulated by using a third solvent.
However, this approach is not possible with typical high-pressure binary solvent mixing equipment.
The Accela UHPLC system is claimed to overcome this limitation, featuring a quaternary mixing pump that facilitates the use of up to four solvents for method development, system flushing and eluent preparation.
The changing of solvents, buffers and pH values is said to be quick and easy, simplifying the method development process.
The application note describes an effective method for the separation of drugs using the Accela UHPLC in conjunction with the Thermo Scientific MSQ Plus Mass Detector: a fast-scanning single quadrupole mass spectrometer (MS).
A mixture of 14 drugs is separated and baseline resolved by UHPLC/MS within eight minutes on a Thermo Scientific Hypersil Gold PFP column using a ternary solvent gradient, which is not possible using a conventional binary solvent gradient.
Methanol was found to provide improved resolution for most of the drug compounds compared with other eluents.
