Porous graphitic carbon columns achieve high speed, high efficiency HPLC separations at ultra-high temperatures
Thermo Electron introduces a new range of HPLC applications at ultra-high temperatures using Hypercarb (porous graphitic carbon) columns.
The use of ultra-high temperatures (up to 200C) in reversed phase liquid chromatography (RP-HPLC) has several advantages: higher peak capacity - at higher temperatures solvent viscosity is reduced, which enhances the mass-transfer between mobile and stationary phases resulting in higher efficiencies, providing sharper peaks and increased peak capacity; higher sensitivity - because more efficient peaks and shaper peaks are obtained at high temperatures, there is an improvement in peak height, therefore better signal-to-noise ratio; and higher speed - at high temperature backpressure is reduced thus higher flow rates can be utilised for fast separations without compromising efficiency.
Columns packed with modified silicas, which are generally used in RP-HPLC, should not be used above 60 to 80C.
At these extreme temperatures, hydrolysis of the organosilane bond or dissolution of the silica may occur.
Hypercarb media is the ideal stationary phase for high temperature HPLC, since it is not affected by physical or chemical degradation at high temperature regardless of mobile phase used.
Hypercarb is 100% carbon, which is chemically very stable and robust, and therefore can be routinely used up to 200C under either isothermal or temperature gradient conditions.
Thermo's new applications illustrate the use of temperature as a method development tool for the chromatographer in the environmental, pharmaceutical and other analytical laboratories.
They show how high temperatures or temperature gradients can be utilised to achieve fast, high efficiency separations.
The use of a mobile phase of pure water, combined with temperature gradients, is also demonstrated for the separation of very polar analytes on Hypercarb columns.
Hypercarb columns are available packed with 3, 5 and 7um particle sizes and in a range of hardware designs, internal diameters and lengths.
