In 2004, a new category of LC technology was introduced that has changed separation science forever.
High performance liquid chromatography (HPLC) is a proven technique predominantly used in most laboratories. The primary driver for the growth of this technique has been the evolution of the packing material used to effect the separation. The underlying principles of this evolution are governed by the Van Deemter equation, which describes the relationship between linear velocity (flow area) and plate height (HETP or column efficiency).
According to the Van Deemter equation, as the particle size decreases to less than 2.5µm, not only is there a significant gain in efficiency, but the efficiency does not diminish at increased flow rates. By using smaller particles, speed and peak capacity can be extended to new limits termed Ultra Performance Liquid Chromatography (UPLC).
Scientists are now realising they can do and see with UPLC what they could not do and see with HPLC. The benefits are real and compelling, and the technology is making an impact in more laboratories. A typical comment is: ‘UPLC revealed peaks in the samples that we simply did not know were there by conventional HPLC.’
Holistic design
Waters ACQUITY Ultra Performance LC system is designed to take full advantage of the potential of novel sub 2 micron particles to give scientists chromatographic run times that are up to nine times shorter than today’s fastest HPLC systems, up to two times better peak capacity or resolution, three times better routine sensitivity, and, generally, more information from a single run than anything today’s HPLC systems can provide.
What sets the ACQUITY System apart from other systems is a new, patented 1.7 micron pressure-tolerant, reversed phase hybrid particle chemistry matched with instrumentation. The hardware and software promises scientists significant benefits over today’s HPLC systems equipped with standard 5 micron particle chemistries.
Designing a system for sub-two micron particle operation was a challenge and drove Waters to look at all aspects of system design in a holistic manner. UPLC is sub 2 micron particles and high pressures, and all the components of the chromatographic system had to be designed to fit with the requirements of UPLC separations. The challenge called for new thinking in many areas; new designs for solvent management, which when combined with new software algorithms are capable of a constant linear flow at elevated pressures; high-speed detectors capable of capturing fast separations; and faster injection cycles to keep up with the instrument’s higher throughput – all while optimising the flow path of the system to reduce dispersion, and adding new communications technology that tracks and reports column usage.
The result is a system that accentuates and combines chromatographic speed, sensitivity and resolution.
This year, Waters introduced four new chemistries – a C18, C8, phenyl and a Shield RP18 – as well as an evaporative light scattering detector to further expand applications for UPLC.
Just the beginning
Waters is committed to working with scientists to address their daily challenges and use this understanding to direct its technology development efforts. Waters remains the only company that can offer a comprehensive set of technologies for UPLC – instrumentation, informatics, and chemistries – designed to work together as a total system with one goal in mind: to get scientists quality information, faster.
UPLC is here to stay and it will continue to have a lasting impact on laboratories worldwide. End
Ultra Performance LC, ACQUITY UPLC and ACQUITY UltraPerformance LC are trademarks of Waters Corporation.