HPLC Systems: Powerful New Systems, and a Renaissance for Old Systems

Manufacturers of high-performance liquid chromatography (HPLC) systems continue to innovate, while simultaneously providing upgrade paths for older instruments.

Modular HPLC systems provide maximum flexibility and upgradability compared with “one box” integrated chromatographs. By switching modules, users can access the latest technology while reducing downtime during repair or servicing.

On the other hand, integrated systems are more affordable. Agilent’s 1220 Infinity, which is modular, costs about 25 percent less than a comparably equipped 1260 model, yet the two use identical subcomponents. According to Dr. Michael Frank, marketing manager for analytical HPLC at Agilent (Waldbronn, Germany), integrated systems are less expensive because they use only one power supply, one set of communication electronics, and one cover.

Since HPLCs are long-lived instruments, upwards and downwards compatibility is a major concern. Compatibility also provides a relatively straightforward upgrade path, provided components are replaceable and the manufacturer has embraced open architecture. For example, older instruments may access quick-change valve technology, which facilitates plumbing tasks.

Method transfer has been the bane of chromatographers for years, and a major roadblock in the adoption of novel HPLC technology. Many established methods specify not only solvents and gradients, but columns. As a result, many labs feel tied to old technology, however, users tend to exaggerate the cost and time involved in revalidating methods.

Regardless, a solution may be on the way. Agilent’s Intelligent System Emulation Technology (ISET), available on its top-end HPLC systems, creates a software environment in which a chromatography run on, say, an Agilent 1290, can be made to emulate any older HPLC system and, according to Agilent, deliver “exactly the same results.” ISET is pure software and does not require hardware modifications.

In a company announcement at Pittcon, Agilent senior marketing director Stefan Schuette described ISET as “…the beginning of a new era” in which users “…will be free to develop, validate, and execute all methods on one single instrument… and to emulate those HPLC and UHPLC instruments to which a method should be transferred or on which it has been developed.”

Dr. Frank believes legal and regulatory authorities will accept these “virtual” chromatography runs. “I’ve spoken with experts in regulated industries, and they don’t think it will be an issue.” The advent of smallparticle- size columns has made HPLC vendors rethink system design to exploit the new columns’ resolving power, says Alessandro Baldi, Ph.D., senior business director at PerkinElmer (Waltham, MA).

That means positioning the injector and gradient mix almost on-column, and the detector immediately outside at the back end. Proximity reduces volumes between modules and therefore helps eliminate dispersion while improving signal to noise and resolution. Perhaps the most exciting development affecting HPLC systems over the past several years has been the introduction of superficially porous silica particles.

The novel particles promise performance approximating—some vendors say exceeding—that of UHPLC but at normal back pressures, meaning labs can keep using their old HPLC equipment and achieve results normally associated with very high back pressures.

Recently Released HPLC Systems

SecurityGuard ULTRA UHPLC Column Protection System

Suits almost any manufacturer’s UHPLC, sub-2-micron or core-shell columns including the Phenomenex Kinetex® products
Protects against the damaging effects of chemical contaminants and microparticulates introduced by the sample, mobile phase or system
Pressure-rated up to 20,000 psi (1,378 bar)

Phenomenex
www.phenomenex.com

Low-Pressure Gradient Unit for Nexera UHPLC
LPGE

130 MPa high-pressure resistant gradient system
Allows users to switch automatically between four mobile phases
Features excellent retention time repeatability
Automatic method switching assured with automatic purging and baseline check functions

Shimadzu
www.ssi.shimadzu.com

EASY-nLC 1000

Facilitates dedicated separation of biomolecules, such as proteins and peptides, at ultra-high pressures
Easy to use and can seamlessly integrate with the complete range of Thermo Scientific mass spectrometry (MS) systems for instant, trouble-free operation
Significantly shortens analytical cycles

Thermo Fisher Scientific
www.thermo.com

ACQUITY UPLC® I-Class System

Reduced system volume decreases dispersion
Delivers reproducibly higher resolution and superior peak capacity
Low dispersion footprint allows users to reduce their separation cycle times
Design and materials dramatically reduce sample carryover effects

Waters
www.waters.com