Increasing Chromatography’s Capabilities
Separating samples into components makes up a crucial step in many of today’s biological projects, and many chromatographic techniques can be used. By applying various forms of chromatography, researchers can pull out increasingly rare molecules from biological samples. To do that, scientists turn to a new generation of chromatographic systems.
To get more sensitivity, Agilent added a new detector to its recent 1200 Infinity Series LC. “These systems come with a Diode Array detector with 10 times higher sensitivity,” says Helmut Schulenberg-Schell, PhD, marketing manager for LC at Agilent. “So you can discover compounds that you could not before, especially in biologics.” In fact, these LC systems can pull out compounds at concentrations of parts per million.
A chromatographic system with such high specificity can play a key role in work with biologics. For pharmaceuticals, very small quantities of a biologic can generate effects. For example, a product including genotoxins—even at miniscule concentrations—can be detrimental.
When stainless-steel components in chromatographic systems come in contact with biological samples, parts tend to corrode and can wear more rapidly. For example, this occurs with the high salt concentrations used in ion-exchange chromatography. To combat this issue, Waters replaced stainless steel with titanium or a nickel-cobalt alloy (NMP35N) in the ACQUITY UPLC H-Class Bio System.
“Many biological molecules tend to interact with stainless steel,” says Jeff Mazzeo, PhD, biopharmaceutical business director at Waters. “So the H-Class Bio System is more bio-friendly.” Capable of performing both LC and ultra performance LC (UPLC) separations, it also uses particles smaller than two microns and works in several modes: reversed phase, ion exchange, size exclusion and hydrophilic interaction.
Some labs want systems that run chromatography at different pressures. For example, the Thermo Scientific Accela 1250 runs high-performance liquid chromatography (HPLC) and ultra high-performance liquid chromatography (UHPLC).
“This type of technology did not exist before, because it is not easy to design an instrument to do both without sacrificing performance,” says Sergio Guazzotti, PhD, global strategic marketing manager, liquid chromatography at Thermo Fisher Scientific. Today’s technology, such as force feedback control in the pumps, allows the creation of such a hybrid instrument that meets performance needs, even in regulated labs.
Getting more from LC, however, depends on more than pressures and pumps. “The technology challenges are not just in the pumps,” says Guazzotti. “With UHPLC, there are other challenges, like detectors that provide maximum sensitivity and sampling rate.” He adds, “The technology is not helpful if you get a one-minute separation and many peaks, but the detector can’t grab the information fast enough and accurately enough.”
To provide a chromatographic system that best fits with a researcher’s workflow, vendors must provide options. For example, Terry Adams, life science unit manager at Shimadzu, says, “When we find customers who know what they want to do, we put a team—including our programmers—in direct contact with the end user to create software-assisted solutions for specific customers.”
Shimadzu also teams up for other reasons. For example, Scott Kuzdzal, PhD, life science business manager at Shimadzu, says, “Clinical diagnostics is a field dominated by the use of ELISA tests, but the immuno-capture portion has not really been applied to liquid chromatography and mass spectrometry as much as it could.” So Shimadzu collaborated with Perfinity Biosciences, which has MALISA (mass-linked immunosorbent assay) technology. As Kuzdzal explains, “We use our hardware to automate the immuno-chromatography on the frontend to prepare samples for mass spectrometry.” The Perfinity Workstation automates several features, including affinity selection, buffer exchange and others. “Rather than fishing for proteins or biomarkers in plasma,” Kuzdzal says, “this provides a targeted approach.”
This technological advance—and the others described here—gives scientists new capabilities. The question now is: How will researchers put this power to work?
This article was published in Bioscience Technology magazine: Vol. 35, No. 2, February, 2011, pp. 10