Courtesy of Waters
Long the method of choice for fast, accurate protein purification, HPLC has been revamped in recent months. Two companies, Agilent Technologies in Palo Alto, Calif., and Waters in Milford, Mass., released new high-performance liquid chromatography systems designed specifically for the microscale sample requirements of mass spectrometry-based proteomics. Though they adopt different approaches, both systems have been hailed by developers and users alike as harbingers of liquid chromatography's next wave.
SMALLER PARTICLES, HIGHER EFFICIENCY
Water's
Central to UPLC is the 1.7 μm, ethane-bridged, hybrid silica-polymer particle used as...
HPLC-ON-A-CHIP
Proteomics researchers working with small sample sizes have largely turned to capillary nano-LC technologies, which are based on fused silica capilary tubes linked by fittings and connections. These fittings have relatively high dead volumes and can get clogged easily. Enter Agilent's
Courtesy of Agilent
Eliminating LC components also aids troubleshooting. "Doing nanoflow can be very tricky because of how you have to put things together. And you're going at a very low flow rate, so it's very hard to detect leaks. It's hard to troubleshoot if anything goes wrong," says beta-user Karen Jonscher, University of Colorado, Boulder. Like other nanoflow systems, the HPLC-Chip can be tricky to use, Jonscher cautions. "You have to have everything working right all at the same time for it to work. Things that you could fudge in a normal slow source and that would still work, you can't fudge in this," she says, noting that her version is a pre-production system and that Agilent has since redesigned the chip. "I think it'll be the easiest system for somebody who's not familiar with nanoflow to get up and going with," she adds.
Pierre Thibault of the University of Montreal, who has used the system for the past four months, says the system's compatibility with other MS systems is another concern. It is currently configured only for Agilent's MS instruments, but Christina Maehr, Agilent press-relations manager, says the company has long-term plans to make the chip platform more broadly compatible.
- Aileen Constans