The 4,500-odd attendees at this year’s meeting of the American Society for Mass Spectrometry know how to take advantage of a good thing. For the $200 price of admission for ASMS members, attendees immerse themselves in the intricacies of mass spectrometry — from protein and polymer analysis, explosives and bioweapons detection, even fundamentals such as the study of zwitterions — as well as indulge in corporate generosity in the form of Beck’s beer and fancy hors d’oeuvres.
Not to mention the chance to peruse new mass spectrometers and their front-end companions. At this year’s meeting — the society’s 50th — Applied Biosystems and Shimadzu Biotech rolled out the first generations of their QTRAP hybrid triple quadrupole ion trap and Axima-QIT hybrid quadrupole ion trap time-of-flight (TOF) mass spectrometers, respectively. In addition, attendees took particular notice of two front-end systems: the Gyros Gyrolab workstation for transferring protein digests from a 96-well plate to a compact disc for MALDI analysis, and Advion BioSciences’ NanoMate chip and automated nanoelectrospray robot for mass spectrometers compatible with atmospheric pressure ionization.
While some mass spectrometrists might describe vendors as having gone “hybrid crazy,” ABI and Shimadzu are at least hoping they have created novel instruments with unique capabilities. In the case of the QTRAP, ABI, and MDS Sciex — the actual developer of the instrument — see their instrument as having advantages that might particularly appeal to proteomics researchers who also delve into small-molecule quantitation and drug metabolite analysis. “The ion trap is good for sensitivity, and the triple quad is good for selective scans,” said Jim Hager, a senior research scientist at MDS Sciex in Toronto who developed the instrument and described its attributes in a March issue of Rapid Communications in Mass Spectrometry. “There’s something good for quantitative analysis, but also something good for qualitative analysis,” he said.
Shimadzu is also hoping to create a market for its new hybrid quadrupole ion trap TOF mass spectrometer. Through its subsidiary Kratos Analytical, the company hopes that its new instrument will succeed where mass spectrometrists found its earlier versions of MALDI-TOFs lacking. Specifically, the Axima-QIT, as the hybrid is known, combines MALDI ionization to provide repeat analysis capabilities, a quadrupole ion trap for amino acid sequencing and high sensitivity, and a reflectron TOF analyzer for high-resolution detection.
On the front-end side of the equation, LC/MS guru Jack Henion, a Cornell University professor and co-founder of Ithaca, NY-based Advion BioSciences, drew an overflow crowd to his talk on Advion’s NanoMate technology, an automated, chip-based system for sequentially injecting individual samples into atmospheric pressure ionization mass spectrometers without the need for flushing between samples. Henion declined to call the technology “LC/MS on a chip,” instead preferring the moniker “infusion nanoelectrospray,” but added that “if you know me, we’ll be there,” referring to the eventual goal of miniaturizing the entire mass analysis. The chip itself, measuring about two inches by two inches, combined with a robot for injecting samples through each of a 100 nozzles on the chip, allows researchers to analyze 120 samples an hour when acquiring data for 10 seconds on each sample, he said. Because the chips are disposable, Henion said the NanoMate chips and robot package provide dramatic reductions in sample processing time. The robot, at a price of just under $85,000, comes with 20- or 100-nozzle chips, which sell individually for $500.
Seeking to combine MALDI prep with another form of microfluidics, Uppsala, Sweden-based Gyros has launched a robotics platform for transferring individual samples onto a compact disc imprinted with microchannels. Although the technology is currently compatible only with Bruker’s MALDI target plates, Per Sjöberg, Gyros’ executive vice president for commercial operations, said the company has already begun collaborating with Applied Biosystems and Kratos to potentially adapt their MALDI targets for use with Gyros CDs. The advantage of the CD format, he added, lies in the ability to manipulate the sample fluids through microscale separation media using centrifugal force and hydrophobic surfaces as valves. The current, early-stage version of the chip contains 96 individual, 200 nL MALDI targets, each with its own 10 nL reverse phase column. In later incarnations, Sjöberg said the CDs could contain immobilized capture agents — a project being investigated with Affibody — and a fluorescence-based system for detecting binding events.
— JSM