MS. - Analytical

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product review

HPLC and the ever popular LC/MS Bioanalytical applications continue to drive the market. Britt E. Erickson

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t the 15th International Mass Spectrometry Conference held in August in Barcelona, Spain, an eminent mass spectrometrist declared, “Throw away separations and proteolysis. The mass spectrometer is not a bad separator,” while another mass spectrometrist claimed, “You don’t need separations. Identify mixtures directly by MS.” Perhaps that is the direction analytical chemistry is heading, but many chromatographers would beg to differ. Separation scientists can rest assured. With worldwide revenues estimated at over $2.5 billion annually, HPLC is not about to disappear anytime soon. Chromatography continues to dominate the analytical instrument industry, and hyphenated techniques such as LC/MS and LC/MS/MS are growing at a phenomenal rate. Driven by the booming life sciences market, LC/MS sales are expected to continue soaring at doubledigit growth rates as the technique gains wider acceptance. The overall HPLC market is complex with many players involved. So many that it would be virtually impossible to profile them all in a review of this length. HPLC is a mature technique, and as one researcher put it, after more than three decades of refinement, HPLC systems have become somewhat “generic”. Nonetheless, this review is intended to provide a general survey of the current state of commercially available HPLC systems. A summary of selected HPLC

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Table 1. Summary of representative HPLC systems. Manufacturer

Model

Software

Description

Specialty areas/Targeted applications

Agilent Technologies P.O. Box 10395 Palo Alto, CA 94303 800-227-9770 www.chem.agilent.com

Agilent 1100 Series

ChemStationPlus

Integrated low-cost to high-throughput HPLC systems; capillary to preparative flow rates; GPC–SEC, LC/MSD, or LC/MSD ion traps; or as stackable modules

Biopharmaceutical research, highthroughput applications, pharmaceutical QA/QC, polymer characterization, environmental and food testing

Alltech Associates 2051 Waukegan Rd. Deerfield, IL 60015-1899 800-255-8324 www.alltechweb.com

N/A

AllChrom

Modular HPLC and IC systems

IC, evaporative light-scattering detection (ELSD 2000) for HPLC

Amersham Pharmacia Biotech ÄKTAdesign 800 Centennial Ave. P.O. Box 1327 Piscataway, NJ 08855-1327 800-526-3593 www.apbiotech.com

UNICORN

Platform of systems, control software, and High-throughput biomolecule pre-packed columns for protein purification purification

Beckman Coulter 4300 N. Harbor Blvd. P.O. Box 3100 Fullerton, CA 92834-3100 800-742-2345 www.beckmancoulter.com

System Gold

32 Karat

Modular microbore HPLC system, capable Microbore applications and automated of handling 1 µL/min to analytical flow rates methods development

Bioanalytical Systems 2701 Kent Ave. W. Lafayette, IN 47906 800-845-4246 www.bioanalytical.com

«psilon

ChromGraph

Modular isocratic and gradient HPLC systems for either analytical or microbore applications

Specialized instrumentation for LC, in vivo sampling (microdialysis and ultrafiltration), and electrochemistry. Drug metabolism research, pharmacokinetics studies, pharmaceutical analysis, neuroscience, environmental science, clinical chemistry, and forensic science

D-Star Instruments 8424 Quarry Rd. Manassas, VA 20110 800-378-2712 www.d-star.com

DIS- (isocratic) and DGS-series (binary gradient)

Star-Chrom

Low-cost (starting at 1 mL/min. Other factors to consider include pH, solvent type, and solvent additives (1).

Acquisitions, alliances, and name changes The benchtop LC/MS market has undergone several changes since Analytical Chemistry reviewed electrospray MS three years ago (Anal. Chem. 1997, 69,

Nearly all commercially available API-based LC/MS systems have the ability to switch between ESI and APCI. 427 A– 432 A). At that time, representative LC/MS manufacturers included Finnigan, Hewlett Packard, Micromass, and Perkin Elmer/Sciex. Although some new LC/MS instruments have been introduced since 1997, the biggest changes in the industry have been the result of company acquisitions, alliances, and name changes. To give some indication of the dynamics of the LC/MS market, all four companies profiled in 1997 are now operating under different names. Finnigan became part of ThermoQuest, adding its LCQ ion trap LC/MS system to ThermoQuest’s product line. The instrument has since undergone further development and is now available as either the LCQ DUO MS/MS, which is marketed as being compact and affordable, or the LCQ DECA MSn for ultrasensitive applications. ThermoQuest’s newest LC/MS system, Fast LC/MSn, was introduced this year at Pittcon and includes software for proteomics, drug discovery, metabolism, and clinical trial applications. The Fast LC/MSn includes a Surveyor LC System integrated with either the LCQ DUO MS/MS, LCQ DECA MSn, or Finnigan TSQ (triple quadrupole). Hewlett Packard (HP) split into two companies in 1999. What used to be HP’s analytical instrument business now operates under the name Agilent Technologies. Agilent’s 1100 Series LC/MSD is still a major force in quadrupole LC/ MS, and the company has now added an ion trap to its product line, the LC/ MSD Trap system. Agilent recently in-

Although some new LC/MS instruments have been introduced since 1997, the biggest changes in the industry have been the result of company acquisitions, alliances, and name changes.

troduced the 1100 series Capillary LC system, which is designed to accommodate limited sample volumes. Highthroughput LC/MS modules, such as the Agilent 1100 and 220 well plate samplers, are also now available. Waters Corp. also got in on the action and acquired U.K.-based Micromass in September 1997 to enhance its position in the LC/MS market. Although Micromass offers several high-end MS products (e.g., triple quadrupole, time-offlight, and Q-Tof systems) that can be interfaced with chromatography, Waters has focused its efforts exclusively on single quadrupole LC/MS systems. Readers are encouraged to contact Micromass for details on their higher-end MS products. The newest addition to Waters’s LC/MS product line is the Waters ZQ, a single quadrupole API-based MS detector, which is being marketed as compact, sensitive, rugged, and affordable. The ZQ is controlled by the new MassLynx software, which has options for combinatorial chemistry, autopurification, and protein/peptide applications. Waters also recently introduced a new capillary LC/MS system, the CapLC/ MS, which is geared toward drug discovery, proteomics, and other applications with limited sample volumes. It too is controlled by MassLynx software. In addition to its newer products, Waters offers the Integrity, an electronimpact (EI) LC/MS system, which was first introduced in 1994. The Integrity is one of the few LC/MS systems still on the market that is based on particlebeam technology. According to Waters, unlike most particle-beam systems, it has the ability to handle aqueous mobile phases. The Integrity System gives library-searchable MS and UV–vis spectra from a single injection and is targeted after chromatographers in need of identifying unknowns. Perkin Elmer has also undergone its

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share of splits and name changes. In 1999, the company sold its analytical instruments (AI) division to EG&G, leaving behind a new company named PE Corp. to focus on the life sciences market. EG&G went on to change its name to PerkinElmer, and what used to be PE’s AI division is now called PerkinElmer Instruments. Although they do offer an HPLC system, PerkinElmer Instruments is not concentrating its efforts on LC/MS. On the other hand, PE Corp. is. Under PE Corp. reside Applied Biosystems, PerSeptive Biosystems, PE Informatics, and Tropix, all of which now conduct business under the name Applied Biosystems. Applied Biosystems offers a wide range of LC/MS/MS products, including the quadrupole API 3000 and API 2000 LC/MS/MS (developed in collaboration with Sciex), the QStar hybrid

quadrupole TOF LC/MS/MS, and PerSeptive’s Mariner API-TOF system. Shimadzu entered the LC/MS market with the introduction of a new APIbased quadrupole MS detector for its VP Series HPLC systems. In 1998, Hitachi introduced the M-8000 LC/3DQ MSn, an API-based quadrupole ion trap LC/MS system. LECO acquired the Jaquar ESI-TOF technology from Sensar Larson-Davis in 1999, enhancing its TOF product line. To add to the competition, Bruker Daltonics introduced the BioTOF II, an ESI-TOF system designed for elucidating protein structures and noncovalently bound compounds. In terms of alliances, Agilent and Bruker teamed up to create the Agilent 1100 Series LC/MSD Trap and Bruker esquire3000 ESI LC/MSn. The two systems have nearly identical ion trap mass spectrometers, which combine Agilent’s

ion source, ion optics, and vacuum system technology with Bruker’s ion trap mass filter technology. Both use Agilent’s 1100 Series HPLC system. ThermoQuest formed alliances with several HPLC manufacturers, including Dionex and Gilson, allowing them to combine the Finnigan AQA benchtop API-based MS detector with their HPLC systems. Dionex now offers LC/MS and IC/MS (ion chromatography) systems with the Finnigan AQA. All that in only three years. Britt Erickson is an associate editor of Analytical Chemistry.

Reference (1)

Voyksner, R. D. Combining Liquid Chromatography with Electrospray Mass Spectrometry; In Electrospray Ionization Mass Spectrometry; Cole, R. B., Ed.; John Wiley & Sons: New York, 1997; pp 323–341.

1/2 horizontal ad 716 A

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