One of the world's premier conferences and expositions on laboratory science, the Pittsburgh Conference on Analytical Chemistry
and Applied Spectroscopy (Pittcon) is a showcase for the latest advances in laboratory instrumentation and technology, attracting
all of the major high performance liquid chromatography (HPLC) vendors in addition to more than 900 exhibiting companies from
around the world. Pittcon is a great place for vendors to introduce, and scientists to see, touch, evaluate, compare, and
hear all about the latest in HPLC technology. This installment will highlight some of the new HPLC and related technology
showcased both before and at this year's conference.
This year, the Pittsburgh Conference on Analytical Chemistry & Applied Spectroscopy (Pittcon) was held on March 11–15 at the
Orange County Convention Center in Orlando, Florida. The conference, which annually attracts more than 15,000 attendees from
industry, academia, and government from 90 countries worldwide, is sponsored by the Spectroscopy Society of Pittsburgh and
the Society for Analytical Chemists of Pittsburgh. Pittcon 2012 had more than 900 exhibitors registered to appear in more
than 1800 booths. Upwards of 2000 technical presentations and nearly 100 short courses also were given. The conference provides
a great opportunity for vendors to expose new high performance liquid chromatography (HPLC) products to both new and existing
customers, and with this fact in mind, many HPLC vendors have coordinated their new product development cycle around Pittcon
for years, introducing new technology at the conference for the first time. Although the proliferation of smaller specialized
conferences has in recent years altered this approach, for example, many new mass spectrometry (MS) product introductions
are now made at the annual Conference on Mass Spectrometry and Allied Topics (ASMS), Pittcon still remains a must-go-to meeting
to see the latest and greatest in HPLC and related technology. However, this year marked the first time that at least one
HPLC vendor decided to go completely virtual, and instead of attending Pittcon, chose to offer a series of local seminars
and on-line web-based e-conferences instead. For the attendees, the conference provides a venue to evaluate the latest instrumentation,
compare vendors, participate in product demonstrations, and speak with technical staff to resolve problems or investigate
potential applications. It will be interesting to see how things play out in the virtual world.
At this years' Pittcon, several vendors introduced new systems, software, and components, as well as product line extensions.
In this installment, I'll review some of the new HPLC and related instrument technology shown virtually and physically at
the conference. Table I lists the company introductions that are reviewed in this column. (New column and sample preparation
technology will be reviewed by Ron Majors in the April and May installments of Column Watch.)
Table I: Summary of systems and components reviewed in this article
Supercritical Fluid Chromatography
Supercritical fluid chromatography (SFC) has been commercially available since about 1982, but more recently it has gained
in popularity because of advances in technology and applications to several difficult separation challenges (for example,
the separation of chiral compounds). SFC is a form of normal-phase chromatography that is used for the analysis and purification
of low- to moderate-molecular-weight, thermally labile molecules. The theory and principles of SFC are similar to those of
HPLC; however, SFC can be differentiated from other chromatographic techniques (gas chromatography [GC] and HPLC) by the use
of a supercritical fluid as the mobile phase and, therefore, the entire chromatographic flow path must be pressurized. SFC
has several advantages compared to GC and HPLC methods, including rapid separations without the use of organic solvents, reduced
use of organic additive chemicals, and the use of carbon dioxide collected as a by-product of other chemical reactions (or
collected directly from the atmosphere), thereby contributing no new chemicals to the environment and promoting "green" chemistry.
In addition, SFC separations can be done faster than HPLC separations because the diffusion of solutes in supercritical fluids
is about 10 times greater than that in liquids (and about three times less than in gases). The lower diffusion results in
a decrease in resistance to mass transfer in the column and allows for fast, high-resolution separations. Compared to GC,
capillary SFC can provide high-resolution chromatography at much lower temperatures. This allows for the fast analysis of
thermolabile compounds. Many vendors have recognized these advantages and have started to offer SFC instruments on existing
HPLC and ultrahigh-pressure liquid chromatography (UHPLC) platforms.
Agilent offers three points of entry into SFC: the original 1260 Infinity Analytical SFC instrument; a Hybrid SFC/Ultra High
Pressure Liquid Chromatography (UHPLC) system; and an upgrade path based on the Aurora Fusion A5 Evolution system that converts
existing Agilent 1100 and 1200 HPLC systems to SFC. The Agilent hybrid SFC/UHPLC system is based on the 1260 Infinity Analytical
SFC system, but adds both a quaternary or binary HPLC pump and a two-position 10-port valve to be able to switch between UHPLC
and SFC and provide true orthogonal separations at pressures as high as 9000 psi. The hybrid system is capable of screening
methods by switching between SFC and UHPLC in a single run sequence, significantly reducing cost (only one system to purchase),
laboratory footprint, equilibration time, and instrument-to-instrument variability. Figure 1 shows an example of both an UHPLC
and a SFC separation of a mixture of polycyclic aromatic hydrocarbons (PAHs) on the hybrid system.
The new Aurora SFC Fusion A5 Evolution system is built on the original Aurora SFC Fusion A5 instrument and features a combination
of optimized pumping technology with an ultralow-noise back-pressure regulator. The upgrade kit allows full conversion of
an Agilent 1100 or 1200 series HPLC system to a full analytical SFC system that moves SFC smoothly into routine laboratory
analyses with enhanced features for full qualification in a good laboratory practice (GLP) or good manufacturing practice
(GMP) environment. With cost containment being the focus of many companies, conversion can reduce the overall cost of entry.
Four orders of magnitude of dynamic range provide accurate quantitation of 0.01%-level impurities, high precision, HPLC-like
sensitivity, and UHPLC speed using UHPLC columns. The system is fully compatible with the manufacturer's chromatography data
At past shows, Waters has showcased its SFC system, the Waters Acquity UPSFC system that is built on the Waters UPLC sub-2-Ám
particle chemistry platform. The UltraPerformance SFC (UPSFC) system is designed to incorporate all of the advantages of SFC,
in addition to superior separation, resolution, and speed afforded by the sub-2-Ám particle chemistry platform. This year,
Waters introduced the UltraPerformance Convergence Chromatography Acquity UPC2 system, which gives scientists the ability to precisely vary mobile-phase strength, pressure, and temperature. With the
ability to fine-tune the resolving power and selectivity of the system, scientists can exercise better control over the retention
of analytes for separating, detecting, and quantifying structural analogs, isomers, and enantiomeric and diasteriomeric mixtures
— all compounds that are often difficult to separate by any other means. Its key features include
- A 10-ÁL fixed-loop injector for partial-loop injections of between 0.5 ÁL and 10 ÁL, which preserves sample and eliminates
the need to change sample loops.
- Reduced system volume, which enables shorter run times, optimizes gradient performance, reduces band broadening, and enables
the use of small-particle-size columns.
- Cosolvent and column switching for more flexible method development, and faster solvent and column screening.
- Gradient accuracy and precision for retention time reproducibility.
- Improved optical detection and MS compatibility for conducting both qualitative and quantitative analyses.