expressLC-ultra^® system fast analysis with excellent reproducibility, while requiring only a small fraction of the solvent used by conventional systems.

The new ExpressLC-Ultra system is breaking new ground in micro-LC technology with its pneumatic pumps, integrated autosampler, ultra-sensitive, full-spectral UV detector, and temperature-controlled column oven. And with Eksigent's intuitive software, users get full system control as well as complete analysis and reporting capabilities.

Now, any chromatographer can take advantage of Eksigent's state-of-the-art micro-LC, running fast analysis with excellent reproducibility, while requiring only a small fraction of the solvent used by conventional systems.

Features-at-a-glance

The ExpressLC-Ultra is designed to run 0.5 mm ID micro-columns at pressures up to 10,000 psi, allowing the use of separation columns packed with <2 µm particles.
The system consists of a binary gradient pump (flow rate range 1-50 µl/ min) with solvent selection for both pumps.
Excellent flow control at these low flow rates is guaranteed through Eksigent's Microfluidic Flow Control technology.
A novel CCD based detector offers outstanding UV sensitivity with full spectral capability, while a micro-fabricated flow cell, with fiber optic coupling, provides minimal post-column dispersion and highly linear response for accurate quantitation.

Download the ExpressLC-Ultra product note

why micro-LC?

For more than a decade, Eksigent researchers and engineers have been developing micro-LC systems that deliver high performance with significant reductions inflow rates. In addition to solvent savings of greater than90%, micro-LC (column ID <1 mm) offers several inherent advantages over both conventional HPLC and UHPLC, such as:

Smaller required mixing volume as a fraction of column volume allows for faster gradient separations.
A lower column flow resistance factor means the same separation can be run at lower backpressure.
The much lower flow rates in micro-LC result in significantly less frictional heating, allowing accurate column temperature control even at UHPLC pressures. This ensures reliable and reproducible retention times across a much wider range of pressures and conditions.
When combined with concentration sensitive detection (e.g., UV absorbance), the smaller ID columns used in micro-LC can provide significant improvements in sensitivity. For example, the same sample mass injected on a 0.5 mm ID column results in an 85-fold sensitivity improvement over a more conventional 4.6 mm ID column.
Lower flow rates provide better compatibility with electrospray mass spectrometry with less source contamination and, depending on source design, also an increase in sensitivity.

With the introduction of Eksigent's state-of-the-art ExpressLC-Ultra, chromatographers can take advantage of the benefits of micro-LC running fast analyses with excellent reproducibility using 90%less solvent.

Integrated autosampler

An industry standard CTC autosampler is included with the ExpressLC-Ultra system. Injection volumes as small as 50 nl can be programmed using Eksigent's metered injection, using the precise and accurate pump flow control in combination with time slicing of a high speed injection valve. The filled injection loop is switched to the inject position for the length of time required to displace the programmed amount of sample to provide precise injections over a range of volumes.

The feature can also be useful in cases where the upper dynamic range of a linear calibration curve is insufficient to cover samples of unexpected high concentration. Instead of diluting the entire series of samples and then re-analyzing, one can simply re-inject the same samples using a smaller injection volume. Multiple injections of the same sample can also be conducted with the metered injection approach. A dual-solvent fast-wash station ensures minimal carryover even for fast separations.

Ultra-sensitive, full-spectral UV detector

A CCD-based UV detector with digital signal processing achieves state-of-the-art noise levels for HPLC detectors with full v spectral capabilities. Using microfluidic-based flow cells, with 5 or 10 mm optical path length and volumes as small as 90 nL,UV detection without sensitivity sacrifice and no extra-column band broadening is achieved. The detector has a maximum data acquisition rate of 100 Hz to keep-up with the fastest UHPLC separation.

Impurity quantitation with low carryover.

Combining the low noise and the highly linear response of the UV detection system in the ExpressLC-Ultra, low level impurity analysis can be conducted. In one separation, a main peak (naphthalene) with an intensity of 1600 mAU is measured along with a minor impurity peak with an intensity of 1.1 mAU shown in the inset. Peak quantitation by peak area indicates a 0.06% impurity. For this separation the impurity has a S/N of approximately 22 indicating a potential LLOQ of approximately 0.03% and a LLOD less than 0.01%. Also shown is a blank injection run immediately after the separation shown. Carryover for the naphthalene at a retention time of 2.3 minutes is measured to be less than 0.01%. Separation conditions: ChromXP C18-EP120 column (0.5 x 50 mm); 15 µL/min; mobile phase A: H2O with 2% ACN, mobile phase B: ACN; isocratic at 60%B;125nL injection; 15 µL/min. UV data collection: 214 nm peak; 10 nm bandwidth; 10 Hz acquisition.

Integrated column oven

he ExpressLC-Ultra includes a column oven designed to allow rapid heat-up and cool-down for use in method development. The oven is designed for easy column changes and accepts columns up to 15 cm in length whil eallowing close-coupling of the column to both the injection valve and the UV detection cell–keeping delay times and extra-column dispersion to a minimum.

Contrary to conventional UHPLC, in microUHPLC the column temperature can be locked to a specified temperature without the loss of efficiency caused by the radial temperature gradient generated by the much higher frictional heating in larger ID columns. This improvement in column temperature control with the new ExpressLC Ultra system ensures reproducible separations over a much larger range of column backpressures.

Temperature effect on separation

Isocratic separation of test mix at five different column temperatures from 30 to 70C conducted in an automated fashion. Separations were conducted sequentially at each temperature with excellent reproducibility. Less than 10 minute equilibration is needed between each temperature change.

Ease of operation

Special attention has been given to making the ExpressLC®-Ultra system as easy-to-use as any conventional LC system. The pumps are self-priming, and solvent selection allows for automated solvent changes during a batch of samples. Plus, the system is designed to allow easy access to the front panel where all of the major components and plumbing are located. The PEEKSilTM tubing and fingertight fittings provide easy-to-use connections even at UHPLC pressures. The fiberoptic connected flow cell is easily installed and exchanged without any required alignment.

green HPLC

In general, HPLC with 2.1 or 4.6 mm ID columns use flowrates from 200 µL/min to over 1 mL/min. The ExpressLC Ultra system running 0.5 mm ID columns at a flow rate of ca. 15 ul/min results in solvent savings of > 90%. Not only will this save money for purchasing solvents and reduce disposal costs, it means you will be contributing to a better environment when you use the ExpressLC-Ultra for your analysis!

Powerful software

Controlling the ExpressLC-Ultra is the Eksigent CDS software. An intuitive interface makes the system easy to learn, and specialized diagnostics tools for troubleshooting are included. Users can rapidly create or modify separation methods, andactive displays for flow rates and pressures allow real-time monitoring of the system operation. With full data analysis and reporting capabilities, Eksigent CDS software is 21CFR compliant and can save data files in AIA standard format.

Drivers for integrating the ExpressLC-Ultra control into Mass Spectrometry software are provided for ThermoFisher Xcalibur, Bruker Daltonics HyStar and ABI/MDS Sciex Analyst.

System specifications

ExpressLC®-ultra (LC only)

Dimensions 29" (74cm) x 25" (64 cm) x 32" (82 cm) (Width x Depth x Height)
Weight 70 lbs (32 kg)
Power 100 – 240 V AC; 350 W

Binary gradient pump with MFCand high pressure mixing

Solvent selection Up to 6 solvents /pump channel
Maximum pressure 10,000 psi
Flow rate range 1 – 50 µL/min (gradients 5-50 µL/min)
Gradient delay volume 1.2 µL (standard configuration)
Flow rate accuracy < 1%
Gradient composition accuracy< 1%
Flow rate precision < 0.5% RSD
Retention time reproducibility < 0.5% RSD

UV detector with full spectral acquisition

Wavelength range 200-375 nm
Minimum selectable bandwidth 1 nm
Noise < 40 µAU (per ASTM)
Drift < 1 mAU/hr
Linearity > 2AU
Data acquisition rate Up to 100 Hz
Available flow cells:
- 10 mmpath length, 180 nl
- 5 mm path length, 90 nl

Column oven

Length for columns up to 15 cm
Ambient +5 °C to 80 °C
Temperature precision 0.1 °C
Temperature accuracy +/- 1 °C

Software

Full control and data analysis software
Plug-ins for ThermoFisher Xcalibur, Bruker Daltonics HyStar and ABI/MDS Sciex Analyst.

Autosampler

Injection valve 10,000 psi with less than 65 nl port to port volume
Injection volume Programmable from 0.05 – 1µL with standard injection loop (larger volumes possible with larger loop)
Injection reproducibility < 1 % RSD for full loop and partial loop
Carryover Typically < 0.05 %
Sample capacity three-drawer sample stack
- Six tray positions
- 54 – 2mL vials
- Standard or deep 96-well microplates
- 384-well microplates
Sample compartments temperature control from 4 to 40 °C
Weight ~65 lbs (30 kg) varies with configuration
Power 100-240 V AC; 4A (additional 2A with cooled sample stack)

Learn more about Eksigent's other ExpressLC systems for pharmaceutical analysis and reaction monitoring:

ExpressLC-800: A parallel HPLC system that screens eight methods simultaneously, allowing you to develop methods
in 1/10th the time.
ExpressRT-100: Real-time monitoring of synthetic reactions for on-the-spot decision making by process chemists.
ChromXP columns: Small-scale columns designed and optimized specifically for the ExpressLC systems.

Search a list of publication citations that describe how leading scientists are using Eksigent ExpressLC systems in drug discovery and development. Or learn more about the application of Eksigent's analytical tools in drug discovery & development:

expressLC-ultra® system fast analysis with excellent reproducibility, while requiring only a small fraction of the solvent used by conventional systems.

expressLC-ultra^® system fast analysis with excellent reproducibility, while requiring only a small fraction of the solvent used by conventional systems.