Zip Scientific Fast GC

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1 Case Study I: Improving Lab Productivity with Fast GC Accessories for DRO and BNA Analysis Zip Scientific Fast GC Good People, Top-notch Products and Excellent Service Technical Note 003 Stephen MacDonald Zip Scientific, Hudson NH Introduction GC test methods and equipment play an integral part of nearly every field of chemical testing. A scientist might view GC as a very mature field because both theory and practice are well understood. On the other hand, a lab manager views his fleet of GCs as a financial resource because test results and sample analysis generate revenue. As a result, managers are always on the lookout for faster and more cost-effective ways to streamline operations and maximize the earning potential of their equipment. Fast GCs, new methods, techniques and accessories that can achieve higher sample throughputs are important tools for attaining higher profitability. Fast GC Accessories Thermal agility is a term that describes the ability of an oven to heat up and cool down fast. Both steps comprise the complete cycle time and together they determine sample throughput. Lab managers recognize that cost effective fast GC accessories provide an attractive alternative to buying new equipment because they require little or no bench space and do not eat up extra costs for consumables and support equipment. Zip Scientific manufactures two Fast GC accessories that improve thermal agility. The GC Racer, shown in Figure 1, is a fast temperature programming device. The GC Chaser, shown in Figure 2 can dramatically reduce the oven cooldown step. They can be used individually or together on old or new GCs to reduce cycle time and increase productivity. The pros and cons of Fast GC and both of these accessories are described in more detail in Zip Scientific Technical Note 001. Case Study TestAmerica Laboratories, Inc. ( is a U.S. leader in environmental testing. They have a large network of environmental testing facilities located throughout the United States. The TestAmerica facility in Edison, NJ was selected as the test site for this case study. Both the GC Racer and GC Chaser are used for Diesel Range Organics (DRO) and the GC Chaser is used for semi-volatile Base Neutral Acid (BNA) analysis. Table I summarizes the data demonstrating the productivity gains achieved with these two fast GC accessories. Figure 1. GC Racer Heater installed on an Agilent 5890 GC Figure 2. GC Chaser installed on an Agilent 6890 GC/MSD. Two GCs are dedicated to DRO testing. Each is a dual column Agilent 6890 with both the GC Racer and the GC Chaser installed. Initially the run time was 21 minutes. After installing the GC Racer and adjusting conditions the run time was reduced to 7.25 minutes. This represents almost 3 fold improvement or a time savings of min. The chromatogram is shown in Figure 3. The DRO region for integration starts at 0.50 min and extends to 6.25 min. The remainder of the run serves to bake out the column for the next injection. The surrogate o-terphenyl is seen to elute just after 3.3 min. The rise in baseline is not unusual for these types of analysis whether 1

2 or not fast temperature programming is used. Separate experiments have demonstrated that the GC Racer and fast temperature programming do not cause additional column bleed. See Zip Scientific Technical Note 002 for detailed information on column bleed. Table I. Increased Productivity Data Application DRO BNA GC Model Agilent 6890 FID Agilent MSD GC Racer Yes No GC Chaser Yes Yes Previous Run Time (min) New Run Time (min) Previous Cycle Time (min) New Cycle Time (min) Productivity Increase N/A (GC Racer not used) chromatogram is shown in Figure 4. Fast temperature programming is not a good approach for this application due to the large number of peaks and the limitations of the MSD scan rate. Therefore, the GC Racer is not used and the run times remain the same. On the other hand productivity is very important because GC-MS systems are expensive and these samples generate higher profits. The GC Chaser is a valuable addition in this case. The total cycle time was reduced from 28.0 min to 21.5 min just by cooling the oven down faster between runs. Productivity was increased 1.3 times. Lab Manager Mark Acierno states, We get in about 5 more samples per instrument/per clock. We run 2 clocks a day on three instruments. So 10 extra samples a day X 3 instruments (30 more a day/150 a week). This really helps with rush work. Figure 4. BNA Run with Fast Oven Cool-Down Figure 3. Fast Temperature Programmed DRO Adding the GC Chaser reduced the oven cooldown step from 10 min to 3.25 min. The final tally was that the entire cycle time from one injection to the next was reduced from 31 min to 10.5 min, essentially a 3 fold increase in productivity. For these dual column GCs that resulted in 8 extra samples per hour per GC for a total of 16 extra samples per hour. Base Neutral Acids BNAs were analyzed on an Agilent 5890 GC with a 5971 MSD. Three systems are dedicated to BNAs, each has a GC Chaser. The Conclusion This case study demonstrates the advantages of using Fast GC accessories to increase lab productivity. The equipment is simple to install, requires no operator training and is rugged enough to stand up to the rigorous requirements of 24/7 test lab schedules. In addition to savings gained from not purchasing new GCs these accessories eliminate the need for all of the associated support equipment including additional bench space, columns, autosamplers, computers and syringes. Even the added cost of carrier gas is eliminated by maximizing the potential of the single GC. The GC Racer and the GC Chaser offer an attractive option to lab managers for streamlining operations, reducing costs and maximizing profits. Acknowledgement: We thank Mark Acierno of TestAmerica Laboratories Inc. for data used in this report. 2

3 FL PRO: Here s a chromatogram and report from a Fast GC separation of hydrocarbons ranging from C8 to C40. Run time was less than 6 min. Use the zoom feature on your browser to inspect the peaks closely. Learn more about the GC Racer's Performance Data: Heating Power > Heating Performance > RT Precision Back to

4 Heating Power: The GC Racer can more than double the heating power of the GC. Power can be measured in Volt-Amps (VA). An Agilent GC oven runs on 120V, 13 amp = 1560VA. The GC Racer supplies 1800 VA (120V X 15 amp) additional power for a total of 3360VA heating power. By contrast a fast-ramp oven (240 V X 10 amp) = 2400VA. Q: Why is the GC Racer better than a fast oven? A: More heating power and you don t need 240V circuits. Learn more about the GC Racer's Performance Data: Heating Performance > RT Precision, > Fast Analysis Back to

5 Retention Time Precision for 900 runs over 7 days: The GC Racer performance can be evaluated by measuring the relative standard deviation (RSD) of the RT for each peak eluted at 70 C/min ramp rate. This graph plots the retention time for each peak from a sample containing 16 hydrocarbons from C10 C25. Learn more about the GC Racer's Performance Data: Heating Power > Heating Performance > Fast Analysis Back to

6 The GC Racer is a Fast Temperature Programmer. It overcomes the power limitations of conventional GC ovens by adding a second convection heater to the oven. The GC Racer is controlled by the host GC and can boost ramp rates up to 120 C/min. Advantages of the GC Racer Saves Time Chromatographic Integrity Easy to Implement Fully Integrated Rugged Utility Versatile Cost Effective Faster runs mean higher efficiency, quick turnaround and greater profitability. Does not require specialized columns or interfaces to connect to the injector and detector. Installs in minutes and uses standard columns from any vendor. It is fully controlled by the GC keypad or operating software. No operator training required. Employs the same type of convective heater used in the GC oven. One system can be used for dual column GCs. Can run on V, 50/60Hz and coupled with V GCs. One-fifth the purchase price compared to resistively heated accessories and no expensive specialized columns. Learn more about the GC Racer's Performance Data: Heating Power > Heating Performance > RT Precision > Fast Analysis Interface Copyright 2008 Zip Scientific, LLC - design by

7 Interface: Our Fast GC Accessories interface with the host GC by sensing the current applied to the oven heater. A current transformer snaps around one of the heater wires of the GC. That's it! Simple, Easy, non-intrusive.

8 The GC Chaser is a Fast Oven Cool-Down Accessory. It improves the oven ventilation during the cool-down cycle. It runs completely unattended. It uses room air so it never needs to be refilled. Methods do not have to be re-validated. Advantages of the GC Chaser Saves Time Chromatographic Integrity Easy to Implement Fully Integrated Completely Transparent Rugged Utility Cost Effective Maximizes the workload of GC and GC-MS systems. Higher efficiency, faster turnaround, greater profitability. Methods do not need re-validation. There is no Impact on the separation. Installs in minutes. Automatic, unattended operation. No operator training required. Employs rugged, industrial grade centrifugal blower. It can quickly be swapped to another GC for rush projects. Quickly recovers initial cost and uses no consumables. Learn more about the GC Chaser's Performance Data: Performance Conditions > Cool-Down Comparison > Application Specific Data

9 Fast Cooling Performance: These curves demonstrate the advantage of the GC Chaser. In cooling from 350 to 30 C the GC Chaser saved 9 minutes from the cool-down time. Please view the following slide for more application specific time-savings. Learn more about the GC Chaser's Fast Cooling Performance: Performance Conditions > Application Specific Data Back to

10 Fast Cooling Performance: This table shows actual time savings taken from a working laboratory under optimal temperature and ventilation conditions. Learn more about the GC Chaser's Fast Cooling Performance: Performance Conditions > Cool-Down Comparison Back to