Why haven’t fast temperature programmers been accepted?
During his work he learned that most if not all laboratory managers voiced similar concerns about HSGC technology.

• Fast temperature programming accessories were too expensive.
• Microbore columns did not have enough sample capacity.
• Special columns and interfaces for the injector and detector were required.
• Fast temperature programmers were over engineered to achieve ludicrously high heating rates. Who needs to go 1200°C/min?
• Implementing HSGC would disrupt lab operations and require additional training.
• Fast temperature programmers were based on unproven technology.
• HSGC was a nice R&D tool but not rugged enough for everyday use.

While voicing concerns with HSGC technology, managers did acknowledge the potential benefits of fast temperature programmers and remained hopeful that a better solution could be found.

What’s wrong with standard GCs?
Nothing is wrong per se, but their heating performance is limited. Dr. MacDonald re-examined fast temperature programming and realized that most GCs were actually capable of providing sufficiently fast heating rates. For example, the highest ramp rate that can be entered in a standard Agilent GC is 70 °C/min for the 5890 model, and 120 °C/min in a 6890. Unfortunately, these rates were limited to relatively low temperatures, less than 100 °C(3). These rates are fast enough to address the vast majority of real world applications. Unfortunately, due to limited electrical power and thermal energy loss to the walls of the oven, these GCs can only heat at much slower rates. In other words, 70 °C/min can be entered for the ramp rate but the oven will not achieve that rate; it will lag behind and heat at a much slower, uncontrolled rate.

The solution.
Dr. MacDonald reasoned that if standard GCs could maintain a fast heating rate throughout the entire useful temperature range of the oven, from ambient to 400 °C, nearly every application could benefit from faster separations. An auxiliary heater was designed to easily slide onto the floor of the GC oven. An electronic circuit was designed to monitor the temperature program of the GC and apply power to the auxiliary heater. Smooth, fast, reproducible heating rates are generated because the main PC board and temperature sensor of the Agilent GC controls both the original heater and the GC Racer. The operation of the GC Racer is transparent to the technician. The ramp rate is merely entered from the keypad or through Chemstation software as before.

Product introduction and deployment
The GC Racer was introduced at the Gulf Coast Conference in 2001. The Celanese Corporation in Bay City TX purchased the first unit soon thereafter. Product rollout was achieved over the following 12 months as petrochemical companies, environmental test labs, hospitals, and forensic labs all purchased the GC Racer. More that 40 units were sold during the first year. Many customers purchased additional units after they saw the benefits of their first GC Racer.

Establishment
Today, the customer list continues to grow and the GC Racer has invaded Europe. The product has gained widespread acceptance largely by word of mouth and a very small marketing budget. Simplicity, ease of use, affordability and durability has earned a solid reputation for the GC Racer as a useful HSGC accessory for Agilent 5890 and 6890 GCs.

References
1. Patent Number 6485543
2. Patent Number 5808178
3. These values are cited for typical US installed GC Racer. Faster ramp rates are possible with 240V ovens. Please refer to the Agilent website for a complete list of specifications.

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