That experience and the technological improvements that were pioneered here at Ted Pella^®, Inc. have directly benefitted the diagnostic, research and academic communities (see Recent Literature) over the last 10 years. In the last 12 years we have hosted over 30 hands-on microwave processing workshops that have demonstrated the versatility of the equipment, the time savings achieved (see table 1) and the superior quality of the processing results (see images). Less apparent might be the technological advancements over the years (see development history).

These advancements include:

ColdSpot™ US Patent #6329645:
This accessory (see PELCO ColdSpot™) significantly improved sample temperature control which improved reproducibility and processing results. This device made it possible to standardize the current processing applications. Infrared images have demonstrated that reflected microwave energy is absorbed and sample heating is reduced or eliminated by its use. Why deal with hot and cold spots when you don’t have to.

True Variable Wattage:
The first true variable wattage microwave, for any application, came from Ted Pella^®, Inc. Magnetron power can be set for any wattage between 100and 750W through the touch of a finger. Sample temperature control was improved dramatically and the horizons for microwave use were expanded (e.g. in vivo labeling, in situ hybridization, multiple labeling, improved fixation). Reproducible protocols for electron microscopy, paraffin processing, decalcification and immunolabeling were made possible by this development.

Digital Control and Programmed Processing:
A significant advancement to tissue processing, immunolabeling, decalcification and formalin fixation. Preprogrammed protocols make this development invaluable in multi-user or core lab setting. It made automation possible for a number of applications, like decalcification and formalin fixation. Sample temperature control is improved with programmed safeguards.

Internal Vacuum and Water Circulation Systems:
The only microwave manufacturer to integrate these systems into a single unit. The importance of vacuum to fixation and infiltration has been established experimentally as has the role of water recirculation to sample temperature control in conjunction with the ColdSpot™. A special microwave transparent and chemically resistant vacuum chamber was developed to go with this system.

Automatic Magnetron Prewarming:
The magnetron filament is automatically preheated prior to every run to ensure that 100% of the power selected is delivered for 100% of the time chosen.

SteadyTemp™:
This was added technology to control or eliminate (see SteadyTemp™) microwave-induced sample heating. Used in conjunction with the ColdSpot™ , variable wattage and digital control and programmed processing it has been instrumental in helping to understand the true benefits of microwave-assisted sample processing.

Summary:
The control of sample temperature and magnetron wattage have been the keys to effectively adapting microwave radiation to a laboratory environment. In our pursuit of better equipment and techniques a microwave has evolved, The BioWave® Pro, that is both versatile in application and easy to use.

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