Why Automate Microbial Testing in the Micro Lab?

As a mechanical engineer, I've marveled at how automation has been revolutionary to so many industries.  For automobiles, electronics, and consumer products, the incorporation of more highly automated and streamlined systems necessitates changes in how manual processes are performed; allowing those industries well documented improvements in time to market and cost control.

For the micro lab, automation is in its infancy. Most processes are manual and done in batch style -- collect a bunch of samples, do a bunch of filtrations, count a batch of plates.  If any one step is late, humans are good at correcting or making up the slack in a later batch step - maybe we work late that shift. 

Automation changes that way of thinking, since systems function more smoothly when they are fed with a continuous supply of samples, and every aspect of the system can be kept running at 100% capacity over 24 hours. Automated systems deliver maximum process savings and ROI when the supporting manual processes are also optimized to support the automation and thus minimize the need for a human analyst's time and effort.

When we designed the Growth Direct^TM system, we were conscious of the need to "leave the micro alone" - that is to design a system that fundamentally did not alter the traditional method of plate counting on agar, and that could therefore fairly claim equivalence to compendial methods.  That put a strong premium on forcing the system to accommodate the peculiarities of the cassette - the imprecise agar surface, the variegated membrane texture, and the inherent randomness of microbiology itself.  It meant a lot of precision engineering just to ensure we could deliver a faster answer without affecting growth or fundamentally changing the basic assay.

We also wanted the system to provide "walkaway automation" - after a sample preparation step that effectively replicates current practice. The user places a stack of cassettes into the machine, closes the door, and walks away.  The tightly integrated system which includes robotics and incubation allows the rapid enumeration assay to proceed 24 hours a day as efficiently as possible. 

The brains behind the system provides a user interface to allow users to schedule jobs of samples with minimal complexity, but in a framework that lets the system minimize slack time and ensure results are posted quickly and on a predictable schedule.  Multiple robotic handling systems allow Growth Direct to juggle cassettes, regardless of the assay methods being run.  Automatic alarm notification systems can alert users to action limits being exceeded, error conditions, or other issues quickly via email, while assay results can be posted automatically to a LIMS system and delivered in the customer's choice of custom report format. 

The result is a highly-automated, high-throughput microbiology laboratory that can function as a manufacturing center of excellence.  Results are delivered quickly, but, more importantly, nothing significant changes in sample preparation or enumeration from a microbiological point of view - a tremendous advantage when it comes time to get the system validated and actually put into use.  The fastest method is of no use if it only works in the laboratory. Return on Investment from the rapid enumeration solution depends on operation in a factory environment where the system is in constant use.  Speed of implementation is therefore just as critical as speed of assay - even more so, since without the former you'll never get a chance to see the latter.

We are initially seeing customers use the system simply as fast, automated colony counter.  It has not been long before users started to see that this only scratches the surface.  By making a few changes in process - such as hooking up to LIMS, processing samples in optimized batch sizes and making efficient use of the system scheduler - the Growth Direct system becomes a fully automated microbiology workcell, requiring very little human interaction after sample preparation.  That's when automation does what it has done in other areas - allow users to get the benefits of rapid microbiology without any extra work in sample prep, sample analysis, or data recording.

This is an exciting time for the Pharma lab.  Review our pages on Growth Direct for more information on the technology.

Sarath Krishnaswamy
VP of Development
Rapid Micro Biosystems