The availability of small automated instruments has made automation more affordable, easier to use, simpler to implement, and has also uncovered a host of additional benefits.
Manual sample extraction and processing are still the norm in many forensic DNA laboratories. Typically this requires organic or filter-based DNA purification methods that are time consuming, labor intensive, and whose success may vary by analyst. Following DNA extraction, samples need to be quantified and normalized prior to STR amplification and analysis. Each analyst typically performs all of these steps for only the casework or reference samples assigned to them. This approach has been quite successful, but can be tedious and can lead to inconsistency depending on the ability and training of the analyst performing the steps in the process. One way to address these issues is to automate sample processing. In taking this approach, it is important to ensure that the automation involved is simple to use, easy to implement, and integrates with the workflow of the lab. In addition, labs need to consider how much time and effort are required to validate an automated system and how likely the lab is to include it in their sample processing workflow.
Advantages of Low Throughput Automation
It is too often assumed that the instrumentation required for automation is too complex and expensive to be adopted by the majority of laboratories. In addition, many consider the main advantage in automating any process to be the ability to increase sample throughput to 96 well or higher levels. These assumptions are often true of large automated liquid handlers and the processes they are used to automate. However, the availability of smaller automated instruments offering lower throughput has made automation more affordable, easier to use, simpler to implement, and has also uncovered a host of additional benefits. These include convenience, increased sample to sample consistency, walk away sample processing, and the ability to handle small numbers of samples quickly and without the need for batch processing. For the forensics lab, the trade-off for all of these benefits, is that Personal Automation™ instruments are focused solely on automating the process of nucleic acid extraction. While this could be seen as a limitation, it also makes them easier to incorporate into laboratories that prefer most of their workflow processing remain manual.With their lower throughput (in the 1- 16 sample range), individual analysts can use these instruments to process their cases without the need to batch samples. Because these smaller instruments perform a limited set of processes and are easy to use they also tend to be less work for labs to validate and more likely to be incorporated into a lab's workflow.
Interestingly, Personal Automation can also serve a useful function in labs that have already adopted larger automated liquid handlers. Automated liquid handlers can process large numbers of samples, but this requires analysts to batch their samples so as to use the instrument most efficiently. However, there are situations like "rush" cases where small numbers of samples need to be processed in a timely manner. In these situations, it may be optimal to use a smaller style of Personal Automation to quickly process those samples rather than waiting to batch samples and taking the time to set up a complex automated process. The use of dedicated extraction instruments allows the analyst to avoid batching samples but maintains many of the benefits of automation. Consistency in extraction performance can be maintained because both the larger and smaller platforms can use the same chemistry. As you can see, even when an automated liquid handler is available in a lab there can still be a place for smaller Personal Automation.