Q: How can an automation system help safeguard against false negative pathogen results?
Pathogen testing can typically be broken up into three categories:
- Raw material testing;
- Finished product testing; and
- Environmental monitoring.
Regardless of the type of testing that is done, it is clear that pathogen detection is an important component of any hazard analysis and risk-based preventative control program. Verification of results is crucial, particularly negative results. When performing pathogen testing with a real-time PCR based assay, the presence of an internal amplification control is critical. When present for each individual sample, the internal control monitors for inhibition, which can be common with matrices such as spices and chocolate. When a negative result is obtained, it is important to know if that sample is truly negative because the pathogen of interest is not present or if the reaction was inhibited.
Another potential for false negative results can come from technician error. If a sample is not actually added to the reaction block, tube or strip for testing, the result will be negative. Therein lies the power of an automation system. The iQ-Check Prep automation system employs a liquid level sensing volume verification step at the beginning of the run. Utilizing monitored air displacement technology and conductive pipette tips, users are alerted if a sample was missed in the setup. The user then has the option to add the sample or skip it and continue the run. If the sample is not added, the result is flagged as invalid. Combining the internal control of iQ-Check real-time PCR detection kits with the verification of the iQ-Check Prep automation system, users can be confident in their results and safeguard against false negatives.
Q: How can an automation system be incorporated into a laboratory without disrupting existing workflow?
Incorporating an automation system into a laboratory can greatly increase efficiency, traceability and throughput…if it is the right solution for the lab. Many factors need to be taken into consideration, for example batch processing. Examining time intervals at which samples finish incubation can determine how batch processing fits into the lab workflow. Technician responsibilities also play a part. Does the system require monitoring and continuous feeding of samples or is it a walk away system that frees technicians up to perform other lab duties? Another important consideration is maintenance. The scheduled upkeep of the system needs to be evaluated not only for the amount of time required but for the cost associated with the maintenance.
The iQ-Check Prep system was designed with efficiency in mind. Samples are processed in batches (plates of 94 samples at a time) for a throughout of >500 samples per instrument per eight hour shift. The system is a true walk away system that does not require constant monitoring or continuous feeding. The maintenance is self-contained and completed by the instrument in 5 minutes. These are just a few questions to ask when considering an automation system for the laboratory. The chosen system should fit effortlessly into the laboratory workflow and increase throughput and efficiency without causing major disruptions.
For more information, visit Bio-rad.com.