Fast MDx shows how many pathogens can be detected with unrivalled speed without the need for expensive biosafe laboratories. This London-based company developed a near-patient test system that cuts the typical waiting time of 24 to 48 hours to just one to two hours. The new system uses automation technology from Festo.
Covid-19, influenza A, influenza B, RSV-A, RSV-B: it is important that doctors are able to reliably determine the most common respiratory pathogens in one to two hours so that infected people can quickly receive personalised treatment. The test platform is usually set up close to the patient in hospitals, clinics or doctor's surgeries.
"The fully automated, point-of-care and high-throughput test platform is mobile and can therefore be used anywhere. Only one technician is required to operate it, rather than the five normally needed in a central laboratory to process up to 1,000 patient samples in an 8-hour shift," says Richard Lewis, founder and CEO of Fast MDx.
The Fast MDx platform relies on automation technology from Festo for pipetting and dispensing. Automated testing systems save technicians time and reduce the human errors associated with manually pipetting hundreds of samples into standardised tubes and microtiter well plates. "Fast MDx is a fully integrated system that includes everything needed for the test, from the sample tubes and swabs to the electronic transmission of results to the hospital, clinic or doctor's practice where the sample was taken," Lewis explains.
The tests on the Fast MDx platform are fully automated. Included in the system are handling gantries with electric linear actuators from Festo for precise pipette handling and for robot-assisted handling of the PCR microtiter plates, heat sealing from Kbiosystems and the patented, ultra-fast qPCR thermal cycler NGX2 from Fast MDx. The Biosero software used on the platform integrates and controls all the modules and makes operation very easy. The British special machine builder Applied Automation is responsible for the design of the complete test system as well as for all aspects of safety, risk analysis and CE marking.
The operator places the racks with the pipette tips, the microtiter plates, the assay kit with all the reagents and the patient samples. These are tracked throughout the process using a unique bar code that is laser etched onto the bottom of each customer sample.
During sample preparation, the planar surface gantry EXCM from Festo operates in the X and Y planes. The 92 patient samples are scanned from below using optical sensors from Festo to confirm that all the samples are present. The automated pipetting system, consisting of the Festo pipetting head DHOE and the disposable syringe ejector DHAO, is mounted on the planar surface gantry in the Z direction. The pipetting head can accurately dispense volumes in the range of 10 µl and the pipetting speed can be adjusted to dispense up to 10 ml/s.
The master mix is prepared, placed in the microtiter plate and then the samples are added. The disposable tip pierces the cap of the patient sample, after which it aspirates and pipettes each one into the master mix in one of the wells of the microtiter plate. To avoid cross-contamination and incorrect results, each tip is only used for one patient sample and then discarded. "Piercing the cover saves a lot of time and money, as no conventional opening and closing systems are required and it eliminates human errors that so often happen when manually pipetting hundreds of samples into tubes," explains Hannes Rößer, handling technology expert at Festo.
A separate handling system, based on the planar surface gantry EXCM-30, uses electric gripper EHPS-16 to pick up the filled microtiter plate and place it in the heat sealer, where it is sealed with a plastic film. The sealed plate is then placed in the RT block, which triggers the conversion of the RNA, if present, into complementary DNA (cDNA). In the final step, the PCR reaction takes place to determine whether the cDNA sequence of the pathogen of interest is present in any of the patient samples tested.
To avoid having to use an external pneumatic supply, the Fast MDx test platform uses the pressure and vacuum generator PGVA from Festo, which produces a pressure or vacuum of +/-0.5 bar. Only a 24-volt power supply is required to provide a pressure and vacuum solution with compressed air. The PGVA integrates a mini compressor, air filter unit, reservoir and electronic pressure and vacuum control in a very small space, providing a totally self-contained solution for liquid handling in laboratory automation.
"Thanks to the close cooperation between Fast MDx and Festo, we were able to build the first prototypes quickly and efficiently despite the extremely high complexity," says Richard Lewis, CEO of Fast MDx. "We were able to combine Fast MDx's extensive expertise in qPCR thermal cycling with Festo's proven 3D gantries, controllers and pipetting systems."