Fast COVID-19™ is a sample-to-results system with minimal user interaction.
A single system can generate up to 564 patient results per hour.
Once the sample is entered into the system and the patient barcode data is matched to the sample tube, the Fast COVID-19™ platform runs automatically.
The whole process can be viewed as essentially 5 processes:
Data and sample entry
Barcode scanning and pipetting performed by laboratory staff.
Nucleic Acid (NA) extraction
Separation is achieved using “State of the Art” magnetic bead matrices. These are designed to ensure that maximal NA extraction is achieved with minimal contaminating cellular material.
Sample preparation for qPCR
Fast COVID-19™ performs various dilution and liquid transfer steps to combine the purified NA sample with the qPCR test components.
The resulting mix is transferred to the xxplate™ consumable and a heat seal applied to ensure that sample integrity is maintained throughout the qPCR run.
qPCR thermal cycling
Ultra-fast qPCR run is performed using resistive heating technology and takes around 15 minutes to report results.
Reporting of results matched to patient data
Results are exported directly to the patient record (hospital situation) and a printout generated to report the result to the clinician requiring the non-laboratory test eg border authorities at an airport.
Fast COVID-19™ employs the proven technologies developed by BJS and used internationally in the xxpress® NGx thermocycler
Resistive heating technology
By using the xxplate consumable as the resistive heating element in a very low voltage circuit, we can direct and deliver precise amounts of heat. Samples are in a 96 well format on a modified xxplate The system for heating uses a number of discrete power supplies to pass currents through the xxplate via a number of different routes, thus giving multi-zone heating control and ensuring heat is delivered precisely where it is required.
Figure 1. Power Supply Configuration
Figure 2. One of the many combinations for applying current and thus heating specific plate areas.
Figure 3. Thermal image of plate showing heated areas
Figure 4. Diagrammatic representation of a cross section through the xxplate ® showing the intimate relationship between the plate and sample temperatures.
This effect can be visualised using thermal imaging technology.
Cooling of the consumable is by means of several individually controlled air jets giving multi-zone control of cooling too.
Temperature measurements are made using an array of non-contact Infrared temperature sensors.
This heating and cooling is under the control of a complex algorithm. To deliver the temperature response required the control algorithm decides which heating pattern to use and the amount of heat to be generated. This measurement, calculation and heating cycle happens 100 times per second and the system delivers a thermal accuracy and uniformity of ± 0.3°C.
LED excitation channels and CCD emission reading channels
| Channel | Excitation (nm) |
Emission (nm) |
Common dyes |
|---|---|---|---|
| 1. Green | 474 | 507-527 | FAM/SYBR Green |
| 2. Yellow | 535 | 567-583 | JOE/HEX/VIC/TA |
| 3. Amber | 578 | 617-633 | ROX/Texas Red |
| 4. Red | 635 | 667-679 | Cy 5 |
| 5. Deep Red | 662 | 698-724 | Cy 5.5 |
The LEDs excite the fluorophores with a narrow band excitation wavelength this minimises cross talk and ensures the maximum signal is generated even from low abundance Nucleic Acid samples.
The CCD camera will then read the emitted light also strictly controlled through narrow band width filters.
