Technology base

For biosecurity applications we have developed a technology system based on a universal platform for molecular sample analysis, offering detection of both proteins and nucleic acids.

The molecular technologies are based on a solid scientific foundation described in > 200 scientific publications including Science, Nature Genetics, Nature Biotechnology, Nature Methods and PNAS among others.

Identification of nucleic acids is enabled by the padlock probe (PLP) technology, which combines high selectivity with quantitative response even in a high background of irrelevant nucleic acids. These virtues, together with the ability of the technology to enable highly multiplexed analyses paired with a limit of detection similar to that of PCR, makes it a powerful molecular tool compared to competing technologies. The technology is further suitable for random access type sample flow, enabling a high throughput platform occupying a small footprint.

Protein detection is enabled by the proximity ligation assay (PLA) technology, which is related to the PLP technology, as it is based on the same chain of events that each contribute to high selectivity. The PLA technology has a sensitivity between 10 – 1000 times better than ELISA. This is due to the fact that only reacted probes are amplified. The PLA technology demands as little as one microliter of sample and therefore also enables use for detection in precious and limited samples.

For signal amplification, the system utilizes rolling circle amplification (RCA) and circle-to-circle amplification (C2CA). In RCA a circular target is continuously copied using a polymerase, resulting in a several kilobases long concatenated RCA product (RCP). The product collapses into an amorphous coil of DNA and therefore creates its own compartment. If a specific sequence element is encoded in the circular target molecule, it enables subsequent labelling of the RCP with fluorescent oligonucleotides and easy enumeration via single object counting of strong fluorescent objects similar to what is achieved in standard flow cytometers.

In contrast to many other molecular diagnostic technologies, Q-linea’s Aquila 1000 system uses a single end-point measurement. This means that each sample occupies the detection unit for a short time only. Therefore, the footprint of the instrument can be kept small while allowing a high sample throughput. In addition, this means that the system can accept incoming samples at regular or irregular intervals, without the need to stack up samples on hold and run them in batch as would be the case for a micro titer plate-based instrument, as is commonly used in e.g .quantitative PCR or ELISA assays.

Detection of biosecurity agents

The Q-linea system have been proven to enable proven in a real-world scenario to detect spores spread in a subway environment

Q-linea technology have been used to deliver prototype systems in several projects for customers. Examples include the Swedish Defense Materiel Administration (FMV) and Direction Générale de l’Armement (DGA), France as well as European joint projects such as FP7 funded TWOBIAS, Two Stage Rapid Biological Surveillance and Alarm System for Airborne Pathogenic Threats, and European Defense Agency (EDA) funded IPODS Biological Innovative Point Detection System. The technology is also developed via collaboration with The United States Army Medical Research Institute for infectious diseases.

In the TWOBIAS project Q-linea was responsible for development of an identification module in a two-tier system. The end-of-project full-scale demonstration was performed in the Prague subway. Using simuli agents in a full train traffic situation the Q-linea system successfully and correctly detected spread of the spores that was used as simuli agents with no reporting of false signal in absence of spread of spores.