Multi-analyst diagnostic methods to detect food pathogens

Food safety is dependent on timely detection of chemical, biological and/or microbial risk factors. In most cases one factor is determined in a single test (e.g. ELISA). In general, at-line lateral flow tests allow the detection of one factor as well. Both in view of the time needed to perform a test and with respect to high costs this is far from efficient. The food diagnostic sector is, therefore, looking for multi-analyte diagnostic devices that can be produced at a large scale and in an economically costs-effective way.

Diagnostic methods

Although some multi-analyte ELISAs are available in the human diagnostic sector, the technology would need several improvements to be applicable in the food sector. Lateral flow tests with a microarray of different spots are not commercially available at all. DLO/FBR has built up some expertise in the production of multi-analyte lateral flow and ELISA methods. Together with Scienion and HAN these diagnostic methods can be further developed to commercially marketable products.

Part of the projects activities is focused on large scale production of multi-analyte diagnostic assays and it is anticipated that this can be implemented by the end of the project. The advantage of these multi-analyte diagnostic methods is that the platforms have been known for many years and, in the case of ELISA, can be fully automated on equipment that is widely available.

In addition, low-cost reading equipment is available or will be further developed. Staff time to carry out such multi-analyte diagnostic methods would be the same as for a single-analyte test and, therefore, it is expected that testing can be carried out at much lower cost. This will also drive uptake of testing and encourage the exploitation of diagnostics to improve food safety.

The innovation of the new diagnostic devices will also rely on the ultra-low volume dispensing of reagents (down to 50 picoliter) in a microarray of spots that will enable the simultaneous detection of a range of risk factors in a single sample; 8x8 arrays per well in ELISA and 5x5 arrays in lateral flow tests.

Machine vision technology will be applied to achieve the automated interpretation of multi-analyte diagnostic methods, objectify test outcomes and provide data management. A number of food safety-relevant multi-analyte tests will be developed by the participants and marketed world-wide by ELDC. The meaning of the innovation for the sector will be the availability of highly efficient, multi-analyte diagnostic tests for the rapid (on-site) detection of food safety risk factors.

Furthermore, these new and innovative multi-analyte diagnostic devices can also be adopted by the scientific community to develop multi-analyte assays in other areas. For the society it means increased safety of food products by timely and multi-analyte detection of risk factors. The innovation potential of the new multi-analyte diagnostic devices is high, especially in the human, veterinary, and food safety fields.