27 Mar Safe food – a safer world around us
(blog post header photo source: www.ift.org)
Minja Mladenović & Dr Marko Radović
BioSense Institute
Food safety is still one of the most significant public issues. Foodborne diseases, caused by pathogenic microorganisms, continue to occur worldwide. The bacterial pathogens and toxins which cause foodborne illnesses, present a threat to public health and increase the risk of significant economic losses. Poultry pathogens are of particular importance since poultry is the second-most usually consumed meat worldwide and it is considered the main source for two of the most frequent human foodborne diseases: Campylobacteriosis and Salmonellosis.
According to the World Health Organisation (WHO), food insecurity causes 600 million food cases and 420,000 deaths annually. Thirty percent of deaths related to foodborne diseases occur among children under 5 years of age. WHO estimates that 33 million years of healthy individuals are lost due to the global consumption of unsafe foods each year, and this number is probably an underestimate.
Figure 1. Foodborne diseases statistic from WHO
Point-of-care diagnostic of agrifood pathogens
Conventional methods for pathogen detection and identification are time-consuming and require up to 7 days to provide final results. Therefore, improvements in pathogen monitoring methods are truly necessary. The development of rapid, accurate and sensitive methods for the identification and detection of pathogens that are directly applicable in the production chain is essential to recognize diseases at the earliest possible stage. Novel on-site biosensing systems for early detection of foodborne pathogens have to provide sensitive and specific biomarker detection, as well as to enhance the robustness of the bioassay to adapt it for in-field applications.
Figure 2. Flashdiag technology for on-site diagnostic developed by Anova-Plus – member of the IPANEMA consortium
Point-of-care microfluidic biosensors provide many possibilities for the agrifood industry. Biosensors utilize the specificity and sensitivity of biological systems in small, low-cost devices and enable analysis and screening of food items during all phases of production providing more adapted and more efficient tools to ensure food safety. Current biosensor research is directed towards the integration of Nucleic Acid Testing (NAT) into microfluidic devices. Furthermore, paper-based isothermal NATs provide an alternative to expensive and time-consuming conventional NATs. Applying POCT-friendly isothermal NATs (isoNATs) facilitates the detection and development of a low-cost system for in-field measurements.
Figure 3. An integrated paper-based biosensor with sample-in-answer-out capability developed by Xi’an Jiaotong University – member of the IPANEMA consortium
Microfluidics, a technology of manipulating the small quantity of fluids in a network of microchannels, can integrate into a single chip a number of operations, such as sample pre-treatment and preparation, cell separation, mixing and/or separation of fluids or cells together with micromechanical, optical, and electronic components for sensing and detection. The chip design can be optimized to accommodate on-chip storage of the isoNAT reagents, pre-loaded in a stabilized form, as well as reservoirs for buffers liquids. The confinement of the sample into the microfluidic environment of the device reduces the risk of sample contamination and minimizes the sample volume and reagents required for the assay. Combining different detection principles with paper-based isoNATs and the microfluidic device enables the development of fully integrated pathogen biosensors.