Main specifications for the development of a miniaturized biosensor for sulphite concentration determination in crustaceans and for scale up manufacturing process have been defined. Specifications for materials, processes, subcontractors and manufacturing conditions have served as initial guidelines for suitable biosensor development and manufacture.
The novel sulphite biosensors were constructed by modifying the working electrode of the SPEs with Sulphite oxidase (SOx) enzyme. Amount of each component, working potential and time analysis were optimized in order to achieve the highest sensitivity and stability.
The developed biosensors were applied to:
the detection of sulphite in crustaceans in a linear range of 40 to 120 mg/kg of sulphite with a stability of 180 days obtaining good recovery rates for real samples previously analyzed by the official method, Monier Williams.
the detection of sulphite in water in a linear range of 19 to 76 g/L showing a stability of more than 180 days. During demonstration activities in Ecuador and Honduras, water sample of the bins where shrimps are collected were analyzed and compared to the results obtain with the validated benchtop biosensor BIOFISH 300 obtaining equivalent results (10% error).
Validation activities were carried out for the SO2SAFE biosensors with water samples. The results showed that:
The method is linear.
Sodium sulphite, sodium metabisulphite, potassium metabisulphite and formaldehyde metabisulphite, positive interfering compounds, are also detected by the biosensor.
Recoveries were in the range of 85 to 115% .
SO2SAFE biosensor provided accurate and precise sulphite quantification.
The LOW was established at 13,62 g/l and the LOD at 4,54 g/l.
A miniaturized measuring device, a portable potentiostat, was design and developed to read the disposable biosensors based on SPEs. Different tests were performed to demonstrate compliance with EU Directives regarding electromagnetic compatibility stating that SO2SAFE device complies with them and is suitable for CE marking.
Manufacturing layout of SO2SAFE biosensors is available and tested, a high manufacturing capacity is achieved for screen printed electrodes, enzyme and biofunctionalization and assembly process.
Exploitation of SO2SAFE results will be carried out by direct commercialization of SO2SAFE biosensors from BIOLAN international sales network and through further development of SO2SAFE technology platform into other food safety applications, such as the analysis of malic acid in grapes, musts and wines.
Several activities for demonstration and dissemination of SO2SAFE results were executed by BIOLAN targeted to the main stakeholders and the general audience. During SO2SAFE action BIOLAN attended to the main international trade fairs for the seafood industry in Europe, Asia and Latin America, demonstrated SO2SAFE biosensors performance in real aquaculture facilities of final customers, and launched a multi-media communication package including several videos, posters, and new corporate brand-image. The dissemination of project results was performed through live presentations in several international events launched by the EC, articles in main international journals, and as exhibitor in the main international aquaculture and seefood trade fairs.
