(602p) Sensor Paper for Food Safety Applications Using Enzyme Immobilization on Diatoms

A low cost and scalable ‘smart paper sensor’ for food packaging is being developed that can monitor potential food spoilage. It includes looking at advancing the food spoilage detection by utilizing selected bioassays. The market for processed food is very global and increasing. The methods available for detection of food spoilage these days are time consuming or expensive like PCR, nucleic acid assays, impedance tests etc. Hence packaging industry is looking for strategies that actively contribute to an early and less time consuming ways to detect the foul foods. Enzymes are molecules that make possible specific chemical reactions without being consumed in the process and are a key component in various bioassays for food safety detection. The main challenge in these applications is enzyme immobilization on the sensor media. The analysis of fossilised diatoms typically shows 80% to 90% silica which are to be used as sensor media. A successful immobilization also provides a better environment for the enzyme activity. In our research with sensor paper, we are taking our first steps in experimenting immobilization of enzymes to detect harmful bacteria in food. Enzymes are covalently immobilised on the diatoms. β-galactosidase is used as a model enzyme. β-galactosidase can be used to detect lactose in milk or whey. It will be covalently immobilised on the diatoms and the activity of the immobilised enzyme will be compared to free enzyme.