Title : Nanocomposite-based DNA-biosensor to detect animal species in food
Abstract:
Food adulteration is a serious concern all over the world as it has a significant impact on customers' health, religion, lifestyle, and economy. In the previous decade, several food fraud instances have emerged, emphasising the necessity of food authenticity. Therefore, the detection of animal species in food products is an important issue that should be addressed in order to promote fair trade and allow customers to make informed decisions. In addition, species identification is directly linked to food safety monitoring. Until now, polymerase chain reaction (PCR) based methods are widely used and popular methods for detecting animal species. However, PCR-based techniques are laboratory-oriented, laborious, time-consuming and need skilled personnel to perform the test. On the other hand, DNA biosensors-based approaches are field-based, rapid, sensitive, low cost, and there is no need for skilled personnel. Therefore, the demand for DNA biosensors-based methods is increasing day by day. We developed electrochemical DNA biosensors for the detection of pork DNA in food products using gold nanoparticles (AuNPs) and graphene (Gr) composite modified screen-printed carbon electrode (SPCE) as a detection platform. To hybridize the target DNA, the thiol modified DNA probes were immobilized on modified SPCE. The nanocomposite was characterized using UV-Vis, Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM) and energy dispersive X-ray (EDX) methods. The cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) were carried out to characterize the modified electrodes. The developed biosensor showed high specificity toward target DNA and could discriminate pork DNA from other species. The system was highly sensitive and able to detect up to 0.85×10-12 M.
Audience take-away:
- How to modify screen-printed carbon electrode (SPCE) with nanocomposite.
- How to design the specific probe for DNA biosensors.
- How to develop DNA biosensors for the authentication of food products.
