Development of a Multifunctional Biosensing Platform with Applications Across Various Consumer Markets and Industries

The purpose of this work is to develop a point-of-use affinity-based biosensing platform capable of detecting biomarkers across complex matrices – ranging in electrolyte and macromolecule composition – with applications in consumer industries and regulatory marketspaces. This work focuses on the sensor and hardware development process to promote highly sensitive biomarker detection. First, this work explored how to enhance sensor performance while maintaining a compact design. The ideal placement of the electrodes was determined to stabilize the biosensor's baseline electrochemical characteristics. Additionally, the signal response was monitored with varying input signals and electrolyte constituency. Next, interactions between the sensor and target biomarker were explored in the presence of complex matrices. Both capacitive and resistive responses were recorded to identify the best detection modality for each biomarker/matrix combination. Last, the sensor performance was evaluated to predict the presence of the biomarker in each complex matrix. A limit-of-detection was identified for each biomarker/matrix combination, and a model was erected to accurately predict the presence of the biomarker. The sensor platform demonstrated stable faradaic detection of GMO proteins in plant and food extracts; non-faradaic detection of two strains of wheat viruses in reconstituted plant samples; non-faradaic detection of antibiotics in meat; as well as non-faradaic detection of a psychoactive marijuana compound within human saliva. This platform displayed excellent translatability when exploring numerous biomarkers in an array of complex matrices by leveraging a more intuitive understanding of the electrode-electrolyte interface and defining a systematic approach for evaluating key optimization parameters of electrochemical biosensors.