PKC BIOSENSOR: AN IMPEDANCE-BASED AFFINITY DETECTION PLATFORM
Electrochemical impedance spectroscopy (EIS) is a sensitive technique well-suited to investigate and characterize biological events occurring at the interface of conductive surfaces and liquid solutions [1-6], such as bacterial growth media, cerebrospinal fluid (CSF), serum, and plasma. EIS combines high sensitivity, cost-effectiveness, labeling-free, rapid response, and real-time monitoring of samples, in sharp contrast to established technologies such as PCR and ELISA.
Our detection system implements interdigitated micro-electrodes to measure the impedance of the solution containing the test sample. The surface of the electrode is coated with receptors known to have high specificity towards the analyte of interest, such as pathogenic bacteria or vascular endothelial growth factor (VEGF). When the sensor is exposed to the target analyte, the analyte is captured by the immobilized receptors causing a noticeable change in the measured impedance. The change in impedance directly correlates to the amount of target analyte bound to the sensor surface, allowing our system to perform both qualitative and quantitative analysis.
This detection system will have applications monitoring:
Pathogenic bacteria activity in foods and beverages to ensure their safety.
Fluctuating levels of VEGF proteins in the CSF of brain cancer patients to optimize the amount of chemotherapeutic drug(s) delivered to a tumor area.
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