Monday, 10 October 2022
G. Buckey, O. Owens, and D. E. Cliffel (Vanderbilt University)
Preterm birth (PTB) is the top cause of death in newborns and the second leading cause of death in children under the age of five. Certain cytokines, like interleukin-6 (IL-6), and matrix metalloproteinases (MMPs) are known to facilitate the degradation of the fetal membrane, but the mechanisms that result in fetal membrane rupture under both normal and pathological conditions are largely unknown. Our fetal membrane-on-a-chip model will allow us to investigate the conditions and mechanisms that precede fetal membrane rupture. Our enzymatic electrochemical detection platform allows us to detect biosignatures from the fetal membrane by measuring analyte concentration changes such as glucose utilization, lactate production, and oxygen consumption. Addition of electrochemical sensors for cytokine and MMPs to the detection platform will provide further insight into the mechanisms underlying PTB by offering low-level protein biomarker quantification.
We are currently fabricating and optimizing electrochemical immunoassays for the detection of IL-6 and MMP-3 to leverage the advantages of electrochemical techniques in studying preterm births. The current protein assay design utilizes the enzyme alkaline phosphatase attached to the target protein. When introducing the substrate p-aminophenyl phosphate (PAPP) to the system, it is enzymatically converted to p-aminophenol (PAP). Upon oxidation, PAP is converted to p-quinone (PQI). We are currently studying the electrochemical behavior of PAP/PQI for application in immunoassays. We are investigating the use of different electrochemical techniques for PAP oxidation to PQI including cyclic voltammetry, square wave voltammetry, differential pulse voltammetry, and normal pulse voltammetry to see how the technique affects the reproducibility of assay measurements.
