Non-invasive Point-of-Care Device To Diagnose Acute Mesenteric Ischemia

Inadequate blood supply to the intestine can lead to acute mesenteric ischemia (AMI), with a mortality rate ranging from 60% to 90%. This high mortality rate is partially due to late detection and the lack of efficient early diagnostic tests. There is an urgent need for a point-of-care tool for immediate bedside diagnosis. Here we present for the first time a rapid and non-invasive electrochemical biosensor device based on non-faradic impedance spectroscopy to detect intestinal fatty-acid binding protein (I-FABP) as an indication of AMI. The electrochemical biosensors consist of gold interdigitated electrodes that were fabricated using photolithographic techniques on top of silicon dioxide substrates. The electrode surfaces were functionalized with an I-FABP capture antibody (CAnB) to entice the target protein, while gold nanoparticles (GNPs) functionalized with detection antibodies (DAnB-GNPs) were utilized as a novel mechanism to enhance the detection signal. Quantification of the I-FABP concentration in the medium depended on its attachment to CAnB and DAnB-GNPs in a sandwich manner, where the latter boosts the impedance signal through its binding to the I-FABP. This non-invasive non-faradic electric biosensor device demonstrates the potential for bench-to-bedside translation with the goal of decreasing morbidity and mortality from AMI.