Diffusional studies for gold crosslinked collagen coated membranes for intravascular biosensors [abstract]

Abstract

According to the American Heart Association, approximately 865,000 Americans every year will experience recurrent or new myocardial infarctions. If a patient is not treated promptly, a myocardial infarction can be fatal. Currently a biosensor is being developed that can detect troponin-T, an enzyme that is released by cells when tissue necrosis occurs and is a precursor to myocardial infarction. Because this cardiac enzyme biosensor is a foreign object to the human body, a biocompatible coating surrounding the sensor is being developed to placate the foreign body response. We are performing diffusional studies to ensure that troponin-T can diffuse through this biocompatible coating. Two types of collagen coatings are being investigated: 1) collagen I fibers adsorbed onto a dialysis membrane and 2) collagen I fibers crosslinked with gold nanoparticles adsorbed onto a dialysis membrane. The diffusion system consists of a perfusion chamber connected to a 12-roller peristaltic pump with the coating placed between the upper and lower chambers of the perfusion device. The two different coatings are then tested. To perform each test, a known concentration of α-lactalbumin (an inexpensive substitute for troponin-T) labeled with fluoroscein is pumped through the upper chamber of the perfusion device while samples are taken from the lower chamber and are scanned with a fluorometer to measure the amount of α-lactalbumin that has diffused through the coating. Preliminary experiments show that α-lactalbumin is diffusing through the coatings.