Improved in Vivo Performance of Amperometric Oxygen (PO2) Sensing Catheters via Electrochemical Nitric Oxide Generation/Release
journal contributionposted on 18.08.2015 by Hang Ren, Megan A. Coughlin, Terry C. Major, Salvatore Aiello, Alvaro Rojas Pena, Robert H. Bartlett, Mark E. Meyerhoff
Any type of content formally published in an academic journal, usually following a peer-review process.
A novel electrochemically controlled release method for nitric oxide (NO) (based on electrochemical reduction of nitrite ions) is combined with an amperometric oxygen sensor within a dual lumen catheter configuration for the continuous in vivo sensing of the partial pressure of oxygen (PO2) in blood. The on-demand electrochemical NO generation/release method is shown to be fully compatible with amperometric PO2 sensing. The performance of the sensors is evaluated in rabbit veins and pig arteries for 7 and 21 h, respectively. Overall, the NO releasing sensors measure both venous and arterial PO2 values more accurately with an average deviation of −2 ± 11% and good correlation (R2 = 0.97) with in vitro blood measurements, whereas the corresponding control sensors without NO release show an average deviation of −31 ± 28% and poor correlation (R2 = 0.43) at time points >4 h after implantation in veins and >6 h in arteries. The NO releasing sensors induce less thrombus formation on the catheter surface in both veins and arteries (p < 0.05). This electrochemical NO generation/release method could offer a new and attractive means to improve the biocompatibility and performance of implantable chemical sensors.