P1.01 - An optical sensor for studying hemocompatibility of biomaterials in a flow system

13. Dresdner Sensor-Symposium 2017
2017-12-04 - 2017-12-06
Hotel Elbflorenz, Dresden
P1. Biomedizinische Sensorik
J. Hutterer, G. Gauglitz - Eberhard Karls University, Tübingen/D
162 - 166


When implants get into contact with body fluids such as blood, lymph or saliva, proteins start to adhere to their surface within milliseconds. The amount, type and possible conformational changes of the adhering proteins initiate various processes, such as platelet accumulation, activation of immunological cascades, formation of foreign body giant cells or apoptosis of adherent cells [1]. These unintended interactions of a foreign material with the human body can inter alia - result in implant failure.
The here presented sensor has been developed to be particularly suitable for testing hemocompatibility. The formation of a protein film that develops on the sensor surface is recorded using reflectometric interference spectroscopy [2]. This label-free and temperature independent technique monitors the change in optical thickness – the product of physical thickness and the reflective index – caused by association or disassociation processes. By using a semi-steady flow of the protein solution across the sensor surface, the fluid dynamic properties of blood vessels are mimicked. The influence on the formation of protein films of different commonly used materials in cardio-vascular implants, such as polyethylene glycol and polyurethane, and furthermore a biomimicking phospholipid membrane surface was evaluated.
In the future, the here presented method can be extended to adherence analysis of further blood components, such as platelets, erythrocytes and lymphocytes. By testing the adherence of these cellular blood components individually or in combination with other blood components, a more complete picture of the body response to cardio-vascular implant surfaces could be achieved.