Schwingquarze als Hämostase-Sensoren (English shop)

Eine neue Methode zur hämostaseologischen Diagnostik in Vollblut

Preview

Table of Contents, Datei (58 KB)
Preface, Datei (85 KB)

A finely balanced haemostatic equilibrium is essential for many physiological processes. Disturbances of this equilibrium can cause considerable complications and may even have fatal consequences. Comprehensive and rapid monitoring of the entire haemostatic system for the early detection and characterisation of impending disturbances is therefore imperative, particularly in this field. The aim of the present dissertation was the development of haemostaseological tests using acoustic sensors. For this purpose, piezoelectric quartz crystals with a resonance frequency of 10 MHz were employed to investigate coagulation, fibrinolysis and platelet function in whole blood.

For the respective tests, a wide variety of quartz crystal coatings were realised, characterised and examined for their suitability for the individual test. In addition to hydrophilic coatings with polyethylene glycols and hydrophobic polymer coatings with polystyrene or polyethylene, covalently immobilised protein surfaces were also used. On polyethylene-coated quartz crystals it was possible for the first time to determine the clotting times of modified Quick tests in whole blood in very good agreement with coagulometry, the medical standard method. Moreover, on surfaces coated in this way, hyperfibrinolytic dissolution processes of blood clots could be detected in real time, the results of quartz crystal sensing again correlating very well with those of established methods. Investigations into the aggregation and adhesion capacity of intact platelets could be carried out on the uncoated gold surface of the quartz crystal electrode, on polystyrene-coated surfaces and on surfaces with covalently bound fibrinogen, in very good agreement with the medical routine method. Likewise, the damaging effect of acetylsalicylic acid on platelet aggregation could be demonstrated by quartz crystal sensing on each of these three sensor coatings. All haemostaseological tests established in this work could be successfully performed, by way of example, on the microfluidic chip with integrated quartz crystal sensor developed in the course of the project.

The enormous potential of quartz crystal sensing in the field of haemostaseological diagnostics becomes evident from the results achieved in this work. They provide the basis for addressing further interesting areas, such as the detection of individual coagulation factors or of fibrinogen degradation products.