Measuring Contact Stress with 19F-NMR Spectroscopy
Increased static contact stress is associated with tissue damage in vivo and in vitro. It could be caused by edema (for example, in normal hydrocephalus) or a growing tumor which displaces surrounding tissue. Measurement of contact stress is inherently invasive, however, it can be less traumatic with a sensor having no wires or leads. One goal of this chapter is to propose that NMR spectroscopy can perform the function of a telemetry system provided that an in-dwelling transducer can convert the desired physical quantity (such as applied stress) to an NMR detectable chemical change. Previously, it was observed that compressing polyelectrolyte gels could cause a redistribution of mobile ions that is measurable with NMR spectroscopy . In the sensor described below, the applied stress is inferred from a non-invasive 19F-NMR spectroscopic measurement of pH.
KeywordsApplied Stress Contact Stress Dissociation State Hydrolyze Polyacrylamide External Bath
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