<title>Spectroscopic investigation of the nicotinic acetylcholine receptor for application in medical diagnosis</title>

Native vesicles containing the nicotinic acetylcholine receptor (nAChR) prepared from the electric organ of the ray Torpedo marmorata were used to obtain fluorescence signal sin dependence of different concentrations of the local anesthetics procaine. Nonlinear concentration dependent spectral changes are found using ethidium bromide as a fluorescence marker. Structural changes are found for the proteins including the nAChR in the vesicles during immobilization onto surfaces such as IR transparent germanium (GE) crystal, Ge crystal coated with silver (Ag) cluster to use the SEIRA effect and/or crystals covered with a lipid subphase. A comparison between Ge and Ge coated with Ag (Ge/Ag) clus…