One of important problems in the diagnostic and treatment of the patient’s states is operative evaluation of a type and amount of various neuropeptides secreted into the blood in human organisms. Due to similar structures and molecular weight of neuropeptides, their identification and individual evaluation is very complicated and not always consistent. For example, such substances as Oxytocin and Argenine-Vasopressin act differently on the human body, however they are look similar. The main purpose of the present work is to create a non-destructive sensor enabling operatively differentiate and evaluate the quantity of various neuropeptides existing in the human fluids such as sweat, saliva or blood. Through the experimental and theoretical efforts, it was found that the proposed goal may be solved using nanostructured semiconductor sensor producing the plasmon-polaritons in the near ultra-violet range. The frequency and intensity of generated plasmons are affected by material composition of the studied analyte.