In this research, we describe application of nonmaterial such as multiwall carbon nanotubes (MWCNTs) and nanoparticles (such as TiO 2 ) for modification of carbon paste electrode (as a working electrode) in the presence ionic liquid or organic/inorganic mediators. In continues, we study electrochemical behavior of these modified electrodes in aqueous buffer solution using cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS). We used these modified electrodes for determination of drug and other biological compounds in two sections. In the first section, we describe determination of thioguanine, folic acid, captopril, hydrochlorothiazide, isoproterenol, cysteamine, tryptophan, mercaptopurine, uric acid, penicillamine, actylcysteine, acetaminophen and ascorbic acid at a surface of multiwall carbon nanotubes paste electrode modified with some suitable mediator using electrocatalytic mechanism. In the second section, we study application of ionic liquid (IL) modified electrode in the presence of multiwall carbon nanotubes as a sensor for determination of isoproterenol and morphine. Some sensitive techniques such as differential pulse voltammetry, square wave voltammetry and linear sweep voltammetry were used for sensitive determination of above compounds alone and simultaneously. All of these modified electrodes were successfully applied to the determination of biological compounds in real samples such as drug, serum and urine samples.
