Simultaneous voltammetric determination of Adrenaline and Tyrosine in real samples by neodymium oxide nanoparticles grafted graphene

Nd₂O₃ nanoparticle grafted graphene nanocomposite (NOGG) was synthesized by sonochemical treatment of an ethanolic dispersion of Nd₂O₃ nanoparticle and graphene. All the synthesized materials were characterized by XRD, FESEM, TEM, and BET. The NOGG has a high specific surface area (272 m²g^-1) with narrowly distributed pores with diameter centered at 2.8, 6.0 and 7.50 nm. A composite paste electrode of 1:1 (w/w) NOGG and graphite was showed better electrochemical properties. The NOGG/GP electrode showed all around better electrocatalytic activity towards Adrenaline (AD) and Tyrosine (TY) than TRG/GP and bare GP electrode. According to cyclic voltammograms, AD and TY oxidized irreversibly through adsorption control process. DPV peak currents were measured at 378 ± 15 mV and 787 ± 15 mV for determination AD and TY respectively using the NOGG/GP electrode as the peak intensities were highest at those potentials. Under the optimized experimental condition, the determination ranges for AD and TY showed two linear ranges, those were 0.1-5-130 μM and 0.1-3-120 μM, respectively. A detection limit of AD and TY was measured (m-LOD) to be 50 nM and 40 nM, respectively. The modified electrode was reproducible, selective, highly sensitive and also employed for analysis of AD and TY in biological and pharmaceutical samples with excellent recovery.