We herein report a simple, low cost and green preparation of nanowires of (anthraquinone-2-carboxylic acid/amino functionalized) multiwalled carbon nanotubes (HOOC-2-AQ/AMWCNTs) which has been further employed for the development of highly sensitive oxygen sensor. The prepared composite has been characterized by TEM and electrochemical studies. The glassy carbon electrode modified with composite shows an irreversible and good electrocatalytic activity for the reduction of oxygen. The reduction potential of the oxygen was shifted 460 mV towards the positive potential with this modified electrode as compared to bare glassy carbon electrode. The prepared material was stable with no leaching observed of the mediator. A linear response range of 0.2-6.8 mg L-1, with a sensitivity of 5.0 mu A L mg(-1) and a detection limit of 0.02 mg L-1 were obtained with this sensor. (C) 2012 Elsevier Ltd. All rights reserved.