In this paper, a green and facile approach is presented for the synthesis of carbon nanoparticles (CNPs) by a soot based method using the natural precursor castor oil. The synthesized carbon nanoparticles were used in the detection and electrochemistry of dopamine (DA), ascorbic acid (AA) and uric acid (UA). The synthesized product is characterized by Powdered X-ray diffraction (PXRD), UV-visible absorption spectroscopy, Scanning electron microscopy (SEM), Energy dispersive X-ray spectrum (EDS) and Infrared spectroscopy (IR). CNPs modified carbon paste electrodes provided a detection limit for DA 1.2 x 10(-7) M. The cyclic voltammetric response of DA at a carbon nanoparticles modified carbon paste electrode was excellent when compared to a bare carbon paste electrode. The effect of scan rate, concentration, and pH effects on the voltammogram of DA were studied as well as the effects of the surfactants sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB) and Triton X-100 (TX-100). (C) 2014 Elsevier B.V. All rights reserved.