Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Electrodes that were chemically modified by reduced graphene oxide have properties that dependent on the synergy between the level of restoration of the sp(2) structure and the functional groups. Because of this, the challenge in the chemistry of graphene is how to reach the equilibrium between electrical conductivity and specific interactions between the surface and molecular targets and how to tune it. In this work, a simple and effective method to modulate the electrochemical properties of reduced graphene oxide by photoreduction using UV-light emitting diodes is reported. Moreover, we also succeeded in controlling the percentage of oxygenated groups and electrical conductivity, which reflects directly on the electrochemical behavior. The influence of the reduction extent is explored using photochemically reduced graphene oxide generated as a potential sensor for trace detection of dopamine, proving the efficiency and importance of this tunable reduction approach for device-design development, mainly for the synergistic effect among electrical conductivity, pi-interaction and the amount of oxygenate functional groups.1611681175CAPESINCTCNPq [459923/2014-5]Sao Paulo Research Foundation, FAPESP [2012/12773-1, 2013/22127-2]Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)