Interaction of triethylamine (TEA) with cationic proflavin (PF+) in homogeneous and micellar media is studied using absorption spectroscopy, steady-state as well as time-resolved fluorescence spectroscopy and laser flash photolysis in conjunction with an external magnetic field. The two prime phenomena that have been highlighted in this study are photoinduced electron transfer (PET) and ground-state complex formation. This study shows that it is the medium which determines the reaction pathways to be followed. Magnetic field effect (MFE) helps to elucidate the reaction mechanism involved and this work also highlights the distance dependence factor associated with MFE. (C) 2009 Elsevier B. V. All rights reserved.