A　nanometer-sized　titanic　substance,　titanate　nanotube,　was　synthesized　and　used　for　investigating　the　electrochemiluminescence　(ECL)　behaviors　of　lucigenin.　A　self-assembled　film　of　titanate　nanotube　was　formed　on　the　chitosan　modified　glassy　carbon　electrode　(GCE)　through　electrostatic　attraction.　Comparing　with　the　bare　GCE,　a　dramatically　enhanced　(more　than　50-fold)　and　more　stable　ECL　emission　of　lucigenin　could　be　achieved　on　the　proposed　TNTs/chitosan　composite　film-modified　GCE　under　the　cathodic　potential　scanning　mode.　Clonazepam　was　firstly　found　and　employed　as　the　coreactant　to　enhance　ECL　of　lucigenin.　Herein,　this　coreactant　ECL　system　was　investigated　on　the　proposed　ECL　platform　in　detail.　Under　the　optimum　conditions,　the　proposed　ECL　sensor　exhibited　a　linear　response　range　of　1.0　x　10(-8)-1.0　x　10(-4)　M　with　detection　limit　of　8.4　x　10(-9)　M　and　long-term　stability　for　clonazepam.　The　possible　mechanism　for　this　sensor　was　also　discussed.　(C)　2010　Elsevier　B.V.　All　rights　reserved.