Due　to　the　high　performance　of　glassy　carbon　in　the　aspects　of　mechanical　strength,　electrical　conductivity　and　high　corrosion　resistance,　etc.,　glassy　carbon　has　been　widely　used　in　the　electrochemistry.　A　new　form　of　glassy　carbon,　glassy　carbon　microsphere,　was　utilized　to　couple　with　ionic　liquid　in　preparing　a　new　electrochemiluminescent　platform　for　Ru(bpy)(3)Cl-2.　Room　temperature　ionic　liquid　has　been　proposed　to　be　very　interesting　and　efficient　pasting　binder　to　replace　the　non　conductive　organic　binders　for　the　fabrication　of　composite　paste　electrode.　Attributed　to　the　special　characteristics　of　glassy　carbon　microspheres　and　room　temperature　ionic　liquid　[N-octylpyridium　tetrafluoroborate　(OPFP)],　this　new　electrochemiluminescent　sensor　exhibited　excellent　electrochemiluminescent　performance　in　Ru(bpy)(3)(2+)　solution.　We　first　found　that　fentanyl　citrate　could　increase　the　ECL　of　Ru(bpy)(3)(2+),　hence　an　ECL　approach　was　developed　for　the　determination　of　fentanyl　citrate　based　on　this　glassy　carbon　microspheres　based　electrochemiluminescent　platform　with　high　sensitivity.　Under　the　optimized　conditions,　the　enhanced　electrochemiluminescent　intensity　versus　fentanyl　citrate　concentration　was　linear　in　the　range　of　1.0　x　10(-8)　to　1.0　x　10(-4)　mol　L-1　with　a　detection　limit　of　8.5　x　10(-9)　mol　L-1,　and　the　relative　standard　deviation　for　1.0　x　10(-6)　mol　L-1　fentanyl　citrate　was　1.90%　(n　=　10).　This　protocol　has　extended　the　application　scopes　of　glassy　carbon　material　and　promoted　the　application　of　glassy　carbon　microspheres　in　electroanalysis.　(C)　2009　Elsevier　B.V.　All　rights　reserved.