CdSe　quantum　dots　(QDs)　were　prepared　at　room　temperature　by　E-beam　irradiation　of　the　solution,　using　ethylene　diamine　tetraacetic　acid　as　stabilizer.　Silica-coated　CdSe　QDs　were　made　in　water-in-oil　microemulsion,　while　amino　groups　were　introduced　synchronously　onto　the　nanoparticles　by　copolymerization　of　3-aminopropyl-trimethoxysilane　and　tetraethyl　orthosilicate.　The　results　of　TEM　imaging,　fluorescent　spectroscopy　and　photostability　tests　show　that　the　QDs　are　of　uniform　spherical　size　(200　+/-　8　nm),　monodispersity,　and　high　fluorescence　and　photostability.