CdSe@CdS　core　shell　quantum　dotsQDswere　used　as　luminescent　materials　which　was　combined　with　chitosanCSand　graphitic　carbon　nitridegC3　N4　to　synthesize　composite　of　CdSe@CdS/CS/gC3　N4　.　The　composite　was　modified　onto　the　surface　of　a　glassy　carbon　electrodeGCE.　Then　the　complementary　strand　cDNAof　the　aptamerAptwas　connected　to　QDs　by　chemical　reaction.　MeanwhileApt　was　hybridized　with　cDNA　and　modified　to　the　electrode　surface.　Horseradish　peroxidaseHRPwas　immobilized　on　the　surface　of　the　modified　electrode　and　an　electrochemical　luminescenceECLaptamer　sensor　for　kanamycinKanawas　constructed.　The　detection　of　Kana　was　realized　by　the　biocatalytic　precipitation　BCP　procedure.　In　the　absence　of　Kana　and　in　the　presence　of　H2　O2　HRP　modified　on　the　electrode　can　catalyze　and　oxidize　4-chloro-1　naphthol4-CNand　non-conductive　benzo-4-chlorhexadienone　precipitated　on　the　electrode　surfacewhich　caused　the　obvious　decrease　of　electrochemiluminescence　signal.　In　the　presence　of　Kanait　will　specifically　bind　to　Apt　and　cause　partial　unscrewing　of　dsDNAleading　to　partial　shedding　of　HRP　from　the　electrode　surfaceweakening　of　BCP　reactionand　increasing　of　ECL　signalthereby　realizing　the　specific　detection　of　the　target　substance.　The　difference　ΔII-I0　between　the　ECL　intensityIof　the　Apt　sensor　in　Kana　solution　and　the　ECL　intensityI0　of　the　sensor　in　blank　solution　was　calculated　as　the　response　signal.　The　results　showed　that　there　was　a　good　linear　relationship　between　ΔI　and　the　logarithm　of　Kana　concentration　in　the　range　of　1.0×10-8　1.0×10-4　g/Land　the　detection　limit　was　5　ng/L.　The　sensor　possesses　a　good　application　prospect　in　determination　of　Kana　in　real　samples.　©　2023,　Youke　Publishing　Co.,Ltd.　All　rights　reserved.