【摘要】 本文建立了一种高选择性的、以纳米金为探针结合适配体识别来检测卡那霉素的分光光度方法。采用溶剂热合成法,通过氯金酸和柠檬酸三钠制备了纳米金;基于纳米金变色直接检测了卡那霉素,其间考查了多种不同因素的影响,同时选择土霉素、氨苄西林、硫酸新霉素、四环素和氯霉素等五种抗生素开展选择性实验,结果表明仅依靠纳米金变色直接检测卡那霉素,其选择性具有一定的局限性。结合卡那霉素核酸适配体,当卡那霉素存在时,适配体和卡那霉素结合,加入一定浓度的NaCl会破坏纳米金溶液的稳定性,使纳米金发生聚集,进而导致溶液由红色变为蓝色。若不存在卡那霉素,溶液依然保持红色。经考察,在0.1mol/LNaCl存在下的条件下,该方法展现出良好的线性和选择性,线性范围处于4.0～18nmol/L之间,线性方程为y=44.396x+0.3392,相关系数R~2=0.9934,检出限为3S/k=3.44nmol/L。更多还原

【Abstract】 A highly selective spectrophotometric method for detecting kanamycin by using gold nanoparticles as probes combined with aptamer recognition was established. Gold nanoparticles were prepared by chloroauric acid and trisodium citrate using the solvothermal synthesis method. Kanamycin was directly detected based on the color change of gold nanoparticles. During this process,the influence of many different factors was investigated. Meanwhile,five antibiotics such as oxytetracycline,ampicillin,neomycin sulfate,tetracycline and chloramphenicol were selected for selectivity experiments. The results showed that the selectivity of directly detecting kanamycin only relying on the color change of gold nanoparticles had certain limitations. Combined with the kanamycin nucleic acid aptamer,when kanamycin was present,the aptamer was combined with kanamycin. Adding a certain concentration of NaCl would destroy the stability of the gold nanoparticle solution,causing the gold nanoparticles to aggregate,and then leading the solution to change from red to blue. If kanamycin was not present,the solution remained red. After investigation,under the condition of 0. 1mol/L NaCl,this method showed good linearity and selectivity. The linear range was between 4. 0-18 nmol/L,the linear equation was y= 44. 396x+0. 3392,the correlation coefficient R~2= 0. 9934,and the detection limit was 3S/k= 3. 44 nmol/L.更多还原