Kanamycin is an aminoglycoside antibiotic used increasingly in human and veterinary medicine. However, kanamycin residues in food can cause serious side effects, Here we reported the preparation of polyclonal antibody...Kanamycin is an aminoglycoside antibiotic used increasingly in human and veterinary medicine. However, kanamycin residues in food can cause serious side effects, Here we reported the preparation of polyclonal antibody and the development of an indirect competitive biotin-streptavidin-amplified-based enzyme-linked immunosorbent assay（BA-ELISA） that can sensitively and specifically detect kanamycin residues in milk and honey. The immtmogen and coating antigen were synthesized by covalently linking kanamycin to carrier proteins using the carbodiimide method. The anti-kanamycin polyclonal antibodies were obtained from immunized rabbits. The key assay parameters were investigated and optimized. The results show that under optimum conditions, the limit of detection for kanamycin is 0.07 ng/mL and the ICs0 is 6.48 ng/mL. Cross-reactivity values of the antibody with four kanamycin analogues are all 〈1%. Trace amounts of kanamycin in milk and honey samples can be detected by this novel BA-ELISA method successfully with satisfactory recoveries of 91.0%-103.3%. The developed protocol was also validated against liquid chromatography-mass spectrometry, returning a significant correlation. These results indicate that BA-ELISA is a viable option for monitoring kanamycin residues in milk and honey.展开更多
核酸适配体是人工合成的短链核酸,作为分子识别元件,能够与各类靶标物质高特异性、高亲和力的结合,分为单链DNA和RNA两种类型。其中单链DNA适配体由于其稳定性比RNA适配体更好而更受欢迎,因此得到广泛应用。核酸适配体筛选通常是通过配...核酸适配体是人工合成的短链核酸,作为分子识别元件,能够与各类靶标物质高特异性、高亲和力的结合,分为单链DNA和RNA两种类型。其中单链DNA适配体由于其稳定性比RNA适配体更好而更受欢迎,因此得到广泛应用。核酸适配体筛选通常是通过配体指数富集系统进化技术(systematic evolution of ligands by exponential enrichment,SELEX)实现的,筛选能否成功在很大程度上取决于其最关键的单链制备步骤,即将双链DNA转化为相应的单链DNA。目前,存在许多方法可以制备单链DNA,包括热变性法、生物素-链霉亲和素亲和分离法、变性胶电泳分离法、核酸外切酶消化法、不对称聚合酶链式反应(polymerase chain reaction,PCR)法等。本文在总结文献报道的基础上,具体阐述了各种单链DNA制备方法的原理、优缺点及近5年的应用情况,并对这些单链DNA制备方法进行了比较和展望,以期能为成功筛选各类靶标的核酸适配体提供参考。展开更多
基金Supported by the National Natural Science Foundation of China（No.21675008）, the Natural Science Foundation of Beijing, China（No.2132048） and the Fundamental Research Funds for the Central Universities, China（No.JDl 516）.
文摘Kanamycin is an aminoglycoside antibiotic used increasingly in human and veterinary medicine. However, kanamycin residues in food can cause serious side effects, Here we reported the preparation of polyclonal antibody and the development of an indirect competitive biotin-streptavidin-amplified-based enzyme-linked immunosorbent assay（BA-ELISA） that can sensitively and specifically detect kanamycin residues in milk and honey. The immtmogen and coating antigen were synthesized by covalently linking kanamycin to carrier proteins using the carbodiimide method. The anti-kanamycin polyclonal antibodies were obtained from immunized rabbits. The key assay parameters were investigated and optimized. The results show that under optimum conditions, the limit of detection for kanamycin is 0.07 ng/mL and the ICs0 is 6.48 ng/mL. Cross-reactivity values of the antibody with four kanamycin analogues are all 〈1%. Trace amounts of kanamycin in milk and honey samples can be detected by this novel BA-ELISA method successfully with satisfactory recoveries of 91.0%-103.3%. The developed protocol was also validated against liquid chromatography-mass spectrometry, returning a significant correlation. These results indicate that BA-ELISA is a viable option for monitoring kanamycin residues in milk and honey.
文摘核酸适配体是人工合成的短链核酸,作为分子识别元件,能够与各类靶标物质高特异性、高亲和力的结合,分为单链DNA和RNA两种类型。其中单链DNA适配体由于其稳定性比RNA适配体更好而更受欢迎,因此得到广泛应用。核酸适配体筛选通常是通过配体指数富集系统进化技术(systematic evolution of ligands by exponential enrichment,SELEX)实现的,筛选能否成功在很大程度上取决于其最关键的单链制备步骤,即将双链DNA转化为相应的单链DNA。目前,存在许多方法可以制备单链DNA,包括热变性法、生物素-链霉亲和素亲和分离法、变性胶电泳分离法、核酸外切酶消化法、不对称聚合酶链式反应(polymerase chain reaction,PCR)法等。本文在总结文献报道的基础上,具体阐述了各种单链DNA制备方法的原理、优缺点及近5年的应用情况,并对这些单链DNA制备方法进行了比较和展望,以期能为成功筛选各类靶标的核酸适配体提供参考。
