针对于白蛋白的新型核酸适配体的筛选与鉴定

目的研发能特异结合白蛋白的DNA核酸适配体,为去除实验样品中的白蛋白提供新型技术手段。方法体外合成全长为59个碱基并含有21个随机寡核苷酸的单链DNA文库,以白蛋白为靶标,利用指数富集的配体系统进化技术(SELEX),从单链DNA文库中筛选能特异结合白蛋白的核酸适配体;用流式细胞计量术来检测核酸适配体的富集程度、适配体与白蛋白的结合特性;用MFold软件预测其二级结构。结果经过多轮筛选得到了能特异识别白蛋白的DNA核酸适配体A6,其Kd值为77.4 nmol/L,且基本不结合卵清蛋白、免疫球蛋白Ig G等对照蛋白。结论针对于白蛋白的DNA核酸适配体A6能选择性识别白蛋白,在去除实验样品中的白蛋白方面具有应用潜能。

Screening and identification of a novel DNA aptamer against albumin

Objective To develop an albumin aptamer that may potentially serve as a selective ligand for albumin removal from experimental samples.Methods A single-stranded 59nt DNA library that contains 21 random oligo nucleotides was synthesized in vitro.An albumin aptamer A6 was developed by SELEX technique using bovine serum albumin (BSA) as target.The enrichment of aptamer and evaluation of its binding properties were monitored by flow cytometry.The secondary structure of A6 was predicted by MFord software.Results The aptamer A6 strongly bound to BSA with a Kd of 77.4 nmol/L,and had minimal cross reactivity with control proteins including ovalbu min,IgG,and trypsin.Conclusions Aptamer A6 may be a potential tool in albumin removal.