Joeng Choon Bok, Niazi Javed H, Lee Su Jin, Gu Man Bock
College of Life Sciences and Biotechnology, Korea University, Anam-dong, Seongbuk-Gu, Seoul 136-701, South Korea.
Bioorg Med Chem. 2009 Aug 1;17(15):5380-7. doi: 10.1016/j.bmc.2009.06.044. Epub 2009 Jun 27.
A series of 56 ssDNA aptamer variants that bind to diclofenac (DCF) were selected from an initial pool of 2.4x10(14) ssDNA molecules by Flu-Mag SELEX process. Sequence analysis of these aptamer variants showed three major groups based on sequence similarity in their random N40 sequences. Out of these, four aptamers designated as D10/DA24, D22, D16, and D3 showed high affinity to DCF with K(d) values 100.64, 166.34, 148.73, and 42.7 nM, respectively. Secondary structures of these aptamers showed highly distinct features with typical stem and loop structures. Specificity tests with these four aptamer variants showed that D3 aptamer had higher specificity to DCF followed by 2-anilinophenylacetic acid (2APA), a structural analog of DCF. Whereas aptamers D16 and D22 showed higher specificity to 2APA compared to DCF as target used during selection process. Further, the D10/DA24 aptamer showed high affinity but no specificity to DCF. The DCF aptamers selected can be potential candidates for drug-delivery systems, specific detection of DCF and its derivatives in pharmaceutical preparations and contaminants.
通过荧光-磁珠指数富集配体系统进化技术（Flu-Mag SELEX），从2.4×10¹⁴个单链DNA分子的初始文库中筛选出了一系列56个与双氯芬酸（DCF）结合的单链DNA适配体变体。对这些适配体变体的序列分析表明，根据其随机N40序列的相似性可分为三大类。其中，命名为D10/DA24、D22、D16和D3的四个适配体对DCF表现出高亲和力，解离常数（K(d)）值分别为100.64、166.34、148.73和42.7 nM。这些适配体的二级结构具有高度独特的特征，呈现出典型的茎环结构。对这四个适配体变体进行的特异性测试表明，D3适配体对DCF的特异性更高，其次是DCF的结构类似物2-苯胺基苯乙酸（2APA）。而与筛选过程中用作靶标的DCF相比，适配体D16和D22对2APA表现出更高的特异性。此外，D10/DA24适配体对DCF表现出高亲和力，但无特异性。筛选出的DCF适配体可能是药物递送系统、药物制剂和污染物中DCF及其衍生物特异性检测的潜在候选物。
