School of Chinese Medicine
Comparison of the methods for generating single-stranded DNA in SELEX
The generation of single-stranded DNA (ssDNA) from double-stranded PCR products is an essential step in the selection of aptamers by systematic evolution of ligands by exponential enrichment (SELEX). Magnetic separation with streptavidin-coated beads is always the most commonly used method. Recently, two size separation methods derived from unequal primers with chemical or structural modification were designed in SELEX. In this report, we made a comparison between magnetic separation and the two size separation methods for generation of ssDNA from double-stranded PCR products. Our results showed that all the methods produced ssDNA of good purity. Compared to the magnetic separation, size separation derived from unequal primers with chemical modification achieved an almost equivalent recovery rate of ssDNA, whereas size separation derived from unequal primers with structural modification showed a lower recovery rate of ssDNA. Considering the low cost, size separation derived from unequal primers with chemical modification could be a satisfactory alternative to the classic magnetic separation for the generation of ssDNA in SELEX.
Source Publication Title
Royal Society of Chemistry
This journal is © The Royal Society of Chemistry 2015
This study was supported by the Ministry of Science and Technology of China (2013ZX09301307), the Hong Kong General Research Fund (HKBU479111, HKBU478312, HKBU12102914 and HKBU261113), the Natural Science Foundation Council (81228013), the Research Grants Council & Natural Science Foundation Council (N_HKBU435/12), the Interdisciplinary Research Matching Scheme (IRMS) of Hong Kong Baptist University (RC-IRMS/12-13/02 and RC-IRMS/13- 14/02), the Hong Kong Baptist University Strategic Development Fund (SDF) (SDF13-1209-P01), the Hong Kong Research Grants Council (RGC) Early Career Scheme (ECS) (489213) and the China Academy of Chinese Medical Sciences (Z0252 and Z0293).
Link to Publisher's Edition
Liang, Chao, Defang Li, Guangxian Zhang, Hui Li, Ningsheng Shao, Zicai Liang, Lingqiang Zhang, Aiping Lu, and Ge Zhang. "Comparison of the methods for generating single-stranded DNA in SELEX." Analyst 140.10 (2015): 3439-3444.