Fig_1.tif (668.6 kB)
A comparison between conventional qPCR and touchdown qPCR (TqPCR) in quantitatively amplifying a target sequence in pUC19.
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posted on 2015-07-14, 02:52 authored by Qian Zhang, Jing Wang, Fang Deng, Zhengjian Yan, Yinglin Xia, Zhongliang Wang, Jixing Ye, Youlin Deng, Zhonglin Zhang, Min Qiao, Ruifang Li, Sahitya K. Denduluri, Qiang Wei, Lianggong Zhao, Shun Lu, Xin Wang, Shengli Tang, Hao Liu, Hue H. Luu, Rex C. Haydon, Tong-Chuan He, Li Jiang(A) TqPCR expands the detection limit of DNA levels. PCR primers specific for pUC19 plasmid were used to amplify serially diluted pUC19 DNA, and the themocycling programs were carried out using a DNAEngine OPTICON II unit (Bio-Rad). PCR amplification curves (e.g., SYBR Green fluorescence history vs. cycle numbers) were plotted for conventional qPCR (a) and TqPCR(b). (B) Cq value comparison between conventional qPCR and TqPCR reactions. Mean Cq values were obtained for both qPCR and TqPCR using the same dilution series of pUC19 DNA (a). The standard curves were established with scatter plot (b). Triplicate was performed for each assay condition. “**”, indicating the Cq difference between qPCR and TqPCR groups is significant with p<0.001.
