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(a) Changes in the relative fluorescence intensity for different molar ratios of the MB and the target DNA. (b) Comparison of the relative fluorescence intensities for the MB only, a noncomplementary target DNA with the MB, and the complementary target DNA with the MB.
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A rapid DNA analysis has been developed based on a fluorescence intensity change of a molecular beacon in a PDMS microfluidic channel. Recently, we reported a new analytical method of DNA hybridization involving a PDMS microfluidic sensor using fluorescence energy transfer (FRET). However, there are some limitations in its application to real DNA s...
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Context 1
... fluorescence intensities during the hybridization of non-complementary and complementary target DNA oligomers, compared with that of the MB alone, are shown in Fig. 5(b). Here, all of the fluorescence intensity data correspond to the values measured at position G. The fluorescence intensity for the complementary DNA was about 10-times stronger than that of the non-complementary DNA. This great difference is expected to allow the development of a superior probe for a quantitative evaluation of target ...
Context 2
... continual increase of the fluorescence intensity from A to G in Fig. 3(a) indicated that the hybridization reaction between the MB and complementary target DNA took a much longer time than simple mixing between the MB and non-complementary target DNA. As a result, the fluorescence intensity might have increased after position G for complementary target DNA at a flow rate of 10 μL/min. However, it was impossible to monitor the change in the fluorescence intensity over position G for the PDMS micofluidic channel used in this study. In order to find the equilibrium point for complete DNA hybridization, the hybridization reaction between MB and complementary target DNA was performed in a microtube at room temperature. The reaction was performed for 60 min under a vigorous shaking condition. Then, its fluorescence intensity was compared with the value at channel point G. According to our experimental data, it is believed that over 90% of the hybridization reaction is completed at channel position G. The changes in the relative fluorescence intensity along the channel length for the complementary and non-complementary target DNAs are plotted in Fig. 4. The fluorescence intensity changes with different molar ratios of the MB and target DNA were also investigated. The results are presented in Fig. 5(a). With an increase in the molar ratio from 0 to 1:1, the relative fluorescence intensity for the complementary target DNA gradually increased. However, there was no intensity change with the non-complementary target ...
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Citations
... This was confirmed by performing a series of flow rate ratios of continuous and dispersed phase (data not shown). Hybridization between two complementary ssDNAs took about 1–2 h both on substrate or in static solution, however, previous reports that such hybridization could be completed much faster in fluidic flow or microdroplets [41, 48, 49] at room temperature.Figure 12 shows smFRET of droplets generated through a T-type microfluidic as illustrated inFig. 11b. ...
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... In their study, a new hybridization analysis technique using a molecular beacon (MB) and a PDMS microfluidic channel was developed. In (Kim et al. 2007 ). ...
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