TY - JOUR
T1 - Sensitive single-color fluorescence "off-on" switch system for dsDNA detection based on quantum dots-ruthenium assembling dyads
AU - Zhang, Rui
AU - Zhao, Dongxu
AU - Ding, Hui Guo
AU - Huang, Yan Xiang
AU - Zhong, Hai Zheng
AU - Xie, Hai Yan
PY - 2014/6/15
Y1 - 2014/6/15
N2 - Due to the high importance of detecting DNA with both fast speed and high sensitivity, we proposed a new dsDNA detection method relying on a novel single-color fluorescence "off-on" switch system. Water-soluble glutathione capped CdTe QDs (emission at 605nm) was prepared for taking advantage of the readily tunable emission property of QDs. Initially, QDs was completely quenched by the Ru(phen)2(dppz)2+, as the spontaneous formation of QDs-Ru assembling dyads. Then, in the case of the addition of dsDNA, the Ru(phen)2(dppz)2+ was removed away from the CdTe QDs, producing free CdTe QDs and the Ru-dsDNA complex. Both of them could be excited at the same wavelength and emit overlaid fluorescence. This single-color fluorescence "off-on" signal was sensitive to the concentration of dsDNA. Native dsDNA with the concentration of 10pg/mL could be detected when 0.5nM CdTe QDs was used, and ssDNA, RNA or BSA had no interference on it. With this system, the dsDNA samples of hepatitis B virus (HBV) patients were tested. The results were in good agreement with those detected by fluorescence quantitative PCR (P>0.05), and for those samples with very low DNA concentrations, this system could provide more accurate results, demonstrating the possible clinical applicability of this "off-on" switch system. For this system, chemical conjugation or labeling of probes is not required, and unmodified native DNA targets could be detected in less than half an hour. Therefore, a simple, fast, sensitive, low cost, highly selective and practically applicable detection system for dsDNA has been described.
AB - Due to the high importance of detecting DNA with both fast speed and high sensitivity, we proposed a new dsDNA detection method relying on a novel single-color fluorescence "off-on" switch system. Water-soluble glutathione capped CdTe QDs (emission at 605nm) was prepared for taking advantage of the readily tunable emission property of QDs. Initially, QDs was completely quenched by the Ru(phen)2(dppz)2+, as the spontaneous formation of QDs-Ru assembling dyads. Then, in the case of the addition of dsDNA, the Ru(phen)2(dppz)2+ was removed away from the CdTe QDs, producing free CdTe QDs and the Ru-dsDNA complex. Both of them could be excited at the same wavelength and emit overlaid fluorescence. This single-color fluorescence "off-on" signal was sensitive to the concentration of dsDNA. Native dsDNA with the concentration of 10pg/mL could be detected when 0.5nM CdTe QDs was used, and ssDNA, RNA or BSA had no interference on it. With this system, the dsDNA samples of hepatitis B virus (HBV) patients were tested. The results were in good agreement with those detected by fluorescence quantitative PCR (P>0.05), and for those samples with very low DNA concentrations, this system could provide more accurate results, demonstrating the possible clinical applicability of this "off-on" switch system. For this system, chemical conjugation or labeling of probes is not required, and unmodified native DNA targets could be detected in less than half an hour. Therefore, a simple, fast, sensitive, low cost, highly selective and practically applicable detection system for dsDNA has been described.
KW - DsDNA detection
KW - Fluorescence
KW - Off-on switch
KW - Quantum dots
KW - Single-color
UR - http://www.scopus.com/inward/record.url?scp=84892845428&partnerID=8YFLogxK
U2 - 10.1016/j.bios.2013.12.059
DO - 10.1016/j.bios.2013.12.059
M3 - Article
C2 - 24463196
AN - SCOPUS:84892845428
SN - 0956-5663
VL - 56
SP - 51
EP - 57
JO - Biosensors and Bioelectronics
JF - Biosensors and Bioelectronics
ER -
