Journal
ACS APPLIED MATERIALS & INTERFACES
Volume 7, Issue 30, Pages 16458-16465Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acsami.5b03662
Keywords
G-quadruplex; thioflavin T; conjugated polymer; Foster resonance energy transfer; FRET; thrombin
Funding
- National Basic Research Program of China [2012CB933301, 2012CB723402]
- National Natural Science Foundation of China [21005040, 51173080, 21305070]
- Ministry of Education of China [IRT1148]
- Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) [YX03001]
- Natural Science Foundation of Jiangsu Province, China [BM2012010, BK20130861]
- Synergetic Innovation Center for Organic Electronics and Information Displays
- Jiangsu Government
- Program of Scientific Innovation Research of College Graduate in Jiangsu Province [KYLX_0792]
Ask authors/readers for more resources
We report a new Foster resonance energy transfer (FRET) system that uses a special dye, thioflavin T (ThT), as an energy acceptor and a water-soluble conjugated polymer (CP) with high fluorescence as an energy donor. A simple, label-free, and sensitive strategy for the detection of thrombin in buffer and in diluted serum was designed based on this new system using ThT as an efficient inducer of the G-quadruplex. The difference between the blank and the positive samples was amplified due to distinctive FRET signals because thrombin has little effect on the intercalation of ThT into the G-quadruplex. In the absence of the target, ThT induces the aptamer to form a G-quadruplex and intercalates into it with strong fluorescence. The electrostatic attractions between the negatively charged G-quadruplex and positively charged CP allow a short donor-acceptor distance, resulting in a high FRET signal. However, in the presence of the target, the aptamer forms a G-quadruplex-thrombin complex first, followed by the intercalation of ThT into the G-quadruplex. A long distance exists between the donor and acceptor due to the strong steric hindrance from the large-sized thrombin, which leads to a low FRET signal. Compared with previously reported strategies based on the FRET between the CP and dye, our strategy is label-free, and the sensitivity was improved by an order of magnitude. Our strategy also shows the advantages of being simple, rapid (about 50 min), sensitive, label-free, and low-cost in comparison to strategies based on the FRET between quantum dots and dyes.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available