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Published on: October 13, 2017
Visual detection of G-quadruplex with mushroom derived highly fluorescent carbon quantum dots
Bhavini Kumari1, Rekha Kumari2, Prolay Das1
1Department of Chemistry, IIT Patna, Bihta, Patna, 801103, Bihar, India.
Abstract:
G-quadruplexes are secondary DNA structures frequently found in telomeres and DNA sequences related to gene regulation, etc. Herein, we report a label free, sensitive and visually detectable fluorescence based biosensing platform for the detection of G-quadruplexes in DNA. Highly fluorescent N-doped carbon quantum dot (CD) with enriched functional groups was synthesized from Ganoderma lucidum, an oriental fungus by using a green hydrothermal process. Noncovalent functionalization of CD was done with Hemin where Hemin/CD conjugate forms a quenched union. However, in presence of DNA sequences that contain G-quadruplexes, the fluorescence of CD is restored selectively. The fluorescence restoration of CD is attributed to the stripping of Hemin from Hemin/CD conjugate that preferably slide into the G quadruplexes leaving CD. This increase in CD fluorescence is easily detectable under hand-held UV light without any other instrumental intervention for G-quadruplex containing DNA only and not in any other DNA samples. Also, such selective fluorescent recovery was not observed with chemically synthesized CD that lack hydroxyl functionality.
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The Dot Product
Dot Product
In engineering, the dot product of any two vectors is the product of the magnitudes of the vectors and the cosine of the angle between them. It is denoted by a dot symbol between the two vectors.
Consider a vehicle pulling an object along the ground using a rope. If the rope makes an angle with the horizontal axis, the work done can be calculated using the dot product of the force applied and the object's displacement.
The dot...

