title: Fluorescence Quenching of CdSe/ZnS Quantum Dots by Using Black Hole Quencher Molecules Intermediated With Peptide for Biosensing Application.
abstract: Quantum dots (QDs) have recently been investigated as fluorescent probes for detecting a very small number of biomolecules and live cells; however, the establishment of molecular imaging technology with on-off control of QD fluorescence remains to be established. Here we have achieved the fluorescence off state of QDs with the conjugation of black hole quencher (BHQ) molecules intermediated with peptide by using streptavidin-QDs585 and biotin-pep-BHQ-1. The fluorescence of streptavidin-QDs585 was decreased by the addition of biotin-pep-BHQ-1 in a dose-dependent manner. It has been suggested that the decrease in QDs585 fluorescence occurred through a Förster resonance energy transfer (FRET) mechanism from the analysis of fluorescence intensity and lifetime of streptavidin-QDs585 and QDs585-pep-BHQ-1. QDs585 fluorescence could be quenched by more than 60% efficiency in this system. The sequence of intermediate peptide (pep) was GPLGVRGK, which can be cleaved by matrix metalloproteinases (MMPs) produced by cancer cells. QDs585-pep-BHQ-1 is thus expected to detect the MMP production by the recovery of QDs585 fluorescence as a new bioanalytical agent for molecular imaging.
authors: Graduate School of Engineering, Nagoya University , Furo-cho, Chikusa-Ku, Nagoya , Japan.
authors: Sreenadh Sasidharan
authors: SS
authors: Pillai
authors: † FIRST Research Center for Innovative Nanobiodevices, Nagoya University , Furo-cho, Chikusa-Ku, Nagoya , Japan.
authors: Hiroshi
authors: H
authors: Yukawa
authors: ‡ Institute of Innovation for Future Society, Nagoya University , Furo-cho, Chikusa-Ku, Nagoya , Japan.
authors: Daisuke
authors: D
authors: Onoshima
authors: § Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) , Hayashi-Cho, Takamatsu, Kagawa , Japan.
authors: Vasudevanpillai
authors: V
authors: Biju
authors: Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-Ku, Nagoya, Japan; †FIRST Research Center for Innovative Nanobiodevices, Nagoya University, Furo-cho, Chikusa-Ku, Nagoya, Japan; ‡Institute of Innovation for Future Society, Nagoya University, Furo-cho, Chikusa-Ku, Nagoya, Japan; §Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Hayashi-Cho, Takamatsu, Kagawa, Japan.
authors: Yoshinobu
authors: Y
authors: Baba
keywords: Black hole quencher (BHQ); Fluorescence resonance energy transfer; Matrix metalloproteinase; Quantum dots (QDs)