Novel `turn off-on` sensors for detection of DNA-acrylamide interaction using ZnS quantum dots as a phosphorescent probe

Authors : Hayriye Eda Şatana KARA

Pages : 125-136

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Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :A novel `turn off-on` sensor for detection of interaction between DNA and acrylamide insert ignore into journalissuearticles values(ACR); was developed. In this method, L-cysteine capped Mn-doped ZnS quantum dots insert ignore into journalissuearticles values(QDs); were used as room temperature phosphorescent probes. In the ``turn-off`` mode, ACR was absorbed onto the surface of QDs via electrostatic interaction, which caused a quenching effect of room-temperature phosphorescence signal by photoinduced electron-transfer mechanism. ACR was removed from the QDs` surface with the addition of DNA. Thus, the phosphorescence emission of QDs was recovered and the system was turned to the ``turn-on`` mode. The quenching mechanism of QDs by ACR was collisional insert ignore into journalissuearticles values(dynamic); and the quenching constant, binding constant, and binding site number were calculated as 3.2 x 10$^{4\, }$ M$^{-1}$, 2.04 x 10$^{4\, }$ M$^{-1}$, and 1.2, respectively. An absorption spectrometric method was also used to evaluate ACR-DNA interaction and the binding constant insert ignore into journalissuearticles values(K); was found as 2.4 x 10$^{5\, }$ M$^{-1}$. The developed biosensor is simple, is free of interferences coming from autofluorescence and scattering light, and does not need any derivatization step or sample pretreatment.
Keywords : Acrylamide, DNA interaction, quantum dots, phosphorescence, photoinduced electron transfer