Surface Immobilized Nucleic Acid–Transcription Factor Quantum Dots for Biosensing

Mingfu Chen (1) , Thuy Nguyen (1) , Nitinun Varongchayakul (1) , Chloé Grazon (1, 2, 3) , Margaret Chern (1) , R. C. Baer (1) , Sébastien Lecommandoux (2, 3) , Catherine Klapperich (1) , James E Galagan (1) , Allison M. Dennis (1) , Mark W. Grinstaff (1)

1 BU - Boston University [Boston]
2 LCPO - Laboratoire de Chimie des Polymères Organiques
3 Team 3 LCPO : Polymer Self-Assembly & Life Sciences

Immobilization of biosensors on surfaces is a key step toward development of devices for real‐world applications. Here the preparation, characterization, and evaluation of a surface‐bound transcription factor–nucleic acid complex for analyte detection as an alternative to conventional systems employing aptamers or antibodies are described. The sensor consists of a gold surface modified with thiolated Cy5 fluorophore‐labeled DNA and an allosteric transcription factor (TetR) linked to a quantum dot (QD). Upon addition of anhydrotetracycline (aTc)—the analyte—the TetR‐QDs release from the surface‐bound DNA, resulting in loss of the Förster resonance energy transfer signal. The sensor responds in a dose‐dependent manner over the relevant range of 0–200 µm aTc with a limit of detection of 80 nm . The fabrication of the sensor and the subsequent real‐time quantitative measurements establish a framework for the design of future surface‐bound, affinity‐based biosensors using allosteric transcription factors for molecular recognition.

Mots clés: biosensing; Förster resonance energy transfer; quantum dots; transcription factors

Domaines: Polymères; Matériaux; Matière Molle [cond-mat.soft]; Sciences du Vivant [q-bio]; Biotechnologies; Optique / photonique

Mingfu Chen, Thuy Nguyen, Nitinun Varongchayakul, Chloé Grazon, Margaret Chern, et al.. Surface Immobilized Nucleic Acid–Transcription Factor Quantum Dots for Biosensing. Advanced Healthcare Materials, 2020, 9 (17), pp.2000403. ⟨10.1002/adhm.202000403⟩. ⟨hal-02904157⟩