Supramolecular Reassembly of Self‐Exfoliated Ionic Covalent Organic Nanosheets for Label‐Free Detection of Double‐Stranded DNA

• Published in: Angewandte Chemie International Edition Vol. 57; no. 28; pp. 8443 - 8447
• Main Authors: Mal, Arindam, Mishra, Rakesh K., Praveen, Vakayil K., Khayum, M. Abdul, Banerjee, Rahul, Ajayaghosh, Ayyappanpillai
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 09.07.2018
• Edition: International ed. in English
• Subjects: Complementary DNA; Covalence; covalent organic framework; Deoxyribonucleic acid; DNA; Emission analysis; Ethidium bromide; Fluorescence; Icons; ionic assembly; ionic covalent organic nanosheets; label-free detection; Nanomaterials; Nanosheets; Nanotechnology; ionic assembly; label-free detection; ionic covalent organic nanosheets; DNA; covalent organic framework
• ISSN: 1433-7851; 1521-3773; 1521-3773
• DOI: 10.1002/anie.201801352

Ionic covalent organic nanosheets (iCONs), a member of the two‐dimensional (2D) nanomaterials family, offer a unique functional platform for a wide range of applications. Herein, we explore the potential of an ethidium bromide (EB)‐based covalent organic framework (EB‐TFP) that self‐exfoliates in water resulting in 2D ionic covalent organic nanosheets (EB‐TFP‐iCONs) for the selective detection of double‐stranded DNA (dsDNA). In an aqueous medium, the self‐exfoliated EB‐TFP‐iCONs reassemble in the presence of dsDNA resulting in hybrid EB‐TFP‐iCONs‐DNA crystalline nanosheets with enhanced fluorescence at 600 nm. Detailed steady‐state and time‐resolved emission studies revealed that the reassembly phenomenon was highly selective for dsDNA when compared to single‐stranded DNA (ssDNA), which allowed us to use the EB‐TFP‐iCONs as a 2D fluorescent platform for the label‐free detection of complementary DNA strands. Feelin' single, seein' double: Self‐exfoliated nanosheets of an ionic COF were used as a fluorescent platform for the selective detection of double‐stranded DNA (dsDNA). DNA induced the reassembly of the 2D nanosheets, and the associated fluorescence changes facilitated the discrimination of dsDNA from single‐stranded DNA (ssDNA) and other phosphates.