title: Nanoarchitectonics of Small Molecule and DNA for Ultrasensitive Detection of Mercury.
abstract: Reliable and ultrasensitive detection of mercury ions is of paramount importance for toxicology assessment, environmental protection, and human health. Herein, we present a novel optoelectronic approach based on nanoarchitectonics of small-molecule templated DNA system that consists of an adenine (A)-conjugated small organic semiconductor (BNA) and deoxyribo-oligothymidine (dTn). This mutually templated dynamic chiral coassembly system (BNAn-dTn) with tunable chiroptical, morphological, and electrical properties is tapped in to enable ultrasensitive and selective detection of inorganic and organometallic mercury in water. We observe a rapid transformation of the BNAn-dTncoassembly into a metallo-DNA duplex [dT-Hg-dT]nin the presence of mercury, which is utilized for a chiro-optical and conductivity-based rapid and subnanomolar sensitivity (≥0.1 nM, 0.02 ppb) to mercury ions in water (∼100 times lower than United States Environmental Protection Agency tolerance limit). This ultrasensitive detection of inorganic and organometallic mercury is driven by a novel chemical design principle that allows strong mercury thymine interaction. This study is anticipated to inspire the development of future templated DNA nanotechnology-based optoelectronic devices for the rapid and ultrasensitive detection of numerous other toxic analytes.
authors.affiliation: Bioorganic Chemistry Laboratory, New Chemistry Unit and ‡Molecular Electronics Lab, Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur P.O., Bengaluru 560064, Karnataka, India.
authors.forename: M
authors.initials: M
authors.lastname: Pandeeswar
authors.affiliation: Bioorganic Chemistry Laboratory, New Chemistry Unit and ‡Molecular Electronics Lab, Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur P.O., Bengaluru 560064, Karnataka, India.
authors.forename: Satyaprasad P
authors.initials: SP
authors.lastname: Senanayak
authors.affiliation: Bioorganic Chemistry Laboratory, New Chemistry Unit and ‡Molecular Electronics Lab, Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur P.O., Bengaluru 560064, Karnataka, India.
authors.forename: T
authors.initials: T
authors.lastname: Govindaraju
mesh_terms: D015374:Biosensing Techniques; D004247:DNA; D057230:Limit of Detection; D008628:Mercury / Q000737:chemistry*; D053768:Metal Nanoparticles; D049329:Nanostructures; D013941:Thymine; D014867:Water
chemical_list: D014867:Water; D004247:DNA; D008628:Mercury; D013941:Thymine
keywords: chiroptical and electrical detection; environmental pollutant; small organic semiconductor-DNA nanoarchitectonics; ultra sensitive detection of mercury