The synthesis, electrochemical, optical, and metal-cation-sensing properties of ferrocene-glycine conjugates C 30H 38O 8N 8Fe (2) and C 20H 24O 4N 4Fe (3) have been documented. Both compounds 2 and 3 behave as very selective redox (ΔE 1/2 = 217 mV for 2 and ΔE 1/2 = 160 mV for 3), chromogenic, and fluorescent chemosensors for Hg 2+ cations in an aqueous environment. The considerable changes in their absorption spectra are accompanied by the appearance of a new low-energy peak at 630 nm (2, ε = 1600 M -1 cm -1; 3, ε = 822 M -1 cm -1). This is also accompanied by a strong color change from yellow to purple, which allows a prospective for the "naked eye" detection of Hg 2+ cations. These chemosensors present immense brightness and fluorescence enhancement (chelation-enhanced fluorescence = 91 for 2 and 42 for 3) following Hg 2+ coordination within the limit of detection for Hg 2+ at 7.5 parts per billion. © 2011 American Chemical Society.

Sundargopal Ghosh

Department Of Chemistry

Copper

Ferrocene

ferrous ion

Glycine

mercury

Water

article

chemical analysis

chemistry

Color

Electrochemistry

enzyme specificity

instrumentation

limit of detection

oxidation reduction reaction

solution and solubility

spectrofluorometry

ultraviolet spectrophotometry

Chemistry Techniques, Analytical

Ferrous Compounds

Oxidation-Reduction

Solutions

Spectrometry, Fluorescence

Spectrophotometry, Ultraviolet

Substrate Specificity

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Inorganic Chemistry

Two novel ferrocene-quinoline derivatives 3 (C22H19O2N3Fe) and 4 (C34H28O4N6Fe) have been synthesized and structurally characterized. Compound 3 exhibits good proton conductivity through 1D helical water chains. In addition, both compounds 3 and 4 selectively detect Zn2+ ions in water with a detection limit of 2 ppb through multiple channels. © 2015 The Royal Society of Chemistry.

RSC Advances

Unprecedented ferrocene-quinoline conjugates: Facile proton conduction via 1D helical water chains and a selective chemosensor for Zn(ii) ions in water

A set of triazole-based chromogenic and fluorescent chemosensors with amino acid/carbohydrate-fluorophore conjugates have been designed and synthesized. The metal cation-sensing properties of glycine-anthracene, C24H 24O4N4 (3), glycine-pyrene C26H 24O4N4 (4), glucose-anthracene, C 32H33O10N3 (5) and glucose-pyrene, C34H33O10N3 (6) bio-conjugates have been studied systematically. The significant changes in their absorption spectra are accompanied by a strong color change from light yellow to brown for 3 and 4 and colorless to greenish blue for 5 and 6. Receptors 3 and 4 have potential in the "naked eye" detection of Cu2+ and 5 and 6 for Pb 2+/Hg2+ ion. The receptors 3 and 4 show fluorescence diminution following Cu2+ coordination within the limit of detection at 0.89 parts per billion (ppb) and this is unprecedented, whereas the receptors 5 and 6 present drastic fluorescence quenching upon addition of Hg2+ and Pb2+ within the limit of detection at 4 and 2 ppb respectively. Interestingly, their fluorescence and colorimetric responses are preserved in the presence of water that can be used for the selective colorimetric detection of these ions in aqueous environments. Along with the spectroscopic data, combined 1H NMR titration of the complexes and the DFT studies suggest the proposed coordination modes. © 2014 The Royal Society of Chemistry.

Fulltext

Synthesis of triazole linked fluorescent amino acid and carbohydrate bio-conjugates: A highly sensitive and skeleton selective multi-responsive chemosensor for Cu(ii) and Pb(ii)/Hg(ii) ions

The electrochemical, optical, and metal cation sensing properties of the triazole-tethered ferrocene-anthracene conjugates, C48H 40FeO2N6 (3) and C52H 40FeO2N6 (4), and the ferrocene-pyrene conjugates, C29H25FeON3 (5) and C 31H25FeON3 (6), have been documented. All the compounds 3-6 behave as very selective redox, chromogenic, and "turn-on" fluorescent probes for Pb2+ ion in an aqueous environment (CH3CN/H2O, 2/8). The significant changes in their absorption spectra are accompanied by a strong color change from yellow to greenish blue, which allows a prospective use for the "naked eye" detection of Pb2+ ion over other competitor cations such as Hg 2+ and Cd2+. These chemosensors present immense brightness and fluorescence enhancement (chelation-enhanced fluorescence = 85 for 3 and 92 for 4) following Pb2+ coordination within the limit of detection at 2 ppb. Interestingly, their fluorescence, redox, and colorimetric responses are preserved in presence of water, which can be used for the selective colorimetric detection of Pb2+ ion in aqueous environment over Hg2+ and Cd2+ cations. All the compounds have been characterized by 1H, 13C NMR spectroscopy and electrospray ionization mass spectrometry (ESI-MS) spectrometric analysis, and the solid-state structures of 5 and 6 have been unequivocally established by X-ray diffraction analysis. © 2013 American Chemical Society.

Analytical Chemistry

Sensitive and selective redox, chromogenic, and "turn-on" fluorescent probe for Pb(II) in aqueous environment

The synthesis, electrochemical, optical and cation-sensing properties of two triazole tethered ferrocene derivatives, C25H25ON 3Fe2, 2 and C40H40O 2N6Fe3, 3 are presented. The solid state structure of compound 2 has been established by X-ray diffraction analysis which reveals that the unit cell of molecule 2 consists of 3-D helical chain formed via CH⋯N interaction and π⋯π stacking. The complexation properties of the receptors can be inferred either from redox shift or visual output response (colorimetric) for Hg2+ and Cu2+ cations. The common structural feature of these ligands is the presence of other ferrocene moiety as redox unit. Interestingly, the redox and colorimetric responses, towards Hg2+ are preserved in the presence of water (CH3CN/H2O, 2/8), which can be used for the selective colorimetric detection of Hg2+ in aqueous environment over other competitor cations. The changes in the absorption spectra are accompanied by the appearance of a new low energy (LE) peak at ca. 626 nm for 2 and 632 nm for 3 (2: Z = 669 M-1 cm-1 and 3: Z = 1150 M-1 cm-1), due to the change in color from yellow to purple for Hg 2+ cations in CH3CN/H2O (2:8).

Polyhedron

A triazole tethered triferrocene derivative as a selective chemosensor for mercury(II) in aqueous environment

Stripping Voltammetric Detection of Mercury(II) Based on a Bimetallic Au−Pt Inorganic−Organic Hybrid Nanocomposite Modified Glassy Carbon Electrode

Angewandte Chemie International Edition

Towards an Efficient Microsystem for the Real‐Time Detection and Quantification of Mercury in Water Based on a Specifically Designed Fluorogenic Binary Task‐Specific Ionic Liquid

Tetrahedron

Synthesis of nitrogen heterocycle-fused 1,2,4-benzothiadiazine-1,1-dioxide, quinazolinone, and pyrrolidinone derivatives with a guanidine joint via sequential aza-Wittig reaction/intramolecular NH-addition cyclization/nucleophilic substitution ring closure methodology, using functionalyzed carbodiimides as key intermediates

The Journal of Organic Chemistry

A Rhodamine-Based Hg2+Sensor with High Selectivity and Sensitivity in Aqueous Solution: A NS2-Containing Receptor

Organic & Biomolecular Chemistry

A highly selective and sensitive fluorescent turn-on sensor for Hg2+ and its application in live cell imaging

A highly selective redox, chromogenic, and fluorescent chemosensor for Hg 2+ in aqueous solution based on ferrocene-glycine bioconjugates

Journal	Inorganic Chemistry
ISSN	00201669
Open Access	No