In this study, tetrabutyl 2,2′-bisbipyridine-5,5′-diylbis(methylene) diphosphonate (L) as fluorescence optical sensor was developed for selective determination of Zn2+.

Ashok Kumar S-K

Department of Chemistry

School of Advanced Sciences

Vellore Campus

Akella Sivaramakrishna

Priyankar Paira

R. Selva Kumara

Kari Vijayakrishnaa

C.V.S. Brahmmnanda Raob

N. Sivaramanb

Suban K. Sahooc

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

&nbsp;

&nbsp;

VIT University

New Journal of Chemistry

A new fluorescence receptor 2-(diethylamino)-N-(quinolin-8-yl) acetamide (L) was synthesized by simple reaction condition. The ligand HL is highly selective and sensitive towards Zn2+ ions over other tested metal ions. Upon interaction HL with Zn2+, the receptor HL showed a distinct fluorescence enhancement at 496 nm due to chelation enhanced fluorescence (CHEF) leading to visible fluorescence color change from blue to cyan. Subsequently, an in-situ generated L-Zn2+ when interacted with various anions, only with H2PO4− showed fluorescence quenching while other ions did not respond. Accordingly, the receptor HL was developed for the highly selective determination of Zn2+ and H2PO4− with the lowest detection limit (LOD) of 8 nM and 55 nM respectively. The binding mechanism of HL with Zn2+ and L-Zn2+ with H2PO4− were studied by both experimental and theoretical studies. The off-on-off sequential of HL with Zn2+ and H2PO4− were successfully employed for the INHIBIT logic gate response and cellulose assisted test strips proved, the practical application for qualitative analysis of Zn2+ and H2PO4− ions. Finally, the receptor HL was applied for the detection of Zn2+ in different water and pharmaceutical samples. © 2019 Elsevier B.V.

Inorganica Chimica Acta

An “Off-On-Off” type fluorescent chemosensor for the relay detection of Zn2+ and H2PO4− in aqueous environment

Inorganic Chemistry Communications

Highly selective fluorescent chemosensor for the relay detection of Al3+ and picric acid

Highly selective turn-on fluorogenic chemosensor for Zn2+ based on chelation enhanced fluorescence

In this communication, a new multifunctional Schiff-base (S) obtained by reacting hydrazine with 3,5-dichloro-salicylaldehyde. The sensing ability of S was studied with various metal ions by visual test, UV–Vis and spectrofluorometric techniques in THF:H2O (1:1, v/v) media. Accordingly, visual test was confirmed by changing initial colourless solution of S to yellow upon interaction with Mn2+ while for other ions, it did not respond in natural light. However, same solution composition when it was observed under UV light, it exhibits green fluorescent colour with Zn2+. In order to see more photo physical properties of S-Mn2+ and S-Zn2+ are studied through by spectrophotometric and spectrofluorometric methods respectively. Spectrophotometrically, neat S exhibits a strong absorption band at 365 nm upon interaction with Mn2+, it exhibits a new absorption band at 425 nm. Spectroflurometrically, a new emission peak was observed at 500 nm upon excitation of S-Zn2+ at 390 nm while other metal ions did not exhibit any emission properties. Further, the formation 3:2 binding stoichiometry between S with Mn2+ and Zn2+ were studied by using Job's plot and association constant for were estimated by Benesi-Hilderbrand (BH) method. The detection limit of S for Mn2+ and Zn2+ were found to be 3.6 × 10−7 M and 9.2 × 10−8 M respectively, which is much lower than the WHO guidance of their metal ions in drinking water. The coordination behaviour of S with Mn2+ and Zn2+ are well supported by NMR and theoretical calculations. © 2019 Elsevier B.V.

A multifunctional Schiff-base as chromogenic chemosensor for Mn2+ and fluorescent chemosensor for Zn2+ in semi-aqueous environment

A simple phosphoryl quinolone (L) based sensor has been synthesized for the selective recognition of Lu 3+ by spectrofluorimetric method. In methanol-water (1:1, v/v), the ligand L exhibits a weak emission peak at 400 nm upon excitation at 280 nm. Upon interaction with various f-metal and other selected metals from s, p, and d-block elements, the fluorescence of L is selectively enhanced in the presence of Lu 3+ due to the chelation enhanced fluorescence (CHEF) effects. The quantum yield (φ) of L (φ = 0.063) is enhanced to φ = 0.118 upon chelation with Lu 3+ ion. From the titration experiment, the limit of detection (LOD) of sensor L to recognize Lu 3+ is estimated down to 24.2 nM, which is much lower than the WHO guidelines (76 μM) in drinking water. The formation of host-guest complexation between L and Lu 3+ in 2:1 binding stoichiometry is studied by Job's method and the binding constant is estimated by band fit analysis (logK f = 5.1). Further, the coordination behaviour between L and Lu 3+ is well supported by FT-IR, 1 H NMR, 13 C NMR, 31 P NMR, ESI mass spectral data and the theoretical results. © 2019

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy

Highly selective CHEF-type chemosensor for lutetium (III) recognition in semi-aqueous media

A rapid and sensitive spectrophotometric method has been developed for the determination of Th4+ ions using tetra butyl 2,2′-bipyridine-5,5′-diylbis(methylene) diphosphonate (L) as a chemosensor. The selective complexation of L was examined with various f-metal ions like Th4+, U6+ and Ln's(III) ions and other selected metal ions (from s, p, and d-block elements). The chemosensor L selectively portrayed a naked-eye detectable colour change from colourless to pink with an appearance of a new charge transfer band at 320 nm and 525 nm. No noticeable spectral and colour changes of L were observed with other tested metal ions. This confirms high selectivity of L towards Th4+ ions. The Job's plot delineated the formation of a host–guest complex between L and Th4+ in 1:1 binding stoichiometry. The binding constant for the complexation of L-Th4+ was calculated from Benesi–Hildebrand (BH) plot and was found to be 6 × 103 M−1. The complexing ability L with Th4+ was supported by 31P NMR, FT-IR, UV-DRS, vibrating sample magnetometery and mass spectral data. The limit of detection (LOD) and limit of quantification (LOQ) of L for the analysis of Th4+ was calculated to be 2.02 μM and 6.1 μM, respectively. Finally, the chemosensor L was successfully applied for the quantification of Th4+ contents present in monazite sand, gas mantels and different water samples. © 2017 Elsevier B.V.

Sensors and Actuators B: Chemical

Development of highly selective chemosensor for thorium estimation

Inorganic Chemistry

A Highly Sensitive ESIPT-Based Ratiometric Fluorescence Sensor for Selective Detection of Al3+

Design of a highly sensitive and selective bulk optode based on fluorescence enhancement of N,N′-bis-(1-hydroxyphenylimine)2,2′-pyridil Schiff base: Monitoring of zinc(II) ion in real samples and DFT calculation

Journal of Materials Chemistry B

A novel fluorescent chemosensor based on tetra-peptides for detecting zinc ions in aqueous solutions and live cells

Journal of Fluorescence

A Novel Fluorescent Optode for Recognition of Zn2+ ion Based on N,N’-bis-(1-Hydroxypheylimine)2,5-Thiophenedicarobxaldehyde (HPTD) Schiff Base

Bipyridine bisphosphonate-based fluorescent optical sensor and optode for selective detection of Zn2+ ions and its applications

Journal	Data powered by TypesetNew Journal of Chemistry
Publisher	Data powered by TypesetRoyal Society of Chemistry (RSC)
ISSN	1144-0546
Open Access	0