A hydrazono-quinoline-based chemosensor sensing In3+ and Zn2+: Via fluorescence turn-on and ClO- via color change in aqueous solution

Article abstract of DOI:10.1039/c9nj00899c

A new multi-target sensor, HQD ((E)-5-(diethylamino)-2-((2-(quinolin-2-yl)hydrazono)methyl)phenol), based on the hydrazono-quinoline moiety, was developed. Sensor HQD showed selectivity toward In³⁺ and Zn²⁺via fluorescence turn-on and ClO^-via color change from yellow to colorless. The respective limits of detection for In³⁺, Zn²⁺ and ClO^- were calculated to be 0.05, 0.08 and 3.10 μM, and were far below the WHO standard for zinc in drinking water (76.5 μM). Moreover, quantification of In³⁺ and Zn²⁺ was possible in real water samples. The processes of detection of In³⁺, Zn²⁺ and ClO^- by HQD were demonstrated with the analyses of ESI-MS data, Job's plots, UV-Vis and ¹H NMR titrations and computational studies.

Full text of DOI:10.1039/c9nj00899c

View Article Online
View Journal
NJC
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: C. Kim and A. Kim,
New J. Chem., 2019, DOI: 10.1039/C9NJ00899C.
Volume 40 Number
1
January 2016 Pages 1–846
This is an Accepted Manuscript, which has been through the
Royal Society of Chemistry peer review process and has been
accepted for publication.
NJC
New Journal of Chemistry
www.rsc.org/njc
A journal for new directions in chemistry
Accepted Manuscripts are published online shortly after
acceptance, before technical editing, formatting and proof reading.
Using this free service, authors can make their results available
to the community, in citable form, before we publish the edited
article. We will replace this Accepted Manuscript with the edited
and formatted Advance Article as soon as it is available.
You can find more information about Accepted Manuscripts in the
author guidelines.
Please note that technical editing may introduce minor changes
to the text and/or graphics, which may alter content. The journal’s
standard Terms & Conditions and the ethical guidelines, outlined
in our author and reviewer resource centre, still apply. In no
event shall the Royal Society of Chemistry be held responsible
for any errors or omissions in this Accepted Manuscript or any
consequences arising from the use of any information it contains.
ISSN 1144-0546
PAPER
Jason B. Benedict et al.
The role of atropisomers on the photo-reactivity and fatigue of
diarylethene-based metal–organic frameworks
rsc.li/njc

Page 1 of 25
New Journal of Chemistry
1
2
3
4
5
6
7
8
9
View Article Online
DOI: 10.1039/C9NJ00899C
3
+
2+
A hydrazono-quinoline-based chemosensor sensing In and Zn via fluorescence turn-
-
on and ClO via color change in aqueous solution
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
Ahran Kim, Cheal Kim*
Department of Fine Chemistry, Seoul National Univ. of Science & Technology (SNUT),
Seoul, 01811, South Korea. Fax: +82-2-972-9149; Tel: +82-2-972-6681; E-mail:
chealkim@seoultech.ac.kr
Abstract
A
new
multi-target
sensor
HQD
((E)-5-(diethylamino)-2-((2-(quinolin-2-
yl)hydrazono)methyl)phenol), based on hydrazono-quinoline moiety, has been developed.
3
+
2+
-
Sensor HQD showed selectivity toward In and Zn via fluorescence turn-on and ClO via
3
+
2+
color change from yellow to colorless. The respective limits of detection for In , Zn and
-
ClO were calculated to be 0.05, 0.08 and 3.10 μM, and far below than WHO standard for zinc
3+
2+
in drinking water (76.5 μM). Moreover, quantification of In and Zn was possible in real
3
+
2+
-
water sample. The detection processes of In , Zn and ClO by HQD were demonstrated
1
with the analyses of ESI-MS data, Job plots, UV-Vis and H NMR titrations and computational
studies.
3
+
2+
-
Keywords: In ; Zn ; ClO ; colorimetric chemosensor; fluorescent chemosensor;
computational studies
1

New Journal of Chemistry
Page 2 of 25
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
View Article Online
DOI: 10.1039/C9NJ00899C
1
. Introduction
In recent years, there have been numberless efforts toward developing efficient and simple
methods to recognize various metal ions and anions since they play widespread roles in
physiological, industrial, and chemical areas.1–4 Indium ion is a heavy metal ion and used in
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
5
great amounts in industrial and chemical fields. In spite of necessity of indium in these fields,
some reports pointed out that excess of indium is poisonous to human body and inhibits iron
6
metabolism. Zinc ion, the essential transition cation in the body, acts as a key role in cell
division, DNA binding, immune function and gene regulation.7,8 In contrast with these
2
+
important roles of zinc ion, abnormal level of Zn could be hazardous to our body, causing
Parkinson’s disease, ischemic stroke and immune deficiency.9,10 ClO (hypochlorite) is one of
the reactive oxygen species (ROS).11,12 It is a strong oxidant and essential part of immune
system against a variety of pathogens.13,14 Nonetheless, there are many evidence that excess
production of hypochlorite could cause health problems such as atherosclerosis, cancers, and
cardiovascular.15,16 Thus, it is necessary and essential to recognize and quantify the three
-
2+
3+
-
analytes (Zn , In , and ClO ) by simple, fast and efficient techniques.
2
+
3+
-
There are several methods to detect a certain level of Zn , In or ClO , like exchange resins,
charge separation, ion selective electrodes, and anodic stripping voltammetry.17–19 However,
some of them still have weakness like high cost, low sensitivity and complicated control.20–22
In contrast to these methods, chemosensors have some benefits such as easy control, low cost,
and simple instrumentation.23–25
Up to now, several functional groups have been employed to design effective chemosensors
2
+
3+
-
for detecting Zn , In , and ClO . They are quinoline, BODIPY, rhodamine dyes and Schiff
base.26–30 Our group have also developed several Schiff base chemosensors which could detect
2
+
3+
- 31-34
From the previous works, we found that all the three analytes (Zn2+,
Zn , In or ClO .
3+
-
In and ClO ) interacted with the chemosensors containing both the C=N bond and phenol
moiety. However, our indium sensors detected indium ion only in organic solvents,31,32 and
the sensors for zinc and hypochlorite showed the rather high limits of detection.33,34 To
overcome these features, we focused on designing a new chemosensor that could recognize
2
+
3+
-
Zn , In and ClO with relatively low limits of detection in aqueous solution. On the other
hand, hydrazinoquinoline is a well-known fluorophore and can act as a receptor to transition
2

Page 3 of 25
New Journal of Chemistry
1
2
3
4
5
6
7
8
9
View Article Online
DOI: 10.1039/C9NJ00899C
metal ions.35–37 In addition, 4-diethylaminosalicylaldehyde has been also used as a
fluorophore.38–40 Considering these properties of the two compounds, we synthesized a new
type of hydrazono-quinoline-based chemosensor via condensation reaction between 2-
hydrazinoquinoline and 4-diethylaminosalicylaldehyde, which might chelate to metal ions
and react with ROS via the oxidative cleavage, resulting in photo-physical change.
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
3
+
2+
Herein, we address a unique chemosensor HQD which could detect In and Zn through
-
fluorescent turn-on and ClO through color change from yellow to colorless. With fluorescent
1
and UV-Visible spectroscopy, Job plot analysis, ESI-MS spectrometry, H NMR titration and
computational studies, the sensing abilities and mechanisms of HQD to the three analytes
3
+
2+
-
In , Zn , and ClO were demonstrated.
2. Experimental
2
.1. General
Chemicals used were supplied from Sigma-Aldrich. Buffer solutions used in all the analyses
were set to 10 mM of bis-tris and their pH was 7.0 (except for the pH test and water sample).
1
13
A Varian spectrometer was adopted for H and C NMR measurements. For fluorescence
measurements, a Perkin Elmer LS45 was used. A Thermo Finnigan ion trap machine was
adopted for ESI-MS measurements. UV/Visible data were gained with a Perkin Elmer
spectrometer (Lambda 25 UV/Vis).
2
.2.
Synthesis
of
sensor
HQD
((E)-5-(diethylamino)-2-((2-(quinolin-2-
yl)hydrazono)methyl)phenol)
2
-Hydrazinoquinoline (2 mmol, 318 mg) was dissolved in methyl alcohol (5.0 mL) and 4-
diethylaminosalicylaldehyde (386 mg, 2 mmol) was added into the solution, which was stirred
1
for 5 h at 24°C. A yellowish solid was filtered and rinsed with cold EtOH (180 mg; 27 %). H
NMR (400 MHz, deuterated-DMSO) δ (ppm): 11.03 (s, 1H), 10.78 (s, 1H), 8.18 (s, 1H), 8.12
(
d, J = 8.8 Hz, 1H), 7.73 (d, J = 8.40 Hz, 1H), 7.56 (m, 2H), 7.25 (m, 3H), 6.25 (d, J = 8.8 Hz,
1
3
1
1
H), 6.14 (s, 1H), 3.34 (m, 4H), 1.11 (m, 6H), C NMR (100 MHz, deuterated-DMSO): δ
58.26, 154.68, 149.24, 142.40, 137.83, 129.70, 127.78, 125.81, 122.18, 109.57, 107.77,
3

New Journal of Chemistry
Page 4 of 25
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
View Article Online
DOI: 10.1039/C9NJ00899C
N O+H ([HQD+H ]), 335.19 (m/z);
+
+
1
03.69, 97.62, 43.79, 12.61 ppm. ESI-Mass for C20
H
22
4
found, 335.34.
3
+
2+
2
.3. Detection of In and Zn through fluorescence change
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
HQD (0.005 mmol) was dissolved in 5.0 mL DMF (dimethylformamide) to make a
concentrated solution (1 mM). 5 mL buffer was used to dissolve In(NO
3
)
3
and Zn(NO
3
) (0.05
2
mmol) to make their concentrated solutions (10 mM), respectively.
Fluorescence titrations
3
+
For In , 90.0 μL of the concentrated HQD was added to 2.910 mL of a mixture of
buffer/DMF (7:3) in a cuvette to produce 30 µM. 0.45-5 μL of the concentrated indium were
transferred to the HQD (30 μM), which was mixed for 15 sec. Their fluorescent data were
2
+
collected by using a fluorescence spectrometer. Similar steps were done also for Zn .
UV-Vis titrations
3+
For In , 60 μL of the concentrated HQD was added to 2.94 mL of a mixture of buffer/DMF
(7:3) in a cuvette to generate 20 µM of HQD. Then, 0.3-4.2 μL of the concentrated indium
were transferred to the HQD (30 μM), which was mixed for 15 sec. UV/Vis spectrometer was
employed to measure UV-Vis spectra. Similar steps were done also for Zn2+.
Job plot measurements
9
-81 µL of the concentrated HQD were diluted into 3 mL of a mixture of buffer/DMF (7:3)
in different cuvettes to produce 3-27 µM. UV/Vis spectrometer was employed to measure
UV-Vis spectra. Concentrated In3+ solution was transferred to the cuvettes to make total
concentration 30 µM. UV/Vis spectrometer was employed to measure their UV-Vis spectra.
2
+
Similar steps were done also for Zn .
pH tests
0.01 M of bis-tris buffer for pH 6-7 and tris-buffer for pH 8-9 was chosen, and their pH
was adjusted by using HCl and NaOH. 90 μL of HQD was added into buffer/DMF solution
7:3) in each cuvette. 4.5 μL of the concentrated In3+ was put into the solutions. Their
(
4

Page 5 of 25
New Journal of Chemistry
1
2
3
4
5
6
7
8
9
View Article Online
DOI: 10.1039/C9NJ00899C
fluorescent data were collected by using a fluorescence spectrometer. Similar steps were done
2
+
also for Zn .
Competitive experiments
Stock solutions (10 mM) of NaNO
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
3
, Ni(NO
, Fe(NO
were made in buffer.
3
)
2
, Cr(NO
3
)
3
, Ga(NO
3
)
3
, Ca(NO
3
3
)
2
2
,
,
Fe(ClO
4
)
2
, Al(NO
3
)
3
, Mn(NO
3
)
2
, Zn(NO
3
)
2
3
)
3
, Mg(NO
3
)
2
, Cd(NO
)
3 2
, Cu(NO
)
Co(NO
3
)
2
, Pb(NO
3
)
2
, In(NO
3
)
3
and KNO
3
3
+
For In , 4.5 μL of each cation was added into 2.91 mL of a mixture of buffer/DMF (7:3),
3
+
respectively. Then, 4.5 μL of In ion was added to the above solutions and mixed well. 90 μL
of HQD solution was diluted to the mixed solutions. Their fluorescent data were collected by
using a fluorescence spectrometer. Similar steps were done also for Zn2+.
1H NMR titration
HQD (40 μmol) dissolved in deuterated dimethylformamide (2.8 mL) was divided into 4
NMR tubes. Three different equiv (0.1, 0.25, and 0.5) of In(NO
3
) dissolved in deuterated
3
dimethylformamide were added into the solutions of HQD. After blending each solution for
1
15 sec, H NMR spectra were recorded.
Determination of indium and zinc in water sample
Monitoring indium ion level in real water samples was tested with HQD (30 μM). 1.89 mL
of drinking water, 0.21 mL of bis-tris buffer (0.1 M), and 900 L of DMF were mixed for the
test. Fluorescence spectra of all samples were recorded three times by using a fluorescent
2
+
spectrometer and their data was averaged. Similar steps were done also for Zn .
2.4. Quantum Yields
Quantum yields (Ф) were calculated by using fluorescein (Ф
F
= 0.92 in basic ethanol) as a
4
1
42
standard fluorophore. The equation of quantum yield is as follows :
Φ
F(X) = ΦF(S) (A
S
F
X
/ A
X
F ) (n
S X
/n
)2
S
Where the meaning of each abbreviation is
5

New Journal of Chemistry
Page 6 of 25
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
View Article Online
DOI: 10.1039/C9NJ00899C
Ф
F
: Quantum yield
A: Absorbance
F: The area of fluorescence emission curve
n: Refractive index of the solvent
s: Standard
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
x: Unknown
-
2
.5. Detection of ClO through color change
HQD (0.005 mmol) was dissolved in 5 mL DMF (dimethylformamide) to make a
concentrated solution (0.001 M). Distilled water was used for dissolving NaClO (0.5 mmol,
2 % dissolved in H O) to make 5 mL of a concentrated solution (100 mM).
1
2
UV-Vis titration
-
3
60 µL of HQD (1x10 M) was added into 2.94 mL of a mixture of buffer/DMF (9:1) in a
cuvette to produce 20 µM. 0.6-12.6 μL of the concentrated NaClO were put to the HQD in
cuvettes. UV/Vis spectrometer was employed to measure their UV-Vis spectra.
pH test
Britton-Robinson buffer was chosen for pH test and the pH was adjusted from pH 2 to 12
4
3
with 40 mM of CH
3
COOH, B(OH)
3
and phosphoric acid, and 200 mM of NaOH. 60 μL of
1
mM HQD was added into each different pH buffer/DMF solution (v/v, 9:1) in each cuvette.
-
1
2 μL of the concentrated ClO (100 mM) was put into the solutions. UV/Vis spectrometer
was employed to measure their UV-Vis spectra.
Competitive experiment
-
-
-
PO -
-
-
-
0
.1 mmol of (Et
4
N)X (X = Br , F , Cl , H
2
4
), (Bu
4
N)X (X = BzO , N
3
, OAc ), AcOOH,
t-BuOOH, NaNO
2
and H were dissolved in 1 mL of buffer to produce 100 mM. 0.06 mL
2
O
2
-3
of HQD (1x10 M) was added into a mixture of buffer/DMF solution (9:1) in cuvettes. 12 μL
of the concentrated anions was added into the solution in each cuvette. After mixing them, 12
-
μL of ClO was introduced into the solutions. UV-Vis spectra of the blended solutions in
cuvettes were analyzed by using a UV/Vis spectrometer.
6

Page 7 of 25
New Journal of Chemistry
1
2
3
4
5
6
7
8
9
View Article Online
DOI: 10.1039/C9NJ00899C
1H NMR titration
HQD (30 μmol) dissolved in deuterated dimethylformamide (2.1 mL) was divided into 3
NMR tubes. 1 and 2 equiv of NaClO (12 % dissolved in H O) were added into the solutions
2
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
of HQD. After blending each solution for 15 sec, H NMR spectra were recorded.
2
.6. Computational studies
DFT and TD-DFT calculations with Gaussian 09 program44 were performed for all
computational studies with the hybrid exchange-correlation functional B3LYP.45,46 The main
group elements were applied for the 6-31G (d, p) basis set,47,48 and In3+ and Zn2+ were
employed for the LANL2DZ ECP.49–51 CPCM52,53 was employed for the solvent effect of
3
+
water. To observe the transition energies of the optimized forms for HQD, In -2·HQD,
2
+
HQD-Zn and DCA (4-(diethylamino)-2-hydroxybenzoic acid), TD-DFT calculations with
the use of their ground state geometry (S
singlet transitions.
0
) was applied for the analysis of the lowest 20 singlet-
3
. Results and discussion
A new chemosensor HQD based on hydrazono-quinoline moiety was synthesized through
condensation reaction between 2-hydrazinoquinoline and 4-diethylaminosalicylaldehyde
1
13
(
Scheme 1). The compound HQD was identified by using the instruments like H and C
NMR, and ESI-MS spectrometers.
Scheme 1. Synthesis of HQD.
7

New Journal of Chemistry
Page 8 of 25
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
View Article Online
DOI: 10.1039/C9NJ00899C
3
+
2+
3
.1. Detection of In and Zn through fluorescence change
2
+
3+
2+
The sensing abilities of sensor HQD were studied towards metal ions, Mn , Al , Fe ,
2
+
3+
+
2+
2+
2+
2+
2+
3+
3+
2+
2+
+
3+
Co , Ga , Na , Cd , Mg , Zn , Ca , Cu , Fe , Cr , Pb , Ni , K , and In , in a mixture
of buffer/DMF (7:3) (Fig. 1). With excitation at 445 nm, HQD presented a very weak
fluorescence (Φ = 0.0036). When different metal ions (1.0 equiv) were added into HQD, only
indium and zinc exhibited notable fluorescent changes with fluorescence emissions at 525 and
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
5
28 nm (Φ = 0.0207 and 0.0310). Notably, HQD could detect indium ion in 70% aqueous
solution, whereas most of chemosensors for indium reported by a fluorescence turn-on
operated in organic solvents, except for two cases (Table S1).5,6,27,31,32,54–60
Fig. 1 Change of fluorescence spectra of HQD (0.03 mM) with 1 equiv of diverse cations.
3+
In order to study the binding between HQD and In , we performed fluorescent and UV-
Visible titrations. When indium ion was constantly added into HQD, there was the increase
of the emission spectrum at 525 nm up to 0.5 equiv of indium ion (Fig. 2). In UV-Visible
8

Page 9 of 25
New Journal of Chemistry
1
2
3
4
5
6
7
8
9
View Article Online
DOI: 10.1039/C9NJ00899C
titration, absorbance bands at 250 and 450 nm increased consistently and that at 380 nm
decreased (Fig. S1). Moreover, two obvious isosbestic points appeared at 294 and 425 nm
which meant that HQD and indium produced only a complex. The binding character between
3
+
HQD and In turned out to be a 2:1 with Job plot analysis (Fig. S2). The collected ESI-mass
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
+
3+
data supported the result of Job plot ([2·HQD(– 2·H ) + In ], calcd, 781.25; found, 781.37)
(Fig. S3).
3
+
Fig. 2 Change of fluorescence spectra of HQD (0.03 mM) with varied In concentrations.
The calibration curve of HQD with indium ion was set by the average value of fluorescence
titrations which were done three times. With the calibration curve, limit of detection (L.O.D.)
10
-2
and association constant were calculated to be 0.05 μM (Fig. 3) and 2 × 10 M (Fig. S4)
6
1
using 3σ/slope and Li’s equation , respectively. Importantly, the L.O.D. is the lowest value
among indium sensors previously reported (Table S1). Using the calibration curve (Fig. 3),
we determined indium level with HQD in real water sample. In drinking water, HQD could
quantify indium ion with decent recovery and R.S.D. values (Table 1). The pH dependence of
9

New Journal of Chemistry
Page 10 of 25
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
View Article Online
DOI: 10.1039/C9NJ00899C
3+
HQD and In -2·HQD was explored from pH 6 to 9 for examining practical application (Fig.
3
+
S5). In -2·HQD showed notable fluorescence enhancement at pH 6-7, while no fluorescence
was observed for HQD.
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
3
+
Fig. 3 L.O.D. for In by HQD (0.03 mM) based on the 3σ/slope.
3
+ a
Table 1. Determination of In .
Recovery
(%)
R.S.D. (n=3)
(%)
3
+
3+
Sample
In added (µM) In found (µM)
Drinking water
0.00
.60b
0.00
0.61
0
101.10
1.16
a
Conditions: [HQD] = 30.0 µM in buffer/DMF (7:3).
.6 μM of In ion was artificially added.
b
3+
0
1H NMR titration was performed to study binding behavior of HQD with indium (Fig. S6).
Addition of indium (0.5 equiv) into HQD solution induced the proton H12 on phenol to
1
0

Page 11 of 25
New Journal of Chemistry
1
2
3
4
5
6
7
8
9
View Article Online
DOI: 10.1039/C9NJ00899C
disappear. In addition, most of peaks on the imine and quinoline moieties moved to downfield.
More addition of indium (> 0.5 equiv) to HQD did not induce further movement of the peaks.
These outcomes suggested that the N atoms of the imine and quinoline moieties, and the O
atom of -OH might act as binding sites to indium ion. Integrating the results from Job plot,
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
3+
ESI-MS and H NMR titration, we suggested the suitable structure of In -2·HQD complex
(Scheme 2).
3
+
Scheme 2. Plausible structure of In -2∙HQD.
Competition experiment was executed for practical applicability of HQD as indium sensor
3+
2+
2+
2+
2+
3+
3+
2+
3+
2+
2+
2+
+
with various cations, Al , Ca , Zn , Cu , Cd , Fe , Ga , Fe , Cr , Pb , Ni , Co , K ,
+
2+
2+
Na , Mn and Mg (Fig. S7). Most cations did not inhibit the detection of indium ion by
2
+
2+
2+
3+
3+
2+
sensor HQD. However, Cd , Cu , Fe and Cr inhibited about 35-50%, and Fe and Co
did more than 90%.
Next, fluorescent and UV-Visible titrations were performed to examine the binding
2
+
characteristic of HQD with zinc. With increment of concentration of Zn , the fluorescent
emission at 528 nm gradually increased up to 1 equiv of Zn2+ (Fig. S8). In the UV-Visible
titration, the increase of absorbance at 250 and 440 nm and the decrease of absorbance at 400
nm were observed with two obvious isosbestic points at 291 and 416 nm (Fig. 4). These results
2
+
indicated that sensor HQD and zinc were converted to HQD-Zn complex as one species. In
2+
order to obtain more information on binding property between HQD and Zn , Job plot
1
1

New Journal of Chemistry
Page 12 of 25
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
View Article Online
DOI: 10.1039/C9NJ00899C
analysis was conducted, which showed a 1:1 complexation (Fig. S9). ESI-mass data was
collected to verify the result of Job plot (Fig. S10). The peak of 543.34 (m/z) was matched
+
2+
with [HQD(– H ) + Zn + 2·DMF] (m/z=543.21; calcd), indicating the 1:1 binding ratio
Scheme 3).
(
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
2
+
Fig. 4 Change of UV-Vis spectra of HQD (0.03 mM) with different Zn concentrations.
2
+
Scheme 3. Plausible structure of HQD-Zn .
2
+
Based on the fluorescence titration of HQD with Zn , the association constant (K) of 2.8
1
2

Page 13 of 25
New Journal of Chemistry
1
2
3
4
5
6
7
8
9
View Article Online
DOI: 10.1039/C9NJ00899C
4
-1
62
×
10 M was given using the equation of Benesi-Hildebrand (Fig. S11). The L.O.D. of
0
.08 μM was given using the calibration curve and this figure was far lower than WHO
6
3
guideline (76 μM) (Fig. S12). The sensing ability of HQD was also tested in real water
samples based on the calibration curve (Table 2). Drinking water was selected for the test, and
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
2+
the zinc ion level determined was very close to the concentration of Zn added artificially in
the sample.
2
+ a
Table 2. Determination of Zn .
2
+
2+
Zn added
µM)
Zn found
Recovery
(%)
R.S.D. (n=3)
(%)
Sample
(
(µM)
Drinking water
0.00
.60b
0.00
0
0.59
97.70
2.03
a
Conditions: [HQD] = 30.0 µM in buffer/DMF (7:3).
.6 μM of Zn ion was artificially added.
b
2+
0
In order to investigate practical ability of HQD, we tested its sensing ability in different pH
Fig. 5). HQD-Zn2+ exhibited a prominent fluorescence at pH 6-9, while HQD showed no
(
fluorescence. Therefore, HQD could detect zinc ion at biological pH range (6.0-8.4). To
3+
2+
examine efficiency of HQD, competition test was carried out with other metal ions, Al , Ca ,
2
+
2+
2+
3+
3+
2+
3+
2+
2+
2+
+
+
2+
2+
Zn , Cu , Cd , Fe , Ga , Fe , Cr , Pb , Ni , Co , K , Na , Mn and Mg (Fig. S13).
2
+
2+
2+
3+
Most cation did not interfere with the sensing of Zn by HQD, whereas Cu , Fe , Fe and
2+
2+
Co inhibited about 30-60% of the fluorescence of HQD-Zn .
1
3

New Journal of Chemistry
Page 14 of 25
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
View Article Online
DOI: 10.1039/C9NJ00899C
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
2
+
Fig. 5 Fluorescence intensity (528 nm) of HQD and HQD-Zn in different pH.
3
+
Lastly, it is a significant challenge to find the method capable of distinguishing In from
2
+
Zn , because they showed the fluorescence enhancement at nearly same position. As shown
in Figs. S5 and 5, fortunately, no fluorescence enhancement was observed for In3+ at pH 8,
while the strong fluorescence emission was done for Zn2+ at the same pH 8. When the
3
+
fluorescence of HQD turned on by the addition of a certain cation at pH 7, it would be In or
2
+
Zn . Then, we will recheck the fluorescent change at pH 8. If HQD would exhibit obvious
2+
fluorescence emission at pH 8, the metal ion could be Zn . With no the fluorescence
3
+
enhancement at pH 8, the metal ion could be In .
-
3
.2. Detection of ClO through color change
-
-
-
-
-, t-
The colorimetric detection towards various anions and ROS (ClO , Cl , OAc , F , NO
2
-
-, H
-
-
BuOOH, Br , H
2
PO
4
2
O
2
, BzO , N
3
and AcOOH) by sensor HQD was tested in
buffer/DMF solution (v/v, 9:1) (Fig. 6). Among the various anions and oxidizers tested, only
-
ClO could induce obvious spectral and color changes. Interestingly, this is the first case that
2
+
3+
-
a sensor can sense the three different analytes, Zn , In and ClO .
1
4

Page 15 of 25
New Journal of Chemistry
1
2
3
4
5
6
7
8
9
View Article Online
DOI: 10.1039/C9NJ00899C
(
a)
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
(b)
Fig. 6 (a) Change of UV-Vis spectra of HQD (0.02 mM) with 20 equiv of diverse anions and
ROS. (b) Color change of HQD (0.02 mM) with 20 equiv of different anions and ROS.
-
To comprehend sensing mechanism of HQD toward ClO , UV-Visible titration experiment
-
was achieved (Fig. 7). With gradual addition of ClO to HQD, the absorbance bands at 280
and 575 nm were increased and those at 260 and 400 nm were decreased. Based on the titration,
L.O.D. was found to be 3.10 μM (Fig. S14).
1
5

New Journal of Chemistry
Page 16 of 25
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
View Article Online
DOI: 10.1039/C9NJ00899C
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
Fig. 7 Change of UV-Vis spectra of HQD (0.02 mM) with varied hypochlorite concentrations.
In different pH, sensing ability was tested to study practical ability of HQD as a sensor
-
detecting ClO (Fig. S15). HQD exhibited an apparent yellow color at pH 3-12, whereas HQD
-
-
with ClO exhibited colorless at pH 3-9. Sensing ClO by HQD was possible between pH 3
and 9. Moreover, competition test with other anions and ROS was conducted (Fig. S16). There
was no interference from ROS species and most of anions, whereas H
2
O
2
and nitrite interfered
with 35-50%.
1
To get more insight on reaction mechanism between HQD and hypochlorite, H NMR
titration and ESI-MS analysis of HQD with NaClO (12 % dissolved in H O) were conducted
2
1
(Figs. S17 and S18). In H NMR titration, as the concentration of NaClO increased, C=N
proton H
8
was faded out, and H
7
and H12 disappeared due to the presence of H O in NaClO
2
-
solution. These observations led us to propose that ClO might cause the cleavage of the imine
C=N bond with oxidation. ESI-MS showed the production of DCA (m/z = 242.32 with a
1
6

Page 17 of 25
New Journal of Chemistry
1
2
3
4
5
6
7
8
9
View Article Online
DOI: 10.1039/C9NJ00899C
methanol as a solvent), an oxidative cleavage product of HQD (Fig. S18). Considering the
1
-
results of H NMR titration and ESI-MS, the suitable sensing mechanism of ClO by HQD
was shown in Scheme 4.
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
Scheme 4. Proposed sensing mechanism between HQD and ClO-.
3
.3. Computational studies
3+
2+
The structural information of In -2∙HQD and HQD-Zn and DCA, which was proposed
1
from Job plot, H NMR titration and ESI-MS data, was applied for optimizing their structures
3
+
2+
(
Fig. 8). The optimized structures showed that both In and Zn were bound to the N atoms
of the imine and quinoline moieties, and the O atom of the diethylaminophenol moiety with
3
+
octahedral and tetrahedral shapes, respectively. The electronic transitions of HQD, In -
2
+
2∙HQD, HQD-Zn , and DCA were investigated through TD-DFT calculations for minimized
geometries (S ). The molecular orbital (MO) contribution of HQD was assigned to be HOMO
LUMO transition at the first lowest excited state (407.41 nm), which was related to
intramolecular charge transfer (ICT) from the diethylaminophenol moiety to the quinolone
0
→
3
+
one (Fig. S19 and S21). In case of In -2∙HQD, the fourth lowest-excited state corresponded
to HOMO → LUMO+1 and HOMO-1 → LUMO transitions (430.18 nm), indicating ICT with
the decreased energy gap (Figs. S20 and S21). For HQD-Zn2+ complex, the first lowest-
excited state was matched with HOMO → LUMO transition (439.78 nm), which was also
characterized as ICT with the reduction of the energy gap between HOMO and LUMO (Fig.
3+
2+
S22 and S23). As shown in Fig. S21 and S23, the coordination of HQD to In and Zn led
to the decreases of the energy gap and the red shift of UV-Vis spectra. However, there was no
notable difference between MO transitions of HQD and its complexes. These results
1
7

New Journal of Chemistry
Page 18 of 25
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
View Article Online
DOI: 10.1039/C9NJ00899C
suggested that chelating with indium and zinc ion might form the rigid structures with HQD,
resulting in chelation-enhanced fluorescence (CHEF) effect.64–66 Considering all the results
1
from Job plots, ESI-mass analyses, H NMR titration and computational studies, we proposed
3
+
2+
the possible binding mechanisms and structures of In -2∙HQD and HQD-Zn (Schemes 2
and 3). For DCA, the MO contribution of the 1st lowest excited state corresponded with
HOMO → LUMO transition (288.21 nm) (Fig. S24). The electron density was shifted from
the diethylamino group to the carboxyl one, which was interpreted as ICT (Fig. S25). In
addition, the energy gap between HOMO and LUMO of DCA was larger than that of HQD,
and the difference was matched with the blue-shifted UV-Vis spectrum. Considering all the
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
results from Job plots, ESI-MS analyses, H NMR titration and theoretical calculations, we
-
proposed that HQD underwent the oxidative cleavage of the imine bond by ClO to generate
DCA (Scheme 4).
(a)
(b)
1
8

Page 19 of 25
New Journal of Chemistry
1
2
3
4
5
6
7
8
9
View Article Online
DOI: 10.1039/C9NJ00899C
(
c)
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
(d)
3+
2+
Fig. 8 Optimized structures of (a) HQD, (b) In -2∙ HQD, (c) HQD-Zn and (d) DCA.
4
. Conclusions
A novel versatile chemosensor (HQD) based on hydrazono-quinoline was developed for
3
+
2+
-
multiple analytes In , Zn and ClO , which was synthesized through condensation reaction
of 2-hydrazinoquinoline and 4-diethylaminosalicylaldehyde. The sensor showed fluorescence
3
+
2+
-
turn-on with In and Zn , and color change from yellow to colorless with ClO . Interestingly,
3
+
2+
this is the first case that the single sensor could detect these different three analytes (In , Zn
-
and ClO ). The limit of detection for indium, 0.05 μM, is the lowest value among the indium
sensors formerly addressed, to date. In addition, HQD could detect indium and zinc in real
3
+
2+
-
water sample. The detecting mechanisms of In , Zn and ClO with HQD were demonstrated
through computational studies. Therefore, sensor HQD would be a valuable example to
design sensors for targeting multiple analytes.
1
9

New Journal of Chemistry
Page 20 of 25
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
View Article Online
DOI: 10.1039/C9NJ00899C
Acknowledgements
We greatly acknowledge NRF (National Research Foundation of Korea)
2018R1A2B6001686) and KEITI (Korea Environment Industry & Technology Institute)
2016001970001).
(
(
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
2
0

Page 21 of 25
New Journal of Chemistry
1
2
3
4
5
6
7
8
9
View Article Online
DOI: 10.1039/C9NJ00899C
References
1
T.-B. Wei, J.-D. Ding, J.-F. Chen, B.-B. Han, X.-M. Jiang, H. Yao, Y.-M. Zhang and
Q. Lin, New J. Chem, 2018, 42, 1271.
2
3
A. Helal, S.-B. Kim and H.-S. Kim, Bull. Korean Chem. Soc., 2011, 32, 3123–3126.
L. Ma, T. Leng, K. Wang, C. Wang, Y. Shen and W. Zhu, Tetrahedron, 2017, 73,
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
306–1310.
4
5
6
Q. Lin, T.-T. Lu, X. Zhu, T.-B. Wei, H. Li and Y.-M. Zhang, Chem. Sci., 2016, 7,
5341–5346.
S. K. Kim, S. H. Kim, H. J. Kim, S. H. Lee, S. W. Lee, J. Ko, R. A. Bartsch and J. S.
Kim, Inorg. Chem., 2005, 44, 7866-7875.
D. Y. Han, J. M. Kim, J. Kim, H. S. Jung, Y. H. Lee, J. F. Zhang and J. S. Kim,
Tetrahedron Lett., 2010, 51, 1947–1951.
7
8
X. Wen, Q. Wang and Z. Fan, J. Lumin., 2018, 194, 366–373.
N. Narayanaswamy, D. Maity and T. Govindaraju, Supramol. Chem., 2011, 23, 703–
7
09.
9
1
W.-K. Dong, S. F. Akogun, Y. Zhang, Y.-X. Sun and X.-Y. Dong, Sens. Actuators B,
2
017, 238, 723–734.
0
J. Wan, W. Duan, K. Chen, Y. Tao, J. Dang, K. Zeng, Y. Ge, J. Wu and D. Liu, Sens.
Actuators B, 2018, 255, 49–56.
1
1
2
X. Cheng, S. Qu, Z. Zhong and W. Li, J. Fluoresc., 2017, 27, 1427–1433.
1
S. Goswami, S. Maity, A. C. Maity and A. K. Das, Sens. Actuators B, 2014, 204, 741–
7
45.
1
3
4
X. Lou, Y. Zhang, J. Qin and Z. Li, Sens. Actuators B, 2012, 161, 229–234.
1
G. Chen, F. Song, J. Wang, Z. Yang, S. Sun, J. Fan, X. Qiang, X. Wang, B. Dou and
X. Peng, Chem. Commun., 2012, 48, 2949-2951.
1
5
Y. Gao, Y. Pan, Y. Chi, Y. He, H. Chen and V. N. Nemykin, Spectrochim. Acta A,
2019, 206, 190–196.
16
17
F. Wei, Y. Lu, S. He, L. Zhao and X. Zeng, J. Fluoresc., 2012, 22, 1257–1262.
S. Mandal, Y. Sikdar, D. K. Maiti, R. Sanyal, D. Das, A. Mukherjee, S. K. Mandal, J.
K. Biswas, A. Bauz, A. Frontera and S. Goswami, J. Photochem. Photobiol. A, 2017,
3
34, 86–100.
1
8
9
B. Y. Kim, H. S. Kim and A. Helal, Sens. Actuators B, 2015, 206, 430–434.
V. K. Gupta, N. Mergu and A. K. Singh, Sens. Actuators B, 2015, 220, 420–432.
1
2
1

New Journal of Chemistry
Page 22 of 25
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
View Article Online
DOI: 10.1039/C9NJ00899C
2
0
M. S. Kim, S. Y. Lee, J. M. Jung and C. Kim, Photochem. Photobiol. Sci., 2017, 16,
677-1689.
1
2
1
2
A. J. Beneto and A. Siva, Sens. Actuators B, 2017, 247, 526–531.
2
Z. Luo, B. Liu, S. Si, Y. Lin, C. S. Luo, C. Pan, C. Zhao and L. Wang, Dye. Pigment.,
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
2
017, 143, 463–469.
23
24
25
26
N. Narayanaswamy and T. Govindaraju, Sens. Actuators B, 2012, 161, 304–310.
T. Sun, Q. Niu, Z. Guo and T. Li, Tetrahedron Lett., 2017, 58, 252–256.
L. Chen, T. Lou, C. Yu, Q. Kang and L. Chen, Analyst, 2011, 136, 4770-4773.
N. R. Chereddy, M. V. N. Raju, B. M. Reddy, V. R. Krishnaswamy, P. S. Korrapati, B.
J. M. Reddy and V. J. Rao, Sens. Actuators B, 2016, 237, 605–612.
27
28
29
30
31
32
A. Kim, J. H. Kang, H. J. Jang and C. Kim, J. Ind. Eng. Chem., 2018, 65, 290-299.
S. Yao and Y. Qian, Sens. Actuators B, 2017, 252, 877–885.
X. Xu and Y. Qian, Spectrochim. Acta A, 2017, 183, 356–361.
L. Yan, C. Hu and J. Li, Anal. Bioanal. Chem., 2018, 410, 7457–7464.
C. Kim and J. B. Chae, J. Fluoresc, 2018, 28, 1363–1370.
H. J. Jang, J. H. Kang, D. Yun and C. Kim, Photochem. Photobiol. Sci., 2018, 17,
1
247–1255.
3
3
H. J. Jang, A. Kim, J. M. Jung, M. Lee, M. H. Lim and C. Kim, Bull. Korean Chem.
Soc., 2018, 39, 1373-1379.
34
35
S. M. Hwang, A. Kim and C. Kim, Inorg. Chem. Commun., 2019, 101, 1–5.
L. M. R. Antinarelli, I. de Oliveira Souza, P. V. Zabala Capriles, J. Gameiro, E. A.
Britta, C. V. Nakamura, W. P. Lima, A. D. da Silva and E. S. Coimbra, Exp.
Parasitol., 2018, 195, 78–86.
3
3
3
6
7
8
C. C. Price, W. G. Jackson and A. Pohland, J. Am. Chem. Soc., 1948, 70, 2983–2988.
R. E. Jensen and R. T. Rflaum, Anal. Chem., 1966, 38, 1268–1269.
Y. J. Na, Y. W. Choi, J. Y. Yun, K. M. Park, P. S. Chang and C. Kim, Spectrochim.
Acta A, 2015, 136, 1649–1657.
3
9
0
Y. S. Kim, J. J. Lee, S. Y. Lee, T. G. Jo and C. Kim, RSC Adv., 2016, 6, 61505–61515.
4
D. T. Quang, J.-S. Wu, N. D. Luyen, T. Duong, N. D. Dan, N. C. Bao and P. T. Quy,
Spectrochim. Acta A, 2011, 78, 753–756.
4
1
D. Magde, R. Wong and P. G. Seybold, Photochem. Photobiol., 2002, 75, 327–334.
2
2

Page 23 of 25
New Journal of Chemistry
1
2
3
4
5
6
7
8
9
View Article Online
DOI: 10.1039/C9NJ00899C
4
2
L. Long, M. Huang, N. Wang, Y. Wu, K. Wang, A. Gong, Z. Zhang and J. L. Sessler,
J. Am. Chem. Soc., 2018, 140, 1870–1875.
4
3
4
H. T. S. Britton and R. A. Robinson, J. Chem. Soc., 1931, 0, 1456–1462.
4
M. J. Frisch, G. W. Trucks, H. B. Schlegel, G. E. Scuseria, M. A. Robb, J. R.
Cheeseman, J. A. J. Montgomery, T. Vreven, K. N. Kudin, J. C. Burant, J. M. Millam,
S. S. Iyengar, J. Tomasi, V. Barone, B. Mennucci, M. Cossi, G. Scalmani, N. Rega, G.
A. Petersson, H. Nakatsuji, M. Hada, M. Ehara, K. Toyota, R. Fukuda, J. Hasegawa,
M. Ishida, T. Nakajima, Y. Honda, O. Kitao, H. Nakai, M. Klene, X. Li, J. E. Knox, H.
P. Hratchian, J. B. Cross, C. Adamo, J. Jaramillo, R. Gomperts, R. E. Stratmann, O.
Yazyev, A. J. Austin, R. Cammi, C. Pomelli, J. W. Ochterski, P. Y. Ayala, K.
Morokuma, G. A. Voth, P. Salvador, J. J. Dannenberg, V. G. Zakrzewski, S. Dapprich,
A. D. Daniels, M. C. Strain, O. Farkas, D. K. Malick, A. D. Rabuck, K. Raghavachari,
J. B. Foresman, J. V. Ortiz, Q. Cui, A. G. Baboul, S. Clifford, J. Cioslowski, B. B.
Stefanov, G. Liu, A. Liashenko, P. Piskorz, I. Komaromi, R. L. Martin, D. J. Fox, T.
Keith, M. A. Al-Laham, C. Y. Peng, A. Nanayakkara, M. Challacombe, P. M. W. Gill,
B. Johnson, W. Chen, M. W. Wong, C. Gonzalez and J. A. Pople, GAUSSIAN 03
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
(revision B.02), Gaussian, Inc. Wallingford, CT.
45
46
47
48
49
50
51
52
53
54
55
A. D. Becke, J. Chem. Phys., 1993, 98, 5648–5652.
C. Lee, W. Yang and R. G. Parr, Phys. Rev. B, 1988, 37, 785–789.
P. C. Hariharan and J. A. Pople, Theor. Chim. Acta, 1973, 28, 213–222.
M. M. Francl, W. J. Pietro and W. J. Hehre, J. Chem. Phys., 1982, 77, 3654–3665.
W. R. Wadt and P. J. Hay, J. Chem. Phys., 1985, 82, 284–298.
P. J. Hay and W. R. Wadt, J. Chem. Phys., 1985, 82, 270–283.
P. J. Hay and W. R. Wadt, J. Chem. Phys., 1985, 82, 299–310.
V. Barone and M. Cossi, J. Phys. Chem. A, 1998, 102, 1995–2001.
M. Cossi and V. Barone, J. Chem. Phys., 2001, 115, 4708–4717.
Y.-C. Wu, H.-J. Li and H.-Z. Yang, Org. Biomol. Chem., 2010, 8, 3394–3397.
H. Kim, K. B. Kim, E. J. Song, I. H. Hwang, J. Y. Noh, P. G. Kim, K. D. Jeong and C.
Kim, Inorg. Chem. Commun., 2013, 36, 72–76.
5
5
6
7
Y.-M. Kho and E. Shin, Molecules, 2017, 22, 1569.
M. Lo Presti, S. El Sayed, R. Martínez-Máñez, A. M. Costero, S. Gil, M. Parra and F.
Sancenón, New J. Chem., 2016, 40, 9042–9045.
5
8
K. Ostrowska, A. Kaźmierska, M. Rąpała-Kozik and J. Kalinowska-Tłuścik, New J.
Chem., 2014, 38, 213–226.
2
3

New Journal of Chemistry
Page 24 of 25
1
2
3
4
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
View Article Online
DOI: 10.1039/C9NJ00899C
5
9
0
S. Y. Lee, M. Yang and C. Kim, Spectrochim. Acta A, 2018, 205, 622–629.
6
P. K. Mehta, G. W. Hwang, J. Park and K.-H. Lee, Anal. Chem., 2018, 90, 11256–
1264.
1
6
1
2
R. Yang, K. Li, K. Wang, F. Zhao, N. Li and F. Liu, Anal. Chem., 2003, 75, 612–621.
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
6
M. Mukhopadhyay, D. Banerjee, A. Koll, A. Mandal, A. Filarowski, D. Fitzmaurice,
R. Das and S. Mukherjee, J. Photochem. Photobiol. A, 2005, 175, 94–99.
6
6
3
4
World Health Organization, Guidelines for drinking-water quality - 4th edition, 2011.
S. K. Sheet, B. Sen, R. Thounaojam, K. Aguan and S. Khatua, J. Photochem.
Photobiol. A, 2017, 332, 101–111.
6
5
B. K. Kundu, P. Mandal, B. G. Mukhopadhyay, R. Tiwari, D. Nayak, R. Ganguly and
S. Mukhopadhyay, Sens. Actuators B, 2019, 282, 347–358.
66
W. Nasomphan, P. Tangboriboonrat and S. Smanmoo, J. Fluoresc., 2017, 27, 2201–
2212.
2
4

Page 25 of 25
New Journal of Chemistry
1
2
3
4
5
6
7
8
9
View Article Online
DOI: 10.1039/C9NJ00899C
Graphical Abstract
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
A multi-target sensor, based on hydrazono-quinoline, was developed for fluorescent turn-
3
+
2+
-
on detection of In and Zn and colorimetric detection of ClO .