Metal detection by Rhodamine dyes supported on silica surface

허기석,김치관,도정윤 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.1

Rhodamine fluorophore has attracted considerable interest from chemists on account of its strong emission. A lot of Rhodamine-derivatives have been developed for the detection of metal ions(Cu²⁺, Hg²⁺, Al³⁺, Ca²⁺). For the selective recognition of a heavy metal ions, sulfur-based and oxygen-based functional groups were considered during Rhodamine derivation. Metal coordination opens the ring of Rhodamine derivative to change absorptive and emissive properties. The ring opening and ring closure reactions are reversible depending on metal species and their concentration. We measured complex constants of Rhodamine and metal ions and compared according to the number of heteroatom (O, S) bound to Rhodamine. Rhodamine hydrazones with several sulfur groups exhibited a selective response to Hg²⁺. Fluorescent silica nanoparticles were prepared through covalent binding of the Rhodamine to NH₂-rich silica. The metal binding of silica particles viewing fluorescence is discussed.

양이온 아크릴고분자에 결합된 로다민 화학센서 개발과 구리(Ⅱ)이온의 선택적 검출

안성진(Sungjin Ahn),신상빈(Sang Bin Shin),조혁이(Hyeok-yi Jo),도정윤(Jung Yun Do) 한국고분자학회 2018 폴리머 Vol.42 No.5

금속의 선택적 검출을 위한 수용성 로다민 발색제와 수용성 고분자결합에 결합된 발색제를 개발하였다. 술폰염을 포함하는 알킬케톤과 로다민의 하이드라자이드의 이민형성 반응으로 수용성 발색물질이 합성되었다. 알킬사슬에 황원자가 도입된 로다민 발색제는 구리(Ⅱ)이온에 강한 선택성을 보였다. 알킬케톤으로 유도된 아크릴 단분자와 양이온 아크릴 단분자 methacrylatoethyl trimethylammonium chloride(AETMA)로부터 공중합 고분자를 합성하였고, 이에 로다민을 도입하여 로다민 결합 수용성 고분자를 제조하였다. 고분자의 점도측정을 통한 평균분자량은 6.5×10<SUP>4</SUP> g/mol이었으며 약 5 mol%의 로다민을 함유하였다. 고분자에 결합된 아마이드 작용기는 금속과 결합하는 성질 때문에 금속 발색제 로다민의 검출능력을 저하시킨다. 로다민결합 고분자의 구리(Ⅱ)이온에 대한 높은 선택성을 흡수분광분석을 통해 관찰하였다. 구리(Ⅱ)이온 검출에서 흡광도는 10일 이상 동안 지속적으로 상승하는 특성을 보였다. 로다민 유도체의 수은에 대한 약한 감응특성은 고분자 결합을 통해서 부분적으로 향상되었다. Water-soluble rhodamine and polymeric chemosensors were developed for copper detection. A new rhodamine derivative was synthesized through imine formation of rhodamine-hydrazide and a ketone carrying sulfonium salt, and a sulfide linkage for selective Cu2+ sensing in water. A copolymer of a ketone-acrylate with methacrylatoethyl trimethylammonium chloride was synthesized, which was treated with rhodamine-hydrazide to generate a polymeric sensor. The viscosity average molecular weight of the polymer was 6.5×10<SUP>4</SUP> g/mol. The polymer has a rhodamine content of ca. 5 mol% through 1H NMR analysis. Amide bonds caused to decrease the metal sensitivity of the rhodamine sensor because they are capable of absorbing metal ions. The Cu<SUP>2+</SUP> sensing of the polymeric rhodamine sensor was examined with light absorption intensity at 560 nm. The slow Cu<SUP>2+</SUP> binding of the polymeric sensor was observed over 10 days. Additionally, Hg<SUP>2+</SUP> sensing activity of the polymer sensor was enhanced compared to the rhodamine sensor.

Selective metal detection by modified Rhodamine dyes supported on silica surface

허기석,정민영,도정윤 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.0

Rhodamine fluorophore has attracted considerable interest from chemists on account of its strong emission. A lot of Rhodamine-derivatives have been developed for the detection of metal ions. For the selective recognition of a heavy metal ions, a sulfur-based functional group and oxygen-based functional group were considered during Rhodamine derivation. Metal coordination opens the ring of Rhodamine-derivative to change absorptive property. The ring opening and ring closure reactions are reversible and controllable with several coordination conditions. We examine the coordination effect according to the number of heteroatom (O, S) bound to Rhodamine. Heterocycles such as 1,3-dioxolane and 1,3-dithiolane are expected to form the better metal coordination kinetically, compared to the corresponding acyclic system. Fluorescent silica nanoparticles were prepared using NH2-rich silica surface.

A highly selective fluorescent chemosensor for Hg²⁺ based on a squaraine–bis(rhodamine-B) derivative: Part II

Lee, Sehoon,Rao, Boddu Ananda,Son, Young-A Elsevier 2015 Sensors and actuators. B Chemical Vol.210 No.-

<P><B>Abstract</B></P> <P>Herein, we report an effective strategy based on coordination-induced signaling by introducing a rhodamine B group linkage into squaraine–diamine dyads as a reversible switch. The optimized design, synthesis and application of a new optical squaraine–bis(rhodamine-B) chemosensor (<B>SRB</B>) as an ‘off–on’ fluorescent probe for the detection of Hg<SUP>2+</SUP> ions were investigated. <B>SRB</B> exhibited high selectivity toward Hg<SUP>2+</SUP> in the presence of various metal ions, such as Al<SUP>3+</SUP>, Ag<SUP>+</SUP>, Co<SUP>2+</SUP>, Cs<SUP>+</SUP>, Cu<SUP>2+</SUP>, Fe<SUP>3+</SUP>, K<SUP>+</SUP>, Li<SUP>+</SUP>, Mg<SUP>2+</SUP>, Na<SUP>+</SUP>, Ni<SUP>2+</SUP>, Pb<SUP>2+</SUP>, and Zn<SUP>2+</SUP>, and the resulting complex [<B>SRB</B>–Hg<SUP>2+</SUP>] was investigated using UV–vis and fluorescence spectroscopy in acetonitrile (CH<SUB>3</SUB>CN). The ‘off–on’ fluorescence and color signal change of the probe are based on a Hg<SUP>2+</SUP>-triggered domino reaction that employs the open-ring form of rhodamine spirolactam to regain the conjugated system of the rhodamine skeleton. The mechanism for the opening of the rhodamine spirolactam ring induced by Hg<SUP>2+</SUP> binding and the 1:1 stoichiometric structure of <B>SRB</B> and Hg<SUP>2+</SUP> were confirmed using a Job's plot estimation, optical titration and FT-IR. Subsequently, a <B>SRB</B>–Hg<SUP>2+</SUP> complex chemosensor was employed to detect CN<SUP>−</SUP> in the presence of different anions, such as Br<SUP>−</SUP>, CH<SUB>3</SUB>COO<SUP>−</SUP> or AcO<SUP>−</SUP>, Cl<SUP>−</SUP>, ClO<SUB>4</SUB> <SUP>−</SUP>, F<SUP>−</SUP>, HPO<SUB>4</SUB> <SUP>−</SUP>, HSO<SUB>4</SUB> <SUP>−</SUP>, I<SUP>−</SUP>, N<SUB>3</SUB> <SUP>−</SUP>, NO<SUB>3</SUB> <SUP>−</SUP>, PF<SUB>6</SUB> <SUP>−</SUP> and SCN<SUP>−</SUP>, in acetonitrile. In addition, this sensor exhibited highly selective and sensitive recognition of cyanide ions upon the addition of Hg<SUP>2+</SUP> with a color change back to colorless in the same solution. Finally, <B>SRB</B> was successfully applied with the PEGDMA polymer to sense Hg<SUP>2+</SUP> ions, which was analyzed using fluorescence confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) images.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Design and synthesis of a new squaraine–bis(rhodamine-B) (<B>SRB</B>) chemosensor was in high yield. </LI> <LI> Chemosensor <B>SRB</B> as an ‘off–on’ fluorescent probe for the detection of Hg<SUP>2+</SUP> ion. </LI> <LI> The <B>SRB</B>–Hg<SUP>2+</SUP> complex structure was confirmed via FT-IR studies. </LI> <LI> The reversibility of the <B>SRB</B>–Hg<SUP>2+</SUP> complex was realizable by the introduction of CN<SUP>−</SUP> ion. </LI> <LI> <B>SRB</B> was mixed with PEGDMA polymer for chemosensing the Hg<SUP>2+</SUP> ion. </LI> </UL> </P>

Carbon nanodots functionalized with rhodamine and poly(ethylene glycol) for ratiometric sensing of Al ions in aqueous solution

Kim, Yujun,Jang, Geunseok,Lee, Taek Seung Elsevier Sequoia 2017 Sensors and actuators. B Chemical Vol.249 No.-

<P><B>Abstract</B></P> <P>Carbon nanodots (CDs) functionalized with a rhodamine moiety and poly(ethylene glycol) (PEG) were used for selective fluorometric detection of Al ions. When the Al ion was exposed to the modified CDs, the lactam ring of the rhodamine moiety opened and, subsequently, was ready to absorb the emission of CDs, leading to a Förster resonance energy transfer (FRET)-based sensing protocol in aqueous media. A selective response to Al ion was observed in an aqueous solution, which was attributed to the ability of the rhodamine moiety to interact with the Al ion, but not with other metal ions. PEG played a role in improving the water-solubility of rhodamine-appended CDs that were intrinsically hydrophobic. The FRET-based mechanism provideed a ratiometric sensing that could remove possible interference via self-calibration of two emission bands.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Fluorescent carbon nanodots (CDs) are synthesized with rhodamine moiety and PEG. </LI> <LI> The CDs shows excellent solubility in aqueous solution because of the presence of PEG. </LI> <LI> The CDs showed excellent ratiometric sensing toward Al ions via FRET. </LI> <LI> The CDs shows high selectivity toward Al ion, even in the mixed metal ion solution. </LI> </UL> </P>

A Novel Rhodamine 6G Based Colorimetric turn-on Chemosensor for Al³⁺

이선혜,전근,신승림,안경룡,이승은 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.1

A new colorimetric chemosensor for Al³⁺ based on Rhodamine 6G was simply synthesized and investigated for photophysical properties. Rhodamine 6G derivated colorimetric chemosensor(P4) was designed and synthersized by imine synthesis of rhodamine6G ethylenediamine and 8-chloroquinoline-2-carboaldehyde. Chemosensor(P4) displayed obvious color change from colorless to pink (under normal light) and non-fluorescent to yellowish-green fluorescent in the Al³⁺ direction in the acetonitrile and methylene chloride (v/v = 9:1) solution. And various metal ions including Ag⁺, K⁺, Li⁺, Na⁺, Ca²⁺, Cd²⁺, Co²⁺, Ni²⁺, Zn²⁺, Ba²⁺, Mg²⁺, Fe²⁺, Cs⁺, Fe³⁺, Hg²⁺, Cu²⁺, Tb³⁺, Eu³⁺, Gd³⁺ caused less or smaller UV-spectral changes. The 2:3 stoichiometry of sensor complex P4+ Al³⁺ was confirmed by Job’s plot(UV-vis) and UV absorbance titration.

새로운 로다민 6G 플로렌 유도체의 합성과 형광 특성

김기백 ( Ki Back Kim ),김재현 ( Jae Hyun Kim ),장승현 ( Seung Hyun Chang ) 한국화상학회 2014 한국화상학회지 Vol.20 No.1

로다민 화합물은 형광 이 강하고 광학적 특성이 광범위해서 금속이온 분석에 널리 사용되고 있다. 최근 들어 여러 가지 여러 종류의 다양한 금속 이온을 감지하는 메카니즘은 spirocycle과 open-cycle형 구조변화를 통해 생긴다. 이 논문에서는 새로운 fluorene이 함유된 rhodamin 6G 유도체를 합성하였다. 합성한 화합물이 금속 이온 Fe2+와 Al3+ 에 선택성이 좋은 것을 확인하였다. Rhodamine is a dye used extensively as a fluorescent labeling reagent due to its excellent photophysical properties. Recently, various rhodamine-based turn-on fluorescent probes for metal ion has been proposed. The cation sensing mechanism of these probes is based on the change in structure between the spirocyclic and open-cycle forms. Here in, we report that a new rhodamine 6G derivative containing fluorene moiety behaves as a dual channel fluorescent probe for Fe2+ and Al3+.

Rhodamine spirolactam sensors operated by sulfur-cooperated metal complexation

Heo, Gisuk,Lee, Dahye,Kim, Chi Gwan,Do, Jung Yun Elsevier 2018 Spectrochimica acta. Part A, Molecular and biomole Vol.188 No.-

<P><B>Abstract</B></P> <P>New rhodamine Schiff base sensors were developed to improve selective sensing by introducing sulfide, ester, and dithiocarbonate groups, as well as using ketones coupled to rhodamine-hydrazine. Metal sensing proceeded through the 1:1 complexation of the metal ion for most sensors in the presence of Cu<SUP>2+</SUP> and Hg<SUP>2+</SUP>. A sensor carrying a dithiocarbonate group responded selectively to Hg<SUP>2+</SUP> showing a strong colorimetric change and intense fluorescence. The association constants of the sensors were determined from a linear plot performed at micro-molar concentrations to afford values in the range of 10<SUP>4</SUP>. Sensing was interrupted at the initial time of Hg<SUP>2+</SUP> exposure due to the isomerization of imine and preferential metal bonding of two dithiocarbonate groups regardless of the main structure of rhodamine. The sensors exhibited the reversible and reproducible performance for Hg<SUP>2+</SUP> sensing.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Dithiocarbonate group contributes to Hg sensing of new rhodamine sensor. </LI> <LI> Cooperative metal binding of proximal groups are discussed. </LI> <LI> Sensing properties are compared by association constants. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

An ‘OFF–ON’ fluorescent chemosensor based on rhodamine 6G-2-chloronicotinaldehyde for the detection of Al³⁺ ions: Part II

Jeong, Jong Woo,Rao, Boddu Ananda,Lee, Jae-Young,Hwang, Ji-Yong,Son, Young-A Elsevier 2016 Sensors and actuators. B, Chemical Vol.227 No.-

<P><B>Abstract</B></P> <P>A novel, optical rhodamine-2-chloronicotinaldehyde-type chemosensor (<B>R6CN</B>) was designed, synthesized and characterized as a reversible switch. <B>R6CN</B> displayed high selectivity toward Al<SUP>3+</SUP> from various metal ions, including Al<SUP>3+</SUP>, Li<SUP>+</SUP>, Na<SUP>+</SUP>, K<SUP>+</SUP>, Cs<SUP>+</SUP>, Mg<SUP>2+</SUP>, Ca<SUP>2+</SUP>, Fe<SUP>2+</SUP>, Co<SUP>2+</SUP>, Ni<SUP>2+</SUP>, Cu<SUP>2+</SUP>, Zn<SUP>2+</SUP>, Ag<SUP>+</SUP>, Cd<SUP>2+</SUP>, Hg<SUP>2+</SUP>, Pb<SUP>2+</SUP> and the resultant complex [<B>R6CN</B>-Al<SUP>3+</SUP>]. The ring-opening mechanism of the rhodamine spirolactam was induced by Al<SUP>3+</SUP> binding, and the 1:1 stoichiometric structure between <B>R6CN</B> and Al<SUP>3+</SUP> was adequately supported by the Job-plot evaluation, optical titration, FT-IR and <SUP>1</SUP>H NMR results. Theoretical calculations and modeling simulations were performed using <I>Material Studio 4.3 suite</I> (<I>VAMP</I>), and the results supported the formation of a 1:1 complex between <B>R6CN</B> and Al<SUP>3+</SUP>. The fluorescence quantum yield of <B>R6CN</B>-Al<SUP>3+</SUP> (<I>Φ</I> <SUB>f</SUB> =92.33%) was very high compared to that of the bare ligand. The detection limit for Al<SUP>3+</SUP> was 4.28×10<SUP>−9</SUP> M, and a significant color change from almost colorless to pale-pink occurred in the presence of Al<SUP>3+</SUP>. In turn, the <B>R6CN</B>-Al<SUP>3+</SUP> complex acted as a selective chemosensor toward N<SUB>3</SUB> <SUP>−</SUP> among various anions, including F<SUP>−</SUP>, Cl<SUP>−</SUP>, Br<SUP>−</SUP>, I<SUP>−</SUP>, NO<SUB>3</SUB> <SUP>−</SUP>, CH<SUB>3</SUB>COO<SUP>−</SUP>, ClO<SUB>4</SUB> <SUP>−</SUP>, CN<SUP>−</SUP>, SCN<SUP>−</SUP>, HSO<SUB>4</SUB> <SUP>−</SUP>, HPO<SUB>4</SUB> <SUP>−</SUP> and PF<SUB>6</SUB> <SUP>−</SUP>, in acetonitrile media. Moreover, the <B>R6CN</B>-Al<SUP>3+</SUP> complex also exhibited a high selectivity and sensitivity toward the azide anion upon the addition of Al<SUP>3+</SUP>, and the color reversed back to colorless when the two ions were present together in solution. At last, <B>R6CN</B> was productively applied to the PEGDMA polymer to sense Al<SUP>3+</SUP> ions, which was analyzed using FT-IR, fluorescence confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) images.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A novel rhodamine-2-chloronicotinaldehyde (<B>R6CN</B>) chemosensor was designed and synthesized in high yield. </LI> <LI> Rhodamine-2-chloronicotinaldehyde (<B>R6CN</B>) exhibits very high selectivity toward Al<SUP>3+</SUP> ions and reversible “turn-off” fluorescence was achieved using the azide (N<SUB>3</SUB> <SUP>−</SUP>) anion. </LI> <LI> The complex between the chemosensor <B>R6CN</B> and Al<SUP>3+</SUP> was found to have a 1:1 ratio by titration. </LI> <LI> The structure of the <B>R6CN</B>-Al<SUP>3+</SUP> complex was determined using <SUP>1</SUP>H NMR and FT-IR titration and molecular modeling studies. </LI> <LI> <B>R6CN</B> was mixed with PEGDMA polymer for chemosensing the Al<SUP>3+</SUP> ion with reversibility by N<SUB>3</SUB> <SUP>−</SUP> ion. </LI> </UL> </P>

Through-bond energy transfer based dyad and triad shape fluorescence ''OFF-ON-OFF'' probes for Hg²⁺ ions and their application in live HeLa cells and Zebrafish

Kim, H.S.,Angupillai, S.,Jeong, Y.M.,Park, J.S.,Kim, C.H.,Son, Y.A. Elsevier Sequoia 2017 Sensors and actuators. B Chemical Vol.240 No.-

Two novel through-bond energy transfer (TBET) based naphthoquinone derivatives, R1 and R2, have been designed and synthesized with characteristics of a dyad (rhodamine-quinone) and a triad (rhodamine-quinone-rhodamine), respectively. Probes R1 and R2 selectively sense Hg<SUP>2+</SUP> ions over other common interference metal ions in aqueous-methanol medium with a broad pH range (6.0-8.0). By the combination of dual functions, (i.e., fluorescence off-on (rhodamine) and TBET off-on (through a conjugation linker) processes), the proposed TBET-probes exhibit very large pseudo-Stokes shifts, with a wavelength difference ~210nm, and high energy transfer efficiency for the detection of Hg<SUP>2+</SUP> with a detection limit of 41nM. The fluorescence intensity of the triad (R2) is nearly 2 orders of magnitude greater than that of the dyad R1 due to the existence of two rhodamine fragments. The OFF-ON fluorescence effect of the TBET cassettes regains the ON-OFF mode by subsequent addition of the I<SUP>-</SUP> ion. The optical restoring behavior of the R1/R2-Hg<SUP>2+</SUP> complex with I<SUP>-</SUP> could be potentially be applied as an INHIBIT molecular logic gate with the combination of YES and NOT functions. Finally, the Hg<SUP>2+</SUP> ion sensing ability of TBET probes R1 and R2 was utilized in a HeLa cell imaging application, and the probe R1 was used to monitor the Hg<SUP>2+</SUP> ion in live zebrafish.