Rhodamine Derivative Functionalized Magnetic Nanoplatform for Cu<sup>2+</sup> Sensing and Removal

Wang, Jiaxin; Wang, Shuhan; Tian, Wanqing; Yao, Dong; Sun, Lining; Shi, Liyi; Liu, Jinliang

doi:https://doi.org/10.1155/2018/7049675

Journal of Nanomaterials

On this page

Abstract Introduction Results Conclusions Data Availability Conflicts of Interest Acknowledgments References Copyright Related Articles

Research Article | Open Access

Volume 2018 | Article ID 7049675 | https://doi.org/10.1155/2018/7049675

Rhodamine Derivative Functionalized Magnetic Nanoplatform for Cu²⁺ Sensing and Removal

Jiaxin Wang,¹Shuhan Wang,¹Wanqing Tian,²Dong Yao,²Lining Sun,¹Liyi Shi,¹and Jinliang Liu¹

Academic Editor: Xuping Sun

Received29 Mar 2018

Accepted06 May 2018

Published10 Jun 2018

Abstract

Pollution caused by copper is one of the key factors of environment contamination. As one of the heavy metals, copper is hard to decompose in nature; the biological enrichment of which may lead to severe damage to health. Cu²⁺ detection, thus, possesses a bright application prospect both in environment protection and in human health. In this paper, a dual-functional fluorescence-magnetic composite nanoplatform has been designed to sensitively detect, meanwhile, capture, and remove Cu²⁺ in the solution of water and ethanol (1 : 1, v/v). The core-shell structure nanoparticle synthesized by using Fe₃O₄ as core and SiO₂ as shell is covalently bonded with rhodamine derivatives on the silica layer to construct the nanoplatform. The emission is increased upon the addition of Cu²⁺, showing fluorescence turn on effect for the detection, and the limit of detection is as low as 1.68 nM. Meanwhile, Cu²⁺ ions are captured by the coordination with rhodamine derivatives and can be removed with the help of magnetic field.

1. Introduction

With the increasing development of social productivity, copper pollution as a representative of heavy metal contamination is getting worse. Copper dust, which is made by the weathering of the rocks, mining, metallurgy, and machine process, will result in pollution of air, water, and soil [1–3]. Meanwhile, copper is hard to decompose in nature, and the resulting enrichment through food chain may lead to severe damage to health [4, 5]. As an essential trace element, copper ions, if in improper dose [6], are likely to cause human poisoning, and illness involves the nervous system, digestive system, cardiovascular system, endocrine system, and so on, among which are known to the majority including Alzheimer’s disease, hepatic cirrhosis, leucoderma, and skeleton deformity [7–10]. Therefore, the development of new methods for the detection and removal of copper ions in the environment has attracted a lot of research interests in the past decades.

There are many techniques at present to detect Cu²⁺, such as atomic absorption spectrometry (AAS), inductively coupled plasma atomic emission spectrometry (ICP-AES), and inductively coupled plasma mass spectrometry (ICP-MS) [11–13]. But difficulties still exist in trace analysis, due to the limited sensitivity and detection limits (LOD) of machine. In addition, expensive test cost, large amounts of time in sample preparation, and inconvenience for on-site analysis are the stumbling blocks to Cu²⁺ detection, both in life and environment. As an effective approach, the florescence method has advantages of technical simplicity, high sensitivity, fast response time, and nondestructive imaging [14–16]. In terms of florescence determination, the key procedure is to design and synthesize fluorescent probes to detect metal ions or biomolecules by monitoring luminescence quenching [17–20] or enhancement phenomenon [21–23] upon the interaction with testing samples. Lots of fluorescent probes have been developed for detection of Cu²⁺ ions with high sensitivity and selectivity [24–26]. Among these reports, rhodamine compounds have shown significant advantages over some traditional fluorophores due to their attractive feature such as high photostability, wide wavelength range, and high fluorescence quantum yield and thus become an extensive research topic in the field of chemistry and biology [27–30]. However, fluorescent probes with single structure often suffer from some drawbacks, such as low detect efficiencies, separation difficulties, and secondary pollution to environment. Nanoplatform which combined the inorganic-organic composite together fills the gap by its prominent advantages in complementation and cooperatives in multifunction. As for inorganic composite, magnetic nanoparticles provide us an environmental friendly way of separation and recycle [31–33]. There are different ways in ion detection and removal based on the functionalized magnetic nanoplatform. One of the common ways is adsorption. For instance, Cu²⁺ ions are absorbed by hydroxyl groups from β-cyclodextrin and silane [34]. Another method of ion capture is coordination; for example, 8-hydroxyquinoline-2-carboxylic acid is adopted as chelator to coordinate with copper ions [35].

As one of the famous fluorescent probes, rhodamine derivatives have advantages on high absorbance, improved fluorescence quantum yield, and better photostability. Superparamagnetic nanomaterial is suitable for magnetic separation and fast enrichment. In this work, we have designed a core-shell-structured nanoplatform, in which Fe₃O₄ is core, SiO₂ is shell, and rhodamine derivatives are loaded on the layer of SiO₂. The synthesized hybrid can realize the fluorescence turn on effect for the Cu²⁺ detection and Cu²⁺ removal with the help of external magnetic field.

2. Experimental Section

2.1. Materials

1-Octadecene (ODE, technical grade, 90%), oleic acid (OA, technical grade, 90%), IGEPAL CO-520, and tetraethyl orthosilicate (TEOS, GC, ≥99%) were purchased from Sigma-Aldrich Co. Ltd. (China). Sodium oleate (CP), n-Hexane (AR, 97%), ammonia solution (AR), and salicylaldehyde were obtained from Shanghai Aladdin Chemistry Co. Ltd. (Shanghai, China). Hydrazine hydrate (85%), rhodamine B, and (3-isocyanatopropyl)triethoxysilane (GR, 95%) were purchased from J&K Technology Co. Ltd. Toluene (AR), iron (III) chloride hexahydrate (AR), and anhydrous ethanol (99.7%, AR) were obtained from Sinopharm Chemical Reagent Co., China. All the agents above were used without further purification. Aqueous solution of different ions, such as Cu²⁺, K⁺, Ba²⁺, Co²⁺, Ca²⁺, Na⁺, Mn²⁺, Mg²⁺, Ni²⁺, and Hg⁺, was prepared, respectively, from its chloride salts. Water used during the experiments was deionized water.

2.2. Preparation of Fe₃O₄@SiO₂

Fe₃O₄ was synthesized through pyrolysis method according to the previous report [36] with some modification. 40 mmol of FeCl₃·6H₂O and 40 mmol of sodium oleate were dispersed into 80 mL of ethanol. Then, the resulted solution was mixed with 60 mL of deionized water and 140 mL of n-hexane and kept in 70°C for 4 h. After that, 30 mL of deionized water was then added to wash the product. At last, the oil phase was gathered and dried overnight. Next, 36 g of the resulting iron oleat complex was dissolved in 20 mmol of OA and 200 g of ODE; the mixture was reacted at 320°C for 30 min under Ar. After cooling at room temperature, the solid product was collected and washed with 20 mL of n-hexane for 3 times. Finally, the nanocrystals were dispersed in n-hexane (30 mg/mL) for storage.

Reversed-phase microemulsion method was used in forming silica layer outside of the Fe₃O₄. 250 μL of Fe₃O₄ dispersion was diluted with 10 mL of n-hexane. 50 μL of CO-520 was added while vigorously stirring, then kept at the same condition continuously for 30 min. Next, 2 μL of TEOS was added slowly. Afterwards, 10 μL of ammonia solution was added and the mixture was stirred continuously for 20 h. The resulting products were washed using ethanol as precipitant via centrifugal separation for 3 times. At last, Fe₃O₄@SiO₂ was obtained and dispersed in 5 mL of ethanol at 4°C.

2.3. Preparation of Fe₃O₄@SiO₂@P

The rhodamine derivative (P for short) was synthesized according to our previous article [37]. 60 mg of Fe₃O₄@SiO₂ nanoparticles was redispersed in 20 mL of toluene, and then the solution was heated to 80°C. 20 μL of (3-isocyanatopropyl)triethoxysilane was added by drops, and the temperature was kept at 110°C for 12 h. After that, P (120 mg) distributed in 1 mL of toluene was injected into the reactant rapidly and then, kept at 110°C for another 12 h. After cooling down to room temperature, Fe₃O₄@SiO₂@P was collected via centrifugation and washed with alcohol for three times. Finally, Fe₃O₄@SiO₂@P was dispersed in 5 mL of ethanol and sealed for storage at 4°C for further use.

2.4. Characterization

The morphology features of nanoparticles were observed by transmission electron microscope (TEM, JEM-200CX) at 200 kV. Vibrating sample magnetometer (VSM, 7407; lakeshore) was used for evaluating the magnetic properties at room temperature. Fourier transform infrared (FTIR, AVATAR370, Nicolet) spectroscopy was to analyze functional groups from synthesized materials. Structure analysis of organic molecules was performed by Fourier superconducting nuclear magnetic resonance spectrometer (AVANCE 500 MHz, BRUKER), using tetramethylsilane (TMS) as an internal standard. To detect the actual ion concentrations, inductively coupled plasma atomic emission spectroscopy (ICP-AES, HORIBA JOBIN YVONSAS) was employed. Fluorescent properties were determined by a LS-55 spectrophotometer. The excitation wavelength was 520 nm, and the emissions were collected from 470 to 750 nm. All the measurements mentioned above were conducted at room temperature.

2.5. Cu²⁺ Response and Removal

A stock solution of Fe₃O₄@SiO₂@P (10 mg/mL) was prepared in the solution of water and ethanol (1 : 1, v/v). Stock solutions of the metal ions (0.1 M) were prepared in deionized water. Titration experiments were performed by adding Cu²⁺ solution incrementally to a solution of Fe₃O₄@SiO₂@P (2.5 mL). For the selectivity experiments, the test samples were prepared by adding appropriate amounts (100 equiv.) of metal ion solution to 2.5 mL of a solution of Fe₃O₄@SiO₂@P. In competition experiments, Cu²⁺ was added to the solutions containing Fe₃O₄@SiO₂@P and other metal ions of interest. In Cu²⁺ removal experiments (three parallels), Cu²⁺ (1 mL, 0.1 M) was added in Fe₃O₄@SiO₂@P (2.5 mL) and dispersed evenly. Under magnet treatment, the resulted supernate was collected, respectively, after 5 min and 10 min. All solutions were stirred for 3 min at room temperature and then used for the spectroscopic test.

3. Results and Discussions

3.1. Morphology and Structure Characterization

As illustrated in Scheme 1, Fe₃O₄ nanoparticle was designed as the core, and its intrinsic magnetism was the critical factor for separation and removal of Cu²⁺ with external magnetic field. As Figure 1(a) showed, Fe₃O₄ was uniform and monodisperse and the measured diameter was 9.88 ± 0.79 nm. By utilizing reversed-phase microemulsion method, solid silica was coated on the surface of Fe₃O₄ via hydrolysis-condensation reaction of TEOS. The obtained Fe₃O₄@SiO₂ possessed regular morphology with the average diameter of 21.63 ± 1.57 nm, and the average thickness of silica layer was about 5 nm measured from the TEM images (Figure 1(b)). The magnetic nanoplatform Fe₃O₄@SiO₂@P was finally achieved by the nucleophilic addition reaction between the amino group of (3-isocyanatopropyl)triethoxysilane and the hydroxyl group of P. Some aggregation appeared after loading of P (Figure 1(c)); this is mainly because of the hydrophobic property of the organic probe molecule P. The saturated magnetization of Fe₃O₄@SiO₂ was 43.4 emu/g, as shown in Figure 1(d). After combining with organic probe molecules, the saturated magnetization of the hybrid probe was decreased to 22.6 emu/g. It is suggested that the outer nonmagnetic composite leads to the decrease of maximum saturation magnetizations.

(a)

(b)

(c)

(d)

Fourier transform infrared spectroscopy (FTIR) of Fe₃O₄@SiO₂ and Fe₃O₄@SiO₂@P was carried out in order to testify the successful loading of P. As Figure 2 showed, FTIR of Fe₃O₄@SiO₂ exhibited two characteristic bands of silica layer. Peak at 1094 cm⁻¹ was attributed to Si-O-Si symmetric stretching vibrations, and peak at 562 cm⁻¹ was assigned to Si-O symmetric stretching vibrations. The spectrum of Fe₃O₄@SiO₂@P showed C=C symmetric stretching vibrations at 1616 cm⁻¹, 1514 cm⁻¹, and 1461 cm⁻¹, which belonged to benzene ring. Also, C=O stretching vibration at 1715 cm⁻¹ was appeared; thus, it could be concluded that covalent bonding existed between P and silica.

3.1.1. Sensing and Capture of Cu²⁺

The ion-responsive mechanism was achieved due to the well-known equilibrium between the nonfluorescent spirolactam and the fluorescent ring-opened amide of rhodamine. The emission spectrum of Fe₃O₄@SiO₂@P upon various concentrations of Cu²⁺ is shown in Figure 3(a). Under the excitation at 520 nm, the emission bands centered at 552 nm appear and the intensities increase evidently with the Cu²⁺ concentration increased. This indicates that the ring-open process of the rhodamine B unit in P happened. A linear correlation between the emission intensity and concentration of Cu²⁺ in the range of 0–25 nM can be observed (Figure 3(b)). The limit of detection (LOD) was calculated as low as 1.68 nM by the following formula LOD = 3S₀/S (where S₀ is the standard deviation of the blank measurements, S is the slope of the calibration curve, and 3 is the factor at the 99% confidence level), suggesting the high sensitivity of the nanoplatform for detecting Cu²⁺.

(a)

(b)

Benefits from the intrinsic structure of P and the magnetic properties of Fe₃O₄, the nanoplatform can realize the fluorescent detection of Cu²⁺ with naked eyes and removal of Cu²⁺ with the help of magnetic field. As shown in Figure 4(a), before the addition of Cu²⁺, the hybrid nanoplatform was light brown color and nonflorescent. When Cu²⁺ was added, the hydrazide group and O-acyl hydroxylamines bonded with Cu²⁺, and thus led to the opening of the spirolactam ring in P molecule. The resulting conjugate π-bond facilitates the enhancement of florescence intensity at 550 nm. Also, photoinduced electron transfer (PET) was blocked; thus, the solution of fluorescence probe turned into pink color [38–40]. The Cu²⁺ removal effect of the nanoplatform was shown in Figure 4(a) (E, F). We can see that, after a few seconds, the nanoplatform together with Cu²⁺ gathered to the side of cuvette under magnetic felid treatment. The removal efficiency of Cu²⁺ was 75% calculated from ICP-AES results. Furthermore, the selective experiments were done to demonstrate the nanoplatform which can detect Cu²⁺ exclusively over other metal ions. As shown in Figure 4(b), there was nearly no color change upon the introduction of other metal ions, including K⁺, Ba²⁺, Co²⁺, Ca²⁺, Na⁺, Mn²⁺, Mg²⁺, Ni²⁺, and Hg²⁺. Additionally, competition experiments were further carried out by adding Cu²⁺ to the solutions containing both nanoplatform and the metal ions of interest. As shown in Figure 4(c), these coexistent ions had negligible interference on Cu²⁺ sensing; even the competitive ions were present at high concentrations.

(a)

(b)

(c)

4. Conclusions

In brief, a dual-functional hybrid nanoplatform Fe₃O₄@SiO₂@P had been successfully prepared. In this nanoplatform, the Fe₃O₄ as the core endowes it with magnetism; SiO₂ as one thin layer bridges the inorganic-organic composites together; rhodamine derivative P is designed for fluorescent sensing of Cu²⁺. Benefits from the intrinsic structure of P and the magnetic properties of Fe₃O₄, the nanoplatform can realize the fluorescent detection of Cu²⁺ with naked eyes and removal of Cu²⁺ with the help of magnetic field. This nanoplatform was featured on simple operation, uniform particle size, structural stability, and excellent magnetic responsibility and thus can be used for the cell imaging of Cu²⁺ or removal of Cu²⁺ from the environmental pollution.

Data Availability

The data used to support the findings of this study are available from the corresponding author upon request.

Conflicts of Interest

The authors declare that they have no conflicts of interest.

Acknowledgments

The authors are grateful for the financial support from the National Natural Science Foundation of China (Grant nos. 21201117 and 21231004) and Medical Research Project of Jiangsu Provincial Commission of Health and Family Planning (no. Z201624).

References

S. Dragovic and N. Mihailovic, “Analysis of mosses and topsoils for detecting sources of heavy metal pollution: multivariate and enrichment factor analysis,” Environmental Monitoring and Assessment, vol. 157, no. 1–4, pp. 383–390, 2009.
View at: Publisher Site | Google Scholar
M. Huber, A. Welker, and B. Helmreich, “Critical review of heavy metal pollution of traffic area runoff: occurrence, influencing factors, and partitioning,” Science of the Total Environment, vol. 541, pp. 895–919, 2016.
View at: Publisher Site | Google Scholar
Q. Ding, G. Cheng, Y. Wang, and D. F. Zhuang, “Effects of natural factors on the spatial distribution of heavy metals in soils surrounding mining regions,” Science of the Total Environment, vol. 578, pp. 577–585, 2017.
View at: Publisher Site | Google Scholar
D. V. Nesterkova, E. L. Vorobeichik, and I. S. Reznichenko, “The effect of heavy metals on the soil-earthworm-European mole food chain under the conditions of environmental pollution caused by the emissions of a copper smelting plant,” Contemporary Problems of Ecology, vol. 7, no. 5, pp. 587–596, 2014.
View at: Publisher Site | Google Scholar
R. Dallinger and W. Wieser, “The flow of copper through a terrestrial food chain,” Oecologia, vol. 30, no. 3, pp. 253–264, 1977.
View at: Publisher Site | Google Scholar
J. R. Prohaska, “Impact of copper deficiency in humans,” Annals of the New York Academy of Sciences, vol. 1314, no. 1, pp. 1–5, 2014.
View at: Publisher Site | Google Scholar
K. Jomova, S. Baros, and M. Valko, “Redox active metal-induced oxidative stress in biological systems,” Transition Metal Chemistry, vol. 37, no. 2, pp. 127–134, 2012.
View at: Publisher Site | Google Scholar
N. F. Suttle, “Copper imbalances in ruminants and humans: unexpected common ground,” Advances in Nutrition, vol. 3, no. 5, pp. 666–674, 2012.
View at: Publisher Site | Google Scholar
K. Y. Djoko, B. M. Paterson, P. S. Donnelly, and A. G. McEwan, “Antimicrobial effects of copper(II) bis(thiosemicarbazonato) complexes provide new insight into their biochemical mode of action,” Metallomics, vol. 6, no. 4, pp. 854–863, 2014.
View at: Publisher Site | Google Scholar
C. Wijmenga and L. W. J. Klomp, “Molecular regulation of copper excretion in the liver,” Proceedings of the Nutrition Society, vol. 63, no. 1, pp. 31–39, 2004.
View at: Publisher Site | Google Scholar
A. Zhuravlev, A. Zacharia, M. Arabadzhi, C. Turetta, G. Cozzi, and C. Barbante, “Comparison of analytical methods: ICP-QMS, ICP-SFMS and FF-ET-AAS for the determination of V, Mn, Ni, Cu, As, Sr, Mo, Cd and Pb in ground natural waters,” International Journal of Environmental Analytical Chemistry, vol. 96, no. 4, pp. 332–352, 2016.
View at: Publisher Site | Google Scholar
Y. G. Tu, Y. Zhao, M. S. Xu, X. Li, and H. Y. Du, “Simultaneous determination of 20 inorganic elements in preserved egg prepared with different metal ions by ICP-AES,” Food Analytical Methods, vol. 6, no. 2, pp. 667–676, 2013.
View at: Publisher Site | Google Scholar
Z. H. Li, J. X. Chen, M. S. Liu, and Y. L. Yang, “Supramolecular solvent-based microextraction of copper and lead in water samples prior to reacting with synthesized Schiff base by flame atomic absorption spectrometry determination,” Analytical Methods, vol. 6, no. 7, pp. 2294–2298, 2014.
View at: Publisher Site | Google Scholar
Y. Zhou, Z. Xu, and J. Yoon, “Fluorescent and colorimetric chemosensors for detection of nucleotides, FAD and NADH: highlighted research during 2004–2010,” Chemical Society Reviews, vol. 40, no. 5, pp. 2222–2235, 2011.
View at: Publisher Site | Google Scholar
H. N. Kim, Z. Q. Guo, W. H. Zhu, J. Yoon, and H. Tian, “Recent progress on polymer-based fluorescent and colorimetric chemosensors,” Chemical Society Reviews, vol. 40, no. 1, pp. 79–93, 2011.
View at: Publisher Site | Google Scholar
H. N. Kim, W. X. Ren, J. S. Kim, and J. Yoon, “Fluorescent and colorimetric sensors for detection of lead, cadmium, and mercury ions,” Chemical Society Reviews, vol. 41, no. 8, pp. 3210–3244, 2012.
View at: Publisher Site | Google Scholar
L. Yang, D. N. Liu, S. Hao et al., “Topotactic conversion of α-Fe₂O₃ nanowires into FeP as a superior fluorosensor for nucleic acid detection: insights from experiment and theory,” Analytical Chemistry, vol. 89, no. 4, pp. 2191–2195, 2017.
View at: Publisher Site | Google Scholar
J. Q. Tian, N. Y. Cheng, Q. Liu, W. Xing, and X. P. Sun, “Cobalt phosphide nanowires: efficient nanostructures for fluorescence sensing of biomolecules and photocatalytic evolution of dihydrogen from water under visible light,” Angewandte Chemie International Edition, vol. 54, no. 18, pp. 5493–5497, 2015.
View at: Publisher Site | Google Scholar
W. B. Lu, X. Y. Qin, S. Liu et al., “Economical, green synthesis of fluorescent carbon nanoparticles and their use as probes for sensitive and selective detection of mercury(II) ions,” Analytical Chemistry, vol. 84, no. 12, pp. 5351–5357, 2012.
View at: Publisher Site | Google Scholar
S. Liu, J. Q. Tian, L. Wang et al., “Hydrothermal treatment of grass: a low-cost, green route to nitrogen-doped, carbon-rich, photoluminescent polymer nanodots as an effective fluorescent sensing platform for label-free detection of Cu(II) ions,” Advanced Materials, vol. 24, no. 15, pp. 2037–2041, 2012.
View at: Publisher Site | Google Scholar
F. Y. Wu, S. W. Bae, and J. I. Hong, “A selective fluorescent sensor for Pb(II) in water,” Tetrahedron Letters, vol. 47, no. 50, pp. 8851–8854, 2006.
View at: Publisher Site | Google Scholar
K. M. Lee, X. Chen, W. Fang, J. M. Kim, and J. Yoon, “A dual colorimetric and fluorometric sensor for lead ion based on conjugated polydiacetylenes,” Macromolecular Rapid Communications, vol. 32, no. 6, pp. 497–500, 2011.
View at: Publisher Site | Google Scholar
X. Peng, J. Du, J. Fan et al., “A selective fluorescent sensor for imaging Cd²⁺ in living cells,” Journal of the American Chemical Society, vol. 129, no. 6, pp. 1500-1501, 2007.
View at: Publisher Site | Google Scholar
W. J. Lu, Y. F. Gao, Y. Jiao, S. M. Shuang, C. Z. Li, and C. Dong, “Carbon nano-dots as a fluorescent and colorimetric dual-readout probe for the detection of arginine and Cu²⁺ and its logic gate operation,” Nanoscale, vol. 9, no. 32, pp. 11545–11552, 2017.
View at: Publisher Site | Google Scholar
Q. Shu, M. L. Liu, H. Ouyang, and Z. F. Fu, “Label-free fluorescent immunoassay for Cu²⁺ ion detection based on UV degradation of immunocomplex and metal ion chelates,” Nanoscale, vol. 9, no. 34, pp. 12302–12306, 2017.
View at: Publisher Site | Google Scholar
Z. Liu, W. He, M. S. Pei, and G. Y. Zhang, “A fluorescent sensor with a detection level of pM for Cd²⁺ and nM for Cu²⁺ based on different mechanisms,” Chemical Communications, vol. 51, no. 75, pp. 14227–14230, 2015.
View at: Publisher Site | Google Scholar
Y. L. Huang, A. S. Walker, and E. W. Miller, “A photostable silicon rhodamine platform for optical voltage sensing,” Journal of the American Chemical Society, vol. 137, no. 33, pp. 10767–10776, 2015.
View at: Publisher Site | Google Scholar
V. P. Boyarskiy, V. N. Belov, R. Medda, B. Hein, M. Bossi, and S. W. Hell, “Photostable, amino reactive and water-soluble fluorescent labels based on sulfonated rhodamine with a rigidized xanthene fragment,” Chemistry A European Journal, vol. 14, no. 6, pp. 1784–1792, 2008.
View at: Publisher Site | Google Scholar
J. Liu, Y. Q. Sung, H. X. Zhang, H. P. Shi, Y. W. Shi, and W. Guo, “Sulfone-rhodamines: a new class of near-infrared fluorescent dyes for bioimaging,” ACS Applied Materials & Interfaces, vol. 8, no. 35, pp. 22953–22962, 2016.
View at: Publisher Site | Google Scholar
P. Hanczyc and L. Sznitko, “Laser-induced population inversion in rhodamine 6G for lysozyme oligomer detection,” Biochemistry, vol. 56, no. 22, pp. 2762–2765, 2017.
View at: Publisher Site | Google Scholar
L. Y. Zhang, Q. Zhao, Z. Liang et al., “Synthesis of adenosine functionalized metal immobilized magnetic nanoparticles for highly selective and sensitive enrichment of phosphopeptides,” Chemical Communications, vol. 48, no. 50, pp. 6274–6276, 2012.
View at: Publisher Site | Google Scholar
H. Li, Y. H. Shan, L. Z. Qiao, A. Dou, X. Z. Shi, and G. W. Xu, “Facile synthesis of Boronate-decorated Polyethyleneimine-grafted hybrid magnetic nanoparticles for the highly selective enrichment of modified nucleosides and ribosylated metabolites,” Analytical Chemistry, vol. 85, no. 23, pp. 11585–11592, 2013.
View at: Publisher Site | Google Scholar
Z. Y. Hu, L. Zhao, H. Y. Zhang, Y. Zhang, R. A. Wu, and H. F. Zou, “The on-bead digestion of protein corona on nanoparticles by trypsin immobilized on the magnetic nanoparticle,” Journal of Chromatography A, vol. 1334, pp. 55–63, 2014.
View at: Publisher Site | Google Scholar
Y. Zhang, W. Wang, Q. Li, Q. Yang, Y. Li, and J. Du, “Colorimetric magnetic microspheres as chemosensor for Cu²⁺ prepared from adamantane-modified rhodamine and β-cyclodextrin-modified Fe₃O₄@SiO2 via host–guest interaction,” Talanta, vol. 141, pp. 33–40, 2015.
View at: Publisher Site | Google Scholar
Z. Cui, W. Bu, W. Fan et al., “Sensitive imaging and effective capture of Cu²⁺: towards highly efficient theranostics of Alzheimer’s disease,” Biomaterials, vol. 104, pp. 158–167, 2016.
View at: Publisher Site | Google Scholar
J. Park, K. An, Y. Hwang et al., “Ultra-large-scale syntheses of monodisperse nanocrystals,” Nature Materials, vol. 3, no. 12, pp. 891–895, 2004.
View at: Publisher Site | Google Scholar
X. Meng, Y. Xu, J. Liu, L. Sun, and L. Shi, “A new fluorescent rhodamine B derivative as an “off–on” chemosensor for Cu²⁺with high selectivity and sensitivity,” Analytical Methods, vol. 8, no. 5, pp. 1044–1051, 2016.
View at: Publisher Site | Google Scholar
V. Dujols, F. Ford, and A. W. Czarnik, “A long-wavelength fluorescent chemodosimeter selective for Cu(II) ion in water,” Journal of the American Chemical Society, vol. 119, no. 31, pp. 7386-7387, 1997.
View at: Publisher Site | Google Scholar
J. Li, Q. Hu, Y. Zeng, X. Yu, and Z. Pan, “Rhodamine-based fluorescent probes for cations,” Process In Chemistry, vol. 24, no. 5, pp. 823–833, 2012.
View at: Google Scholar
Y. Yuan, M. Tian, F. Feng, S. Meng, and Y. Bai, “Rhodamine-based cations fluorescent probes,” Process In Chemistry, vol. 22, no. 10, pp. 1929–1939, 2010.
View at: Google Scholar

Copyright

Copyright © 2018 Jiaxin Wang et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

PDF Download Citation

Download other formats

Order printed copies

Views

1197

Downloads

1027

Citations

Journal of Nanomaterials

Rhodamine Derivative Functionalized Magnetic Nanoplatform for Cu2+ Sensing and Removal

Abstract

1. Introduction

2. Experimental Section

2.1. Materials

2.2. Preparation of Fe3O4@SiO2

2.3. Preparation of Fe3O4@SiO2@P

2.4. Characterization

2.5. Cu2+ Response and Removal

3. Results and Discussions

3.1. Morphology and Structure Characterization

3.1.1. Sensing and Capture of Cu2+

4. Conclusions

Data Availability

Conflicts of Interest

Acknowledgments

References

Copyright

Rhodamine Derivative Functionalized Magnetic Nanoplatform for Cu²⁺ Sensing and Removal

2.2. Preparation of Fe₃O₄@SiO₂

2.3. Preparation of Fe₃O₄@SiO₂@P

2.5. Cu²⁺ Response and Removal

3.1.1. Sensing and Capture of Cu²⁺