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Lu P, Jiang J, Liu C, Okuda S, Itoh H, Okamoto K, Suzuki M, Nagata K. Molecular mechanism of Fe 3+ binding inhibition to Vibrio metschnikovii ferric ion-binding protein, FbpA, by rosmarinic acid and its hydrolysate, danshensu. Protein Sci 2024; 33:e4881. [PMID: 38143427 PMCID: PMC10804667 DOI: 10.1002/pro.4881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 12/12/2023] [Accepted: 12/20/2023] [Indexed: 12/26/2023]
Abstract
Global warming has increased the growth of pathogenic Vibrio bacteria, which can cause foodborne illnesses and death. Vibrio bacteria require iron for growth and survival. They utilize a ferric ion-binding protein (FbpA) to bind and transport Fe3+ into the cell. FbpA from Vibrio metschnikovii (Vm) is a potential target for inhibiting its growth. Rosmarinic acid (RA) can block the binding of VmFbpA to Fe3+ ; however, the molecular mechanism of Fe3+ binding and RA inhibition to VmFbpA is unclear. In this study, we used x-ray crystallography to determine the Fe3+ -binding mode of VmFbpA and the mechanism of RA inhibition. The structures revealed that in the Fe3+ bound form, Fe3+ was coordinated to VmFbpA by two Tyr residues, two HCO3 - ions, and two water molecules in a six-coordinated geometry. In contrast, in the inhibitor bound form, RA was initially bound to VmFbpA following gel filtration purification, but it was hydrolyzed to danshensu (DSS), which occupied the binding site as shown in an electron density map and reverse phase chromatography (RPC) analysis. Both RA and DSS exhibited a stronger binding affinity to VmFbpA, higher Fe3+ reduction capacity, and more potent bacteriostatic effect on V. metschnikovii compared with caffeic acid (CA), another hydrolysis product of RA. These results provide insight into the mechanism of iron acquisition by V. metschnikovii and inhibition by RA and DSS. Our findings offer clues on the development of effective strategies to prevent Vibrio infections.
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Affiliation(s)
- Peng Lu
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life ScienceThe University of TokyoTokyoJapan
| | - Jinyan Jiang
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life ScienceThe University of TokyoTokyoJapan
| | - Chang Liu
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life ScienceThe University of TokyoTokyoJapan
| | - Suguru Okuda
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life ScienceThe University of TokyoTokyoJapan
| | - Hideaki Itoh
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life ScienceThe University of TokyoTokyoJapan
| | - Ken Okamoto
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life ScienceThe University of TokyoTokyoJapan
| | - Michio Suzuki
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life ScienceThe University of TokyoTokyoJapan
| | - Koji Nagata
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life ScienceThe University of TokyoTokyoJapan
- Agricultural Bioinformatics Research Unit, Graduate School of Agricultural and Life ScienceThe University of TokyoTokyoJapan
- Research Center for Food Safety, Graduate School of Agricultural and Life ScienceThe University of TokyoTokyoJapan
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Pandey N, Jyoti, Singh M, Dwivedi P, Sahoo SC, Mishra BB. Click chemistry inspired synthesis of andrographolide triazolyl conjugates for effective fluorescent sensing of ferric ions. Nat Prod Res 2021; 36:5438-5448. [PMID: 34905436 DOI: 10.1080/14786419.2021.2013837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
The naturally occurring compound andrographolide 1 was used as a substrate for the synthesis of a novel terminal alkyne 3 which on copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction with azides 4a-l, 7 and 9 furnished a series of regioselective andrographolide triazolyl conjugates 5a-l, 8 and 10, respectively. A free glycoconjugate 6 was also prepared by selective deprotection of compound 5i in good yield. All the compounds were characterized by absorbance, FT-IR, NMR, and HR-MS analyses. The triazolyl conjugate 8 was further investigated as a probe for selective detection of Fe3+ ion in matrix. The mode of attachment of Fe3+ ion to the compound 8 was established by absorbance, fluorescence, infrared (IR), and nuclear magnetic resonance (NMR) spectroscopy, and high resolution mass-spectrometry (HR-MS). The logic gate circuits were constructed for the probe 8 and ethylenediaminetetraacetic acid (EDTA). The environmental perspective of probe 8 was investigated in real water samples.
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Affiliation(s)
- Nishant Pandey
- Center of Innovative and Applied Bioprocessing (CIAB), Mohali, Punjab, India.,Department of Chemistry, Faculty of Science, Panjab University, Chandigarh, India
| | - Jyoti
- Center of Innovative and Applied Bioprocessing (CIAB), Mohali, Punjab, India.,Department of Chemistry, Faculty of Science, Panjab University, Chandigarh, India
| | - Mangat Singh
- Center of Innovative and Applied Bioprocessing (CIAB), Mohali, Punjab, India.,Department of Chemistry, Faculty of Science, Panjab University, Chandigarh, India
| | - Pratibha Dwivedi
- Center of Innovative and Applied Bioprocessing (CIAB), Mohali, Punjab, India
| | - Subash C Sahoo
- Department of Chemistry, Faculty of Science, Panjab University, Chandigarh, India
| | - Bhuwan B Mishra
- Center of Innovative and Applied Bioprocessing (CIAB), Mohali, Punjab, India
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3
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Zhan Y, Shen X, Chen M, Yang K, Xie H. Bioleaching of tellurium from mine tailings by indigenous Acidithiobacillus ferrooxidans. Lett Appl Microbiol 2021; 75:1076-1083. [PMID: 34586632 DOI: 10.1111/lam.13569] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 09/02/2021] [Accepted: 09/12/2021] [Indexed: 11/28/2022]
Abstract
Tellurium (Te) is a scarce and valuable metalloid, which can be found in some mine tailings. In this work, an indigenous Acidithiobacillus ferrooxidans strain was used to leach Te from mine tailings collected in the Shimian Te mine region, China. Under the optimized conditions of initial pH of 2·0, pulp density of 4% and temperature of 30°C, 47·77% of Te can be dissolved after 24 days of bioleaching. The leaching of Te by different systems such as bioleaching, Ferric ion (Fe(III)) leaching and acid leaching was compared. The results showed that the leaching behaviour of Te is similar to that of sulphur in sulphide minerals, that is, Fe(III) first oxidizes telluride (Te(-II)) in minerals to elemental Te, and then elemental Te can be oxidized by bacteria to Te(IV) and Te(VI). Besides, it was also showed by scanning electron microscope observation and Fourier transform infrared spectroscopy analysis of the ore sample before and after bioleaching that some bedded structure covered on the surface of the ore after bioleaching acting as a reaction compartment, and the changing of active groups indicated a possible attachment between bacteria and ore. There is an indirect mechanism involved in bioleaching of Te.
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Affiliation(s)
- Y Zhan
- College of Ecology and Environment, Chengdu University of Technology, Chengdu, P.R. China
| | - X Shen
- College of Ecology and Environment, Chengdu University of Technology, Chengdu, P.R. China
| | - M Chen
- College of Ecology and Environment, Chengdu University of Technology, Chengdu, P.R. China
| | - K Yang
- College of Ecology and Environment, Chengdu University of Technology, Chengdu, P.R. China
| | - H Xie
- College of Ecology and Environment, Chengdu University of Technology, Chengdu, P.R. China
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Oh WD, Ho YC, Mohamad M, Ho CD, Ravi R, Lim JW. Systematic Performance Comparison of Fe 3+/Fe 0/Peroxymonosulfate and Fe 3+/Fe 0/Peroxydisulfate Systems for Organics Removal. Materials (Basel) 2021; 14:5284. [PMID: 34576510 PMCID: PMC8468805 DOI: 10.3390/ma14185284] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 08/11/2021] [Accepted: 08/16/2021] [Indexed: 11/16/2022]
Abstract
Activated zero-valent iron (Ac-ZVI) coupled with Fe3+ was employed to activate peroxymonosulfate (PMS) and peroxydisulfate (PDS) for acid orange 7 (AO7) removal. Fe3+ was used to promote Fe2+ liberation from Ac-ZVI as an active species for reactive oxygen species (ROS) generation. The factors affecting AO7 degradation, namely, the Ac-ZVI:Fe3+ ratio, PMS/PDS dosage, and pH, were compared. In both PMS and PDS systems, the AO7 degradation rate increased gradually with increasing Fe3+ concentration at fixed Ac-ZVI loading due to the Fe3+-promoted liberation of Fe2+ from Ac-ZVI. The AO7 degradation rate increased with increasing PMS/PDS dosage due to the greater amount of ROS generated. The degradation rate in the PDS system decreased while the degradation rate in the PMS system increased with increasing pH due to the difference in the PDS and PMS activation mechanisms. On the basis of the radical scavenging study, sulfate radical was identified as the dominant ROS in both systems. The physicochemical properties of pristine and used Ac-ZVI were characterized, indicating that the used Ac-ZVI had an increased BET specific surface area due to the formation of Fe2O3 nanoparticles during PMS/PDS activation. Nevertheless, both systems displayed good reusability and stability for at least three cycles, indicating that the systems are promising for pollutant removal.
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Affiliation(s)
- Wen-Da Oh
- School of Chemical Sciences, Universiti Sains Malaysia, Gelugor 11800, Penang, Malaysia
| | - Yeek-Chia Ho
- Civil and Environmental Engineering Department, Centre for Urban Resource Sustainability, Institute of Self-Sustainable Building, Universiti Teknologi PETRONAS, Seri Iskandar 32610, Perak Darul Ridzuan, Malaysia
| | - Mardawani Mohamad
- Faculty of Bioengineering and Technology, Universiti Malaysia Kelantan, Jeli Campus, Jeli 17600, Kelantan, Malaysia;
| | - Chii-Dong Ho
- Department of Chemical and Materials Engineering, Tamkang University, Tamsui, New Taipei 251, Taiwan;
| | - Rajiv Ravi
- School of Applied Sciences, Faculty of Integrated Life Science, Quest International University, Ipoh 30250, Perak, Malaysia;
| | - Jun-Wei Lim
- Department of Fundamental and Applied Sciences, HICoE-Centre for Biofuel and Biochemical Research, Institute of Self-Sustainable Building, Universiti Teknologi PETRONAS, Seri Iskandar 32610, Perak Darul Ridzuan, Malaysia;
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5
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Moriiwa Y, Morikawa G, Okazawa K, Yanagida A. Optimization of Analytical Procedure for In-hospital Rapid Quantification of Serum Level of Favipiravir in the Pharmacological Treatment of COVID-19. ANAL SCI 2021; 37:1301-1304. [PMID: 33612558 DOI: 10.2116/analsci.21n004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
An in-hospital rapid method for quantifying the serum level of favipiravir (FPV) in the pharmacological treatment of COVID-19 was developed by an appropriate combination of a solid-phase extraction treatment and a reversed-phase HPLC/UV detection system. The quantification method was well-validated and applied to measuring the serum FPV level in a clinical practice at a general hospital that accepts COVID-19 patients. Furthermore, an analysis of data from our preliminary interaction analysis revealed, for the first time, that FPV selectively forms complexes with ferric (Fe3+) and cupric (Cu2+) ions.
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Affiliation(s)
- Yukiko Moriiwa
- Department of Biomedical Analysis, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
| | - Go Morikawa
- Department of Pharmacy, Hokushin General Hospital
| | | | - Akio Yanagida
- Department of Biomedical Analysis, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
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Liu H, Pu Y, Tong T, Zhu X, Sun B, Zhang X. Photochemical Generation of Methyl Chloride from Humic Aicd: Impacts of Precursor Concentration, Solution pH, Solution Salinity and Ferric Ion. Int J Environ Res Public Health 2020; 17:ijerph17020503. [PMID: 31941122 PMCID: PMC7013589 DOI: 10.3390/ijerph17020503] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 01/02/2020] [Accepted: 01/09/2020] [Indexed: 12/02/2022]
Abstract
Methyl chloride (CH3Cl) is presently understood to arise from biotic and abiotic processes in marine systems. However, the production of CH3Cl via photochemical processes has not been well studied. Here, we reported the production of CH3Cl from humic acid (HA) in sunlit saline water and the effects of the concentration of HA, chloride ions, ferric ions and pH were investigated. HA in aqueous chloride solutions or natural seawater were irradiated under an artificial light, and the amounts of CH3Cl were determined using a purge-and-trap and gas chromatography-mass spectrometry. CH3Cl was generated upon irradiation and its amount increased with increasing irradiation time and the light intensity. The formation of CH3Cl increased with an increase of HA concentration ranging from 2 mg L−1 to 20 mg L−1 and chloride ion concentration ranging from 0.02 mol L−1 to 0.5 mol L−1. The photochemical production of CH3Cl was pH-dependent, with the highest amount of CH3Cl generating near neutral conditions. Additionally, the generation of CH3Cl was inhibited by ferric ions. Finally, natural coastal seawater was irradiated under artificial light and the concentration of CH3Cl rose significantly. Our results suggest that the photochemical process of HA may be a source of CH3Cl in the marine environment.
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Mochizuki R, Higashi K, Okamoto Y, Abe H, Iwase H, Toida T. Detection of Selenocyanate in Biological Samples by HPLC with Fluorescence Detection Using König Reaction. Chem Pharm Bull (Tokyo) 2019; 67:884-887. [PMID: 31366837 DOI: 10.1248/cpb.c19-00277] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We developed a simple and sensitive HPLC method for the determination of selenocyanate (SeCN-). The König reaction, which is generally used for the determination of cyanide and thiocyanate, was applied for the post-column detection, and using barbituric acid as a fluorogenic reagent made it possible to detect SeCN- with high sensitivity. The limits of detection (LOD) and quantification (LOQ) were 73.5 fmol and 245.1 fmol, respectively. Subsequently, the amounts of SeCN- in human blood and in cultured cell samples were analyzed, and no SeCN- was detected in human whole blood. Interestingly, we have found that some of the spiked SeCN- decomposed to cyanide in human whole blood. Ascorbic acid suppressed the decomposition of SeCN- to cyanide by reducing the ferric ion, which is typically involved in SeCN- decomposition. Then, SeCN- was detected in cultured HEK293 cells exposed to selenite. The established HPLC method with fluorescence detection of SeCN- is useful for investigating small amounts of SeCN- in biological samples.
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Affiliation(s)
- Ryu Mochizuki
- Graduate School of Pharmaceutical Sciences, Chiba University
| | - Kyohei Higashi
- Faculty of Pharmaceutical Sciences, Tokyo University of Science
| | - Yusuke Okamoto
- Graduate School of Pharmaceutical Sciences, Chiba University
| | - Hiroko Abe
- Graduate School of Medicine, Chiba University
| | | | - Toshihiko Toida
- Graduate School of Pharmaceutical Sciences, Chiba University
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8
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Guo X, Niu C, Wu Y, Liang X. Application of an M13 bacteriophage displaying tyrosine on the surface for detection of Fe(3+) and Fe(2+) ions. Virol Sin 2015; 30:410-6. [PMID: 26676941 DOI: 10.1007/s12250-015-3651-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 12/03/2015] [Indexed: 10/22/2022] Open
Abstract
Ferric and ferrous ion plays critical roles in bioprocesses, their influences in many fields have not been fully explored due to the lack of methods for quantification of ferric and ferrous ions in biological system or complex matrix. In this study, an M13 bacteriophage (phage) was engineered for use as a sensor for ferric and ferrous ions via the display of a tyrosine residue on the P8 coat protein. The interaction between the specific phenol group of tyrosine and Fe(3+) / Fe(2+) was used as the sensor. Transmission electron microscopy showed aggregation of the tyrosine-displaying phages after incubation with Fe(3+) and Fe(2+). The aggregated phages infected the host bacterium inefficiently. This phenomenon could be utilized for detection of ferric and ferrous ions. For ferric ions, a calibration curve ranging from 200 nmol/L to 8 μmol/L with a detection limit of 58 nmol/L was acquired. For ferrous ions, a calibration curve ranging from 800 nmol/L to 8 μmol/L with a detection limit of 641.7 nmol/L was acquired. The assay was specific for Fe(3+) and Fe(2+) when tested against Ni(2+), Pb(2+), Zn(2+), Mn(2+), Co(2+), Ca(2+), Cu(2+), Cr(3+), Ba(2+), and K(+). The tyrosine displaying phage to Fe(3+) and Fe(2+) interaction would have plenty of room in application to biomaterials and bionanotechnology.
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Villota N, Camarero LM, Lomas JM, Perez-Arce J. The role of iron species on the turbidity of oxidized phenol solutions in a photo-Fenton system. Environ Technol 2015; 36:1855-1863. [PMID: 25652956 DOI: 10.1080/21622515.2015.1013573] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This work aims at establishing the contribution of the iron species to the turbidity of phenol solutions oxidized with photo-Fenton technology. During oxidation, turbidity increases linearly with time till a maximum value, according to a formation rate that shows a dependence of second order with respect to the catalyst concentration. Next, the decrease in turbidity shows the evolution of second-order kinetics, where the kinetics constant is inversely proportional to the dosage of iron, of order 0.7. The concentration of iron species is analysed at the point of maximum turbidity, as a function of the total amount of iron. Then, it is found that using dosages FeT=0-15.0 mg/L, the majority iron species was found to be ferrous ions, indicating that its concentration increases linearly with the dosage of total iron. This result may indicate that the photo-reaction of ferric ion occurs leading to the regeneration of ferrous ion. The results, obtained by operating with initial dosages FeT=15.0 and 25.0 mg/L, suggest that ferrous ion concentration decreases while ferric ion concentration increases in a complementary manner. This fact could be explained as a regeneration cycle of the iron species. The observed turbidity is generated due to the iron being added as a catalyst and the organic matter present in the system. Later, it was found that at the point of maximum turbidity, the concentration of ferrous ions is inversely proportional to the concentration of phenol and its dihydroxylated intermediates.
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Affiliation(s)
- Natalia Villota
- a Department of Chemical and Environmental Engineering , Escuela Universitaria de Ingeniería Vitoria-Gasteiz, University of the Basque Country, UPV/EHU , Nieves Cano, 12, Vitoria-Gasteiz 01006 , Spain
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Tanaka E. Appressorium-mediated penetration of Magnaporthe oryzae and Colletotrichum orbiculare into surface-cross-linked agar media. FEMS Microbiol Lett 2015; 362:fnv066. [PMID: 25877547 DOI: 10.1093/femsle/fnv066] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/09/2015] [Indexed: 12/12/2022] Open
Abstract
Many phytopathogenic fungi form appressoria on some artificial substances. However, it is difficult to induce appressorium-mediated penetration into artificial substances. In the present study, novel artificial agar media were developed to investigate the in vitro penetration process of phytopathogenic fungi. The media contained sodium carboxymethyl cellulose or sodium alginate, and the surfaces were subjected to ionic cross-linking using trivalent metal ions. The hemibiotrophic phytopathogenic fungi, rice blast fungus and cucurbit anthracnose fungus, formed appressoria and penetrated into the surface cross-linked artificial agar media from the base of appressoria. These artificial media appeared to induce fungal infection behaviour that occurred on host plants.
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Affiliation(s)
- Eiji Tanaka
- Ishikawa Prefectural University, Ishikawa 921-8836, Japan
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Chen BY, Kuo CC, Huang YS, Lu ST, Liang FC, Jiang DH. Novel highly selective and reversible chemosensors based on dual-ratiometric fluorescent electrospun nanofibers with pH- and Fe(3+)-modulated multicolor fluorescence emission. ACS Appl Mater Interfaces 2015; 7:2797-2808. [PMID: 25585636 DOI: 10.1021/am508029x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Novel dual-ratiometric fluorescent electrospun (ES) nanofibers featuring high sensitivity for pH and ferric ion (Fe(3+)) were prepared using binary blends of poly(2-hydroxyethyl methacrylate-co-N-methylolacrylamide-co-nitrobenzoxadiazolyl derivative) (poly(HEMA-co-NMA-co-NBD)) and a spirolactam rhodamine derivative (SRhBOH) by employing a single-capillary spinneret. The HEMA, NMA, and NBD moieties were designed to exhibit hydrophilic properties, chemical cross-linking, and fluorescence (fluorescence resonance energy transfer (FRET) donor), respectively. The fluorescence emission of SRhBOH was highly selective for pH and Fe(3+); when SRhBOH detected acidic media and Fe(3+), the spirocyclic form of SRhBOH, which is nonfluorescent, was transformed into the opened cyclic form and exhibited strong fluorescence emission. The emission colors of ES nanofibers in acidic or Fe(3+) aqueous solutions changed from green to red because of FRET from NBD (donor) to SRhBOH (acceptor). The off/on switching of the FRET process was modulated by adjusting the SRhBOH blending ratio, pH, and Fe(3+) concentration. Poly(HEMA-co-NMA-co-NBD) ES fibers blended with 20% SRhBOH showed high sensitivity in sensing Fe(3+) and pH because of the substantial 57 nm red shift in emission as well as substantial reversible dual photoluminescence. The prepared FRET-based dual-ratiometric fluorescent ES nanofibrous membranes can be used as "naked eye" sensors and have potential for application in multifunctional environment sensing devices.
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Affiliation(s)
- Bo-Yu Chen
- Institute of Organic and Polymeric Materials, National Taipei University of Technology , 10608 Taipei, Taiwan
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Zhang J, Yuan Y, Yu ZL, Yu A, Yu SH. Selective detection of ferric ions by blue-green photoluminescent nitrogen-doped phenol formaldehyde resin polymer. Small 2014; 10:3662-3666. [PMID: 24863556 DOI: 10.1002/smll.201303461] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Indexed: 06/03/2023]
Abstract
The smaller, the more fluorescent: The hydrothermal reaction of phenol with hexamethylenetetramine (HMT) leads to two morphologies of phenol formaldehyde resin (PFR), namely, bigger nanoparticles with feeble green fluorescence and smaller amorphous polymers with strong blue-green fluorescence. It reveals that both of them are doped with nitrogen, and the blue-green photoluminescent polymer is confirmed to sense ferric ion (Fe(3+) ) with high selectivity.
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Affiliation(s)
- Jia Zhang
- Division of Nanomaterials and Chemistry, Hefei National Laboratory for Physical Sciences at Microscale, Collaborative Innovation Center of Suzhou Nano Science and Technology, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China
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Abstract
Gap junction blocking agents can inhibit spontaneous discharge frequency in cells. We established a rat model of posttraumatic epilepsy induced using ferric ions. Rats were intraperitoneally injected with carbenoxolone, 20 mg/kg, prior to and 30 minutes after model establishment, once a day for 14 consecutive days. Immunohistochemistry showed glial cell proliferation around a cortical focus and significantly increased connexin expression in posttraumatic epilepsy. However, carbenoxolone pretreatment or treatment significantly reduced connexin expression in the cortex, inhibited glial fibrillary acidic protein expression and ameliorated seizure degree in rats. These findings indicate that large amounts of glial cell proliferation and abnormal gap junction generation play a role in posttraumatic epilepsy, and that carbenoxolone may prevent and treat this disease.
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Affiliation(s)
- Weiguan Chen
- Department of Rehabilitation Medicine, Affiliated Hospital of Nantong University, Nantong 226001, Jiangsu Province, China
| | - Zhiwei Gao
- Department of Neurology, Affiliated Hospital of Nantong University, Nantong 226001, Jiangsu Province, China
| | - Yaohui Ni
- Department of Neurology, Affiliated Hospital of Nantong University, Nantong 226001, Jiangsu Province, China
| | - Zhenxiang Dai
- Department of Neurology, Affiliated Hospital of Nantong University, Nantong 226001, Jiangsu Province, China
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Abstract
This study demonstrated that the bacteria could adsorb Fe3+ and reduce Fe3+ to Fe2+. Iron had significant bacteriostatic effects, which were directly proportional to the iron concentration and under the influence of pH and chelator. It presumed that the inhibition of Fe3+ acts through the formation of hydroxyl free radicals.
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Affiliation(s)
- Hong-Qi Sun
- State Key Laboratory of Microbial Technology , Shandong University, Jinan 250100 , China
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