Water
·
2020
·Vol. 12
·期 11
·3251
·
IF 2.544
Heejun Kang,Saerom Park,Bokjin Lee,Jaehwan Ahn,Seogku Kim
Recently, environmental pollution from microplastics (MPs) has become a significant reason for increasing the number of studies to develop analysis methods. The Nile red staining method (NR-S), which is staining polymer particles with Nile red (NR) dye, has been widely used for the analysis of MPs in environmental samples. However, this method has several limitations, as it is difficult to stain MPs covered with organic matter residues. In this study, we modified the NR-S method into an NR plate method (NR-P), where the plate is coated with NR instead of staining MPs directly. The optimum concentration of NR solution was obtained (1000 mg/L), and the effectiveness of the NR-P method for the analysis of MPs was assessed using different types (polypropylene, polyethylene, polyethylene terephthalate, and polystyrene), sizes (100–1000 µm), and shapes (sphere, fiber, film, and flake) of plastic materials. The NR-P method demonstrated improved resolution in the overall types, shapes, and sizes of MPs and was better than the control (without NR plate method) and NR-S method. In particular, the NR-P method can effectively observe MPs covered with organic matter, which was a major limitation of the NR-S method. Finally, MPs in sewage field samples were analyzed by the NR-P method with an accuracy of 78% confirmed by FT-IR. We demonstrated that this method is a convenient and efficient alternative for identifying MPs, even for field samples.Keywords:microplastics;Nile red staining;Nile red plate;UV light
研究领域:
环境科学
·
分析化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COASTAL RESEARCH
·
2020
·
IF 0.793
Gao Nan,Kong Xiangfeng,Lv Hongmin,Sun Zhongliang,Liu Yan
Gao, N.; Kong, X.; Lv, H.; Sun, Z., and Liu, Y., 2020. An effective fluorescent probe method applied in the analysis of microplastics. In: Liu, X. and Zhao, L. (eds.), Today's Modern Coastal Society: Technical and Sociological Aspects of Coastal Research. Journal of Coastal Research , Special Issue No. 111, pp. 70–77. Coconut Creek (Florida), ISSN 0749-0208. Microplastic pollution has received global attention because of the durable hazards it brings to the environment. Methods used to analyze microplastics are mainly limited by laboratory conditions, instruments, and labor. This study investigated a method to analyze microplastics, and in situ verification was carried out to prove the feasibility of the technique. The method employed the fluorescent probe Nile red, followed by identification with Raman spectroscopy. Six kinds of common polymers were tested to verify the optimal operating condition of the technique. Possible fluorescence interference that obscured the Raman signal was excluded through verification of the Laman spectrum. Using this method, four kinds of polymers were found in Qingdao coastal waters, and the size of microplastics was confirmed. The results demonstrate that the fluorescent probe technique may offer considerable application in further monitoring studies to obtain reliable microplastic data.
研究领域:
环境科学
·
分析化学
✓ 已验证
DOI
高影响因子
MARINE POLLUTION BULLETIN
·
2021
·
IF 5.553
Chun Wang,Lijuan Jiang,Ruiqing Liu,Meilin He,Xiaoyu Cui,Changhai Wang
Monitoring microplastics in the environment based on the Nile red staining protocol has proven to be a newly emerged method in several instances. However, the methodology is still having the limitations of susceptibility, indiscrimination, and complexity, etc. The objectives of this paper are to explore the effects of wavelength, temperature, H 2 O 2 and NaCl addition, plastic property, and fluorescent index on the Nile red staining in microplastics analysis and propose solutions to these inadequacies. Sample co-stained with H 2 O 2 (ω final = 10%) and NaCl (ω final = 8.8%) will lower the fluorescence intensity of biogenic materials and reduce their interferences. Based on the fluorescence color and intensity of fused fluorographs, the combined fluorescent index for twelve microplastics was significantly different, thus could be preliminarily distinguished. An elevated staining temperature is propitious to fluorescent tagging with Nile Red. Finally, an improved protocol was proposed, which made the methodology streamlined in microplastics analysis.
研究领域:
环境科学
·
分析化学
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2015
·
IF 2.752
Jiao Wang,Xiao Chen,Wanling Cui,Sijing Yi
pH-responsive vesicles have been prepared from the mixture of 1-(10-(4-formyl-phenoxy) decyl)-pyridinium (FDP) or 1-methyl-3-(10-(4-formyl-phenoxy) decyl) imidazolium (FDI) with 1-octyl amine at a molar ratio of 1:1 in alkaline aqueous solutions. Their structures and morphologies were characterized by transmission electron microscopy with sample preparations by negative staining or freeze-fracture. Basically, the spherical unilamellar vesicles were formed with the mean diameters respectively of about 71 and 107 nm for two supra-amphiphile systems, which were based on the formation of dynamic imine bonds between amine and FDP (i-FDP) or FDI (i-FDI). The loading and release studies of a fluorophore, Nile red (NR), demonstrated the capabilities of these vesicles to encapsulate NR and a rapid release at low pH environment. The vesicles from i-FDP behaved relatively more sensitive to acidic environment than those from i-FDI. The dynamic transitions of supra-amphiphiles were characterized by nuclear magnetic resonance or fluorescence emission spectroscopy measurements. A lower critical micelle concentration and a higher aldehyde conversion efficiency of i-FDI than those of i-FDP were observed. The characteristics of facile formation, fast dissociation, and switchable morphologies of studied systems should be referable for designing novel smart supra-amphiphile systems with potential applications as controlled drug delivery systems.
研究领域:
生物化学
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材料科学
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药物递送
✓ 已验证
产品关联
DOI
高影响因子
PHOTOCHEMISTRY AND PHOTOBIOLOGY
·
2011
·Vol. 87
·期 3
·646-652
·
IF 2.679
LiLi Yu,Cong Lv,LiZhu Wu,ChenHo Tung,WanLiang Lv,ZhongJin Li,XinJing Tang
We intend to form photosensitive block copolymer micelles for controllable release of encapsulated substances. Here, we designed and synthesized a new photocleavable cross-linker (2-nitrophenyl ethylene glycol dimethacrylate) for methyl methacrylate (MMA) atom transfer radical polymerization. Four different ratios (0:1, 1:26, 1:16, 1:8.8) of the photocleavable cross-linker to MMA monomer were used and four block copolymers (P0, P1, P2, P3) were synthesized with PEO-Br as the macroinitiator. Gel permeation chromatography and 1 H NMR studies showed that linear polymer molecules could be cross-linked by the photocleavable linker. The fluorescence studies of the encapsulated Nile Red (NR) showed that there were lower critical micelle concentrations for the polymer P1, P2 and P3 than polymer P0. And dynamic light scattering and SEM confirmed the formation of polymer micelles. Photolysis experiments demonstrated that NR encapsulated in the polymer micelles could be released upon UV irradiation (365 nm, 11 mW cm −2 ) due to the breakage of the photocleavable linker and the generation of more hydrophilic acid moieties, which destabilized polymer micelles. Our study shows a new strategy for the possibility of photocontrollable drug release for hydrophobic drugs.
研究领域:
材料科学
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药物递送
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 135
·期 35
·46675
·
IF 1.901
Yeqing Dong,Xiaoyan Ma,Haohui Huo,Qilu Zhang,Fengjin Qu,Fang Chen
A novel series of quadruple responsive copolymers, poly(ethylene glycol)- ss -[poly(dimethylaminoethyl methacrylate)- co -poly(2-nitrobenzyl methacrylate)] [PEG- ss -(PDMAEMA- co -PNBM)], were synthesized via atom transfer radical polymerization mediated by home-made PEG-based macro-initiator labeled with disulfides. The obtained copolymers could self-assemble in aqueous solution forming micelles with the disulfide bridge linking the hydrophilic coronas (PEG) and the hydrophobic cores (PDMAEMA- co -PNBM). Investigation on the resulted micelles indicated that the micelles could respond to various stimuli, that is, temperature, pH, the presence of dithiothreitol (DTT), and UV irradiation. Moreover, the responsive behavior of the micelles depends on the type of stimuli, that is, temperature change causes size change of the micelles, while UV irradiation leads to dissolution of the self-assembled structures. Such stimulus-dependent responsive behavior could be applied in smart materials that deal with multi-tasks or in the construction of complex logic gate. The potential application of the multi-responsive micelles in cargo release system was also evaluated using Nile Red (NR) as model molecule. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46675.
研究领域:
材料科学
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药物递送
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2020
·
IF 3.99
Chenglin Luo,Bang Yu,Qi Qi,Yifang Mi,Zhihai Cao,Qinmin Cui,Zujin Zhao
Magnetic-fluorescent bifunctional nanoparticles (NPs) have been widely used in biomedical applications. In this work, magnetic-fluorescent bifunctional NPs (P/Fe 3 O 4 /Nile Red NPs) were achieved via a facile miniemulsion polymerization. The morphologies and properties of the as-prepared P/Fe 3 O 4 /Nile Red NPs were systematically characterized. High-efficiency encapsulation of iron oxide (Fe 3 O 4 ) and Nile Red in polymer matrix endowed the resultant P/Fe 3 O 4 /Nile Red NPs with prominent superparamagnetism and bright fluorescence. Furthermore, the cell viability experiment revealed the low cytotoxicity of P/Fe 3 O 4 /Nile Red NPs, indicating the P/Fe 3 O 4 /Nile Red NPs are suitable for cell imaging . This work provides a one-pot facile method to fabricate magnetic-fluorescent bifunctional NPs.
研究领域:
生物医学工程
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材料科学
·
细胞生物学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2020
·
IF 7.1
Md. Rajibur Rahaman Khan,Seungtaek Oh,Giheon Choi,Hwa Sung Lee
We design and develop a low-cost, highly-sensitive, wide dynamic range interdigitated capacitor (IDC) lactate sensor based on the capacitance variation principle. We use Nile red, which has solvatochromic properties and this dye containing sensing membrane deposit into the interdigitated electrode (IDE) to prepare an IDC lactate sensing element. We apply the capacitance-to-phase conversion technique to detect lactate concentrations between 100 nM and 1 M by altering the dielectric constant of the membrane. As a result, the capacitance of the IDC sensing element change, introducing a phase shift and producing an output voltage. The sensitivity of the IDC sensing element is 11.28 ns/decade and offer a linear sensing response over a wide dynamic range with a correlation coefficient of R 2 ≈ 0.998. The IDC sensing element also offers an extremely stable response with a fast response time of 1.02 s and fast recovery time of 1.3 s. The relative standard deviation of the stability is 0.024. The proposed IDC lactate sensing element show/exhibit an excellent sensing performance compare to the other lactate-sensors.
研究领域:
生物医学工程
·
传感技术
·
分析化学
✓ 已验证
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2015
·
IF 2.353
Meiduo Zhang,Dehua Li,Yi He,Guang Wang
An amphiphilic naphthopyran derivative (DSNP) with negative-charged di-sulfatoethoxy was first designed and synthesized. DSNP was used to prepare the LBL self-assembly films with cationic quaternized poly(4-vinylpyridine) (P4VPQ). The multilayer assembly process was monitored via UV–Vis spectra and the DSNP displayed a significant slow fading rate in film. In addition, DSNP was also used as the light-responsive group to fabricate light-responsive micelles with polyethylene glycol–triethylamine bromide (PEG–NEt 3 ). The photoisomerization of naphthopyran moieties can rapidly and reversibly tune the disassembly and re-assembly of the micelles. The changes of fluorescent spectra of Nile Red (NR) in water solution of polymeric micelles demonstrated that the polymeric micelle can be used as nanocarriers to encapsulate, release and re-encapsulate guest solutes on demand controlling of light irradiation. The results indicate that the amphiphilic naphthopyran can be used in both optical-switches and biomedical area for drug delivery.
研究领域:
材料科学
·
生物医药
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 138
·期 24
·50580
·
IF 3.125
Dandan Zhang,Jilu Li,Hongmei Xie,Aoqi Zhu,Yiting Xu,Birong Zeng,Weiang Luo,Lizong Dai
Compared with the single polymer micelle system, the polyion complex micellar system is consisted of two or more polymers with different composition, which has more flexible structural adjustment and better performance, making them widely used in drug control release. In this work, two azobenzene-based amphiphilic copolymers P (MMA- co -PEGMA- co -NIPAM- co -HAZOMA) with ionized carboxyl and P (MMA- co -PEGMA- co -NIPAM- co -NNAZOMA) with protonated tertiary amine group were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. We studied self-assembled behavior of polymers and multi-component polymers, including their multiple responsiveness and the encapsulation, controlled release properties of polyion complex micelle. Light, pH, temperature, and reduction responsiveness of three micelles were investigated by UV–vis spectroscopy, transmission electron microscope (TEM), and dynamic light scattering. Compared to RCP 1, and RCP 2, RCP 1/RCP 2 micelle can release Nile red in both acidic and alkaline environment. When temperature reached critical solution temperature, RCP 1/RCP 2 micelle would release Nile red faster. Polyion complex micelle had better release performance compared to single micelles at the same environment, and could release in a wider range pH, making it had more potential applications in biological science field.
研究领域:
高分子化学
·
药物传递系统
·
生物材料
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry B
·
2021
·Vol. 9
·期 10
·2524-2531
·
IF 6.331
Wei Ma,Bing Xu,Ru Sun,Yu-Jie Xu,Jian-Feng Ge
To develop a new class of neutral fluorescent dyes with mitochondrial staining capacity, a series of functional dyes were obtained from Nile Red (2a–e) and coumarin (3a–e) with different amide compounds via Suzuki coupling reactions. The Nile Red derivatives (2a–e) emitted red fluorescence (590–660 nm) and coumarin derivatives (3a–e) showed blue emission (455–490 nm) in organic solvents. In addition, they exhibited high fluorescence quantum yields (0.27–0.98) in organic solvents and excellent photostability (>92%). Moreover, all of them possessed low cytotoxicity. More importantly, Nile Red borate (2) and coumarin borate (3) only accumulated in lipid droplets, while after being modified by different amide compounds, dyes 2a–e and 3a–e could successfully target mitochondria in HeLa cancer cells via confocal fluorescence experiments. This work provides a new strategy for the design of neutral cellular probes for mitochondrial staining.
研究领域:
细胞生物学
·
医学化学
·
分子影像学
✓ 已验证
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2021
·Vol. 46
·期 3
·1399-1408
·
IF 3.591
Wanbing Li,Haibo Zhang,Zhaolan Zhai,Xujuan Huang,Shibin Shang,Zhanqian Song
Novel ‘bola’ rosin-based photo-responsive amphiphilic polymers PMPn (n = 17, 34, or 69) were synthesized using poly(ethylene glycol) (PEG) as a double hydrophilic head and N-azobenzenemaleimidepimaric acid (AZOMPA) as a hydrophobic tail. The relatively fixed position of the rigid group of rosin can reduce the entanglement of PEG chains and enhance the influence of the cis-isomerization of azobenzene on the volume and polarity of the entire polymer. Consequently, all polymers with different chain lengths show an extremely high photoresponsive efficiency and various morphological changes. For the PMP17 and PMP34 assemblies, collapse of the sphere micelles takes place upon UV irradiation and this process is reversible; by contrast, the PMP69 assemblies transformed from worm micelles to large spherical micelles, cloud-like micelles, large composite micelles and irregular spherical micelles. Subsequently, encapsulation of the hydrophobic fluorescent probe Nile red and as well as its release from the loaded probes triggered by UV irradiation were evaluated. The UV irradiation experiments demonstrated the photoresponsive behavior of the “bola” amphiphilic polymers PMPn containing the rigid rosin-based azobenzene group, giving an elegant strategy for design of stimuli-responsive materials.
研究领域:
材料科学
·
高分子化学
·
光化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）