Colorants最新文献_第7页

Following the Light: Use of Multimodal Imaging and Fiber Optic Spectroscopy to Evaluate Aging in Daylight Fluorescent Artists’ Pigments 跟随光:使用多模态成像和光纤光谱来评估日光荧光艺术家颜料的老化

Colorants Pub Date : 2022-05-23 DOI: 10.3390/colorants1020013

Fiona Beckett, A. Shugar

{"title":"Following the Light: Use of Multimodal Imaging and Fiber Optic Spectroscopy to Evaluate Aging in Daylight Fluorescent Artists’ Pigments","authors":"Fiona Beckett, A. Shugar","doi":"10.3390/colorants1020013","DOIUrl":"https://doi.org/10.3390/colorants1020013","url":null,"abstract":"Daylight fluorescent artists’ colors have been well established as fugitive. Upon exposure to light, these vibrant colors can fade and exhibit color shifts. Artwork containing these fluorescent colorants presents complex challenges for art conservators faced with conserving these inherently problematic materials. This paper examined nine fluorescent colorants obtained from Kremer Pigmente, referred to the previous literature and research, and attempted to quantify the visual and photographic observations of fading and color changes. It provides additional information that could be useful in considering conservation documentation and treatment. Fiber optic spectroscopy using ultraviolet and visible light sources was used to measure the spectral shifts of the colorants before and after exposure to light. The fluorescent colors exhibited alterations in intensity coupled with primary peak shifts in the spectrum corresponding to the optical fading and color shifts. Multimodal imaging was executed to analyze the pigments in different regions of the spectrum before and after aging, which has not been documented before with these fluorescent colorants. Imaging in various regions of the spectrum indicated differences in absorption and reflectance between the pigments as captured by a modified camera. The results were compared to recently published research including the identification of the dyes present in the Kremer line of pigments. Multimodal imaging and fiber optic spectroscopy provided valuable information for future documentation and conservation of artworks containing these colorants. Specifically, these non-invasive techniques provide a method to document and identify the spectral changes between the aged and unaged pigment, graph and predict the direction of overall color change, and provide useful data for establishing future conservation treatment protocols.","PeriodicalId":10539,"journal":{"name":"Colorants","volume":"137 47","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91403164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparison of the In Vitro Photodynamic Activity of the C1α and C1β Anomers of a Glucosylated Boron Dipyrromethene 糖基化硼二硝基甲烷C1α和C1β异头物体外光动力学活性的比较

Colorants Pub Date : 2022-05-02 DOI: 10.3390/colorants1020012

Junlong Xiong, K. Yeung, Clarence T T Wong, W. Fong, D. K. Ng

{"title":"Comparison of the In Vitro Photodynamic Activity of the C1α and C1β Anomers of a Glucosylated Boron Dipyrromethene","authors":"Junlong Xiong, K. Yeung, Clarence T T Wong, W. Fong, D. K. Ng","doi":"10.3390/colorants1020012","DOIUrl":"https://doi.org/10.3390/colorants1020012","url":null,"abstract":"Photodynamic therapy (PDT) is an established treatment modality for a range of superficial and localized cancers. There has been tremendous interest in the development of advanced photosensitizers that exhibit superior photophysical properties, high tumor selectivity, and improved pharmacokinetics. Glucose is one of the well-studied targeting moieties that can deliver various therapeutic agents to cancer cells selectively via the Warburg effect. However, the use of glucosylated photosensitizers for targeted PDT has remained little studied and to the best of our knowledge, the PDT effect of the positional isomers of these conjugates has never been compared. We report herein the preparation and photophysical properties of the C1α and C1β anomers of a glucosylated boron dipyrromethene-based photosensitizer. The cellular uptake and photocytotoxicity of both anomers were also studied and compared using A549 human lung carcinoma cells and HEK293 human embryonic kidney cells. Interestingly, the cellular uptake of the C1α anomer was approximately 2-fold higher than that of the C1β anomer regardless of the cell type and incubation time. The uptake pathway of both anomers was also studied. It was found that they were internalized through energy-dependent receptor/protein-mediated endocytosis rather than the well-known glucose transporters and sodium-driven glucose symporters.","PeriodicalId":10539,"journal":{"name":"Colorants","volume":"37 5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88045655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

The First Century of Successful Applications of Pinacyanol: Some Noteworthy Results Pinacyanol成功应用的一个世纪:一些值得注意的结果

Colorants Pub Date : 2022-04-17 DOI: 10.3390/colorants1020011

S. Shapovalov

引用次数: 3

Nanoencapsulation of Red Bell Pepper Carotenoids: Comparison of Encapsulating Agents in an Emulsion Based System 红甜椒类胡萝卜素的纳米包封:乳液体系中包封剂的比较

Colorants Pub Date : 2022-04-01 DOI: 10.3390/colorants1020009

Nicolly de Lima Petito, Julia Marim Devens, D. Falcão, F. Dantas, T. Passos, Kátia Gomes de Lima Araújo

{"title":"Nanoencapsulation of Red Bell Pepper Carotenoids: Comparison of Encapsulating Agents in an Emulsion Based System","authors":"Nicolly de Lima Petito, Julia Marim Devens, D. Falcão, F. Dantas, T. Passos, Kátia Gomes de Lima Araújo","doi":"10.3390/colorants1020009","DOIUrl":"https://doi.org/10.3390/colorants1020009","url":null,"abstract":"Red bell pepper extract rich in carotenoids was (RBPE) encapsulated with four different encapsulating agents: calcium caseinate (ECC), bovine gelatin (EBG), whey proteins isolate (EWPI), and concentrate (EWPC), aiming to investigate the most effective material to coat and enable the water dispersibility of pigments. Formulations were obtained by the oil in water (O/W) emulsification technique, followed by freeze-drying. Samples were analyzed by encapsulation efficiency, high-performance liquid chromatography (HPLC), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), atomic force microscopy (AFM), thermogravimetric analysis (TGA), dispersion stability, and CIELab. Nanoformulations showed a carotenoid encapsulation efficiency of 54.0% (ECC), 57.6% (EWPI), 56.6 % (EWPC), 64.0 % (EBG). Recovered carotenoid profiles from nanoformulations showed similarity to the RBPE, indicating the efficiency of the encapsulation process. Average particle sizes of approximately 109 nm (ECC), 71 nm (EWPI), 64 nm (EWPC), and 173 nm (EBG) were obtained. AFM revealed that all formulations exhibited spherical forms and a heterogeneous distribution profile. Regarding TGA, formulations presented similar thermal behaviors to and lower decomposition speeds than RBPE, suggesting improved thermal stability. Powder formulations were easily dispersed in water (8 mg/mL) and presented intense color and stability to sedimentation for 48 h. Results indicated that all formulations and the chosen technique efficiently increased carotenoid dispersibility in water, indicating their potential to be applied as natural food pigments.","PeriodicalId":10539,"journal":{"name":"Colorants","volume":"52 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73055001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 8

pH-Dependent Coloring of Combination Effect Pigments with Anthocyanins from Brassica oleracea var. capitata F. rubra 花青素与甘蓝复合效应色素的ph依赖性着色研究

Colorants Pub Date : 2022-04-01 DOI: 10.3390/colorants1020010

O. Çoruh, G. Gündüz, Ü. Çolak, B. Maviş

引用次数: 0

Improving the Dyeing of Polypropylene by Surface Fluorination 聚丙烯表面氟化染色的改进

Colorants Pub Date : 2022-03-29 DOI: 10.3390/colorants1020008

M. Namie, Jae-Ho Kim, S. Yonezawa

引用次数: 2

Stability of Rhodamine Lactone Cycle in Solutions: Chain–Ring Tautomerism, Acid–Base Equilibria, Interaction with Lewis Acids, and Fluorescence 罗丹明内酯循环在溶液中的稳定性:链环互变异构、酸碱平衡、与路易斯酸的相互作用和荧光

Colorants Pub Date : 2022-02-24 DOI: 10.3390/colorants1010006

O. Obukhova, N. Mchedlov-Petrossyan, N. Vodolazkaya, L. Patsenker, A. Doroshenko

{"title":"Stability of Rhodamine Lactone Cycle in Solutions: Chain–Ring Tautomerism, Acid–Base Equilibria, Interaction with Lewis Acids, and Fluorescence","authors":"O. Obukhova, N. Mchedlov-Petrossyan, N. Vodolazkaya, L. Patsenker, A. Doroshenko","doi":"10.3390/colorants1010006","DOIUrl":"https://doi.org/10.3390/colorants1010006","url":null,"abstract":"The equilibrium between different tautomers that can be colored or colorless is an important feature for rhodamine dyes. Presently, this phenomenon is mostly discussed for rhodamine B. Herein, we studied the tautomerism and acid–base dissociation (HR+ ⇄ R + H+) of a set of rhodamines in organic media. Form R is an equilibrium mixture of the colored zwitterion R± and colorless lactone R0. Absorption spectra in 90 mass% aqueous acetone reflects the correlation between the dyes structure and the equilibrium constant, KT = [R0]/[R±]. Increase in the pKa value on transferring from water to organic solvents confirms the highly polar character of the R± tautomer. To reveal the role of the solvent nature, the tautomerism of an asymmetrical rhodamine, 2-(12-(diethyliminio)-2,3,5,6,7,12-hexahydro-1H-chromeno[2,3-f]pyrido[3,2,1-ij]quinolin-9-yl)benzoate, was examined in 14 media. This chain–ring tautomerism is an intramolecular acid–base reaction; the central carbon atom acts as a Lewis acid. The interaction with other Lewis acids, Li+, Ca2+, Mg2+, and La3+, results in rupture of lactone cycle. In polar solvents, lactones undergo photocleavage resulting in formation of highly fluorescent R±, whereas the blue fluorescence and abnormally high Stokes shift in low-polar media may be explained either by another photoreaction or by spiroconjugation and charge transfer in the exited state.","PeriodicalId":10539,"journal":{"name":"Colorants","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83622577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Melanin-Binding Colorants: Updating Molecular Modeling, Staining and Labeling Mechanisms, and Biomedical Perspectives 黑色素结合着色剂:更新分子模型，染色和标记机制，以及生物医学观点

Colorants Pub Date : 2022-02-24 DOI: 10.3390/colorants1010007

J. Stockert, J. Espada, A. Blázquez-Castro

{"title":"Melanin-Binding Colorants: Updating Molecular Modeling, Staining and Labeling Mechanisms, and Biomedical Perspectives","authors":"J. Stockert, J. Espada, A. Blázquez-Castro","doi":"10.3390/colorants1010007","DOIUrl":"https://doi.org/10.3390/colorants1010007","url":null,"abstract":"Melanin and melanoma tumors are two fields of increasing interest in biomedical research. Melanins are ubiquitous biopigments with adaptive value and multiple functions, and occur in the malignant melanoma. Although several chemical structures have been proposed for eumelanin, molecular modeling and orbitals indicate that a planar or spiral benzoquinone-porphycene polymer would be the model that better explains the broad-band light and ultrasound absorption, electric conductivity, and graphite-like organization shown by X-ray crystallography and electron microscopy. Lysosomes and melanosomes are selectively labeled by vital probes, and melanin also binds to metal cations, colorants, and drugs, with important consequences in pharmacology, pathology, and melanoma therapy. In addition to traditional and recent oncologic treatments, photodynamic, photothermal, and ultrasound protocols represent novel modalities for melanoma therapy. Since eumelanin is practically the ideal photothermal and ultrasound sensitizer, the vibrational decay from photo-excited electrons after NIR irradiation, or the electrochemical production of ROS and radicals after ultrasound absorption, induce an efficient heating or oxidative response, resulting in the damage and death of tumor cells. This allows repetitive treatments due to the remaining melanin contained in tumoral melanophages. Given that evolution and prognosis of the advanced melanoma is still a concern, new biophysical procedures based on melanin properties can now be developed and applied.","PeriodicalId":10539,"journal":{"name":"Colorants","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84202297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Pigment Coloration Research Published in the Science Citation Index Expanded from 1990 to 2020: A Systematic Review and Bibliometric Analysis 发表在《科学引文索引》上的色素着色研究从1990年扩展到2020年:系统回顾和文献计量分析

Colorants Pub Date : 2022-02-14 DOI: 10.3390/colorants1010005

M. T. Islam, Mohammad Sahariar Farhan, F. Faiza, A. F. M. F. Halim, A. Sharmin

引用次数: 5

Concentration-Dependent Association of Flavylium Chloride with Differential Hydroxy Moieties in Ethanol 乙醇中氯黄与不同羟基部分的浓度依赖性关联

Colorants Pub Date : 2021-12-23 DOI: 10.3390/colorants1010004

Anthony Pagan, Jong I. Lee, Jeonghee Kang

{"title":"Concentration-Dependent Association of Flavylium Chloride with Differential Hydroxy Moieties in Ethanol","authors":"Anthony Pagan, Jong I. Lee, Jeonghee Kang","doi":"10.3390/colorants1010004","DOIUrl":"https://doi.org/10.3390/colorants1010004","url":null,"abstract":"Flavylium ions (6a–6e) were synthesized using Aldol condensation to compare the spectroscopic properties caused by the different numbers and locations of hydroxy groups on the flavylium cations (AH+). Without the addition of acid, increasing the concentration of flavylium ions to 10 mM in ethanol led to the following observation. The flavylium ions with the least number of OH groups (6a and 6b) showed a change in peak at higher concentrations, whereas 6c and 6d did not show the same degree of change in their 1H-NMR signals. This suggests an equilibrium that shifts the isomers B, CE, and Cz more towards the flavylium ion with more OH groups even at low concentrations. One possibility for the cause of this shift is that the flavylium ions become more stable through aggregation. In addition to the NMR results, the UV measurements confirmed that isomers with fewer OH groups showed a more dramatic shift towards the flavylium ion at higher concentrations. Using modeling data at DFT//B3LYP/6311**G(d) level, the self-association was investigated to show that the hydrogen bonding of OH groups is the main player but cannot stabilize entirely without the presence of the chloride ion in the complex.","PeriodicalId":10539,"journal":{"name":"Colorants","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84882609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0