Dyes and Pigments最新文献

{"title":"Effects of π-bridges on the electrochemical and electrochromic properties of bis(triarylamine)-based aramids","authors":"Sheng-Huei Hsiao ,&nbsp;Yaw-Terng Chern ,&nbsp;Qun Zhang ,&nbsp;Meng-Dong Lee ,&nbsp;Nien-Chen Tsai","doi":"10.1016/j.dyepig.2026.113585","DOIUrl":"10.1016/j.dyepig.2026.113585","url":null,"abstract":"<div><div>Aromatic polyamides (aramids) featuring dual triarylamine cores in the repeating unit were synthesized through phosphorylation polyamidation using 4,4′-oxydibenzoic acid and three bis(triarylamine)-diamine monomers, each with varying aromatic π-bridges, specifically 1,4-phenylene, naphthalene-2,6-diyl, and pyrene-1,6-diyl groups. These aramids demonstrated excellent solubility in polar organic solvents, enabling the formation of flexible and robust films via solution casting. They demonstrated significant thermal stability, characterized by moderate glass transition temperatures (236–262 °C), negligible weight loss below 400 °C, and high char yields (exceeding 60 % at 800 °C in nitrogen). The polymer films displayed reversible redox processes and pronounced color changes during cyclic voltammetry scanning within the range of 0–1.2 V. The structural effects of the aromatic π-bridges between the triarylamine cores on both the oxidation potential and electrochromic stability of the aramids were investigated. Notably, for aramids with greater separation between the triarylamine centers, the oxidation onset potential increased, while electrochromic stability decreased.</div></div>","PeriodicalId":302,"journal":{"name":"Dyes and Pigments","volume":"249 ","pages":"Article 113585"},"PeriodicalIF":4.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146036634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Disclosing the dyeing formulations of weld yellows from 18th-century recipe books with molecular fluorescence","authors":"Paula Nabais ,&nbsp;Mara Espírito Santo ,&nbsp;Mila Crippa ,&nbsp;Natércia Teixeira ,&nbsp;Dominique Cardon","doi":"10.1016/j.dyepig.2026.113590","DOIUrl":"10.1016/j.dyepig.2026.113590","url":null,"abstract":"<div><div>For millennia, organic dyes have been used in artworks such as textiles and have great artistic and historic value. They may provide clues to the understanding of the technology behind an artwork's production. The characterization of natural organic colourants in artworks is still a challenge to this day, and of the natural dyes used in cultural heritage, yellows are some of the most difficult to identify.</div><div>This paper explores the potential of combining molecular fluorescence in the visible range with high-performance liquid chromatography coupled with diode-array detection, to disclose historical dye formulations.</div><div>By analysing historically accurate reconstructions following recipes from two 18th c. French master dyers, Antoine Janot and Paul Gout, it was possible to demonstrate that molecular fluorescence is highly sensitive to the presence of specific dye ingredients and different use of recipes. Luteolin (Lut) and Luteolin 7-<em>O</em>-glucoside (Lut-7-<em>O</em>-glc) were identified as the main compounds, with the first being extracted in higher amounts, especially in Janot's variations. The analytical data demonstrated that molecular fluorescence is very sensitive to recipe differences: the presence of tartar correlated with a higher Lut presence, and the use of lime induced a slight shift in the emission maxima, even without affecting the spectral shape due to the exhaustion of molecules in the dye bath. Moreover, our findings revealed technological insights, showing that Paul Gout's optimized recipes achieved comparable yellow tonality to Janot's using a lower percentage of weld. This will provide key knowledge on the technological processes for dyeing with weld from these 18th c. French masters, while creating a molecular fluorescence database for the analysis of artworks.</div></div>","PeriodicalId":302,"journal":{"name":"Dyes and Pigments","volume":"249 ","pages":"Article 113590"},"PeriodicalIF":4.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146036636","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acylated delphinidin glycosides from red-purple sepals of Aquilegia buergeriana var. oxysepala and violet sepals of A. flabellata var. pumila (Ranunculaceae)","authors":"Qi Qin ,&nbsp;Kohtaro Sugahara ,&nbsp;Takahisa Nakane ,&nbsp;Kazushige Honda ,&nbsp;Fumi Tatsuzawa ,&nbsp;Tsukasa Iwashina ,&nbsp;Takayuki Mizuno","doi":"10.1016/j.dyepig.2026.113567","DOIUrl":"10.1016/j.dyepig.2026.113567","url":null,"abstract":"<div><div><em>Aquilegia buergeriana</em> var. <em>oxysepala</em> and <em>A. flabellata</em> var. <em>pumila</em> are two commonly found <em>Aquilegia</em> species in Japan. To clarify the chemical differences underlying the sepal color difference between the two species, we investigated the pigments in their flowers. A total of seven previously undescribed compounds were isolated from the flowers of <em>A. buergeriana</em> var. <em>oxysepala</em> and <em>A. flabellata</em> var. <em>pumila</em>. One previously undescribed anthocyanin, delphinidin 3-<em>O</em>-(3″-malonylglucopyranoside), together with three known delphinidin glucosides, was isolated and identified from <em>A. buergeriana</em> var. <em>oxysepala</em>, while six previously undescribed compounds were isolated and identified from <em>A. flabellata</em> var. <em>pumila</em>. These included four delphinidin glycosides, one flavonol glycoside, and one <em>C</em>-glycosyl flavone; specifically, delphinidin 3-<em>O</em>-glucopyranoside-7-<em>O</em>-(6″-<em>E</em>-caffeoylglucopyranoside), delphinidin 3-<em>O</em>-(6″-<em>E</em>-caffeoylglucopyranoside)-7-<em>O</em>-(6‴-<em>E</em>-caffeoylglucopyranoside), delphinidin 3-<em>O</em>-(3″,6″-<em>E</em>-dicaffeoylglucopyranoside)-7-<em>O</em>-(6‴-<em>E</em>-caffeoylglucopyranoside), delphinidin 3-<em>O</em>-[3″-<em>O</em>-(1⁗-<em>E</em>-caffeoylglucopyranosyl)-(6→3)-malonyl-(6″-malonylglucopyranoside)-7-<em>O</em>-(6‴-<em>E</em>-caffeoylglucopyranoside), quercetin 3-<em>O</em>-glucopyranoside-7-<em>O</em>-[6''-(4‴-<em>O</em>-glucopyranosyl-<em>E</em>-<em>p</em>-coumaroyl)-glucopyranoside], and luteolin 6-<em>C</em>-[6''-(4‴-<em>O</em>-glucopyranosyl-<em>E</em>-<em>p</em>-coumaroyl)-glucopyranoside]. Seven known phenolics were also found in the flowers of <em>A. flabellata</em> var. <em>pumila</em>.</div><div>The pH of the sepals and petals of both species ranged from 5.6 to 5.8. <em>In vitro</em> sepal color reconstruction experiments showed that the sepal colors of <em>A. buergeriana</em> var. <em>oxysepala</em> and <em>A. flabellata</em> var. <em>pumila</em> could be attributed to their respective major anthocyanins. The violet coloration of <em>A. flabellata</em> var. <em>pumila</em> sepals is primarily due to intramolecular copigmentation rather than intermolecular effects. The main structural difference between these anthocyanins is that those of <em>A. flabellata</em> var. <em>pumila</em> possess a 6-caffeoylglucoside moiety at the 7-position, whereas those of <em>A. buergeriana</em> var. <em>oxysepala</em> do not. Our findings suggest that 7-<em>O</em>-glycosylation and acylation of delphinidin may play an important role in the formation of blue hue in the flower.</div></div>","PeriodicalId":302,"journal":{"name":"Dyes and Pigments","volume":"249 ","pages":"Article 113567"},"PeriodicalIF":4.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146036581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Indolo[3,2-b]indole-based monoboron multi-resonance TADF materials toward high-efficiency green OLEDs","authors":"Zhiyuan Chen ,&nbsp;Tong Li ,&nbsp;Jinyu Song ,&nbsp;Lai Hu ,&nbsp;Songtao Ouyang ,&nbsp;Hongjun Zhu ,&nbsp;Xiao-Chun Hang ,&nbsp;Senqiang Zhu ,&nbsp;Rui Liu","doi":"10.1016/j.dyepig.2026.113627","DOIUrl":"10.1016/j.dyepig.2026.113627","url":null,"abstract":"<div><div>Organic light-emitting diodes (OLEDs) are key candidates for next-generation high-efficiency, high-color-purity display and lighting technologies, with multiple-resonance thermally activated delayed fluorescence (MR-TADF) materials as critical emitters. Developing green MR-TADF emitters with high color purity typically requires multi-boron or strongly π-expanded frameworks. In this work, two MR-TADF emitters, <strong>CzBNIDID</strong> and <strong>CzBNIDID-DPA</strong>, were developed and synthesized by employing the indolo[3,2-b]indole (IDID) donor unit to enable efficient green emission within a minimal monoboron MR architecture. The IDID unit serves as an effective nitrogen-containing donor and provides substantial conjugation extension, enabling narrowband green emission at 522-525 nm. Its rigid fused skeleton forms a large planar framework that suppresses molecular vibrational coupling, resulting in photoluminescence quantum yields above 90%. Devices based on the two IDID-containing emitters deliver external quantum efficiencies up to 18.8 % with only 17.6% efficiency roll-off at 1000 cd m⁻², confirming that effective green MR-TADF performance can be achieved without multi-boron or highly extended MR frameworks. These findings validate the effectiveness of indolo[3,2-b]indole as a robust donor module and provide a promising molecular develop strategy for high-performance green MR-TADF materials.</div></div>","PeriodicalId":302,"journal":{"name":"Dyes and Pigments","volume":"249 ","pages":"Article 113627"},"PeriodicalIF":4.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146184781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-concentration annihilators for efficient green-to-blue photon upconversion and photocatalytic production of hydroxyl radicals","authors":"Zece Zhu ,&nbsp;Runjing Yang ,&nbsp;Ruiqi Mo ,&nbsp;Ze-Yu Zhang ,&nbsp;Di Tian ,&nbsp;Ai-Guo Shen","doi":"10.1016/j.dyepig.2026.113618","DOIUrl":"10.1016/j.dyepig.2026.113618","url":null,"abstract":"<div><div>Triplet-triplet annihilation (TTA) upconversion holds significant potential for enhancing semiconductor photocatalysis by converting low-energy photons into higher-energy emissions. However, the practical application of TTA is often limited by the poor solubility of conventional annihilators, which restricts light absorption and upconversion performance. In this study, a novel annihilator (<strong>DPA1</strong>) based on 9,10-diphenylanthracene (<strong>DPA</strong>) was developed by introducing branched alkyl chains, and diphenylmethane was identified as an optimal high-refractive-index solvent. This combination markedly improved the stability of annihilator solutions at high concentrations. Increasing the annihilator concentration in the TTA system effectively suppressed oxygen-induced triplet quenching and back-energy transfer to the sensitizer, resulting in a lower excitation threshold (<strong><em>I</em></strong>_th) and a higher upconversion efficiency (<em>Ф</em>_UC = 14.3 %), facilitating light energy utilization without deaeration. This optimized upconversion system enabled WO₃ to more efficiently utilize visible light for generating hydroxyl radicals. We anticipate that high-concentration annihilator systems will provide bright upconversion luminescence and find broad applications in photocatalysis, photovoltaics, and related fields.</div></div>","PeriodicalId":302,"journal":{"name":"Dyes and Pigments","volume":"249 ","pages":"Article 113618"},"PeriodicalIF":4.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146090585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fluorescence-based strategies for alkaline phosphatase detection: A comprehensive review","authors":"Roy Merkezoğlu ,&nbsp;Hızır Ali Malkoç ,&nbsp;Mustafa Özyürek","doi":"10.1016/j.dyepig.2026.113586","DOIUrl":"10.1016/j.dyepig.2026.113586","url":null,"abstract":"<div><div>Fluorescence-based probes and sensors have emerged as indispensable tools for the detection of alkaline phosphatase (ALP), a clinically significant enzyme, owing to their high sensitivity, real-time imaging capabilities, and superior spatial resolution. This review examines fluorescence-based ALP detection techniques published between 2020 and 2025 and divides them into three main categories, which are small-molecule fluorogenic probes, nanomaterial-based fluorescent sensors and nucleic acid-assisted hybrid systems. In this context, particular attention is given to the structural evolution of various fluorophore scaffolds and the engineering of molecular dye platforms designed to modulate specific photophysics for enzyme-responsive signaling. By utilizing cutting-edge design components like near-infrared and ratiometric fluorophores, nanoparticle-based signal amplifiers, and deoxyribonucleic acid/ribonucleic acid (DNA/RNA)-mediated amplification circuits (including aptamer and clustered regularly interspaced short palindromic repeats (CRISPR)-driven mechanisms), researchers have improved analytical performance across these platforms. A wide range of applications, such as clinical diagnostics (ultrasensitive serum assays), live-cell and in vivo imaging of enzyme activity, environmental monitoring, and high-throughput screening. These advances have enabled applications ranging from ultrasensitive serum assays to live-cell imaging and portable readouts. This review highlights the increasing significance of fluorescence-based ALP detection in analytical chemistry and biomedicine by showcasing both state-of-the-art probe design and practical deployment. It also explores how current developments are laying the groundwork for next-generation ALP sensors with even higher sensitivity, specificity, and versatility. In addition to summarizing recent reports, we benchmark the 2020–2025 literature against pre-2020 ALP sensing paradigms to delineate genuine step-changes and to highlight persistent limitations that remain unresolved. Lastly, it discusses the opportunities and challenges that still need to be overcome before these ALP sensing technologies can be used in clinical and field settings.</div></div>","PeriodicalId":302,"journal":{"name":"Dyes and Pigments","volume":"249 ","pages":"Article 113586"},"PeriodicalIF":4.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146036582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Peanut-derived carbon dots as a fluorescence probe for the determination of fluazinam and temperature","authors":"Shen Zhang,&nbsp;Zhuo Wang","doi":"10.1016/j.dyepig.2026.113630","DOIUrl":"10.1016/j.dyepig.2026.113630","url":null,"abstract":"<div><div>In consideration of the potential threat, the establishment of efficient approach for fluazinam determination is necessary. Based on the superior property of carbon dots and biomass, sulfur doped biomass-based carbon dots (SBCDs) were constructed using a simple hydrothermal approach, in which peanuts were applied as carbon sources with the addition of methionine. The well-dispersed SBCDs displayed optimal emission wavelength of 435 nm under the excitation wavelength of 364 nm. Owing to the detection principle of fluorescence quenching through static quenching and inner filter effects, the SBCDs were used to detect fluazinam with a broad linear range of 0-100 μM and a detection limit of 0.026 μM. Additionally, the SBCDs also exhibited temperature sensing with a wide linear range of 15-95 °C. Moreover, the as-prepared SBCDs were effectively used for the determination of fluazinam in tap water and orange juice samples. The SBCDs displayed tremendous potential for the sensing of fluazinam and temperature.</div></div>","PeriodicalId":302,"journal":{"name":"Dyes and Pigments","volume":"249 ","pages":"Article 113630"},"PeriodicalIF":4.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146184782","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cholesteric copolymerization strategy endows achiral fluorophore with bright circularly polarized luminescence","authors":"Leshi Li ,&nbsp;Haowen Deng ,&nbsp;Zixuan Zhang,&nbsp;Zhuping Chen,&nbsp;Jingjing He,&nbsp;Qiannan Wang,&nbsp;Zepeng Wang,&nbsp;Zhen-Qiang Yu,&nbsp;Yue Wu","doi":"10.1016/j.dyepig.2026.113611","DOIUrl":"10.1016/j.dyepig.2026.113611","url":null,"abstract":"<div><div>Materials that can emit circularly polarized luminescence (CPL) are attracting considerable interest because of their unique chiroptical properties and broad range of applications. Most reported CPL-active materials, however, have low luminescence dissymmetry factors (|<em>g</em>_lᵤ_m|), limited quantum efficiency as well as poor stability and processability. Here, a copolymerization strategy, involving an achiral luminescent dye (a tetraphenylethylene (TPE) derivative) as the emitter and chiral cholesterol (Chol) moieties to induce helicity, was proposed to prepare polymer, poly-TPE-Chol. Thin film of poly-TPE-Chol shows highly dissymmetric and emissive CPL with a high |<em>g</em>_lᵤ_m| of 1.11 × 10⁻² and a photoluminescence quantum yield (QY) of 28.6%, beyond those of TPE-Chol monomer. This is attributed to promoted chiral supramolecular ordering and increased molecular confinement for suppressing non-radiative decay towards TPE units in poly-TPE-Chol, respectively. This strategy, proven to be general, paves the way for designing non-doped CPL polymers with high |<em>g</em>_lum| values and QY.</div></div>","PeriodicalId":302,"journal":{"name":"Dyes and Pigments","volume":"249 ","pages":"Article 113611"},"PeriodicalIF":4.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146184780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"When true colors still shine through: LC-MS-based metabolomics study of fabrics dyed with European buckthorn (Rhamnus cathartica) berries after accelerated light ageing","authors":"Marine Chambaud ,&nbsp;Lindsay Mas-Normand ,&nbsp;Céline Joliot ,&nbsp;Carole Mathe ,&nbsp;Olivier Dangles ,&nbsp;Gérald Culioli","doi":"10.1016/j.dyepig.2026.113625","DOIUrl":"10.1016/j.dyepig.2026.113625","url":null,"abstract":"<div><div>Since prehistoric times, humans have used dye-producing plants to color textiles, artworks, and ritual objects. Yellow-yielding species have been especially important due to their availability and the chemical stability of many of their flavonoid-based colorants. Among them, <em>Rhamnus</em> species (buckthorns) are notable for producing yellow to greenish hues from their flavonoid-rich berries. These long-standing practices inform modern research on natural colorants, phytochemistry, and sustainable textile science.</div><div>In this context, this study investigates the chemical and chromatic evolution of cotton fabrics dyed with <em>Rhamnus cathartica</em> (European buckthorn) berries when subjected to accelerated light ageing. Fabrics were exposed to xenon-lamp irradiation equivalent to 3, 30, and 300 years of museum-type light. Color fading was assessed by CIELAB colorimetry, and dye degradation was analyzed using LC-DAD and untargeted LC-MS-based metabolomics. Colorimetric data showed rapid fading, fabrics appearing even whiter than undyed samples after the 300-year equivalent exposure. LC-DAD analysis revealed a drastic decline of most coloring compounds, including flavonoids and anthraquinones, which became undetectable in the most aged samples, highlighting the limited sensitivity of LC-DAD for heavily degraded textiles. In contrast, LC-MS metabolomics enabled the detection and putative annotation of 25 dye molecules, mainly flavonoid glycosides and anthraquinones. Molecular networking highlighted distinct structural families, and surprisingly many dye-related compounds remained detectable even in fully bleached fabrics.</div><div>These results demonstrated that LC-MS-based metabolomics can constitute a powerful tool for identifying residual dyes in historical textiles, supporting conservation and reconstruction of ancient dyeing practices.</div></div>","PeriodicalId":302,"journal":{"name":"Dyes and Pigments","volume":"249 ","pages":"Article 113625"},"PeriodicalIF":4.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146184784","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A fluorinated quinoidal A-DA′D-A small molecule enables high-performance NIR-II photoacoustic imaging","authors":"Zengrong Li ,&nbsp;Xuelong Huang ,&nbsp;Xiaoyan Li ,&nbsp;Zihong Chen ,&nbsp;Chu Liu ,&nbsp;Xinru Chen ,&nbsp;Yongjun Deng ,&nbsp;Yuchen Pan ,&nbsp;Tao Jia ,&nbsp;Zhixiong Cao","doi":"10.1016/j.dyepig.2026.113632","DOIUrl":"10.1016/j.dyepig.2026.113632","url":null,"abstract":"<div><div>Most organic small-molecule photoacoustic (PA) contrast agents exhibit absorption in the NIR-I window (700–900 nm), limiting their utility in deep-tissue imaging due to insufficient signal-to-noise ratio (SNR) and penetration depth. To address this, we repurpose the A-DA′D-A-type molecule Y-QC4F—featuring difluorinated quinoidal acceptors—for NIR-II (1000–1700 nm) PA imaging. The synergistic integration of quinoidal character and fluorination narrows the optical bandgap and extends π-conjugation, redshifting the thin-film absorption maximum to 1052 nm—closely aligned with the commonly used 1064 nm laser excitation wavelength. Upon nanoformulation with DSPE-mPEG₂₀₀₀, Y-QC4F@NPs display strong NIR-II absorption in aqueous media, a high photothermal conversion efficiency (49.9%), and robust photostability. <em>In vivo</em>, intravenous administration yields a 51.4-fold PA signal enhancement in mouse ear vasculature (resolving vessels down to 40 μm) and a 173.2-fold enhancement in cerebral vasculature (60 μm resolution), demonstrating clear blood–brain barrier penetration. Combined with minimal cytotoxicity, negligible hemolysis, and no observable histological damage, this work establishes the synergy between quinoidal architecture and strategic fluorination as a rational molecular design strategy for high-performance A-DA′D-A-type small-molecule NIR-II photoacoustic contrast agents.</div></div>","PeriodicalId":302,"journal":{"name":"Dyes and Pigments","volume":"249 ","pages":"Article 113632"},"PeriodicalIF":4.2,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146184786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}