scholarly journals Towards new NIR dyes for free radical photopolymerization processes

2021 ◽  
Vol 17 ◽  
pp. 2067-2076
Author(s):  
Haifaa Mokbel ◽  
Guillaume Noirbent ◽  
Didier Gigmes ◽  
Frédéric Dumur ◽  
Jacques Lalevée
Keyword(s):  
Near Infrared ◽  
Polymer Networks ◽  
Interpenetrating Polymer Networks ◽  
Nir Dyes ◽  
Nir Light ◽  
Free Radical Photopolymerization ◽  
Epoxy Monomer ◽  
Iodonium Salt ◽  
Nir Dye ◽  
Positively Charged

The use of cheap and safe near-infrared (NIR) light is still the subject of intense research efforts but remains a huge challenge due to the associated low photon energy (wavelength from 0.78 to 2.5 µm). In this study, a series of 17 NIR dyes mainly based on a well-established cyanine scaffold is proposed. Remarkably, 11 of them were never synthesized before. Markedly, noncharged structures, negatively charged cyanine bearing Na+ as counter cation, and positively charged cyanines bearing (B(Ph)4−) or (I−) as counter anions were examined as promising NIR light photoinitiating systems. Excellent photoinitiating abilities were found for some reported dyes when used in combination with iodonium salt and amine. Markedly, photothermal effects with a huge heater behavior were also observed for different NIR dye structures. Interestingly, the synthesis of interpenetrating polymer networks (IPNs, e.g., for the polymerization of acrylate/epoxy monomer blends) can also be carried out upon NIR light with the proposed systems.

scholarly journals Detection of early neoplasia in Barrett’s esophagus using lectin-based near-infrared imaging: an ex vivo study on human tissue

Endoscopy ◽  
2018 ◽  
Vol 50 (06) ◽  
pp. 618-625 ◽  
Author(s):  
André Neves ◽  
Massimiliano Di Pietro ◽  
Maria O’Donovan ◽  
Dale Waterhouse ◽  
Sarah Bohndiek ◽  
...  
Keyword(s):  
Barrett’S Esophagus ◽  
Barrett's Esophagus ◽  
Near Infrared ◽  
Infrared Imaging ◽  
Ex Vivo ◽  
Sampling Error ◽  
Nir Light ◽  
Nir Imaging ◽  
Nir Fluorescence ◽  
Nir Dye

Abstract Background and study aims Endoscopic surveillance for Barrett’s esophagus (BE) is limited by long procedure times and sampling error. Near-infrared (NIR) fluorescence imaging minimizes tissue autofluorescence and optical scattering. We assessed the feasibility of a topically applied NIR dye-labeled lectin for the detection of early neoplasia in BE in an ex vivo setting. Methods Consecutive patients undergoing endoscopic mucosal resection (EMR) for BE-related early neoplasia were recruited. Freshly collected EMR specimens were sprayed at the bedside with fluorescent lectin and then imaged. Punch biopsies were collected from each EMR under NIR light guidance. We compared the fluorescence intensity from dysplastic and nondysplastic areas within EMRs and from punch biopsies with different histological grades. Results 29 EMR specimens were included from 17 patients. A significantly lower fluorescence was found for dysplastic regions across whole EMR specimens (P < 0.001). We found a 41 % reduction in the fluorescence of dysplastic compared to nondysplastic punch biopsies (P < 0.001), with a sensitivity and specificity for dysplasia detection of 80 % and 82.9 %, respectively. Conclusion Lectin-based NIR imaging can differentiate dysplastic from nondysplastic Barrett’s mucosa ex vivo.

Thermo- and photo-stable symmetrical benzo[cd]indolenyl-substituted heptamethine cyanine dye carrying a tetrakis(pentafluorophenyl)borate that absorbs only near-infrared light over 1000 nm

2019 ◽  
Vol 43 (19) ◽  
pp. 7491-7501
Author(s):  
Kazumasa Funabiki ◽  
Ryuta Yanagawa ◽  
Yasuhiro Kubota ◽  
Toshiyasu Inuzuka
Keyword(s):  
Near Infrared ◽  
Cyanine Dye ◽  
Infrared Light ◽  
Near Infrared Light ◽  
Nir Dyes ◽  
Nir Light

Thermo- and photo-stable NIR dyes absorbing only NIR light of over 1000 nm have been investigated.

scholarly journals Lawsone Derivatives as Efficient Photopolymerizable Initiators for Free-Radical, Cationic Photopolymerizations, and Thiol—Ene Reactions

Polymers ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2015
Author(s):  
Christine Elian ◽  
Vlasta Brezová ◽  
Pauline Sautrot-Ba ◽  
Martin Breza ◽  
Davy-Louis Versace
Keyword(s):  
Free Radical ◽  
Paramagnetic Resonance ◽  
Ene Reactions ◽  
Ene Reaction ◽  
Free Radical Photopolymerization ◽  
Abstraction Reaction ◽  
Epoxy Monomer ◽  
Iodonium Salt ◽  
Epr Spin Trapping ◽  
Electron Paramagnetic

Two new photopolymerizable vinyl (2-(allyloxy) 1,4-naphthoquinone, HNQA) and epoxy (2-(oxiran-2yl methoxy) 1,4-naphthoquinone, HNQE) photoinitiators derived from lawsone were designed in this paper. These new photoinitiators can be used as one-component photoinitiating systems for the free-radical photopolymerization of acrylate bio-based monomer without the addition of any co-initiators. As highlighted by the electron paramagnetic resonance (EPR) spin-trapping results, the formation of carbon-centered radicals from an intermolecular H abstraction reaction was evidenced and can act as initiating species. Interestingly, the introduction of iodonium salt (Iod) used as a co-initiator has led to (1) the cationic photopolymerization of epoxy monomer with high final conversions and (2) an increase of the rates of free-radical polymerization of the acrylate bio-based monomer; we also demonstrated the concomitant thiol–ene reaction and cationic photopolymerizations of a limonene 1,2 epoxide/thiol blend mixture with the HNQA/Iod photoinitiating system.

Near-Infrared and Rheological Investigations of Epoxy−Vinyl Ester Interpenetrating Polymer Networks

2001 ◽  
Vol 34 (19) ◽  
pp. 6623-6630 ◽  
Author(s):  
Katherine Dean ◽  
Wayne D. Cook ◽  
Laurent Rey ◽  
Jocelyne Galy ◽  
Henry Sautereau
Keyword(s):  
Vinyl Ester ◽  
Near Infrared ◽  
Polymer Networks ◽  
Interpenetrating Polymer Networks

Catalyst Halogenation Enables Rapid and Efficient Polymerizations with Visible to Near-Infrared Light

2020 ◽  
Author(s):  
Alex Stafford ◽  
Dowon Ahn ◽  
Emily Raulerson ◽  
Kun-You Chung ◽  
Kaihong Sun ◽  
...  
Keyword(s):  
Near Infrared ◽  
Transient Absorption ◽  
Reaction Times ◽  
Infrared Light ◽  
Structure Property ◽  
Light Emitting ◽  
Structure Property Relationships ◽  
Nir Light ◽  
Light Intensities ◽  
Emission Quenching

Driving rapid polymerizations with visible to near-infrared (NIR) light will enable nascent technologies in the emerging fields of bio- and composite-printing. However, current photopolymerization strategies are limited by long reaction times, high light intensities, and/or large catalyst loadings. Improving efficiency remains elusive without a comprehensive, mechanistic evaluation of photocatalysis to better understand how composition relates to polymerization metrics. With this objective in mind, a series of methine- and aza-bridged boron dipyrromethene (BODIPY) derivatives were synthesized and systematically characterized to elucidate key structure-property relationships that facilitate efficient photopolymerization driven by visible to NIR light. For both BODIPY scaffolds, halogenation was shown as a general method to increase polymerization rate, quantitatively characterized using a custom real-time infrared spectroscopy setup. Furthermore, a combination of steady-state emission quenching experiments, electronic structure calculations, and ultrafast transient absorption revealed that efficient intersystem crossing to the lowest excited triplet state upon halogenation was a key mechanistic step to achieving rapid photopolymerization reactions. Unprecedented polymerization rates were achieved with extremely low light intensities (< 1 mW/cm<sup>2</sup>) and catalyst loadings (< 50 μM), exemplified by reaction completion within 60 seconds of irradiation using green, red, and NIR light-emitting diodes.

The Role of NIR Fluorescence in MDR Cancer Treatment: From Targeted Imaging to Phototherapy

2020 ◽  
Vol 27 (33) ◽  
pp. 5510-5529
Author(s):  
Zengtao Wang ◽  
Qingqing Meng ◽  
Shaoshun Li
Keyword(s):  
Cancer Treatment ◽  
Near Infrared ◽  
Combined Therapy ◽  
Efflux Pumps ◽  
Cross Resistance ◽  
Great Promise ◽  
Drug Efflux ◽  
Nir Dyes ◽  
Nir Imaging ◽  
Drug Efflux Pumps

Background: Multidrug Resistance (MDR) is defined as a cross-resistance of cancer cells to various chemotherapeutics and has been demonstrated to correlate with drug efflux pumps. Visualization of drug efflux pumps is useful to pre-select patients who may be insensitive to chemotherapy, thus preventing patients from unnecessary treatment. Near-Infrared (NIR) imaging is an attractive approach to monitoring MDR due to its low tissue autofluorescence and deep tissue penetration. Molecular NIR imaging of MDR cancers requires stable probes targeting biomarkers with high specificity and affinity. Objective: This article aims to provide a concise review of novel NIR probes and their applications in MDR cancer treatment. Results: Recently, extensive research has been performed to develop novel NIR probes and several strategies display great promise. These strategies include chemical conjugation between NIR dyes and ligands targeting MDR-associated biomarkers, native NIR dyes with inherent targeting ability, activatable NIR probes as well as NIR dyes loaded nanoparticles. Moreover, NIR probes have been widely employed for photothermal and photodynamic therapy in cancer treatment, which combine with other modalities to overcome MDR. With the rapid advancing of nanotechnology, various nanoparticles are incorporated with NIR dyes to provide multifunctional platforms for controlled drug delivery and combined therapy to combat MDR. The construction of these probes for MDR cancers targeted NIR imaging and phototherapy will be discussed. Multimodal nanoscale platform which integrates MDR monitoring and combined therapy will also be encompassed. Conclusion: We believe these NIR probes project a promising approach for diagnosis and therapy of MDR cancers, thus holding great potential to reach clinical settings in cancer treatment.

Bi19S27I3 nanorods: a new candidate for photothermal therapy in the first and second biological near-infrared windows

Nanoscale ◽  
2021 ◽  
Author(s):  
Jinsong Xiong ◽  
Qinghuan Bian ◽  
Shuijin Lei ◽  
Yatian Deng ◽  
Kehan Zhao ◽  
...  
Keyword(s):  
Cancer Therapy ◽  
Photothermal Therapy ◽  
Near Infrared ◽  
Research Interest ◽  
The Past ◽  
Nir Light ◽  
Considerable Research ◽  
Key Factor

Near-infrared (NIR) light induced photothermal cancer therapy using nanomaterials as photothermal agents has attracted considerable research interest over the past few years. As the key factor in the photothermal therapy...

scholarly journals The microscopic distribution of hydrophilic polymers in interpenetrating polymer networks (IPNs) of medical grade silicone

Polymer ◽  
2021 ◽  
Vol 224 ◽  
pp. 123671
Author(s):  
Gregory N. Smith ◽  
Erik Brok ◽  
Martin Schmiele ◽  
Kell Mortensen ◽  
Wim G. Bouwman ◽  
...  
Keyword(s):  
Polymer Networks ◽  
Interpenetrating Polymer Networks ◽  
Hydrophilic Polymers ◽  
Microscopic Distribution ◽  
Medical Grade

Organic-solvent-free electromembrane extraction based on semi-interpenetrating polymer networks

2021 ◽  
Author(s):  
Hang Mei ◽  
Huajing Liu ◽  
Qianqian Shang ◽  
Ying Dong ◽  
Stig Pedersen-Bjergaard ◽  
...  
Keyword(s):  
Organic Solvent ◽  
Polymer Networks ◽  
Interpenetrating Polymer Networks ◽  
Solvent Free ◽  
Electromembrane Extraction ◽  
Acidic Analytes

A versatile organic-solvent-free electromembrane extraction (EME) system, which could be successfully used for the extraction of both basic and acidic analytes, is proposed based on semi-interpenetrating polymer networks.

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