Organic Semiconducting Agents for Deep‐Tissue Molecular Imaging: Second Near‐Infrared Fluorescence, Self‐Luminescence, and Photoacoustics

Advanced Materials, Journal Year: 2018, Volume and Issue: 30(49)

Published: July 29, 2018

Optical imaging has played a pivotal role in biology and medicine, but it faces challenges of relatively low tissue penetration poor signal-to-background ratio due to light scattering autofluorescence. To overcome these issues, second near-infrared fluorescence, self-luminescence, photoacoustic have recently emerged, which utilize an optical region with reduced light-tissue interactions, eliminate real-time excitation, detect acoustic signals negligible attenuation, respectively. Because there are only few endogenous molecules absorbing or emitting above the visible region, development contrast agents is essential for those deep-tissue modalities. Organic semiconducting π-conjugated frameworks can be synthesized meet different requirements their easy chemical modification legible structure-property relation. Herein, applications organic including small-molecule nanoparticle derivatives summarized. In particular, molecular engineering nanoformulation approaches further improve detection sensitivity modalities highlighted. Finally, current potential opportunities this emerging subfield biomedical discussed.

Language: Английский

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Recent advances in near-infrared II fluorophores for multifunctional biomedical imaging

Chemical Science, Journal Year: 2018, Volume and Issue: 9(19), P. 4370 - 4380

Published: Jan. 1, 2018

In recent years, owing to unsatisfactory clinical imaging clarity and depths in the living body for early diagnosis prognosis, novel modalities with high bioimaging performance have been actively explored. The remarkable headway made second near-infrared region (NIR-II, 1000-1700 nm) has promoted development of biomedical significantly. NIR-II fluorescence possesses a number merits which prevail over traditional NIR-I (400-900 fundamental research, such as reduced photon scattering, well auto-fluorescence improved penetration depth. Functional probes instant precise feedback vivo information are at core this modality superb imaging. Herein, we review recently developed fluorophores including carbon nanotubes, organic small molecules, quantum dots, conjugated polymers rare-earth-doped materials present superior multifunctionality regions (1000-1700 nm).

Language: Английский

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Donor Engineering for NIR-II Molecular Fluorophores with Enhanced Fluorescent Performance

Journal of the American Chemical Society, Journal Year: 2018, Volume and Issue: 140(5), P. 1715 - 1724

Published: Jan. 16, 2018

Organic fluorophores have been widely used for biological imaging in the visible and first near-infrared windows. However, their application second window (NIR-II, 1000–1700 nm) is still limited mainly due to low fluorescence quantum yields (QYs). Here, we explore molecular engineering on donor unit develop high performance NIR-II fluorophores. The are constructed by a shielding unit–donor(s)–acceptor–donor(s)–shielding structure. Thiophene introduced as connected unit, which can increase conjugation length red-shift emission. Alkyl thiophene employed acceptor unit. bulky hydrophobic alkyl affords larger distortion of conjugated backbone fewer interactions with water molecules compared other units studied before. fluorophore IR-FTAP octyl exhibits emission peaked at 1048 nm QY 5.3% aqueous solutions, one highest reported so far. Superior temporal spatial resolutions demonstrated blood vessels mouse hindlimb.

Language: Английский

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Multimodal Biophotonics of Semiconducting Polymer Nanoparticles

Accounts of Chemical Research, Journal Year: 2018, Volume and Issue: 51(8), P. 1840 - 1849

Published: Aug. 3, 2018

ConspectusBiophotonics as an interdisciplinary frontier plays increasingly important role in modern biomedical science. Optical agents are generally involved biophotonics to interpret biomolecular events into readable optical signals for imaging and diagnosis or convert photons other forms of energy (such heat, mechanical force, chemical radicals) therapeutic intervention biological stimulation. Development new including metallic nanoparticles, quantum dots, up-conversion carbon silica nanoparticles has contributed the advancement this field. However, most these have their own merits demerits, making them less effective multimodal biophotonic platforms.In Account, we summarize our recent work on development near-infrared (NIR) semiconducting polymer (SPNs) light converters advanced biophotonics. SPNs composed π-electron delocalized polymers (SPs) often possess advantages good biocompatibility, high photostability, large absorption coefficients. Because photophysical properties mainly determined by molecular structures precursor polymers, engineering allows us fine tune processes obtain different responses, even second NIR window (1000–1700 nm). Meanwhile, facile nanoformulation methods enable alteration outer inner diverse interactions.The unique brought about ultrasensitive deep-tissue imaging. NIR-absorbing with strong charge-transfer backbones can photoenergy acoustic waves, permitting photoacoustic that bypasses issue scattering reaches centimeter tissue penetration depth. Differently, phenylenevinylene-containing store photon via defects emit long-NIR afterglow luminescence a half-life ∼6 min after cessation excitation. Such process avoids autofluorescence, giving rise ultrahigh signal-to-background ratios. So far, SPN-based probes been developed image disease tissues (tumors), biomarkers (biothiols reactive oxygen species), physiological indexes (pH temperature) preclinical animal models.The synthetic flexibility further permits light-modulated interventions. Till now, photothermal conversion efficiencies shaped transducers remotely regulate protein ion channels, enzymatic activity, gene expression. In conjunction desired biodistribution tumor-homing ability, doped coated inorganic amplified self-regulated photodynamic cancer therapy.This Account thus demonstrates serve nanoplatform provide unprecedented opportunities imaging, noninvasive bioactivation, therapy.

Language: Английский

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Recent Advances in Cell Membrane–Camouflaged Nanoparticles for Cancer Phototherapy

Small, Journal Year: 2018, Volume and Issue: 15(1)

Published: Nov. 20, 2018

Abstract Phototherapy including photothermal therapy (PTT) and photodynamic (PDT) employs phototherapeutic agents to generate heat or cytotoxic reactive oxygen species (ROS), has therefore garnered particular interest for cancer therapy. However, the main challenges faced by conventional include easy recognition immune system, rapid clearance from blood circulation, low accumulation in target sites. Cell‐membrane coating emerged as a potential way overcome these limitations, owing abundant proteins on surface of cell membranes that can be inherited membrane–camouflaged nanoparticles. This review summarizes recent advances development biomimetic nanoparticles phototherapy. Different sources used coat uisng different approaches. After cell‐membrane coating, photophysical properties original remain nearly unchanged; however, coated are equipped with additional physiological features escape, vivo prolonged circulation time, homologous targeting, depending sources. Moreover, membrane ablated under laser irradiation, leading drug release thus synergetic By combining other supplementary normalize tumor microenvironment, further enhance therapeutic efficacy against cancer.

Language: Английский

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Recent progress on semiconducting polymer nanoparticles for molecular imaging and cancer phototherapy

Biomaterials, Journal Year: 2017, Volume and Issue: 155, P. 217 - 235

Published: Nov. 22, 2017

Language: Английский

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Miniature gold nanorods for photoacoustic molecular imaging in the second near-infrared optical window

Nature Nanotechnology, Journal Year: 2019, Volume and Issue: 14(5), P. 465 - 472

Published: March 4, 2019

Language: Английский

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Reducing aggregation caused quenching effect through co-assembly of PAH chromophores and molecular barriers

Nature Communications, Journal Year: 2019, Volume and Issue: 10(1)

Published: Jan. 8, 2019

Abstract The features of well-conjugated and planar aromatic structures make π-conjugated luminescent materials suffer from aggregation caused quenching (ACQ) effect when used in solid or aggregated states, which greatly impedes their applications optoelectronic devices biological applications. Herein, we reduce the ACQ by demonstrating a facile low cost method to co-assemble polycyclic hydrocarbon (PAH) chromophores octafluoronaphthalene together. Significantly, photoluminescence quantum yield (PLQYs) for as-resulted four micro/nanococrystals are enhanced 254%, 235%, 474 582%, respectively. Protection hydrophilic polymer chains (P123 (PEO 20 -PPO 70 -PEO )) endows cocrystals with superb dispersibility water. More importantly, profiting above-mentioned highly improved properties, nano-cocrystals present good biocompatibility considerable cell imaging performance. This research provides simple enhance emission, cellular permeability common chromophores, may open more avenues originally non- poor fluorescent PAHs.

Language: Английский

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Transformable hybrid semiconducting polymer nanozyme for second near-infrared photothermal ferrotherapy

Nature Communications, Journal Year: 2020, Volume and Issue: 11(1)

Published: April 20, 2020

Despite its growing promise in cancer treatment, ferrotherapy has low therapeutic efficacy due to compromised Fenton catalytic efficiency tumor milieu. We herein report a hybrid semiconducting nanozyme (HSN) with high photothermal conversion for photoacoustic (PA) imaging-guided second near-infrared ferrotherapy. HSN comprises an amphiphilic polymer as converter, PA emitter and iron-chelating catalyst. Upon photoirradiation, generates heat not only induce cytotoxicity but also enhance reaction. The increased ·OH generation promotes both ferroptosis apoptosis, oxidizes (42 nm) transforms it into tiny segments (1.7 elevated intratumoral permeability. non-invasive seamless synergism leads amplified effects including deep ablation depth (9 mm), reduced expression of metastasis-related proteins inhibition metastasis from primary distant organs. Thereby, our study provides generalized strategy compensate phototherapeutics complete regression.

Language: Английский

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Semiconducting Polymer Nanomaterials as Near-Infrared Photoactivatable Protherapeutics for Cancer

Accounts of Chemical Research, Journal Year: 2020, Volume and Issue: 53(4), P. 752 - 762

Published: Feb. 6, 2020

Cancer therapy is routinely performed in the clinic to cure cancer and control its progression, wherein therapeutic agents are generally used. To reduce side effects, protherapeutic that can be activated by overexpressed biomarkers under development. However, these still face certain extent of off-target activation normal tissues, stimulating interest design external-stimuli activatable protherapeutics. In this regard, photoactivatable have been utilized for treatments. because intrinsic features photolabile moieties, most only respond ultraviolet-visible light, limiting their vivo applications. Thus, near-infrared (NIR) light with minimal phototoxicity increased tissue penetration highly desired.In Account, we summarize our semiconducting polymer nanomaterials (SPNs) as NIR treatment. SPNs transformed from π-conjugated polymers efficiently convert into heat or singlet oxygen (1O2). With photothermal photodynamic properties, directly used photomedicine serve transducers activate 1O2-responsive agents.The heat-activatable SPN-based developed loading conjugating (e.g., agonist, gene, enzyme). For instance, photothermally triggered release agonists specifically activates protein ion channels on cellular membrane, leading overinflux induced mitochondria dysfunction consequently apoptosis cells. Moreover, temperature-sensitive bromelain promote situ degradation collagens (the major components extracellular matrix), resulting an improved accumulation tumor tissues thus amplified outcome.The 1O2-activatable constructed through covalent conjugation caged via hypoxia- 1O2-cleavable linkers. Upon photoirradiation, consume generate 1O2, which leads (PDT), meanwhile breaks linkers on-demand molecules chemodrug, enzyme, inhibitor). Such remote applied induce DNA damage, ribonucleic acid degradation, inhibition biosynthesis, immune system tumors living animals. By synergizing PDT photoactivation those biological actions, effectively eliminate even fully inhibit metastasis.This Account highlights potential construction versatile protherapeutics treat at designated times locations high outcome precision.

Language: Английский

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