Facial Control Intramolecular Charge Transfer of Quinoid Conjugated Polymers for Efficient in Vivo NIR-II Imaging

2019 ◽  
Vol 11 (18) ◽  
pp. 16311-16319 ◽  
Author(s):  
Wansu Zhang ◽  
Ting Huang ◽  
Jiewei Li ◽  
Pengfei Sun ◽  
Yufeng Wang ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Conjugated Polymers ◽  
Intramolecular Charge Transfer

scholarly journals Red Room-Temperature Phosphorescent Diimides: Molecular Design and Application

2019 ◽  
Author(s):  
Jiajun Du ◽  
Fan Liao ◽  
Ziye Wu ◽  
Wenhuan Huang ◽  
Fei Li ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Room Temperature ◽  
Molecular Design ◽  
Intramolecular Charge Transfer ◽  
Imaging Studies ◽  
Oxygen Sensitive ◽  
Photo Induced Electron Transfer ◽  
Naphthalene Diimides ◽  
Transfer State

N-Substituted naphthalene diimides (NDIs) were explored as purely organic room temperature phosphorescence (RTP) materials based on the strategy of intramolecular charge-transfer (ICT) mediation. A series of NDIs were designed and investigated for their luminescence properties. All emissive NDIs exhibited similar red RTP (emission range from ~600 to ~800 nm) in solid state media; the quantum yield (QY) of the obtained RTP relies heavily on the N-substitution. From poor to moderate to strong donor moieties, the QY increases but suddenly disappears. First-principle calculations reveal that a “sweet spot” for strong NDI RTP exists: while a suitable charge-transfer state can enhance RTP, a strong donor may cause total triplet quenching through the photo-induced electron transfer (PET) mechanism. Furthermore, combining NDI aggregation effects, we realized the reddest RTP ever reported for purely organic materials (Max emission = 675 nm, QY = 21.7%). Given the red emission, respectable QY and oxygen sensitive properties for some of the NDIs, they were tested as imaging agents for in vivo imaging studies.

scholarly journals Red Room-Temperature Phosphorescent Diimides: Molecular Design and Application

2019 ◽  
Author(s):  
Jiajun Du ◽  
Fan Liao ◽  
Ziye Wu ◽  
Wenhuan Huang ◽  
Fei Li ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Room Temperature ◽  
Molecular Design ◽  
Intramolecular Charge Transfer ◽  
Imaging Studies ◽  
Oxygen Sensitive ◽  
Photo Induced Electron Transfer ◽  
Naphthalene Diimides ◽  
Transfer State

N-Substituted naphthalene diimides (NDIs) were explored as purely organic room temperature phosphorescence (RTP) materials based on the strategy of intramolecular charge-transfer (ICT) mediation. A series of NDIs were designed and investigated for their luminescence properties. All emissive NDIs exhibited similar red RTP (emission range from ~600 to ~800 nm) in solid state media; the quantum yield (QY) of the obtained RTP relies heavily on the N-substitution. From poor to moderate to strong donor moieties, the QY increases but suddenly disappears. First-principle calculations reveal that a “sweet spot” for strong NDI RTP exists: while a suitable charge-transfer state can enhance RTP, a strong donor may cause total triplet quenching through the photo-induced electron transfer (PET) mechanism. Furthermore, combining NDI aggregation effects, we realized the reddest RTP ever reported for purely organic materials (Max emission = 675 nm, QY = 21.7%). Given the red emission, respectable QY and oxygen sensitive properties for some of the NDIs, they were tested as imaging agents for in vivo imaging studies.

A Fluorescent Probe for Hydrogen Peroxide in Vivo Based on the Modulation of Intramolecular Charge Transfer

2017 ◽  
Vol 89 (10) ◽  
pp. 5278-5284 ◽  
Author(s):  
Yuzhi Chen ◽  
Xiaomin Shi ◽  
Zhengliang Lu ◽  
Xuefei Wang ◽  
Zhuo Wang
Keyword(s):  
Hydrogen Peroxide ◽  
Charge Transfer ◽  
Fluorescent Probe ◽  
Intramolecular Charge Transfer

Novel low-band-gap conjugated polymers using an alternating donor/acceptor repeat unit

e-Polymers ◽  
2010 ◽  
Vol 10 (1) ◽  
Author(s):  
Phimwipha Piyakulawat ◽  
Anusit Keawprajak ◽  
Anon Chindaduang ◽  
Anke Helfer ◽  
Udom Asawapirom
Keyword(s):  
Cyclic Voltammetry ◽  
Charge Transfer ◽  
Conjugated Polymers ◽  
Lower Energy ◽  
Intramolecular Charge Transfer ◽  
Repeat Unit ◽  
Band Gaps ◽  
Donor And Acceptor ◽  
Donor Acceptor ◽  
Positive Step

AbstractA series of new π-conjugated donor-acceptor copolymers, based on a naphthalene-bisimide moiety as the electron-acceptor and connected to either thiophene or dialkylfluorene as the electron-donor, were synthesized. The polymers are soluble in common organic solvents. The UV-Vis spectra of the copolymers in chloroform showed two absorption maxima at higher energies (ca. 301 - 364 nm), assigned to the π-π * transition, and at a lower energy (ca. 512 - 595 nm), ascribed to the intramolecular charge transfer between donor and acceptor units. Cyclic voltammetry revealed that the polymers were susceptible to both electrochemical oxidation and reduction, and they had a LUMO and HOMO levels ranging from -4.07 to -3.80 eV and -6.13 to -5.64 eV, respectively. The energy band gaps were estimated to be 1.48 - 2.06 eV. These results represent a positive step towards making novel compounds suitable for electronic applications.

scholarly journals A Novel Dialkylamino GFP Chromophore as an Environment-Polarity Sensor Reveals the Role of Twisted Intramolecular Charge Transfer

Chemosensors ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 234
Author(s):  
Cheng Chen ◽  
Sean A. Boulanger ◽  
Anatolii I. Sokolov ◽  
Mikhail S. Baranov ◽  
Chong Fang
Keyword(s):  
Charge Transfer ◽  
Transient Absorption ◽  
Fluorescent Protein ◽  
Intramolecular Charge Transfer ◽  
Multivariable Analysis ◽  
Solvent Polarity ◽  
Dimethylamino Group ◽  
Twisted Intramolecular Charge Transfer

We discovered a novel fluorophore by incorporating a dimethylamino group (–NMe2) into the conformationally locked green fluorescent protein (GFP) scaffold. It exhibited a marked solvent-polarity-dependent fluorogenic behavior and can potentially find broad applications as an environment-polarity sensor in vitro and in vivo. The ultrafast femtosecond transient absorption (fs-TA) spectroscopy in combination with quantum calculations revealed the presence of a twisted intramolecular charge transfer (TICT) state, which is formed by rotation of the –NMe2 group in the electronic excited state. In contrast to the bright fluorescent state (FS), the TICT state is dark and effectively quenches fluorescence upon formation. We employed a newly developed multivariable analysis approach to the FS lifetime in various solvents and showed that the FS → TICT reaction barrier is mainly modulated by H-bonding capability instead of viscosity of the solvent, accounting for the observed polarity dependence. These deep mechanistic insights are further corroborated by the dramatic loss of fluorogenicity for two similar GFP-derived chromophores in which the rotation of the –NMe2 group is inhibited by structural locking.

Sign in / Sign up

Export Citation Format

Share Document