A simple“spraying”fluorescence-guided surgery by AIE probes for liver tumor resection through configuration-induced cross-identification

Surgical resection is the preferred option for hepatocellular carcinoma(HCC),but surgical navigation technology using indocyanine green still has some drawbacks such as non-specific imaging,thus it is very important to develop newfluorescence imaging technology.All-cis hexaphenyl-1,3-butadiene derivative(ZZ-HPB-NC)with aggregation-induced emission(AIE)feature has been reported to be quickly turned-onfluorescent response in the intraoperative frozen-section slides of HCC.However,the probe did not respond to normal liver tissue around HCC.In order to enhance the diagnostic rate and elucidate the response mechanism,all-trans config-uration EE-HPB-NC,was furtherly synthesized.Within two minutes,non-cancer tissues could befluorescently labeled by EE-HPB-NC by spraying,showing the same effect with ZZ-HPB-NC to HCC.The results indicated that the configuration-induced cross-identificationfluorescence imaging strategy was achieved through the combination of ZZ-and EE-HPB-NC.Then the mechanism of HPB-NC localization in HCC lesions was explored,and the binding of HPB-NC with specific proteins in cells resulted in the AIE effect to label HCC cells.On this basis,the accuracy of specificfluorescence imaging for HCC was further verified on the mouse hepatic neoplasm models,indicating that it has clinical application potential for surgicalfluorescence real-time navigation.

Thylakoid engineered M2 macrophage for sonodynamic effect promoted cell therapy of early atherosclerosis

Atherosclerosis is the most common cause of cardiovascular diseases that contribute to the major morbidity worldwide,but still lacking of effective treatment strategy.Here,a hybrid cell is constructed for the sonodynamic effect promoted cell therapy of early atherosclerosis by fusing M2 macrophages with thylakoid(TK)membranes.After systemic administration,the obtained TK-M2 actively accumulates in the early atherosclerotic plaques,wherein M2 macrophages relieve the cholesterol accumulation and the inflammation in the foam cells.Meanwhile,the TK membranes decorated on the M2 macrophages exhibit both type I and type II sonodynamic effects under ultrasound(US)activation,inducing the direct apoptosis of foam cells.The cooperation of M2 and TK leads to significant outcome in eliminating atherosclerotic plaques without obvious side-effects,providing a new avenue for atherosclerosis treatment.

Organic Host-Guest Materials with Bright Red Room-Temperature Phosphorescence for Persistent Bioimaging

Organic room-temperature phosphorescence(RTP)materials have attracted immense attention in bioimaging due to their long emission lifetime and large Stokes shift.RTP materials with long emission wavelength can improve the penetration depth for bioimaging.However,the design of red persistent RTP materials is still challenging.In this study,a fused-ring structure has been proposed to effectively decrease the triplet energy level,thus extending the emission wavelength of phosphorescence.In addition,the fused-ring structure exhibits a high molar extinction coefficient(ɛ)and high luminescence efficiency due to the rigid structure.A new class of crystalline hosts(iminodibenzyl,IDB)are developed to stabilize the triplet excitons that are generated from the fused-ring molecules.The maximum RTP wavelength of doping materials can reach 635 nm with a lifetime of 9.35 ms.Water-disperse nanoparticles are successfully prepared for in vivo time-resolved bioimaging,which eliminates the background fluorescence interference from biological tissues.These reveal a delicate design strategy for the construction of long-wavelength emissive RTP materials for high-resolution bioimaging.

Wide-range color-tunable afterglow emission by the modulation of triplet exciton transition processes based on buckybowl structure

Buckybowl structures as non-uniform electrostatic potential distributions of poly-cyclic aromatic materials show a unique photoelectric performance.In this work,OTC was utilized for dynamic modulation of triplet exciton transition processes.Five host molecules with different functional units were selected,thus providing dif-ferent intermolecular interactions in the host/guest systems.Therefore,the delayed emissions were regulated from 536 to 624 nm via the tuning of the triplet exciton transition processes of OTC in different hosts.Experimental data and theoretical calculations revealed that the varied triplet transition behaviors resulted from the competition between the intersystem crossing(ISC)process of OTC-monomer and the reverse intersystem crossing(RISC)process of OTC-aggregates.This work proves the superior structure of buckybowl-based luminophore for controlling triplet exciton transition processes and supplies a new perspective for persistent afterglow luminophore design.

聚集诱导发光

聚集诱导发光(AIE)是唐本忠院士于2001年提出的一个科学概念,是指一类在溶液中不发光或者发光微弱的分子聚集后发光显著增强的现象。高效固态发光的AIE材料有望从根本上解决有机发光材料面临的聚集导致发光猝灭难题,具有重大的实际应用价值。从分子内旋转受限到分子内运动受限,从聚集诱导发光到聚集体科学,AIE领域已经取得了许多原创性的成果。在本综述中,我们从AIE材料的分类、机理、概念衍生、性能、应用和挑战等方面讨论了AIE领域最近取得的显著进展。希望本综述能激发更多关于分子聚集体的研究,并推动材料、化学和生物医学等学科的进一步交叉融合和更大发展。

Electrospun Nanofibrous Materials for Wound Healing

Wound dressing materials which are capable of meeting the demands of accelerating wound closure and promoting wound healing process have being highly desired.Electrospun nanofibrous materials show great application potentials for wound healing owing to relatively large surface area,better mimicry of native extracellular matrix,adjustable waterproofness and breathability,and programmable drug delivery process.In this review article,we begin with a discussion of wound healing process and current commercial wound dressing materials.Then,we emphasize on electrospun nanofibrous materials for wound dressing,covering the efforts for controlling fiber alignment and morphology,constructing 3D scaffolds,developing waterproof-breathable membrane,governing drug delivery performance,and regulating stem cell behavior.Finally,we finish with challenges and future prospects of electrospun nanofibrous materials for wound dressings.

Donor strategy for promoting nonradiative decay to achieve an efficient photothermal therapy for treating cancer

Photothermal therapy(PTT)is emerging as an effective treatment for superficial carcinoma.A key challenge to the effectiveness of PTT is to develop photosensitizers with high photothermal conversion efficiency.Aiming to address this challenge,we develop a series of multi-arylpyrrole derivatives with different donors that contain different multi-rotor structures to explore highly efficient PTT photosensitizers.Among these multi-arylpyrrole derivatives,MAP4-FE nanoparticles with a small size of their donor groups and better-donating ability exhibit a high photothermal conversion efficiency(up to 72%)when they are encapsulated by an amphiphilic polymer.As a result,the MAP4-FE nanoparticles have shown satisfactory PTTeffects on in vivo tumor eradication under the guidance of photoacoustic signals.The findings of this study provide significant insights for the development of high-efficiency PTT photosensitizers for cancer treatment by making full use of the nonradiative decay of small size donors as rotors.

Aggregation-Induced Emission of Hexaphenyl-1,3-butadiene

A new type of AlE molecules based on hexaphenyl-1,3-butadienes was reported with respect to the synthesis and characterization. This material exhibited different maximum emission wavelength and enhanced emission intensity at different aggregate state （amorphous and crystalline state）.

Red-Emissive Organic Room-Temperature Phosphorescence Material for Time-Resolved Luminescence Bioimaging

Organic room-temperature phosphorescence(RTP)materials have been used in high-resolution imaging.However,the development of long-wavelength-emis sion RTP materials in aqueous solution remains a challenge.Here,we report red-emissive RTP materials via integration of the ring-fusing effect and host–guest interaction.

Conformational sensitivity of tetraphenyl-1,3-butadiene derivatives with aggregation-induced emission characteristics

Organic dyes with conformational sensitivity can be used to probe weak interactions at the molecular level.Here,three molecules based on tetraphenyl-1,3-butadienes(TPBs)were synthesized and studied with respect to their synthesis,structural characterization and potential application.All TPBs showed aggregation-induced emission(AIE)characteristics and sensitive conformational properties,in which the emission wavelengths could be changed in different states.The TPBs single crystals revealed that the phenyl groups at the 4-position of the 1,3-butadienes contributed to their conformational sensitivity.Furthermore,the potential application for monitoring the interactions among polyelectrolyte complexes and metal ions was explored,and the results showed that TPBs could be used for sensitively probing some weak interactions by changing the emission wavelengths due to their conformation-sensitive properties.TPBs may become a new star in AIE research fields.

Anthracene Modified by Aldehyde Groups Exhibiting Aggregation-Induced Emission Properties

In order to get an easy way to achieve the transformation from aggregation-caused quenching luminophores （ACQphores） to aggregation-induced emission luminogens （AIEgens）, we took aldehyde groups as the modifying group to decorate anthracene. The fluorescence performances of 9-anthraldehyde （AnA） and 9,10-anthracenedicarboxaldehyde （AnDA） in solution and aggregated state were studied. We found out that the aldehyde group can transform anthracene with aggregation-caused quenching properties to AIEgen. The single-crystal structures analy- sis of AnA and AnDA showed that their structure characteristics are responsible for the AIE properties of AnA and AnDA. On one hand, the aldehyde group can cause steric effects to lower intermolecular n-π packing style in aggregated state. On the other hand, intermolecular H-bonding interactions can restrict the intramolecular rotation and suppress internal charge transfer. These results may supply a new simple method for the transformation from ACQphores to AIEgens on the point of the molecular design.

Selective detection of phosphaphenanthrene-containing luminophors with aggregation-induced emission enhancement to transition metal ions

Transition metal ions(Pb^(2+),Zn^(2+),Cd^(2+),Co^(2+),Mn^(2+),Cu^(2+),Ni^(2+),Hg^(2+),Ag^(+),Fe^(3+))in water are used to quench emission of 2-(6-oxido-6H-dibenz<c,e><1,2>oxaphosphorin-6-yl)-1,4-phenylene-bis(p-pentyloxylbenzoate)s(MD5)with aggregation-induced emission enhancement(AIEE)in water-acetonitrile(AN)mixture(80:20 by volume).Among all metal ions,Fe^(3+)exhibits the highest quenching efficiency on AIEE of MD5 even when the concentration of Fe^(3+)is lower than 1×10^(-6) mol/L.The quenching efficiency of Hg^(2+)is lower than that of Fe^(3+)at the same concentration,though MD5 is used to detect Hg^(2+)efficiently,too.To other metal ions,low quenching efficiency has few relations with a wider concentration range.The UV absorbance spectra show only red shift of absorbance wavelength in the presence of Hg^(2+)and Fe^(3+),which indicates a salt-induced Jaggregation.SEM photos reveal larger aggregation and morphological change of nanoparticles of MD5 in water containing Hg^(2+)and Fe^(3+),which reduce the surface area of MD5 emission for further aggregation.The selective quenching effect of transition metal ions to emission of MD5 has a potential application in chemical sensors of some metal ions.