Light-driven sextuple theranostics:nanomedicine involving second near-infrared AIE-active Ir(Ⅲ)complex for prominent cancer treatment

Light-driven cancer theranostics has shown inexhaustible and vigorous vitality by virtue of its high efficacy,prominent controllability and noninvasiveness.Exploration of an all-round theranostic material simultaneously affording both multimodal diagnosis imaging and synergistic phototherapy would be an appealing yet significantly challenging task.Herein,a novel nanomedicine Ir@PPEG-MeEPO was ingeniously constructed by integrating beforehand1O2-charged amphiphilic polymer and well-tailored Ir(Ⅲ)complex IrDPTP,which was featured by second near-infrared(NIR-Ⅱ)aggregation-induced emission(AIE)tendency,efficient reactive oxygen species(ROS)generation,good photothermal conversion efficiency and high-performance hydrogen gas production.To the best of our knowledge,IrDPTP held the longest emission wavelength among all reported AIE Ir(Ⅲ)complexes.Moreover,Ir@PPEG-MeEPO was capable of controllably releasing ROS via triggered photothermal effect upon NIR irradiation,making it well-adapted to hypoxic environment of tumor.Those distinctive characteristics of Ir@PPEG-MeEPO endowed it with unprecedented performance on sextuple theranostics comprised of NIR-Ⅱfluorescence-photoacoustic-photothermal trimodal imaging and photodynamic-photothermal-hydrogen trimodal therapy,witnessed by the precise tumor diagnosis and complete tumor elimination.The study would open up new perspectives for the exploration of superior nanomedicine for practical cancer theranostics.

Recent progress in diagnostic imaging and therapeutics of osteosarcoma based on multifunctional nanoparticles

Osteosarcoma is one of the most common primary bone malignancies,mainly occurring in children and adolescents.Traditional diagnosis imaging methods for osteosarcoma contain X-ray,computed tomography and magnetic resonance imaging,and traditional therapy protocols are surgical resection and chemotherapy.However,these strategies are complicated and separated.These imaging methods,despite their maturity,have drawbacks that prevent them from showing more details.What is more,the prognosis for patients with osteosarcoma remains unsatisfactory due to side effects of chemotherapy,as well as incomplete surgical removal of the tumor.To compensate for the shortcomings of traditional imaging and treatment strategies for osteosarcoma,various types of nanoparticles have been designed and synthesized to selectively target osteosarcoma cells without toxic side effects on healthy organs.At the same time,these nanoparticle-based technologies can integrate the imaging and treatment of osteosarcoma.This review summarizes the application of nanotechnology in the imaging and treatment of osteosarcoma in recent years,and finally discusses the challenges and development prospects,aiming to provide ideas for future research.

Aggregation-Induced Emission:A Rising Star in Chemistry and Materials Science

Aggregation-induced emission(AIE)refers to a photophysical effect that the luminescence of aggregates is stronger than that of the dispersed state.Since the concept of AIE was coined by Professor Ben Zhong Tang and co-workers in 2001,AIE has evolved from a simple luminescent phenomenon to a multidisciplinary research field with a widespread influence.It has changed people's way of thinking about chromophore aggregation and greatly promoted the development of advanced luminescent materials.During the 20-year development,diverse AIE luminogens(AlEgens)with attractive functionalities have been developed and remarkable achievements have been made in the mechanistic study and high-tech applications of AlEgens.In this review,we provide an overview of the historical development and representative achievements of AIE research.Perspectives on the application of AIE in aggregate science are also briefly discussed to guide the future development in this field.

Strategies for Improving the Brightness of Aggregation-Induced Emission Materials at Aggregate Level

The brightness of fluorescent agents directly determines the imaging performance as required.Among various fluorophores,small organic species are promising given its exact purity/composition and excellent processibility.However,chromophores with planar geometry may suffer from the undesirable aggregation-caused quenching(ACQ)phenomenon.Encouragingly,luminogens showing aggregation-induced emission(AIE)features are preferable as the aggregates which are the most common used state.In this review,we mainly focus on the strategies employed for boosting the brightness of AIE-active luminogens(AIEgens).From molecule to mor-phology levels,approaches that regulate electronic transition processes of the molecule or the packing extent of aggregates in order to confine molecular motion,reduceπ-πstacking,disrupt fluorophore-water interactions,etc.,are presented.In the end,the current challenges and perspectives are briefly discussed.We anticipate that this review will stimulate new insights and more efforts for the advancement of ultrabright AIEgens.

Near-infrared emissive AIE nanoparticles for biomedical applications:From the perspective of different nanocarriers

Fluorescent imaging based on near-infrared(NIR)fluorophores has revolutionized the techniques employed for detecting biological events in depth owing to their advantages referring to diminished photon scattering,high signal-to-noise ratio and better light transparence through tissue.As for conventional luminogens,the nanofabrication of those innately hydrophobicπ-conjugated architectures into water-dispersible nanoparticles(NPs)may result in attenuated fluorescent intensity deriving from the detrimental distribution ofπ-πinteractions in the confined space.Oppositely,chromophores possessing aggregation-induced emission(AIE)characteristics emit boosted brightness at aggregate level according to the mechanism of restriction of intramolecular motion(RIM).In this review,we summarize the recent progresses of NIR emissive AIE NPs for multifarious biomedical applications from the viewpoint of different fabricated manners,mainly covering self-assembly and matrices assisted approaches.Furthermore,the current challenges and future research directions of NIR AIE NPs are briefly discussed.