Use of Radioiodinated Peptide Arg-Arg-Leu Targeted to Neovascularization as well as Tumor Cells in Molecular Tumor Imaging

Objective： To explore a tumor peptide imaging agent Arginine-Arginine-Leucine （Tyr-Cys-Gly-Gly-Arg-Arg- Leu-Gly-Gly-Cys, tripeptide RRL [tRRL]） that targeted to tumor cells and tumor-derived endothelial cells （TDECs） and primarily investigate the possible relationship between tRRL and vascular endothelial growth factor receptor 2 （VEGFR-2）. Methods： The tRRL sequence motif was identified as a tumor molecular marker specifically binding to TDECs. Tyrosine was conjugated to the amino terminal of RRL （Cys-Gly-Gly-Arg-Arg-Leu-Gly-Gly-Cys） for labeling with radionuclide iodine-131 （1311-tRRL）. The uptake ability and molecular binding of tRRL to tumor cells and angiogenic endothelium were studied using flow cytometry and radioactivity counter in vitro. Whether VEGFR-2 is the binging site of tRRL was investigated. Biodistribution and single-photon emission computed tomography （SPECT） imaging of 131-tRRL were used to evaluate the effectiveness of this new imaging agent to visualize varied tumor xenografts in nude mice. Results： In vitro cellular uptake experiments revealed that tRRL could not only adhere to tumor angiogenic endothelial cells but also largely accumulate in malignant tumor cells. VEGFR-2, which is highly expressed on TDECs, was probably not the solely binding ligand for tRRL targeted to tumor angiogenic endothelium, 131-tRRL mainly accumulated in tumors in vivo, not other organs at 24 h after injection. SPECT imaging with 131-tRRL clearly visualized tumors in nude mice, especially at 24 h. Conclusion： Radioiodinated tRRL offers a noninvasive of tumors targeted to neovascularization, and may be a carrier. nuclear imaging method for functional molecular imaging promising candidate for tumor radioimmunotherapeutic carrier,

Potential application of neogalactosylalbumin in positron emission tomography evaluation of liver function

AIM To investigate the evaluation of neogalactosylalbumin (NGA) for liver function assessment based on positron emission tomography technology. METHODS Female Kunming mice were assigned randomly to two groups: fibrosis group and normal control group. A murine hepatic fibrosis model was generated by intraperitoneal injection of 10% carbon tetrachloride (CCl4) at 0.4 ml every 48 h for 42 d. F-18-labeled NGA ([F-18] FNGA) was synthesized and administered at a dosage of 3.7 MBq/mouse to both fibrosis mice and normal control mice. Distribution of [F-18] FNGA amongst organs was examined, and dynamic scanning was performed. Parameters were set up to compare the uptake of tracers by fibrotic liver and healthy liver. Serologic tests for liver function were also performed. RESULTS The liver function of the fibrosis model mice was significantly impaired by the use of CCl4. In the fibrosis model mice, hepatic fibrosis was verified by naked eye assessment and pathological analysis. [F-18] FNGA was found to predominantly accumulate in liver and kidneys in both control group (n = 21) and fibrosis group (n = 23). The liver uptake ability (LUA), peak time (T-p), and uptake rate (LUR) of [F-18] FNGA between healthy liver (n = 8) and fibrosis liver (n = 10) were significantly different (P < 0.05, < 0.01, and < 0.05, respectively). LUA was significantly correlated with total serum protein level (TP) (P < 0.05). T-p was significantly correlated with both TP and glucose (Glu) concentration (P < 0.05 both), and LUR was significantly correlated with both total bile acid and Glu concentration (P < 0.01 and < 0.05, respectively). CONCLUSION [F-18] FNGA mainly accumulated in liver and remained for sufficient time. Functionally-impaired liver showed a significant different uptake pattern of [F-18] FNGA compared to the controls.

Flexible Crystal Heterojunctions of Low-Dimensional Organic Metal Halides Enabling Color-Tunable Space-Resolved Optical Waveguides

Molecular luminescent materials with optical waveguide have wide application prospects in light-emitting diodes, sensors, and logic gates. However, the majority of traditional optical waveguide systems are based on brittle molecular crystals, which limited the fabrication, transportation, storage, and adaptation of flexible devices under diverse application situations. To date, the design and synthesis of photofunctional materials with high flexibility, novel optical waveguide, and multi-port color-tunable emission in the same solid-state system remain an open challenge. Here, we have constructed new types of zero-dimensional organic metal halides (Au-4-dimethylaminopyridine [DMAP] and In-DMAP) with a rarely high elasticity and rather low loss coefficients for optical waveguide. Theoretical calculations on the intermolecular interactions showed that the high elasticity of 2 molecular crystalline materials was original from their herringbone structure and slip plane. Based on one-dimensional flexible microrods of 2 crystals and the 2-dimensional microplate of the Mn-DMAP, heterojunctions with multi-color and space-resolved optical waveguides have been fabricated. The formation mechanism of heterojunctions is based on the surface selective growth on account of the low lattice mismatch ratio between contacting crystal planes. Therefore, this work describes the first attempt to the design of metal-halide-based crystal heterojunctions with high flexibility and optical waveguide, expanding the prospects of traditional luminescent materials for smart optical devices, such as logic gates and multiplexers.

Comparison of quality control standards of PET radiopharmaceuticals for tumor in Pharmacopoeia of Europe,the United States and People’s Republic of China

To improve the relevant methods of the quality control standards of tumor Positron Emission Computed Tomography(PET)radiopharmaceuticals and to reduce the clinical application risks of such drugs,this article compares and analyzes the similarities and differences of the quality control standards of tumor PET radiopharmaceuticals in the Pharmacopoeia of People’s Republic of China(ChP2020),European Pharmacopoeia(EP8.0)and United States Pharmacopoeia(USP39),focusing on comparing and analyzing the identification(identification method),inspection(pH,residual solvent,bacterial endotoxin,sterility,and impurities),and content determination(radionuclear purity,radiochemical purity,and radioactive concentration)of tumor PET radiopharmaceuticals.The quality control standards of ChP2020 for tumor PET radiopharmaceuticals are relatively equivalent to the quality control standards of USP39 but are not as stringent as those of EP8.0.In general,EP8.0 has the most comprehensive and strict quality control standards for tumor PET radiopharmaceuticals.The quality control standards of tumor PET radiopharmaceuticals in the Chinese Pharmacopoeia can be improved by referring to international standards,especially the European Pharmacopoeia.

Fluorescent probes for detection of biothiols based on “aromatic nucleophilic substitution-rearrangement” mechanism

Biothiols,including cysteine(Cys),homocysteine(Hey),and glutathione(GSH) play important roles in physiological processes,and the detection of thiol using fluorescent probes has attracted attention due to their high sensitivity and selectively and invasive on-time imaging.However,the similar structures and reactivity of these biothiols present great challenges for selective detection.This review focused on the the "aromatic nucleophilic substitution-rearrangement(SNAr-rearrangement) mechanism",which provided a powerful tool to design fluorescent probes for the discrimination between biothiols.We classify the fluorescent probes according to types of fluorophores,such as difluoroboron dipyrromethene(BODIPY),nitrobenzoxadiazole(NBD),cyanine,pyronin,naphthalimide,coumarin,and so on.We hope this review will inspire exploration of new fluorescent probes for biothiols and other relevant analytes.

Accelerated plasma degradation of organic pollutants in milliseconds and examinations by mass spectrometry

The rapid degradation of organic pollutants,process monitoring and online controlling to obtain advanced products and decreased by-products are great and challenging tasks in environmental treatments.Herein,an accelerated plasma degradation in milliseconds was achieved by combining electrospray-based acceleration and plasma-based degradation.Taking the degradation of chloroaniline as an example,97%of the degradation can be achieved in milliseconds.The velocity distribution of droplets was determined to be 40-50 m/s after being degraded for 0.30 ms,which exhibited different degradation behaviors in different milliseconds.Simultaneously,by virtue of the real-time and on-line detection ability of ambient mass spectrometry,intermediates,by-products and advanced products were monitored.Therefore,degradation mechanisms for different degradation times were proposed,which would provide theoretical guidance on obtaining efficient and green degradation.The fabrication,examining and understanding of accelerated plasma degradation not only enlarged application of accelerated reactions,but also promoted green and efficient degradation for environmental treatments.

[12] ane N_3-based BODIPY as a selective and sensitive off–on sensor for the sequential recognition of Cu^(2+) ions and ADP

A new [12]aneN3-based BODIPY sensor I showed highly selective and sensitive recognition of Cu2~ ions through fluorescence quenching effect in aqueous solution. The above copper complex solution can further be used as a turn-on fluorescent probe for detecting ADP with high selectivity, and also applied in imaging of living cells.

Synthesis and biological evaluation of ^(99m)Tc-HEDTA/HYNIC-MPP4 complex for 5-HT_(1A) receptor imaging

5-HT_(1A)receptor is associated with a variety of pathophysiology of neuropsychiatric disorders.Accordingly,we have synthesized a new 5-HT_(1A) receptor ligand(HYNIC-MPP4)and labeled it with^(99m)Tc using N-(2-hydroxyethyl)ethylenediaminetriacetic acid(HEDTA)as coligand.^(99m)Tc-HEDTA/HYNIC-MPP4 was prepared under pH 6 at room temperature.Biodistribution of^(99m)Tc-HEDTA/HYNIC-MPP4 in normal mice showed that this complex had moderate brain uptake(0.60%ID·g^(-1)at 2 min p.i.)and good retention.The hippocampus had the highest radioactivity uptake at 2 min p.i.(1.84%ID·g^(-1)).The ratio of Hipp/CB was 3.1 at 2 min p.i.and increased to 4.4 at 60 min p.i.After blocking with 8-hydroxy-2-(dipropylamino)tetralin,the uptake of hippocampus was decreased significantly from 1.84%ID·g^(-1) to 0.53%ID·g^(-1) at 2 min p.i.,while the cerebellum had no significant decrease.This^(99m)Tc complex could be a potent agent for 5-HT_(1A) receptor imaging.

In situ localization of BiVO_(4) onto two-dimensional MXene promoting photoelectrochemical nitrogen reduction to ammonia

The existing industrial ammonia synthesis usually adopts the Haber-Bosch process,which requires harsh conditions of high temperature and high pressure,and consumes high energy.Under this circumstance,photoelectrochemical(PEC)catalysis is regarded as a promising method for N_(2) reduction reaction(NRR),but bears problems of low efficiency and yield.Thus,exploring active catalysts remains highly desirable.In this work,BiVO_(4)@MXene hybrids have been facilely synthesized by a hydrothermal route.The heterojunctions by the in situ growth of BiVO_(4) onto two-dimensional(2D)MXene greatly increase the NRR efficiency:under photoelectric conditions,the optimized NH_(3) yield is 27.25µg h^(-1) cm^(-2),and the Faraday efficiency achieves 17.54% at−0.8 V relative to the reversible hydrogen electrode(RHE),which are higher than most state-of-the-art NRR(photo)electrocatalysts.The mechanism speculation shows the enhanced light absorption range and the heterojunction formation largely promote the separation and the transfer efficiency of photogenerated carriers,thereby improving the PEC catalytic ability.Therefore,this work provides a hybrid route to combine the advantages of photo and electric catalysis for effective artificial nitrogen fixation.

长余辉发光中载流子陷阱态的作用

As one of the most promising forms of light-emitting,long-persistent luminescence(LPL),that was first observed in ancient luminous pearls from the Yan dynasty in China,continues to exhibit renewed vitality across a wide range of optoelectronic applications,encompassing optical display,bioimaging,photonic technologies and photocatalysis in modern society[1].

Gold complex showing chiral persistent luminescence

Long-persistent luminescence(LPL)has received significant focus due to its exceptional applications in high-contrast molecular imaging,photodynamic therapy,data encryption and information storage,and among many others^([1]).Ultralong room-temperature phosphorescence(RTP),as a form of LPL.

On-demand molecular design for efficient blue phosphorescence

Blue luminescence(including both fluorescence and phosphorescence)is one of the core elements in solid-state lighting and full-color displays.Up to now,ultralong room temperature phosphorescence(RTP)with a long lifetime over 0.1 s has been continuously reported.Most ultralong phosphorescence emission bands are in the region of 500 to600 nm.However,high-energy blue phosphorescence remains an immense challenge[1].

Supramolecular glass:a new platform for ultralong phosphorescence

Materials exhibiting persistently ultralong room-temperature phosphorescence(RTP)are capturing significant attention due to their long lifetimes,pronounced Stokes shifts,and efficient exciton utilization[1–3].These attributes position RTP materials as ideal candidates for advanced applications in information security,data storage,light-emitting diodes,bioimaging[4–6].

A Review on Nanomaterial-based Strategies for Manipulating Tumor Microenvironment to Enhance Chemodynamic Therapy

Cancer is a leading cause of death worldwide,and a series of strategies has been reported for tumor-specific therapy.Currently,chemodynamic therapy(CDT)has become a research hotspot for antitumor treatment due to its advantages of high specificity,endogenous stimulation,and high biosafety.However,the therapeutic effects of CDT are normally limited in the complex tumor microenvironment(TME),such as insufficient acidity,tumor hypoxia,low hydrogen peroxide(H2O2),and high glutathione(GSH).Consequently,different kinds of multifunctional nanomaterials have been designed to manipulate TME conditions,which provided more opportunities to improve the efficiency of CDT.This review focuses on nanomaterial-based strategies for enhancing CDT through manipulating TME.Upon CDT enhancements,this review would provide a reference for the future development of efficient CDT nanomaterials.

利用室温磷光碳点提供的超长寿命三重态激子促进石墨相氮化碳的光催化性能

半导体光催化剂目前受到了广泛的关注与研究,但其光生电子和空穴的复合导致能量损失,制约着这类催化剂的应用.本工作利用具有超长寿命的三重态激子来促进电子和空穴对的有效分离,以产生更多的自由载流子.与传统的荧光碳点(CD)相比,高度分散在石墨相氮化碳上的室温磷光(RTP)碳点显示出显著提升的光催化能力和电化学活性.实验和理论计算都表明,RTP CD@g-C_(3)N_(4)可以作为“能量缓释胶囊”,不断提供长寿命的三重态激子,从而有效地调控电子和空穴对的解离,并增强催化剂固有的光催化性能(包括水分解和染料降解反应).本工作提供了一种将超长寿命三重态激子用作光催化剂的设计思路.

长余辉杂化钙钛矿

Long-afterglow phosphors are a class of promising photofunctional materials in many application areas involving security encryption,bioimaging,sensors,data storage,and decoration,due to their persistent photoemission and light storage ability[1].For traditional all-inorganic oxide-,sulfide-,and nitride-based phosphors,the afterglow emission is determined by the host lattice with the luminescent centers and trapping states,which exhibit long persistent luminescence up to several hours or even days after removing the light excitation(Fig.1a)[2].

Peptide-assembled siRNA nanomicelles confine MnOx-loaded silicages for synergistic chemical and gene-regulated cancer therapy

Chemodynamic therapy(CDT) is a promising therapeutic approach for in situ cancer treatment, but it is still hindered by inefficient single-modality treatment and the weak targeted delivery of reagents into mitochondria(the main site of intracellular ROS production). Herein, to obtain a multimodal strategy,peptide-assembled si RNA nanomicelles were prepared to confine ultrasmall MnOxin small silica cages(silicages), which is convenient for synergistic chemical and gene-regulated cancer therapy. Given the free energy and versatility of small silicages, as well as the excellent Fenton-like activity of ultrasmall MnOx,MnOx-inside-loaded silicages(10 nm) were prepared for CDT delivery to mitochondria. Subsequently, to obtain a synergistic CDT and gene silencing treatment, the peptide-mediated assembly of si RNA and MnOx-loaded silicages were employed to obtain silicage@MnOx-si RNA nanomicelles(SMS NMs). After multiple modifications, sequential cancer cell-targeted delivery, GSH-controlled reagent release of si RNA and mitochondria-targeted delivery of MnOx-loaded silicages were successfully achieved. Finally, by both in vitro and in vivo experiments, SMS NMs were confirmed to be effective for synergistic chemical and gene-regulated cancer therapy. Our findings expand the applications of silicages and initiate the development of multimodal CDT.

Dynamic multi-color long-afterglow and cold-warm white light through phosphorescence resonance energy transfer in host-guest metal-organic frameworks

Dynamic tuning of single-color and multi-color(including white-light) luminescence has attracted much attention for applications in various fields;however, effective systems are still scarcity to date. Herein, we report the construction of host-guest metal-organic frameworks(MOFs) serves as an effective strategy to achieve the excitation-and time-dependent long afterglow and white light emitting, simultaneously. The guest-induced structural distortion modulates the single-triplet state intersystem crossing, promotes ligand-to-ligand charge transfer(LLCT) in layer-column MOFs, and further boosts multiple exciton generation of triplet states for multi-color ultralong phosphorescence, as indicated by both experiment and density functional theory(DFT) calculation. By further doping of dyes into MOFs, white-light emitting with tunable color temperature can be facilely obtained, which has been further fabricated into white-light light-emitting diode(LED) with color rendering index of 88.4,higher than that of most as-reported pure inorganics and inorganic-organic hybrid systems. Therefore, this work not only describes a host-guest energy transfer route for dynamic tailoring wide range of color-tunable long-afterglow, but also explores the application prospect of new white-light materials with high color rendering and low blue light for promising display and lighting applications.

Colorful ultralong room-temperature phosphorescence in dual-ligand metal-organic framework

Long afterglow organic-inorganic hybrid materials have attracted much attention in recent years and are widely used in information security, biological imaging and many other fields. Since up-conversion long-persistence materials are promising for bio-optical imaging due to their high penetration depth and elimination of autofluorescence background, it is highly desirable to combine down-conversion and up-conversion pathways to obtain smart materials with excitation-dependent tunable room-temperature phosphorescence properties. In this work, a metal-organic framework(Zn-DCPS-BIMB), consisting of divalent zinc ions, o-bis(imidazol-1-ylmethyl)benzene and 4,4-dicarboxydiphenylsulfone, is designed to stabilize triplet excitons, coordinate the emission of different ligands, and endow materials with tunable emission color and up-conversion properties via heavy atoms effects promoting single-triplet orbital coupling and intersystem crossing.

Brightening room-temperature phosphorescence in solution

The strategies including noncovalent macrocycle-confined supramolecular assembly and construction of rigid hydrogen-bond network have been verified as effective routes to brighten aqueous-phase room temperature phosphorescence.Molecule-based room-temperature phosphorescence(RTP)has attracted widespread attention in the fields of chemical sensors,optical anti-counterfeiting,information encoding and so on,due to unique characteristics of long excited-state lifetimes,large Stokes shifts and high signal-tonoise ratios[1,2].Currently,to obtain RTP with considerable efficiency and long lifetime,two brilliant strategies have been developed:one is the introduction of heavy atoms,which facilitates the spin-orbital coupling and intersystem crossing(ISC)from singlet to triplet states。