Macrotheranostic Probe with Disease‐Activated Near‐Infrared Fluorescence,Photoacoustic, and Photothermal Signals for Imaging‐Guided Therapy

Theranostics provides opportunities for precision cancer therapy. However, theranostic probes that simultaneously turn on their diagnostic signal and pharmacological action only in respond to a targeted biomarker have been less exploited. We herein report the synthesis of a macrotheranostic probe that specifically activates its near‐infrared fluorescence (NIRF), photoacoustic (PA), and photothermal signals in the presence of a cancer‐overexpressed enzyme for imaging‐guided cancer therapy. Superior to the small‐molecule counterpart probe, the macrotheranostic probe has ideal biodistribution and renal clearance, permitting passive targeting of tumors, in situ activation of multimodal signals, and effective photothermal ablation. Our study thus provides a macromolecular approach towards activatable multimodal phototheranostics.     

Low-temperature fabrication and photocatalytic activity of clustered TiO2 particles formed on glass fibers

Clustered anatase phase TiO₂ particles were uniformly formed on the surface of glass fibers by a liquid phase deposition (LPD) method at 60 °C using TiF₄ and H₃BO₃ as the precursors. The clustered TiO₂ particles deposited on the glass fibers and as a photocatalyst these particles not only have a larger surface area than TiO₂ thin films, but also can avoid the disadvantages of using TiO₂ powders encountered in air purification or water treatment. The photocatalytic activity of the sample was evaluated by the photocatalytic oxidation of nitrogen monoxide (NO) in the gaseous phase. The deposition conditions and chemical composition of the clustered TiO₂ particles were discussed. It was found that the clustered TiO₂ particles that formed on the glass fibers obviously showed photocatalytic activity without high-temperature calcination. A formation mechanism was proposed to account for the formation of TiO₂ clustered morphology on the glass fibers.     

Tailored Zwitterionic Hemicyanine Reporters for Early Diagnosis and Prognostic Assessment of Acute Renal Failure

Drug-induced renal failure (DIRF) poses a serious medical complication with high mortality risk. However, early diagnosis or prognosis of DIRF remain challenging, as current methods rely on detecting late-stage biomarkers. Herein we present a library of zwitterionic unimolecular hemicyanines (ZCs) available for constructing activatable reporters to detect DIRF since its initial stage. Zwitterionic properties of these probes are achieved through interspersedly integrating alkyl sulfonates and quaternary ammonium cations onto hemicyanine skeleton, which result in record low plasma protein binding (<5 %) and remarkable renal clearance efficiencies (≈96 %). An activatable reporter ZCRR is further developed by masking the optimal candidate ZC6 with a tetrapeptide specifically cleavable by caspase-8, an initiating indicator of apoptosis. In living mice with cisplatin-induced DIRF, systematically administered ZCRR efficiently accumulates in kidneys and responds to elevated caspase-8 for near-infrared fluorescence signals ‘turn-on’, enabling sensitive detection of intrarenal apoptosis 60 h earlier than clinical methods, and precise evaluation of apoptosis remediation effects by different medications on DIRF mice. As it's urinary excretable, ZCRR also allows for remote detection of DIRF and predicting renoprotective efficacy through in vitro optical urinalysis. This study thus presents unimolecular renal clearable scaffolds that are applicable to developing versatile activatable reporters for renal diseases management.     

质子酸的酸性强弱比较

酸碱质子理论是大学无机化学教学中最重要的概念之一,溶液中的酸碱强弱的比较虽然可以通过查找酸碱解离常数来得到,但在数据缺失情况下的定性比较酸碱强弱在教学中也很重要,而且这种比较可以帮助学生理解物质结构与性质之间的相关性。本文根据质子酸碱的化学组成和分子结构分析它们的酸碱性,并主要根据分子结构信息,包括键的极性、键的强度、键的离域、氢键、分子中键的环境等,推导、比较它们酸碱性的相对强弱。     

Semiconducting Polymer Nanoenzymes with Photothermic Activity for Enhanced Cancer Therapy

Regulation of enzyme activity is fundamentally challenging but practically meaningful for biology and medicine. However, noninvasive remote control of enzyme activity in living systems has been rarely demonstrated and exploited for therapy. Herein, we synthesize a semiconducting polymer nanoenzyme with photothermic activity for enhanced cancer therapy. Upon near‐infrared (NIR) light irradiation, the activity of the nanoenzyme can be enhanced by 3.5‐fold to efficiently digest collagen in the tumor extracellular matrix (ECM), leading to enhanced nanoparticle accumulation in tumors and consequently improved photothermal therapy (PTT). This study thus provides a promising strategy to remotely regulate enzyme activity for cancer therapy.     

Hierarchically nanostructured porous TiO<Subscript>2</Subscript>(B) with superior photocatalytic CO<Subscript>2</Subscript> reduction activity

Hierarchically nanostructured, porous TiO₂(B) microspheres were synthesized by a microwave-assisted solvothermal method combined with subsequent heat treatment in air. The materials were carefully characterized by scanning and transmission electron microscopy, X-ray diffraction, CO₂ adsorption, and a range of spectroscopies, including Raman, infrared, X-ray photoelectron and UV-Vis spectroscopy. The hierarchical TiO₂(B) particles are constructed by ultrathin nanosheets and possess large specific surface area, which provided many active sites for CO₂ adsorption as well as CO₂ conversion. The TiO₂(B) nanostructures exhibited marked photocatalytic activity for CO₂ reduction to methane and methanol. Anatase TiO₂ and P₂5 were used as the reference photocatalysts. Transient photocurrent measurement also proved the higher photoactivity of TiO₂(B) than that of anatase TiO₂. In-situ infrared spectrum was measured to identify the intermediates and deduce the conversion process of CO₂ under illumination over TiO₂(B) photocatalyst.     

Near-infrared fluorescent molecular probes for imaging and diagnosis of nephro-urological diseases

Near-infrared (NIR) fluorescence imaging has improved imaging depth relative to conventional fluorescence imaging in the visible region, demonstrating great potential in both fundamental biomedical research and clinical practice. To improve the detection specificity, NIR fluorescence imaging probes have been under extensive development. This review summarizes the particular application of optical imaging probes with the NIR-I window (700–900 nm) or the NIR-II window (1000–1700 nm) emission for diagnosis of nephron-urological diseases. These molecular probes have enabled contrast-enhanced imaging of anatomical structures and physiological function as well as molecular imaging and early diagnosis of acute kidney injury, iatrogenic ureteral injury and bladder cancer. The design strategies of molecular probes are specifically elaborated along with representative imaging applications. The potential challenges and perspectives in this field are also discussed.

Near-infrared fluorescent molecular probes with improved imaging depth and optimized biodistribution have been reviewed, showing great potential for diagnosis of nephro-urological diseases.     

Preface to Special Issue for Chinese Symposium on Photocatalytic Materials (CSPM)

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Renal‐clearable Molecular Semiconductor for Second Near‐Infrared Fluorescence Imaging of Kidney Dysfunction

Real‐time imaging of kidney function is important to assess the nephrotoxicity of drugs and monitor the progression of renal diseases; however, it remains challenging because of the lack of optical agents with high renal clearance and high signal‐to‐background ratio (SBR). Herein, a second near‐infrared (NIR‐II) fluorescent molecular semiconductor (CDIR2) is synthesized for real‐time imaging of kidney dysfunction in living mice. CDIR2 not only has a high renal clearance efficiency (≈90 % injection dosage at 24 h post‐injection), but also solely undergoes glomerular filtration into urine without being reabsorbed and secreted in renal tubules. Such a unidirectional renal clearance pathway of CDIR2 permits real‐time monitoring of kidney dysfunction in living mice upon nephrotoxic exposure. Thus, this study not only introduces a molecular renal probe but also provides useful molecular guidelines to increase the renal clearance efficiency of NIR‐II fluorescent agents.