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Carbon nanomaterials have received great attention from the scientific community over the past few decades because of their unique physical and chemical properties. In this minireview, we will summarize the recent progress of the use of various carbon nanomaterials in the field of cancer phototherapy. The structural characteristics of each category and the surface functionalization strategies of these nanomaterials will be briefly introduced before focusing on their therapeutic applications. Recent advances on their use in photothermal therapy, photodynamic therapy, and combined phototherapies are presented. Moreover, a few challenges and perspectives on the development of carbon nanomaterials for future theranostics are also discussed. The many dimensions of carbon nanomaterials: The recent progress of carbon nanomaterials in the field of cancer phototherapy is reviewed. A few challenges, perspectives on the development of carbon nanomaterials for future phototheranostics are also discussed. [ABSTRACT FROM AUTHOR]

Abstract Application of carbon nanomaterials to near-infrared light-mediated phototherapy has attracted great interest. However, their practical use in biological systems is severely limited by their poor water dispersibility, inevitable adsorption of plasma proteins, and their single therapeutic function. Herein, we prepared a phycocyanin (PC)-functionalized single-walled carbon nanohorns (PC@SWNHs) hybrid, where PC is used to preform a protein corona around the SWNHs through non-covalent interface interactions. In the PC@SWNHs, the preformed PC corona effectively improves the water dispersibility of the SWNHs and protects them from plasma protein adsorption. In addition, the excellent photodynamic activity of PC overcomes the inability of SWNHs to generate reactive oxygen species. The SWNHs not only give the hybrid a photothermal therapy (PTT) function, but they also enhance the photostability of PC. These characteristics of the PC@SWNHs are confirmed by in vitro and in vivo experiments, where synergistic photodynamic therapy (PDT)/PTT growth inhibition of tumors is achieved. The PC@SWNHs also act as a photoacoustic/thermal imaging agent to visualize the in vivo treatment process. Hence, this work not only paves the way to use the complementarity between SWNHs and proteins for multifunctional cancer theranostics, but it also allows for a better understanding of bio–nano interface interactions between them. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

The surface functionalization of carbon dots (CDs) can introduce an additional dimension for the control of their photoluminescence properties and effective promotion of the applications of CDs such as imaging, sensing, etc . In this study, a simple one-step carbonization using Tween 80 as the sole carbon source is described for directly synthesizing white-emitting CDs (WCDs) in high yield. The results revealed the presence of several long alkyl chains on the surface of the as-fabricated WCDs, which effectively suppress the aggregation-caused quenching (ACQ) effect and emit bright white luminescence under an UV illumination of 365 nm in the solution and solid states. Besides, together with the surface protection of long alkyl chains, WCDs preferentially interact with lipophilic fatty residues and are beneficial for the label-free imaging of latent fingerprints. This study provides a promising new method to not only effectively inhibit the intrinsic ACQ effect of CDs but also develop the surface engineering of functionalized white-emitting CDs for practical applications via facile synthesis. [ABSTRACT FROM AUTHOR]

Due to the difficulty of accurately characterizing properties such as the molecular weight (Mn) and grafting density (σ) of gradient brushes (GBs), these properties are traditionally assumed to be uniform in space to simplify analysis. Applying a stochastic reaction model (SRM) developed for heterogeneous polymerizations, we explored surface-initiated polymerizations (SIPs) with initiator gradients in lattice Monte Carlo simulations to examine this assumption. An initial exploration of SIPs with 'homogeneously' distributed initiators revealed that increasing σ slows down the polymerization process, resulting in polymers with lower molecular weight and larger dispersity (Đ) for a given reaction time. In SIPs with an initiator gradient, we observed that the properties of the polymers are position-dependent, with lower Mn and larger Đ in regions of higher σ, indicating the non-uniform properties of polymers in GBs. The results reveal a significant deviation in the scaling behavior of brush height with σ compared to experimental data and theoretical predictions, and this deviation is attributed to the non-uniform Mn and Đ. [ABSTRACT FROM AUTHOR]

Hypoxia is a critical factor for restricting photodynamic therapy (PDT) of tumor, and it becomes increasingly severe with increasing tissue depth. Thus, the relief of deep tumor hypoxia is extremely important to improve the PDT efficacy. Herein, tumor microenvironment (TME)‐responsive size‐switchable hyaluronic acid‐hybridized Ru nanoaggregates (HA@Ru NAs) were developed via screening reaction temperature to alleviate deep tumor hypoxia for improving the tumor‐specific PDT by the artful integration multiple bioactivated chemical reactions in situ and receptor‐mediated targeting (RMT). In this nanosystem, Ru NPs not only enabled HA@Ru NAs to have near infrared (NIR)‐mediated photothermal/photodynamic functions, but also could catalyze endogenous H2O2 to produce O2in situ. More importantly, hyaluronidase (HAase) overexpressed in the TME could trigger disassembly of HA@Ru NAs via the hydrolysis of HA, offering the smart size switch capability from 60 to 15 nm for enhancing tumor penetration. Moreover, the RMT characteristics of HA ensured that HA@Ru NAs could specially enter CD44‐overexpressed tumor cells, enhancing tumor‐specific precision of phototherapy. Taken together these distinguishing characteristics, smart HA@Ru NAs successfully realized the relief of deep tumor hypoxia to improve the tumor‐specific PDT. [ABSTRACT FROM AUTHOR]

To better characterize the properties of surface-initiated polymers, simultaneous bulk- and surface-initiated polymerizations are usually carried out by assuming that the properties of the surface-initiated polymers resemble those of the bulk-initiated polymers. Through a Monte Carlo simulation using a heterogeneous stochastic reaction model, it was discovered that the bulk-initiated polymers exhibit a higher molecular weight and a lower dispersity than the corresponding surface-initiated polymers, which indicates that the equivalent assumption is invalid. Furthermore, the molecular weight distributions of the two types of polymers are also different, suggesting different polymerization mechanisms. The results can be simply explained by the heterogeneous distributions of reactants in the system. This study is helpful to better understand surface-initiated polymerization. [ABSTRACT FROM AUTHOR]

The structural characteristics of various carbon nanomaterials, their surface functionalization strategies, and recent advances in the field of cancer phototherapy are summarized in the Minireview by X.‐C. Shen et al. on page 3993 ff. Their excellent NIR absorption, large surface area, and appropriate size make carbon nanomaterials attractive and promising nanoplatforms for phototherapeutic applications. Despite many significant advances in this field have been made, several challenges remain to be addressed to promote their practical clinical applications. [ABSTRACT FROM AUTHOR]

The mechanism of the surface chemistry of carbon dots (CDs) is revealed in the solid state by X.‐C. Shen and co‐workers in the Full Paper on page 18993 ff. Red‐emitting CDs (RCDs) are prepared, and further used to serve as solid‐state fluorescence sensory material for gaseous ammonia. More importantly, they confirm that the fluorescence response of the RCDs results from ammonia‐induced Michael addition via insertion of N into the CC group and deprotonation of the carboxyl group. [ABSTRACT FROM AUTHOR]

The stochastic reaction model (SRM) treats polymerization as a pure probability‐based issue, which is widely applied to simulate various polymerization processes. However, in many studies, active centers were assumed to react with the same probability, which cannot reflect the heterogeneous reaction microenvironment in heterogeneous polymerizations. Recently, we have proposed a simple SRM, in which the reaction probability of an active center is directly determined by the local reaction microenvironment. In this paper, we compared this simple SRM with other SRMs by examining living polymerizations with randomly dispersed and spatially localized initiators. The results confirmed that the reaction microenvironment plays an important role in heterogeneous polymerizations. This simple SRM provides a good choice to simulate various polymerizations. [ABSTRACT FROM AUTHOR]

Herein, we describe an energy balance strategy between fluorescence and photoacoustic effects by sulfur substitution to transform existing hemicyanine dyes (Cy) into optimized NIRF/PA dual ratiometric scaffolds. Based on this optimized scaffold, we reported the first dual‐ratio response of nitroreductase probe AS‐Cy‐NO2, which allows quantitative visualization of tumor hypoxia in vivo. AS‐Cy‐NO2, composed of a new NIRF/PA scaffold thioxanthene‐hemicyanine (AS‐Cy‐1) and a 4‐nitrobenzene moiety, showed a 10‐fold ratiometric NIRF enhancement (I773/I733) and 2.4‐fold ratiometric PA enhancement (PA730/PA670) upon activation by a biomarker (nitroreductase, NTR) associated with tumor hypoxia. Moreover, the dual ratiometric NIRF/PA imaging accurately quantified the hypoxia extent with high sensitivity and high imaging depth in xenograft breast cancer models. More importantly, the 3D maximal intensity projection (MIP) PA images of the probe can precisely differentiate the highly heterogeneous oxygen distribution in solid tumor. Thus, this study provides a promising NIRF/PA scaffold that may be generalized for the dual ratiometric imaging of other disease‐relevant biomarkers. [ABSTRACT FROM AUTHOR]

Herein, we describe an energy balance strategy between fluorescence and photoacoustic effects by sulfur substitution to transform existing hemicyanine dyes (Cy) into optimized NIRF/PA dual ratiometric scaffolds. Based on this optimized scaffold, we reported the first dual‐ratio response of nitroreductase probe AS‐Cy‐NO2, which allows quantitative visualization of tumor hypoxia in vivo. AS‐Cy‐NO2, composed of a new NIRF/PA scaffold thioxanthene‐hemicyanine (AS‐Cy‐1) and a 4‐nitrobenzene moiety, showed a 10‐fold ratiometric NIRF enhancement (I773/I733) and 2.4‐fold ratiometric PA enhancement (PA730/PA670) upon activation by a biomarker (nitroreductase, NTR) associated with tumor hypoxia. Moreover, the dual ratiometric NIRF/PA imaging accurately quantified the hypoxia extent with high sensitivity and high imaging depth in xenograft breast cancer models. More importantly, the 3D maximal intensity projection (MIP) PA images of the probe can precisely differentiate the highly heterogeneous oxygen distribution in solid tumor. Thus, this study provides a promising NIRF/PA scaffold that may be generalized for the dual ratiometric imaging of other disease‐relevant biomarkers. [ABSTRACT FROM AUTHOR]

Treatment in combination with real-time monitoring of dynamic organelle changes is of great significance for evaluating therapeutic efficacy. However, it remains highly challenging to realize such specific treatment and monitoring in organelles. Herein, we developed one kind of red emissive two-photon carbon dots (TP-CDs) via an N doping strategy for nucleolus-targeted treatment combined with real-time monitoring of dynamic changes in the nucleolus. In the TP-CD system, N doping endows TP-CDs with intrinsic two-photon excitation, red emission at 605 nm, and singlet oxygen (1O 2) production under 638 nm laser irradiation. More importantly, N heterocycles induced by doping offers significant affinity for TP-CDs toward RNA to realize specific self-targeting toward nucleolus and fluorescence variation during the photodynamic therapy (PDT) via the cleaving of RNA chain by 1O 2 to dissociate TP-CDs@RNA complex. By combining 1O 2 production, fluorescent variation during the PDT process, long-wavelength excitation and emission characteristics, as well as specific self-targetability of nucleolus, TP-CDs can be considered as a kind of "smart" CDs to realize treatment in combination of real-time dynamic changes in nucleolus for the first time. [Display omitted] [ABSTRACT FROM AUTHOR]

The selection of suitable nanozymes with easy synthesis, tumor specificity, multifunction, and high therapeutics is meaningful for tumor therapy. Herein, a facile one‐step assembly approach was employed to successfully prepare a novel kind of natural polyphenol tannic acid (TA) hybrid with mixed valence vanadium oxide nanosheets (TA@VOx NSs). In this system, VOx is assembled with TA through metal–phenolic coordination interaction to both introduce superior peroxidase‐like activity and high near infrared (NIR) absorption owing to partial reduction of vanadium from V5+ to V4+. The presence of mixed valence vanadium oxide in TA@VOx NSs is proved to be the key for the catalytic reaction of hydrogen peroxide (H2O2) to.OH, and the corresponding catalytic mechanism of H2O2 by TA@VOx NSs is proposed. Benefitting from such peroxidase‐like activity of TA@VOx NSs, the overproduced H2O2 of the tumor microenvironment allows the realization of tumor‐specific chemodynamic therapy (CDT). As a valid supplement to CDT, the NIR absorption enables TA@VOx NSs to have NIR light‐mediated conversion ability for photothermal therapy (PTT) of cancers. Furthermore, in vitro and in vivo experiments confirmed that TA@VOx NSs can effectively inhibit the growth of tumors by synergistic CDT/PTT. These results offer a promising way to develop novel vanadium oxide‐based nanozymes for enhanced synergistic tumor‐specific treatment. [ABSTRACT FROM AUTHOR]

We describe the development of supercharged fluorescent protein modified water-soluble poly(N-phenylglycine) nanoparticles (SPNPG/ScGFP) as a novel nanotheranostic agent with highly effective cell penetration for image-guided photothermal cancer therapy. [ABSTRACT FROM AUTHOR]

Abstract: Indocyanine green (ICG) is an effective light absorber for laser‐mediated photodynamic therapy. However, applications of ICG are limited due to its rapid degradation and poor photostability in water. Herein, we report the development of a multifunctional nanoplatform by coating ICG on the surface of single‐walled carbon nanohorns (SWNHs) through π–π stacking, obtaining SWNH‐ICGs with high solubility and stability under physiological conditions. The SWNH‐ICGs could be used as a single nanoplatform to simultaneously produce satisfactory hyperthermia and reactive oxygen species under near‐infrared (NIR) laser irradiation. In addition, the SWNH‐ICGs not only improved the photostability of ICG in different media, but also protected it from light degradation. The SWNH‐ICGs exhibited highly efficient thermal/photoacoustic (PA) imaging‐guided photothermal therapy (PTT) and photodynamic therapy (PDT) effects, even under low‐power laser irradiation (0.3 W cm−2) in vitro. Combined PTT and PDT effectively killed triple‐negative breast cancer 4T1 cells, demonstrating a markedly improved and synergistic therapeutic effect compared to PTT or PDT alone. Furthermore, significant tumor growth inhibition as well as tumor cell death were observed following PTT/PDT at 808 nm laser irradiation, confirming the synergistic effects of SWNH‐ICGs over free ICG in vivo. This facile and simple methodology for thermal/PA imaging‐guided PTT/PDT suggests that SWNH‐ICGs may serve as an effective nanoplatform for cancer therapy. [ABSTRACT FROM AUTHOR]

It is of extreme importance to engineer the structural characteristics of carbon dots (CDs) to satisfy their practical applications in imaging and medical treatments. Here, Cu,N-doped CDs ( Cu,N -CDs) are a new class of near-infrared-(NIR) light-induced therapeutic agents that were prepared by a one-step hydrothermal method using EDTA·2Na and CuCl 2 . Specifically, Cu ΙΙ was located in the inner of Cu,N -CDs via N-Cu-N complexation, endowing NIR absorption for the production of heat and reactive oxygen species. The relationships between the hydrothermal temperature, NIR absorption, and intrinsic biological activity of the Cu,N -CDs were examined. The hydrothermal temperature significantly affected the latter two when the Cu content in the Cu,N -CDs was changed. The Cu,N -CDs at 180 °C were examined for cancer phototherapeutics in vitro and in vivo . The Cu,N -CDs markedly inhibited cancer via synergistic photothermal/photodynamic therapies. In addition, the Cu,N -CDs could also act as one kind of fluorescence cell-imaging agent and IR thermal imaging agent to visualize the in vitro and in vivo treatment process, respectively. Thus, the present study provides a promising new method to prepare CDs with NIR absorption feature for multifunctional cancer theranostic applications. [ABSTRACT FROM AUTHOR]

Wound is highly susceptible to bacterial infection, which can cause chronic wound and serial complications. However, timely treatment is hampered by the lack of real-time monitoring of wound status and effective therapeutic systems. Herein, in situ biosynthesis of functional conjugated polymer in artificial hydrogel was developed via the utilization of biological microenvironment to realize monitoring in real time of wound infection and inhibition of bacteria for the first time. Specially, an easily polymerizable aniline dimer derivative (N-(3-sulfopropyl) p-aminodiphenylamine, SPA) was artfully in situ polymerized into polySPA (PSPA) in calcium alginate hydrogel, which was initiated via the catalysis of hydrogen peroxide (H 2 O 2) overexpressed in infected wound to produce hydroxyl radical (•OH) by preloaded horseradish peroxidase (HRP). Benefitting from outstanding near infrared (NIR) absorption of PSPA, such polymerization can be ingeniously used for real-time monitoring of H 2 O 2 via naked-eye and photoacoustic signal, as well as NIR light-mediated photothermal inhibition of bacteria. Furthermore, combining the persistent chemodynamic activity of •OH, the in vivo experimental data proved that the wound healing rate was 99.03% on the 11th day after treatment. Therefore, the present work opens the way to manipulate in situ biosynthesis of functional conjugated polymer in artificial hydrogels for overcoming the issues on wound theranostics. [ABSTRACT FROM AUTHOR]

Herein, we describe an energy balance strategy between fluorescence and photoacoustic effects by sulfur substitution to transform existing hemicyanine dyes (Cy) into optimized NIRF/PA dual ratiometric scaffolds. Based on this optimized scaffold, we reported the first dual‐ratio response of nitroreductase probe AS‐Cy‐NO2, which allows quantitative visualization of tumor hypoxia in vivo. AS‐Cy‐NO2, composed of a new NIRF/PA scaffold thioxanthene‐hemicyanine (AS‐Cy‐1) and a 4‐nitrobenzene moiety, showed a 10‐fold ratiometric NIRF enhancement (I773/I733) and 2.4‐fold ratiometric PA enhancement (PA730/PA670) upon activation by a biomarker (nitroreductase, NTR) associated with tumor hypoxia. Moreover, the dual ratiometric NIRF/PA imaging accurately quantified the hypoxia extent with high sensitivity and high imaging depth in xenograft breast cancer models. More importantly, the 3D maximal intensity projection (MIP) PA images of the probe can precisely differentiate the highly heterogeneous oxygen distribution in solid tumor. Thus, this study provides a promising NIRF/PA scaffold that may be generalized for the dual ratiometric imaging of other disease‐relevant biomarkers. [ABSTRACT FROM AUTHOR]

Cover Feature: Natural Polyphenol-Vanadium Oxide Nanozymes for Synergistic Chemodynamic/Photothermal Therapy (Chem. Eur. J. 66/2020) Keywords: chemodynamic therapy; nanoenzymes; photothermal therapy; tumor microenvironments; vanadium oxide EN chemodynamic therapy nanoenzymes photothermal therapy tumor microenvironments vanadium oxide 15048 15048 1 11/28/20 20201126 NES 201126 B One-step assembly of tannic acid and metavanadate b led to the formation of a type of nanozyme comprising natural polyphenol-hybrided mixed valence vanadium oxide nanosheets (TA@VO SB I x i sb NSs). Chemodynamic therapy, nanoenzymes, photothermal therapy, tumor microenvironments, vanadium oxide. [Extracted from the article]

While applying computer simulations to study semiflexible polymers, it is a primary task to determine the persistence length that characterizes the chain stiffness. One frequently asked question concerns the relationship between persistence length and the bending constant of applied bending potential. In this paper, theoretical persistence lengths of polymers with two different bending potentials were analyzed and examined by using lattice Monte Carlo simulations. We found that the persistence length was consistent with theoretical predictions only in bond fluctuation model with cosine squared angle potential. The reason for this is that the theoretical persistence length is calculated according to a continuous bond angle, which is discrete in lattice simulations. In lattice simulations, the theoretical persistence length is larger than that in continuous simulations. [ABSTRACT FROM AUTHOR]

Abstract: Invited for the cover of this issue is the group of Xing‐Can Shen at the Guangxi Normal University. The image depicts how SWNH‐ICGs efficiently inhibit the growth of tumor cells under NIR light irradiation. Read the full text of the article at 10.1002/chem.201802611. [ABSTRACT FROM AUTHOR]