Carbon nanotubes (CNTs) and their derivatives have emerged as a series of efficient biocatalysts to mimic the function of natural enzymes in recent years. However, the unsatisfiable enzymatic efficiency usually limits their practical usage ranging from materials science to biotechnology. Here, for the first time, we present the synthesis of several oxygenated-group-enriched carbon nanotubes (o-CNTs) via a facile but green approach, as well as their usage as high-performance peroxidase mimics for biocatalytic reaction. Exhaustive characterizations of the enzymatic activity of o-CNTs have been provided by exploring the accurate effect of various oxygenated groups on their surface including carbonyl, carboxyl, and hydroxyl groups. Because of the "competitive inhibition" effect among all of these oxygenated groups, the catalytic efficiency of o-CNTs is significantly enhanced by weakening the presence of noncatalytic sites. Furthermore, the admirable enzymatic activity of these o-CNTs has been successfully applied in the treatment of bacterial infections, and the results of both in vitro and in vivo nanozyme-mediated bacterial clearance clearly demonstrate the feasibility of o-CNTs as robust peroxidase mimics to effectively decrease the bacterial viability under physiological conditions. We believe that the present study will not only facilitate the construction of novel efficient nanozymes by rationally adjusting the degree of the "competitive inhibition" effect, but also broaden the biological usage of o-CNT-based nanomaterials via their satisfactory enzymatic activity.

A novel dynamic network was successfully prepared via self-complementary quadruple hydrogen bonding through Upy-telechelic poly(tetremethylene ether) glycol (PTMEG) and four-arm star-shaped poly(ε-caprolactone) ((4)PCL) precursors. The structure and the dynamic feature were identified by FT-IR and (1)H NMR. The differential scanning calorimetry (DSC) analysis indicated that the crystalline PCL and PTMEG segments show a separated melting peak, and the aggregation of Upy dimer was also observed. The dynamic mechanical analyzer (DMA) test reveals that the storage modulus of the network drops evidently across the thermal transition. These characteristics of the network ensure that it exhibits a triple-shape effect, and the composition of the network influences the performance of shape memory effect. The variation of the fixing ratio of the network in each deformation step is quite according to the crystallinity of the dominant segment. The reversibility of the quadruple hydrogen bonding between Upy dimer endues the network with self-healing capacity, and the damage and healing test of the network revealed that increasing the content of the PTMEG segment will be of benefit to self-healing performance.

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Recently, photooxygenation of amyloid β (Aβ) has emerged as an effective way to inhibit Aβ aggregation in Alzheimer's disease (AD) treatment. However, their further application has been highly obstructed by self‐aggregation, no metal chelating ability, and poor protein‐enrichment capacity. Herein, porphyrinic metal–organic frameworks (PMOFs) are utilized as a superior CuII chelating and photooxidation agent for inhibiting Aβ aggregation. We selected only four classical kinds of POMFs (Zr–MOF, Al–MOF, Ni–MOF, Hf–MOF) for further investigation in our study, which are stable in physiological conditions and exhibit excellent biocompatibility. Among them, Hf–MOF was the most efficient Aβ photooxidant. A possible explanation about the difference in capacity of 1O2 generation of these four PMOFs has been provided according to the experimental results and DFT calculations. Furthermore, Hf–MOFs are modified with Aβ‐targeting peptide, LPFFD. This can not only enhance Hf–MOFs targeting cellular Aβ to decrease Aβ‐induced cytotoxicity, but also improve Aβ photooxidation in the complicated living environment. More intriguingly, in vivo studies indicate that the well‐designed LPFFD modified Hf–MOFs can decrease Aβ‐induced neurotoxicity and extend the longevity of the commonly used transgenic AD model Caenorhabditis elegans CL2006. Our work may open a new avenue for using MOFs as neurotoxic‐metal‐chelating and photo‐therapeutic agents for AD treatment.

Nanoscale porphyrinic metal–organic frameworks (NMOFs) have emerged as promising therapeutic platforms for the photodynamic therapy (PDT) of cancer in recent years. However, the relatively large sizes of current NMOFs ranging from tens to hundreds of nanometers usually lead to inefficient body clearance and unsatisfactory PDT effect, thus amplifying their long-term toxicity and restricting their further usage. To overcome these shortcomings, herein, ultrasmall porphyrinic metal–organic framework nanodots (MOF QDs) prepared from NMOFs are rationally synthesized via a facile method and used as renal-clearable nanoagents for the enhanced PDT of cancer. Compared with the precursor NMOFs, our well-prepared MOF QDs can generate 2-fold effective toxic reactive oxygen species (ROS) upon the same light irradiation and greatly decrease the inefficacy of PDT caused by the inefficient use of ROS generated from the interior of NMOFs. Meanwhile, the IC50 value of ultrasmall MOF QDs is nearly one-third that of NMOFs, and in vivo results demonstrate that our MOF QDs exhibit better PDT efficacy than NMOFs under the same treatment owing to their overcoming the limited ROS diffusion distance. Significantly, these ultrasmall MOF QDs show efficient tumor accumulation and rapid renal clearance in vivo, indicating their potential in biomedical utility. Last but not least, comprehensive investigations of long-term toxicity of these MOF QDs well demonstrate their overall safety. Therefore, this study will offer valuable insight into the development of safe and high-performance PDT nanoplatforms for further clinical translation.

The inhibition of amyloid‐β (Aβ) aggregation by photo‐oxygenation has become an effective way of treating Alzheimer's disease (AD). New near‐infrared (NIR) activated treatment agents, which not only possess high photo‐oxygenation efficiency, but also show low biotoxicity, are urgently needed. Herein, for the first time, it is demonstrated that NIR activated black phosphorus (BP) could serve as an effective nontoxic photo‐oxidant for amyloid‑β peptide in vitro and in vivo. The nanoplatform BP@BTA (BTA: one of thioflavin‐T derivatives) possesses high affinity to the Aβ peptide due to specific amyloid selectivity of BTA. Importantly, under NIR light, BP@BTA can significantly generate a high quantum yield of singlet oxygen (1O2) to oxygenate Aβ, thereby resulting in inhibiting the aggregation and attenuating Aβ‐induced cytotoxicity. In addition, BP could finally degrade into nontoxic phosphate, which guarantees the biosafety. Using transgenic Caenorhabditis elegans CL2006 as AD model, the results demonstrate that the 1O2‐generation system could dramatically promote life‐span extension of CL2006 strain by decreasing the neurotoxicity of Aβ.

Phototherapyh as emerged as ap owerful approach for interrupting b-amyloid (Ab)s elf-assembly.H owever, deeper tissue penetration and safer photosensitizers are urgent to be exploited for avoiding damaging nearby normal tissues and improving therapeutic effectiveness.Ahydrogen-bonded organic framework (HOF)-based NIR-II photooxygenation catalyst is presented here to settle the abovementioned challenges.B ye ncapsulating the pyridinium hemicyanine dye DSM with alarge two-photon absorption (TPA) cross-section

Accumulated Cu in amyloid-β plaques can effectively catalyze the azide–alkyne cycloaddition reaction for fluorophore activation and drug synthesis. Our work may provide new insight intoin situdrug synthesis for neurodegenerative diseases.