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Naringin, a natural product, can be used as a therapeutic agent due to its low systemic toxicity and negligible adverse effect. However, due to its hydrophobic nature and thereby low solubility, high-dose treatment is required when used for human therapy. Herein, we demonstrate the employment of a metal-organic framework (MOF) as a nontoxic loading carrier to encapsulate naringin, and the afforded nairngin@MOF composite can serve as a multifunctional bioplatform capable of treating Gram-positive bacteria and certain cancers by slowly and progressively releasing the encapsulated naringin as well as improving and modulating immune system functions through synergy between naringin and the MOF.

Triple‑negative breast cancer (TNBC) is a highly heterogeneous and aggressive malignancy. Due to the absence of estrogen receptors and progesterone receptors and the lack of overexpression of human epidermal growth factor receptor 2, TNBC responds poorly to endocrine and targeted therapies. As a neoadjuvant therapy, chemotherapy is usually the only option for TNBC; however, chemotherapy may induce tumor resistance. The emergence of immunotherapy as an adjuvant therapy is expected to make up for the deficiency of chemotherapy. Most of the research on immunotherapies has been performed on advanced metastatic TNBC, which has provided significant clinical benefits. In the present review, possible immunotherapy targets and ongoing immunotherapy strategies were discussed. In addition, progress in research on immune checkpoint inhibitors in early TNBC was outlined.

We report a correlation between the structural phase transition of CsPbX3 (X = Cl, Br, I) nanocrystals (NCs) and their temperature-dependent steady-state photoluminescence (PL) and time-resolved PL (TRPL). In contrast to CsPbBr3 and CsPbI3 NCs which exhibited a continuous blue-shift in their band gap with increasing temperature, the CsPbCl3 exhibited a blue shift until ∼193 K, followed by a red shift until room temperature. We attribute this change from a blue to a red shift to a structural phase transition in CsPbCl3, which also manifested in the temperature dependent TRPL. This pronounced phase transition in CsPbCl3 NCs is probably due to the condensation of its vibrational modes at low temperature, and the presence of the weak quantum confinement effect. Notably, the exciton recombination lifetimes showed a similar reverse trend due to the phase transition in CsPbCl3, which has not been reported previously.

Tuning catalytic centers in heterogeneous catalyst, both in a chemical and a spatial manner, is a powerful approach to improve the stability and the efficiency of catalysts. While the chemical aspects are largely understood, the spatial interactions around active sites, comprised of non-covalent interactions, are difficult to maintain and challenging to study. Herein, the unique properties of covalent organic frameworks (COFs) are utilized to establish an ideal reaction environment for the hydrolysis of cellobiose and other common disaccharides in mild, metal-free, and neutral aqueous conditions. The chosen COF, HCl-PSA-IM-COF-OMe ("HCl" for hydrochloric acid, "PSA" for propyl sulfonic acid, "IM" for imidazole, and "OMe" for methoxy), is modified to be ultra-stable in aqueous conditions and possesses sulfonic acid groups for general acid catalysis and for enhanced hydrogen bonding with reactants as well as intraporous chloride anions for oxocarbenium intermediate stabilization. In addition, the system also relies on the differences in adsorptive binding behavior, K

We report a correlation between the structural phase transition of CsPbX(3) (X=Cl, Br, I) nanocrystals (NCs) and their temperature dependent steady-state photoluminescence (PL) and time-resolved PL (TRPL). In constrast to CsPbBr(3) and CsPbI(3) NCs which exhibited a continuous blue shift in their bandgap with increasing temperature, the CsPbCl(3) exhibited a blue shift until ~193 K, followed by a red shift until room temperature. We attribute this change from a blue to a red shift to a structural phase transtion in CsPbCl(3), which also manifested in the temperature dependent TRPL. Notably, the exciton recombination lifetimes showed a similar reverse trend due to the phase transition in CsPbCl(3), which has not been reported previously.

Albeit metal-organic framework (MOF) composites have been extensively explored, reducing the size and dimensions of various contents within the composition, to the nanoscale regime, has recently presented unique opportunities for enhanced properties with the formation of MOF-based nanocomposites. Many distinctive strategies have been used to fabricate these nanocomposites such as through the introduction of nanoparticles (NPs) into a MOF precursor solution or vice versa to achieve a core-shell or heterostructure configuration. As such, MOF-based nanocomposites offer seemingly limitless possibilities and promising solutions for the vast range of applications across biomedical disciplines especially for improving in vivo implementation. In this review, we focus on the recent development of MOF-based nanocomposites, outline their classification according to the type of integrations (NPs, coating materials, and different MOF-derived nanocomposites), and direct special attention towards the various approaches and strategies employed to construct these nanocomposites for their prospective utilization in biomedical applications including biomimetic enzymes and photo, chemo, sonodynamic, starvation and hyperthermia therapies. Lastly, our work aims to highlight the exciting potential as well as the challenges of MOF-based nanocomposites to help guide future research as well as to contribute to the progress of MOF-based nanotechnology in biomedicine.

Two imidazolium-based cationic polymeric nanotraps based on tetraphenylmethane building blocks (CPN-tpm) with different counterions were rationally designed and constructed for the efficient removal of Cr2O72- from wastewater. The influence of counterions on Cr2O72- adsorption performance was studied. With better wettability (contact angle as 28.61°), CPN-tpm-Cl exhibited a higher uptake capacity of 366 mg g−1 for Cr2O72- capture and a faster ion exchange kinetic process in 20 min. While CPN-tpm-Br with a contact angle of 83.16° showed a lower maximum capacity of 324 mg g−1. In addition, CPN-tpm-Cl can work in a wide pH range from 2 to 10 and possess excellent selectivity (such as Cl-, NO3- and SO42-) as well as good reusability for 5 times. Such excellent performances indicated that CPN-tpm-Cl is a promising candidate for the Cr2O72- capture application. Our work not only contributes cationic polymeric nanotraps as a promising candidate for Cr2O72- removal, but also suggests a new approach to develop new type of adsorbents for wastewater treatment.

Novel Fe-BDC/Fe-2MI heterojunction (H2BDC: terephthalic acid, 2MI: 2-methylimidazole) was prepared via a one-pot solvothermal method. Herein, mixed ligands (H2BDC and 2MI) was applied to form complex with Fe(III). Interestingly, the presence of 2MI can regulate the structure of Fe-BDC. Spindle-like MIL-88B(Fe) was observed in Fe-BDC/Fe-2MI composite, while MIL-53(Fe) was identified in naked Fe-BDC. By employing photoelectrochemical characterizations, Fe-BDC/Fe-2MI was optimized at an initial molar ratio of 1:0.5:10 for Fe(III):H2BDC:2MI, which exhibited the highest photocurrent response, lowest charge transfer resistance, and fastest surface reaction kinetics as compared to the individual Fe-BDC and Fe-2MI. Due to the formation of the heterojunction which lead to beneficial photoelectrochemical properties, the as-prepared samples exhibited boosted photocatalytic activity for Cr(VI) reduction. The calculated pseudo-first-order rate constant (k) was 0.046 min−1 for Fe-BDC/Fe-2MI, which was 15.3 and 6.6 times that of Fe-BDC (0.003 min−1) and Fe-2MI (0.007 min−1), respectively. Moreover, the optimized Fe-BDC/Fe-2MI demonstrated superior performance with negligible loss in activity after 4 cyclic runs.

In this work, by combining the superiority of polyoxometalates (POMs) and catalytic single-metal site Co of metalloporphyrin, a series of mixed-valence POM-based metal-organic frameworks (MOFs) composites is synthesized by a post-modification method. The electron-transfer property of POM@PCN-222(Co) composite is significantly enhanced owing to the directional electron-transfer from POM to single-metal site Co in PCN-222(Co). In particular, H-POM@PCN-222(Co) gives a high Faradaic efficiency of 96.2% for electroreduction of CO2 into CO and good stability over 10 h. DFT calculations confirm that the directional electron transfer, which accelerates the multi-electron transfer from the electrode to active single-metal site Co, enriches the electron density of the Co center, and ultimately reduces the energy of the rate-determining step, thus increasing the catalytic activity of CO2 reduction reaction (CO2 RR). This work therefore suggests some new insight for the design of efficient electrocatalysts for CO2 RR.

CeO2, one of most attractive rare earth oxides, that displays outstanding properties such as excellent catalytic activity, marked chemical/thermal stability and the ability for the formation/diffusion of oxygen vacancies, is widely used as the support for noble metal catalysts to improve the conversion efficiencies of catalytic reaction. In the past several decades, noble metal/ceria-based composites have been extensively employed in CO oxidation, water gas shift reaction, NO x reduction and solid oxide fuel cell, suggesting their important roles in green energy and environmental remediation. Normally, the complicated interaction between CeO2 and noble metals has great impact not only on the conversion rates of catalytic reactions, but also on the stability, activity and selectivity of the catalysts. This review focuses on the structures of the noble metal/ceria-based composition, including the conventional structure and novel structure. Based on novel structure, such as core-shell, yolk-shell, core-sheath, lamellar structure, the interaction between noble and ceria nanomaterials and the influence of the catalytic ability on this kind of interaction were all summarized. Whats more, the different structure features and synthetic methods of the catalyst, the application of the catalytic characteristic and the influence of the catalytic ability on composite structure were also systematic discussed. The researches in noble metal/ceria-based compositions hold great promise in the synthesis of different structured catalysts with abilities to manipulate catalytic reactions in more economic and efficient ways.

Ceria has emerged as a fascinating and lucrative material in bio-application, for instance, disease treatment, bioimaging and drug delivery due to its abilities of transforming oxidation states between Ce4+ and Ce3+ and scavenging free radicals, which can produce biological effect, such as being potentially antioxidant towards reactive oxygen species. Recently, many studies about one dimension (1D) CeO2 nanomaterials have received much attention because of the unique properties of their length and aspect ratio. We highlight here current research activities focused on the bio-application of 1D ceria nanomaterials. The synthesis methods of 1D cerium oxide nanomaterials were introduced. Several synthesis routes, including template, hydrothermal, sonochemical and other methods, were then discussed with examples developed by recent research. The differences among these methods were also analyzed. This review provides a comprehensive introduction to the synthesis of 1D ceria, its potential applications in biological fields and perspectives on this exciting realm.

Rare-earth doped titania single-crystalline hollow nanoparticles of 20 nm are constructed via a simple sol-gel process. Amphiphilic ABA tri-block copolymers played a key role in assisting the formation of hollow structure, for which a hollow nanostructure growth mechanism is proposed. By introducing rare earth into the synthesis process, the as-prepared nanoparticles exhibit near-infrared light absorption properties. Photo-decomposition efficiency of Orange II azo dye can be successfully evaluated when using Yb3+-doped TiO2 hollow nanoparticles as photocatalysts; it is more than two times higher than the pure TiO2 hollow nanoparticles. The hollow nanostructured Yb3+-doped TiO2 samples are exploited as photoanodes in N719-sensitized solar cells and prove able to improve the photoelectric conversion efficiency by measuring the solar cell parameters of dye-sensitized solar cells (DSSCs) under simulative sunlight.