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Production of 2,6-dihydroxybenzoic acid (2,6-DHBA) via enzymatic carboxylation of resorcinol by decarboxylases is of great promising but shows depressed equilibrium conversion. In this study, 2,3-dihydroxybenzoic acid decarboxylase from Aspergillus oryzae (2,3-DHBD_Ao) pushing the conversion towards carboxylation for efficient 2,6-DHBA biosynthesis was achieved. Meanwhile, a novel amino-modified and lignin-doped cellulose nanocrystal aerogel (A-LCNCA) with high specific surface area and prominent CO 2 capture was prepared for 2,3-DHBD_Ao immobilization. 2,3-DHBD_Ao@A-LCNC contributed a further enhanced conversion of carboxylation with the maximal conversion of 76.2 %, which was correlated to both the activity of 2,3-DHBD_Ao and the high CO 2 loading capacity of A-LCNCA. Moreover, 2,3-DHBD_Ao@A-LCNC exhibited superior performances in a wider range of temperature and higher concentrations of substrate, with a prolonged storage period longer than 30 days. After seven cycles reuse, 2,3-DHBD_Ao@A-LCNCA could retain 85.3 % of its original activity. These results suggest a considerable potential of 2,3-DHBD_Ao@A-LCNCA in the selective biosynthesis of 2,6-DHBA., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Lung cancer remains one of the leading causes of death in humans. Gefitinib is an inhibitor of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) commonly used to suppress tumour growth. However, constantly use of gefitinib results in drug-resistance, reduced efficacy and undesired side effects. To circumvent these drawbacks, targeted and photothermal therapies have emerged as effective strategies. Herein, we are first to adopt a black phosphorus (BP) nanoparticle-based novel delivering strategy by combining gefitinib and cancer cytomembrane to treat non-small cell lung cancer (NSCLC). In these gefitinib-containing nano-carriers, cyanine 5 (Cy5) biotin-labelled BP was incorporated with cancer membrane and then consists of a nanomaterial (BPGM), which enabled to deliver gefitinib to the tumours effectively. The combination of BPGM showed reinforcing effects to suppress NSCLC cells and xenograft tumours without apparent adverse effects both in vitro and in vivo . BPGM facilitated the delivery of gefitinib to tumour tissue and extended its retention time within tumours. These studies thus suggest that BP may serve as novel delivery strategy for lung cancer.

A multifunctional nanodrug (Tf-DHA-ASO-MnO 2 ) based on manganese dioxide nanosheets was constructed by triple-dressing with transferrin, dihydroartemisinin, and antisense oligonucleotide sequences. Tf-DHA-ASO-MnO 2 shows an effective targeted cancer therapy ability through the ferroptosis caused by the production of excessive lipid peroxides resulting from the combined effect of glutathione exhaustion, reactive oxygen species generation and down-regulation of glutathione peroxidase 4.

The inability of drugs to cross the blood-brain barrier (BBB) makes it difficult to treat diseases in the central nervous system. It is known that peptides with or without specific receptors on the BBB showed different or even controversial neuron targeting capability in different reports. So, it is necessary to clarify how these peptides work as targeting molecules in the central nervous system. Herein, we evaluate and compare the performance of 6 kinds of peptides with (T7, D-T7, and GSH) or without (TGN, CGN, and TAT) BBB-specific receptors by conjugating these peptides on lipids to serve as a shell to encapsulate a core of PLGA and lamotrigine to form nanoparticles for targeted epilepsy therapy. In vitro assay shows that the TAT-modified nanoparticles show the highest internalization efficacy in the BBB model cell line bEnd·3 cells and hippocampal neurons. By contrast, experiments in mice show that the D-T7-modified nanoparticles have the highest brain targeting and epilepsy therapeutic efficiency. Thus, our experiments uncover the different performances of the 6 peptides at different levels ( in vitro and in vivo ), which is insightful for developing novel delivery systems for treating diseases in the central nervous system.

The potential toxicity of nanoplastics on plants has previously been illustrated, but whether nanoplastics could cause neurotoxicity, especially to higher animals, remains unclear. We now demonstrate that nanoplastics can be deposited in the brain via nasal inhalation, triggering neuron toxicity and altering the animal behavior. Polystyrene nanoparticles (PS-NPs) of PS-COOH and PS-NH 2 are used as models for nanoplastics. We designed a microfluidic chip to evaluate the PS-NPs with different concentrations, surface ligands, and sizes to interact with neurons. Smaller PS-NPs can induce more cellular uptake than larger PS-NPs. PS-NPs with a size of 80 nm can reach and deposit in the brain of mice via aerosol inhalation. Mice inhaling PS-NPs exhibit fewer activities in comparison to those inhaling water droplets. An obvious neurotoxicity of the nanoplastics could be observed from the results of the inhibition of AChE activities. Our results show the potential significance of the physiochemical properties of organic nanoplastics on depositing in mammalian brains by nasal inhalation.

Transport ions into cells through nanocarrier to achieve ion-interference therapy provides new inspiration for cancer treatment. In this work, a pH-targeted and NIR-responsive NaCl-nanocarrier is prepared using surfactant Vitamin E-O(EG 2 -Glu) and modified with polydopamine (PDA) and pH-sensitive zwitterionic chitosan (ZWC). The NaCl-nanocarrier is decorated with NH 4 HCO 3 and IR-780 to introduce near-infrared (NIR)-responsive performance and imaging. Once the NaCl-nanocarrier is exposed to NIR laser, the temperature rises rapidly because of the excellent photothermal conversion ability of PDA, then NH 4 HCO 3 is decomposed into NH 3 and CO 2 , which burst the nanocarrier, resulting in Cl - and Na + "bomb-like" release. This pH-targeted nanocarrier accumulates more at tumor site and when irradiating the site with NIR light, the temperature rises and excessive Cl - and Na + are released to destroy the ion homeostasis and inhibit tumor growth effectively. Through this strategy, the unique combination of ion interference therapy and photothermal therapy is achieved., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Three series of thermo- and/or pH-responsive polymer-grafted SiO2 nanoparticles, SiO2-graft-poly(oligo(ethylene glycol) methacrylate) (SiO2-g-POEGMA), SiO2-graft-poly(acrylic acid) (SiO2-g-PAA) and SiO2-graft-poly(oligo(ethylene glycol) methacrylate-state-acrylic acid (SiO2-g-P(OEGMA-stat-AA)), were prepared by grafting POEGMA and/or PAA onto the surface of silica nanoparticles through the surface-initiated atom transfer radical polymerization (SI-ATRP). The lower critical solution temperature (LCST) of SiO2-g-POEGMA (MOEGMA = 300 g/mol) was found to be 64 °C. For SiO2-g-PAA nanoparticles, at the pH range from 8 to 12, the hydrodynamic diameter of the nanoparticles increases with increasing pH, and the zeta potential of SiO2-g-PAA nanoparticles is negatively charged and decreases with increasing pH. Owing to the thermo- and pH-responsive, the hydrodynamic diameters of SiO2-g-P(OEGMA-stat-AA) nanoparticles increase with the increasing pH, and the LCSTs of those nanoparticles increase with the increase of POEGMA content. [ABSTRACT FROM AUTHOR]

BiVO 4 film coupled with resorcinol–formaldehyde resin (RFS) nanoparticles to form BiVO 4 /RFS heterojunction film as photoanode for solar water oxidation. The conduction and valence band potential of RFS nanoparticles were lower than those of BiVO 4 , and the surface holes and electrons could be directionally transferred to RFS nanoparticles and BiVO4 film, respectively. [Display omitted] • BiVO 4 /RFS film photoanodes were prepared by coupling BiVO 4 films with resorcinol–formaldehyde resin nanoparticles for solar water oxidation. • The light harvesting and electrochemical properties of the optimal BiVO 4 /RFS film was close to the BiVO 4 film. • Better water oxidation activity, kinetics and stability were observed on the BiVO 4 /RFS film photoanode. • The conduction and valence band potential of RFS nanoparticles were lower than those of BiVO 4 , and their surface holes and electrons could be directionally transferred to RFS nanoparticles and BiVO 4 film, respectively. The poor properties of carrier separation and transfer on BiVO 4 surface are two major bottlenecks for nanostructured BiVO 4 photoanodes during solar water oxidation. Herein, BiVO 4 /resorcinol–formaldehyde resin (BiVO 4 /RFS) heterojunction films were prepared by coupling resorcinol–formaldehyde resin (RFS) nanoparticles on BiVO 4 films' surface, and investigated as photoanodes for solar water oxidation. The light harvesting and electrochemical properties of the resultant BiVO 4 /RFS film was close to the BiVO 4 film, but its carrier radiative recombination was weakened significantly. Relative to the BiVO 4 film photoanode, better water oxidation activity, kinetics and stability were observed on the BiVO 4 /RFS film photoanode. The conduction and valence band potential of RFS nanoparticles were discovered to be lower than those of BiVO 4 , and the surface photogenerated holes and electrons could be directionally transferred to RFS nanoparticles and BiVO 4 film, respectively. The higher solar water oxidation performance on the BiVO 4 /RFS photoanode was mainly originated from the separation and transfer of surface carrier through the BiVO 4 /RFS coupling interfaces under AM 1.5G irradiation. The present work could provide inspiration in the design and development of similar heterojunction materials for solar water splitting. [ABSTRACT FROM AUTHOR]

• Ag nanoparticles are anchored onto CuS sub-micron flowers to form composites. • The CuS@Ag electrodes exhibit enhanced charge storage property. • The decoration of Ag nanoparticles increases the electrical conductivity. • The generated electric field at the CuS/Ag interface accelerates the charge transfer. [Display omitted] In this reported work, Ag nanoparticles (NPs) decorated CuS sub-micron flowers are synthesized using a facile, solvothermal reaction coupled with a silver mirror reaction. The experimental results and theoretical calculations reveal that decorating the CuS with Ag NPs increases its intrinsic electrical conductivity and generates an electric field at the interface between Ag and CuS. These effects promote the efficient utilization of active materials and accelerate the interface charge transfer and electrochemical reaction kinetics. Consequently, the maximum specific capacity of the prepared CuS@Ag electrodes is found to be as high as 702 C g−1 at 2 A g−1, which is about 5 times greater than the pure CuS electrode. In addition, the capacity value is 400 C g−1 at 20 A g−1 and it exhibits 93% retention of the initial capacity after 5000 cycles at 10 A g−1. Moreover, a hybrid supercapacitor (HSC) device is assembled employing the CuS@Ag electrode as the positive electrode, which delivers an energy density of 51.1 Wh kg−1 at a power density of 798 W kg−1. These results demonstrate the promising potential of the fabricated CuS@Ag composites for further application in HSCs. [ABSTRACT FROM AUTHOR]