Abstract The rapid development and clinical trials of biodegradable nanoparticles (NPs) are heavily hindered by many factors, including poor drug loading, low drug concentration at disease sites, ...lack of active targeting function, etc . Herein, we developed a new smart and hype-responsive polyprodrug platform with five key elements ( i.e . chemically incorporated drug molecules in backbone, stimuli-responsive bond, hyper-fast chain-breakage ability, hydrophilic segment and targeting ligand). Using 10-hydroxycamptothecin (HCPT) as model drug, we designed and prepared an exemplified redox-responsive amphiphilic polyprodrug via polycondensation and “click” chemistry. This polymer is composed of a hydrophobic HCPT-based polyprodrug, a hydrophilic poly(ethylene oxide) (PEG) chain and a tumor-targeting RGD tail. Employing nanoprecipitation technique, small-sized NPs (<70 nm) can be obtained. The in vitro and in vivo results prove that this newly developed nanoplatform has the following unique characteristics: 1) high and constant drug loading (>36 wt.%), 2) excellent tumor-targeting performance, 3) hyper-fast redox-responsive drug release (around 70% accumulative release within 2 h), 4) long blood circulation and 5) significant inhibition of tumor growth without side effects.
With the aim to develop a facile strategy to prepare functional drug carriers to overcome multidrug resistance (MDR), we prepared heparin/protamine/calcium carbonate (HP/PS/CaCO3) hybrid nanovesicles ...with enhanced cell internalization, good serum stability, and pH sensitivity for drug delivery. All the functional components including protamine to improve the cell uptake, heparin to enhance the stability, and CaCO3 to improve drug loading and endow the system with pH sensitivity were introduced to the nanovesicles by self-assembly in an aqueous medium. An antitumor drug (doxorubicin, DOX) and a drug resistance inhibitor (tariquidar, TQR) were coloaded in the nanovesicles during self-assembly preparation of the nanovesicles. The drug loaded nanovesicles, which had a mean size less than 200 nm, exhibited a pH-sensitive drug release behavior. In vitro study was carried out in both nonresistant cells (HeLa and MCF-7) and drug-resistant cancer cells (MCF-7/ADR). Because of the enhanced intracellular and nuclear drug accumulation through effective inhibition of the P-gp efflux transporter, DOX/TQR coloaded nanovesicles showed significantly improved tumor cell inhibitory efficiency, especially for drug-resistant cells. These results suggest the self-assembled nanovesicles have promising applications in multidrug delivery to overcome drug resistance in tumor treatments.
With the increasing problem of antimicrobial drug resistance, the search for new antimicrobial agents has become a crucial task in the field of medicine. Antimicrobial peptides, as a class of ...naturally occurring antimicrobial agents, possess broad-spectrum antimicrobial activity and lower risk of resistance development. However, traditional screening methods for antimicrobial peptides are inefficient, necessitating the development of an efficient screening model. In this study, we aimed to develop an ensemble learning model for the identification of antimicrobial peptides, named E-CLEAP, based on the Multilayer Perceptron Classifier (MLP Classifier). By considering multiple features, including amino acid composition (AAC) and pseudo amino acid composition (PseAAC) of antimicrobial peptides, we aimed to improve the accuracy and generalization ability of the identification process. To validate the superiority of our model, we employed five-fold cross-validation and compared it with other commonly used methods for antimicrobial peptide identification. In the experimental results on an independent test set, E-CLEAP achieved accuracies of 97.33% and 84% for the AAC and PseAAC features, respectively. The results demonstrated that our model outperformed other methods in all evaluation metrics. The findings of this study highlight the potential of the E-CLEAP model in enhancing the efficiency and accuracy of antimicrobial peptide screening, which holds significant implications for drug development, disease treatment, and biotechnology advancement. Future research can further optimize the model by incorporating additional features and information, as well as validating its reliability on larger datasets and in real-world environments. The source code and all datasets are publicly available at https://github.com/Wangsicheng52/E-CLEAP.
Semitransparent organic photovoltaics (ST‐OPVs) have great potential for use in renewable energy technologies. In bulk‐heterojunction (BHJ) ST‐OPVs, a compromise is necessary between the visible ...light transmittance (VLT) and the power conversion efficiency (PCE). A sequential deposition (SD) strategy that involves individually depositing a polymer donor layer (D) and a small‐molecule acceptor layer (A) as the active layer is presented; where molecular diffusion occurring at the interfacial region results in a pseudo p–i–n structure. PBDB‐T‐2F(D)/Y6(A) ST‐OPVs are fabricated with different active layer thicknesses—at 115 nm, the SD (D:A/75:40 nm) and BHJ devices (D:A/1:1.2 w) provide the champion PCE of 12.91% (VLT of 14.5%) and 12.77% (VLT of 13.4%), respectively; at 85 nm, the SD (D:A/45:40 nm) and BHJ devices (D:A/1:1.2 w) provide a PCE of 12.22% (VLT of 22.2%) and 11.23% (VLT of 16.6%), respectively. This trend indicates SD devices have larger PCE and VLT values than the BHJ devices at a given active layer thickness, and the enhancements of PCE and VLT values by the SD structures against the BHJ structures become more pronounced as the active layer thickness reduced. The SD strategy provides a new approach for achieving ST‐OPVs with both high efficiency and high transparency.
In typical semitransparent organic photovoltaics (ST‐OPVs) that incorporate bulk heterojunction (BHJ) active layers, a compromise is made between the visible light transmittance (VLT) and power conversion efficiency (PCE). A new strategy with a sequential‐deposition (SD) active layer involving pseudo p–i–n structures provides ST‐OPVs with simultaneously higher PCE and VLT than that of the BHJ devices at the same layer thickness.
Carbon aerogels with 3D networks of interconnected nanometer‐sized particles exhibit fascinating physical properties and show great application potential. Efficient and sustainable methods are ...required to produce high‐performance carbon aerogels on a large scale to boost their practical applications. An economical and sustainable method is now developed for the synthesis of ultrathin carbon nanofiber (CNF) aerogels from the wood‐based nanofibrillated cellulose (NFC) aerogels via a catalytic pyrolysis process, which guarantees high carbon residual and well maintenance of the nanofibrous morphology during thermal decomposition of the NFC aerogels. The wood‐derived CNF aerogels exhibit excellent electrical conductivity, a large surface area, and potential as a binder‐free electrode material for supercapacitors. The results suggest great promise in developing new families of carbon aerogels based on the controlled pyrolysis of economical and sustainable nanostructured precursors.
Nano‐woodwork: An economical and sustainable method has now been developed for the synthesis of ultrathin carbon nanofiber (CNF) aerogels by engineering the thermal decomposition chemistry of nanofibrillated wood cellulose. This work suggests great promise in developing new families of carbon aerogels based on the controlled pyrolysis of sustainable nanostructured precursors.
Tumor cells form immune escape and subsequently obtain unlimited proliferation ability due to the abnormal immune surveillance mediated by immune checkpoints. Among this class of immune checkpoints, ...PD-1/PD-L1 was recognized as an anticancer drug target for many years, and so far, several monoclonal antibodies have achieved encouraging outcome in cancer treatment by targeting the PD-1/PD-L1 signaling pathway. Due to the inherent limitations of antibodies, the development of small molecule inhibitors based on PD-1/PD-L1 signaling pathway is gradually reviving in decades. In this review, we summarized a number of small molecule inhibitors based on three different therapeutic approaches interfering PD-1/PD-L1 signaling pathway: (1) blocking direct interaction between PD-1 and PD-L1; (2) inhibiting transcription and translation of PD-L1; and (3) promoting degradation of PD-L1 protein. The development of these small molecule inhibitors opens a new avenue for tumor immunotherapy based on PD-1/PD-L1 signaling pathway.
Superelastic carbon aerogels have been widely explored by graphitic carbons and soft carbons. These soft aerogels usually have delicate microstructures with good fatigue resistance but ultralow ...strength. Hard carbon aerogels show great advantages in mechanical strength and structural stability due to the sp3‐C‐induced turbostratic “house‐of‐cards” structure. However, it is still a challenge to fabricate superelastic hard carbon‐based aerogels. Through rational nanofibrous structural design, the traditional rigid phenolic resin can be converted into superelastic hard carbon aerogels. The hard carbon nanofibers and abundant welded junctions endow the hard carbon aerogels with robust and stable mechanical performance, including superelasticity, high strength, extremely fast recovery speed (860 mm s−1), low energy‐loss coefficient (<0.16), long cycle lifespan, and heat/cold‐endurance. These emerging hard carbon nanofiber aerogels hold a great promise in the application of piezoresistive stress sensors with high stability and wide detection range (50 kPa), as well as stretchable or bendable conductors.
A family of hard carbon aerogels with nanofibrous structure templated by various nanofibers is fabricated, displaying robust and stable mechanical performances, including high strength, extremely fast recovery speed (860 mm s−1), and ultralow energy loss coefficient (<0.16). After being compressed for 104 cycles (50% strain), they show only ≈2% plastic deformation and retain ≈93% stress.
Nanotheranostic agents (NTAs) that integrate diagnostic capabilities and therapeutic functions have great potential for personalized medicine, yet poor tumor specificity severely restricts further ...clinical applications of NTAs. Here, a pro‐NTA (precursor of nanotheranostic agent) activation strategy is reported for in situ NTA synthesis at tumor tissues to enhance the specificity of tumor therapy. This pro‐NTA, also called PBAM, is composed of an MIL‐100 (Fe)‐coated Prussian blue (PB) analogue (K2MnFe(CN)6) with negligible absorption in the near‐infrared region and spatial confinement of Mn2+ ions. In a mildly acidic tumor microenvironment (TME), PBAM can be specifically activated to synthesize the photothermal agent PB nanoparticles, with release of free Mn2+ ions due to the internal fast ion exchange, resulting in the “ON” state of both T1‐weighted magnetic resonance imaging and photoacoustic signals. In addition, the combined Mn2+‐mediated chemodynamic therapy in the TME and PB‐mediated photothermal therapy guarantee a more efficient therapeutic performance compared to monotherapy. In vivo data further show that the pro‐NTA activation strategy could selectively brighten solid tumors and detect invisible lymph node metastases with high specificity.
A metal–organic framework hybrid is designed as a precursor of a nanotheranostic agent (pro‐NTA) to selectively synthesize an NTA with the release of Mn2+ ions in tumor tissues. This pro‐NTA activation strategy provides multimodal diagnosis and tumor treatment with high specificity.
The development of highly active and stable electrocatalysts for ethanol electroxidation is of decisive importance to the successful commercialization of direct ethanol fuel cells. Despite great ...efforts invested over the past decade, their progress has been notably slower than expected. In this work, the facile solution synthesis of 2D PdAg alloy nanodendrites as a high‐performance electrocatalyst is reported for ethanol electroxidation. The reaction is carried out via the coreduction of Pd and Ag precursors in aqueous solution with the presence of octadecyltrimethylammonium chloride as the structural directing agent. Final products feature small thickness (5–7 nm) and random in‐plane branching with enlarged surface areas and abundant undercoordinated sites. They exhibit enhanced electrocatalytic activity (large specific current ≈2600 mA mgPd−1) and excellent operation stability (as revealed from both the cycling and chronoamperometric tests) for ethanol electroxidation. Control experiments show that the improvement comes from the combined electronic and structural effects.
2D PdAg alloy nanodendrites are prepared in solution with assistance from a cationic surfactant with a long alkyl chain. They feature small thickness and random in‐plane branching with enlarged surface areas and abundant undercoordinated sites. When evaluated as an electrocatalyst for the ethanol oxidation reaction, they demonstrate impressive electrocatalytic activity and stability superior to most other competitors.
By virtue of their extraordinarily high surface areas, ordered pore structures, various compositions, and rich functionality, metal–organic frameworks (MOFs) are of great interest in diverse fields ...such as gas separation, sensing, catalysis, energy, environment science, and biomedicine. However, the difficulty in processing MOF crystals and controlling the MOF superstructure is emerging as a critical issue in their application. Herein, it is reported that a robust template, i.e., nanofibrillated cellulose (NFC), can be used for the synthesis of MOF materials with 1D nanofiber morphology. NFC@MOF core–shell nanofibers with a uniform network structure and high aspect ratios can be prepared by use of this template. The small crystal size, flexibility, and good dispersity of the NFC@MOF nanofibers make it convenient for the macroscale assembly and solution processing of MOF materials. A proof‐of‐concept study is demonstrated wherein freestanding MOF nanofiber membranes represent good performance in applications of water treatment and heterogeneous catalysis reaction. This general synthesis and solution‐processing strategy may herald a new era in promoting the industrial application of MOFs.
A robust template, i.e., nanofibrillated cellulose, can be employed for the synthesis of high‐quality metal–organic frameworks (MOF) materials with 1D nanofiber morphology. The good solution dispersibility and membrane formability of MOF nanofibers surpass traditional MOF powder materials, which facilitates their processing and application.
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