Latest ArticlesIn recent years, biopharmaceuticals have witnessed remarkable advancements, transforming the landscape of therapeutic interventions. Biopharmaceuticals encompassing therapeutics generated through cutting-edge biotechnological methods have shown promising therapeutic outcomes. However, their clinical success hinges significantly on overcoming drug delivery challenges related to stability, intracellular delivery, immunogenicity, and pharmacokinetic properties. Herein, we provide an overview of various marketed macromolecules, including nucleic acids, and immunotherapeutic agents such as cytokines and monoclonal antibodies, as well as other therapeutic peptides/proteins like enzymes, hormones, and coagulation factors. Our primary focus is on elucidating the delivery challenges associated with these macromolecules and highlighting the pivotal role played by drug delivery platforms in the development of currently marketed products, offering valuable insights for both scientific research and the pharmaceutical industry.
Atomically dispersed Cu-based single-metal-site catalysts (Cu-N-C) have emerged as a frontier for electrocatalytic oxygen reduction reactions (ORR) because they can effectively optimize the d-band center of the Cu active site and provide appropriate adsorption/desorption energy for oxygen-containing intermediates. Metal-organic frameworks (MOFs) show excellent prospects in many fields because of their structural regularity and designability, but their direct use for electrocatalysis has been rarely reported due to the low intrinsic conductivity. Here, a MOF material (Cu-TCNQ) with highly regular single-atom copper active centers was successfully prepared using a solution chemical reaction method. Subsequently, Cu-TCNQ and graphene oxide (GO) were directly self-assembled to form a Cu-TCNQ/GO composite, which improved the conductivity of the catalyst while maintained the atomically precise controllability. The resistivity of the Cu-TCNQ/GO decreased by three orders of magnitude (1663.6–2.7 W/cm) compared with pure Cu-TCNQ. The half-wave potential was as high as 0.92 V in 0.1 mol/L KOH, even better than that of commercial 20% Pt/C. In alkaline polymer electrolyte fuel cells (APEFCs), the open-circuit voltage and power density of Cu-TCNQ/GO electrode reached 0.95 V and 320 mW/cm2, respectively, which suggests that Cu-TCNQ/GO has a good potential for application as a cathode ORR catalyst.
A visible light-promoted fast photochemical Wolff rearrangement was developed toward synthesis of α-substituted amides in continuous flow with the use of a photochemical oscillatory flow reactor (POFR). The control experiment indicates that a fast process of the Wolff rearrangement (<40 s) is involved. Notably, this protocol does not require excess use of any reactants, and the resulting α-substituted amides could be isolated by recrystallization in good to excellent yields.
Wearable flexible sensor devices have the characteristics of lightweight and miniaturization. Currently, power supply and detection components limit the portability of wearable flexible sensor devices. Meanwhile, conventional liquid electrolytes are unsuitable for the integration of sensing devices. To address these constraints, wearable biofuel cells and flexible electrochromic displays have been introduced, which can improve integration with other devices, safety, and color-coded display data. Meanwhile, electrode chips prepared through screen printing technology can further improve portability. In this work, a wearable sensor device with screen-printed chips was constructed and used for non-invasive detection of glucose. Agarose gel electrolytes doped with PDA-CNTs were prepared, and the mechanical strength and moisture retention were significantly improved compared with traditional gel electrolytes. Glucose in interstitial fluid was non-invasive extracted to the skin surface using reverse iontophoresis. As a biofuel for wearable biofuel cells, glucose drives self-powered sensor and electrochromic display to produce color change, allowing for visually measurement of glucose levels in body fluids. Accurate detection results can be visualized by reading the RGB value with a cell phone.
The considerable hazard posed by periprosthetic joint infections underlines the urgent need for the rapid advancement of in-situ drug delivery systems within joint materials. However, the pursuit of sustained antibacterial efficacy remains a formidable challenge. In this context, we proposed a novel strategy that leverages swelling and erosion mechanisms to facilitate drug release of drug-loaded ultrahigh molecular weight polyethylene (UHMWPE), thereby ensuring its long-lasting antibacterial performance. Polyethylene oxide (PEO), a hydrophilic polymer with fast hydrating ability and high swelling capacity, was incorporated in UHMWPE alongside the antibacterial tea polyphenol (epigallocatechin gallate, EGCG as representative). The swelling of PEO enhanced water infiltration into the matrix, while the erosion of PEO balanced the release of the encapsulated EGCG, resulting in a steady release. The behavior was supported by the EGCG release profiles and the corresponding fitted release kinetic models. As demonstrated by segmented antibacterial assessments, the antibacterial efficiency was enhanced 2 to 3 times in the PEO/EGCG/UHMWPE composite compared to that of EGCG/UHMWPE. Additionally, the PEO/EGCG/UHMWPE composite exhibited favorable biocompatibility and mechanical performance, making it a potential candidate for the development of drug-releasing joint implants to combat prosthetic bacterial infections.
Herein, we fabricate an embedding structure at the interface between Pt nanoparticles (NPs) and CeO2-{100} nanocubes with surface defect sites (CeO2-SDS) through quenching and gas bubbling-assisted membrane reduction methods. The in-situ substitution of Pt NPs for atomic-layer Ce lattice significantly increases the amount of reactive oxygen species from 133.68 µmol/g to 199.44 µmol/g. As a result, the distinctive geometric structure of Pt/CeO2-SDS catalyst substantially improves the catalytic activity and stability for soot oxidation compared with the catalyst with no quenching process, i.e., its T50 and TOF values are 332 ℃ and 2.915 h-1, respectively. Combined with the results of experimental investigations and density functional theory calculations, it is unveiled that the unique embedding structure of Pt/CeO2-SDS catalyst can facilitate significantly electron transfer from Pt to the CeO2-{100} support, and induce the formation of interfacial [Ce-Ox-Pt2] bond chains, which plays a crucial role in enhancing the key step of soot oxidation through the dual activation of surface lattice oxygen and molecular O2. Such a fundamental revelation of the interfacial electronic transmission and corresponding modification strategy contributes a novel opportunity to develop high-efficient and stable noble metal catalysts at the atomic level.
Sensitization of metal-centered forbidden transitions is of great significance. Solid MnⅡ-based phosphors with d-d forbidden transition sensitized by CeⅢ with d-f allowed transition are promising light conversion materials, but the energy transfer mechanism in CeⅢ-MnⅡ is still in dispute for the uncertainty of distances between metal centers. Herein, for the first time, we explored the energy transfer mechanism in two well-designed luminescent heteronuclear complexes with clear crystal structures, i.e., Ce-N8-Mn and Ce-N2O6-Mn (N8 = 1,4,7,10,13,16,21,24-octaazabicyclo[8.8.8]hexacosane; N2O6 = 4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane). Short distances between metal centers facilitate efficient energy transfer from CeⅢ to MnⅡ in both complexes, resulting in high photoluminescence quantum yield up to unity. After systematic study of the two heteronuclear complexes as well as two reference complexes Ce(N8)Br3 and Ce(N2O6)Br3, we concluded that dipole-quadrupole interaction is the dominant energy transfer mechanism in the heteronuclear complexes.
The quest for efficient and durable catalysts using abundant resources has garnered significant interest in the field of bifunctional oxygen electrocatalysis. In this contribution, we have designed a FeN4 or CoN4 embedded graphene-based bilayer as active layer and TMC3 or TMN3 doped graphene as supporting layer, named as FeN4/TMC3 or FeN4/TMN3 and CoN4/TMC3 or CoN4/TMN3, wherein TM strands for transition metal. Based on density functional theory calculations, our results demonstrate that the interaction formed between dual metal atoms in the bilayer interspace leads to the coordination environment altered from flat four-coordination to spatial five-coordination, further stabilizing the bilayer structure and impairing its affinity toward the O-containing intermediates. According to thermodynamic analysis, the bilayers of CoN4/CoN3, FeN4/FeC3, FeN4/CoC3, FeN4/NiC3, FeN4/ZnC3, FeN4/FeN3, FeN4/CrN3 and FeN4/ZnN3 are attractively promising for bifunctional oxygen electrocatalysis due to the small overpotential difference Δη between oxygen reduction and oxygen evolution that are less than 1 V. Density functional theory calculations combined with machine learning analysis directly identify the key role played by the inter-binding formed between bilayers, that boosts catalytic activity, which establishes a predictable framework for a fast screen for graphene-based bilayer vertical heterojunction. This work opens up a new path for designing the efficient electrocatalysts via modification of coordination environment.
The development of innovative and sustainable catalytic strategies for organic synthesis is a pivotal aspect of advancing material science and chemical engineering. This research presents a new catalytic method for the aminoacylation of N-sulfonyl ketimines by utilizing a potassium-doped graphite-like carbon nitride (g-C3N4) framework. This method not only enhances the catalytic efficiency and broadens the light absorption spectrum of g-C3N4 but also significantly reduces the recombination rate of electron-hole pairs, thereby increasing the reaction yield and selectivity. Importantly, our approach facilitates the synthesis of aminoacylated N-heterocycles, expanding the applicability of potassium-modified g-C3N4 in photocatalytic organic synthesis. A notable accomplishment of this study is the unprecedented generation of carbamoyl radicals via heterogeneous photocatalysis, which can be easily recycled after reaction. This advancement highlights the capability of potassium-doped g-C3N4 (namely K-CN) as an advanced heterogeneous photocatalyst for the formation of complex organic compounds.
Preparing free-base porphyrinoid radicals that can function as coordination ligands is a challenging task. Here we report the synthesis of a stable, free-base benzocorrole (BC) radical containing only two inner NH protons via a retro-Diels-Alder conversion. The radical character of BC was fully supported by crystallographic analysis, spectroscopic evidence, and theoretical calculations. This neutral radical ligand allowed easy insertion of Zn(Ⅱ), Ga(Ⅲ), and Pd(Ⅱ) ions to produce radical complexes. All these radicals exhibited luminescence-on responses under weak reducing atmosphere, corresponding to the conversion to their aromatic anions. The red fluorescence was observed for BC and its Zn(Ⅱ) and Ga(Ⅲ) complexes, and the near-infrared phosphorescence (> 900 nm) was detected for Pd(Ⅱ) complex at room temperature. Furthermore, Ga(Ⅲ) corrole exhibited a variation in fluorescence in response to axial coordination. Our findings provide a promising radical platform for coordination and developing novel functional materials with switchable spin and emission.