Journal of Materials Chemistry B最新文献

To date, various biodegradable polymers have been synthesized due to the merits of biodegradable polymers in biomedical applications. The current widely used biodegradable polymers generally have linear structures, such as poly(lactic-co-glycolic acid) (PLGA), which prevents polymer crosslinking and polymer modification via covalent conjugation, thus restricting their even broader applications. In this research, we report the synthesis and studies of new sustainable polymers consisting of biodegradable backbones and side chains, which endow the polymers with complete biodegradability, biocompatibility, crosslinking, and availability for covalent chemical modifications. The convenient synthesis of the polymers needs no catalyst under ambient conditions, which effectively avoids the unintended toxicity and immune response associated with the catalyst residues in the polymer materials. Therefore, these polymers are especially desired in biomedical materials and devices. Moreover, the polymers can be fabricated into gel materials and nanomaterials. Using a near-IR fluorescent probe as an indicative cargo, we have established a biodegradable and biocompatible agent-delivering nanosystem paradigm with an average nanoscale size of ∼50 nm. In the nanoarchitectures, the cargo molecules are tethered to the nanoparticulate scaffold through covalent conjugation, preventing unwanted premature release of the cargo molecules in the blood circulation and thus circumventing the related systemic toxicity and adverse effects. Further, the delivery nanosystems are available for facile decoration with targeting ligands to attain disease-targeted delivery. The new materials exhibited excellent in vivo biocompatibility, signifying the immense potential they hold for biomedical applications.

Background: Astragalus polysaccharide-containing 3D-printed scaffolds show great potential for cartilage defect repair. The aim of this study is to investigate their repairing role, combine them with metabolomics technology to deeply analyze the related metabolite changes, and provide a new strategy for the treatment of cartilage defects. Methods: Biocompatible astragalus polysaccharide-containing 3D-printed scaffolds were prepared. Thirty New Zealand rabbits were divided into normal, model and scaffold groups, with 10 rabbits in each group. The repair of cartilage defects by the scaffolds was evaluated by gross observation, micro-CT, HE and ABH staining after 12 weeks of intervention. The expression of VEGFA, Col2a1 and Biglycan was detected by immunofluorescence. Newly formed cartilage tissues were collected for metabolomics analysis to comprehensively evaluate the mechanism of action of astragalus polysaccharide-containing 3D-printed scaffolds in cartilage repair. Results: The recovery of cartilage defects in the scaffold group was found to be significantly better than that in the model group and comparable to that of the normal group by gross observation, micro-CT, HE and ABH staining. Immunofluorescence results showed that the expression of VEGFA, Col2a1 and Biglycan in the scaffold group was higher than that in the model group (all P < 0.05), comparable to that in the normal group. Metabolomics revealed that 29 metabolites were reversed in the scaffold group, with a reversal rate of 58%. The reversal mainly included groups of phospholipids, sphingolipids, purines, amino acids and energy metabolism-related changes. Fifteen metabolic pathways may be involved, and phospholipid and sphingolipid metabolism, fatty acid metabolism and purine metabolism are the major differential metabolic pathway change groups. Conclusion: Astragalus polysaccharide-containing 3D-printed scaffolds may accelerate cartilage collagen matrix remodeling, correct cartilage tissue metabolic disorders by promoting the expression of vascular-related factors, and ultimately promote cartilage repair.

A novel platinum(II) complex based on a terpyridine skeleton was developed to achieve a metal complex that interacts with the DNA of tumor cells with higher affinity. 1-(4-([2,2′:6′,2′′-Terpyridin]-4′-yl)phenyl)piperidine-4-carboxylic acid (CPT) was selected as the organic ligand, and a complex of CPT and Pt (CPT–Pt) was afforded through a hydrothermal approach. The MTT assay demonstrated that CPT–Pt exhibited higher antiproliferation against BxPC-3 cells with an IC₅₀ value of 6.26 μM. Moreover, the apoptosis rate of BxPC-3 cells in the CPT–Pt group was up to 77.5% at 30 μM, which was 1.7-fold higher than that of the oxaliplatin group, as tested using flow cytometry. CPT–Pt arrested BxPC-3 cells at the G2 phase in cell cycle progression. The molecular mechanism study showed that CPT–Pt promoted the accumulation of intracellular ROS and induced the loss of mitochondrial membrane potential. The results of UV absorption spectra, fluorescence spectra and molecular docking showed that CPT–Pt interacted with DNA through hydrogen bonds. Moreover, DNA cleavage was observed through gel electrophoresis. In a xenograft pancreatic cancer model, the tumor volume in the CPT–Pt group decreased by 75%, indicating that CPT–Pt effectively inhibited tumor growth in vivo. These findings provide a practical strategy for the rational design of novel Pt(II) complexes to improve their preclinical therapy of pancreatic cancer.

Poly-ether-ketone-ketone (PEKK) exhibits a bone-matching elastic modulus, commendable modifiability, and 3D-printable processability. These attributes enable its application in customized porous implants with optimized mechanical compatibility and osteogenic potential, particularly for orthopedic and dental regenerative therapies. This review evaluates the chemical characteristics, crystallization behavior, and mechanical properties of PEKK, alongside current strategies for material modification and additive manufacturing tailored to clinical requirements. Thus, PEKK-based restorative solutions exhibit great flexibility and adaptability when facing complex restorative demands of orthopedics and dentistry. The potential of PEKK in fields such as orthopedic surgery, dentistry, tissue engineering, drug delivery, and regenerative medicine is promising, with a possibility to serve as an alternative to traditional metal materials. However, the advantages of PEKK are not yet sufficient to supplant currently widely used implant material and further in-depth research and long-term evaluation is required.

In this study, we developed dynamic and supramolecular structures to combat the highly resistant pathogen Acinetobacter baumannii. This Gram-negative ESKAPE pathogen has a strong ability to form biofilms, which raises a key but challenging question: how to discover molecules active on both planktonic bacteria and their biofilms. To achieve this, we introduce two non-covalent ordered systems with antimicrobial and antibiofilm effects based on two distinct types of interactions: dynamic covalent bonding and supramolecular self-assembly. We discovered and optimized potent systems based on a cationic dynamic constitutional framework and a pillararene–antibiotic self-assembled drug delivery system through a synergistic screening process. Our screening methodology is based on searching for the synergistic effect of subcomponents to determine their optimal combinations and optimize their antibacterial potency. Crucially, our synergistic screening approach not only enables the rapid optimization of component combinations but also demonstrates the potential to generate potent bioactivity from individually inactive molecules and transform antibiotics with poor antibiofilm efficacy into highly active supramolecular systems, offering a significant advancement in combating challenging pathogens, such as A. baumannii.

Breast cancer is one of the most harmful diseases affecting human health. Low drug accumulation at the tumor site and the severe side effects of traditional chemotherapeutics compromise their effectiveness in breast cancer treatment. Utilizing nanocarriers for targeted delivery and controlled release of therapeutics to cancer cells could be a promising pathway to alleviate these problems. Herein, we synthesized a novel prodrug conjugate coupling hydrophilic fructooligosaccharide with hydrophobic tamoxifen via a reactive oxygen species (ROS)-responsive aryl boronic ester linker, these amphiphilic conjugates could self-assemble into nanoparticles with high drug loading capacity and realize not only active breast cancer targeting via fructooligosaccharide moiety, but also controlled drug release through boronic ester bond breakage in higher ROS levels of the tumor cells. These nanoparticles showed specific cellular internalization and targeted cytotoxicity in MCF-7 breast cancer cells. To evaluate the hepatotoxicity of nanodrugs, a liver organoid model was established to simulate the in vivo metabolism of nanodrugs and assess their activities in the liver tissue. The results demonstrated that a low concentration (25 μg mL⁻¹) of nanodrugs could inhibit cellular proliferation of breast cancer cells significantly without showing obvious toxicity to liver organoids, implicating a favorable efficacy and safety profile of these nanodrugs. Therefore, the tamoxifen-loaded fructose-based nanodrug might be a promising platform for improving tumor targeting and reducing side effects in breast cancer treatment.

The charge-reversal strategy has been of great significance for enhancing the penetration of nanomedicines in tumors. However, conventional charge reversal has always been confined to pH variation. Herein, we proposed a pH-independent charge-reversal strategy based on hyaluronidase-responsive polycarbonate nanocarriers bearing quaternary ammonium groups. We developed multifunctional polycarbonate-based nanocarriers using tellurium/quaternary ammonium-containing carbonate copolymers. The encapsulation of cisplatin was achieved through coordination complexation with tellurium atoms. The positive charge was shielded from the circulation in vivo by the modification of hyaluronic acid and then exposed in HAase. In vitro cell experiments confirmed the selective killing effect of the drug carriers on pancreatic tumor cells and revealed a mitochondria-targeted pro-apoptotic mechanism. In vivo animal experiments verified the anti-tumor ability and significant tumor tissue penetration ability of the drug carriers. Therefore, the proposed pH-independent deep-tumor-penetration nanocarriers provide a potential nanoplatform for the stable clinical treatment of dense solid tumors.

In recent years, the development of high-throughput DNA synthesis technology has significantly advanced research in genomics and synthetic biology. Traditional DNA synthesis methods, such as first-generation DNA synthesizer and PCR-based approaches, have demonstrated excellent performance in many aspects. However, they exhibit notable limitations in de novo synthesis of long-chain DNA and large-scale parallel synthesis. Second-generation high-throughput DNA synthesis technologies, including photolithographic, inkjet, electrochemical, and thermally controlled synthesis techniques based on microarray chips, have shown remarkable advantages in improving synthesis efficiency, reducing costs, and increasing throughput. However, these methods rely on chemical principles, making it challenging to overcome issues related to short sequence length and environmental pollution. This has led to the emergence of third-generation enzymatic synthesis technologies, which offer distinct advantages in environmental sustainability and long-chain DNA synthesis, demonstrating great application potential. This review defines microarray-based synthesis as the boundary for high-throughput synthesis, categorizing previous methods as traditional synthesis technologies. It systematically elaborates on mainstream high-throughput synthesis technologies, analyzing and comparing their advantages and limitations. Furthermore, it explores their applications in life sciences, medicine, and other fields. Finally, potential technological advancements and application expansions are discussed, providing insights into the future development directions and challenges of high-throughput DNA synthesis technology, with the aim of offering valuable references for related research.

Quaternary ammonium and phosphonium compounds have been widely used as two important classes of antimicrobial agents worldwide. However, over-reliance and misuse of the limited antimicrobial agents have driven the development and spread of resistance of bacteria to these materials. Thus, overcoming the growing bacterial drug resistance is a challenging work in ensuring public health. In this work, we compiled two modules comprising photosensitizers and quaternary phosphonium blocks integrated into material networks via a co-polymerization method, resulting in desired antimicrobial materials with the capability to generate reactive oxygen species (ROS) and exhibiting high affinity towards negatively charged bacterial membranes. This synergistic effect enabled ROS to destroy bacterial membranes within an effective migration distance. As a result, poly(TPAs-2&P⁺-4) was optimized as a promising antibacterial agent, which demonstrated superior bacteria killing and imaging abilities against four bacteria lines, namely, E. coli, methicillin-resistant S. aureus, E. faecalis and P. aeruginosa. The minimum inhibitory concentration (MIC) was determined as 75 μg mL⁻¹ for E. coli and methicillin-resistant S. aureus and 150 and 350 μg mL⁻¹ for E. faecalis and P. aeruginosa, respectively.

Correction for ‘Virus-like particles nanoreactors: from catalysis towards bio-applications’ by Yuqing Su et al., J. Mater. Chem. B, 2023, 11, 9084–9098, https://doi.org/10.1039/D3TB01112G.