Journal of Materials Chemistry B最新文献

Rapid repair and functional reconstruction of maxillofacial bone defects is a significant challenge in the field of stomatology. Artificial bone substitute materials show promising potential in maxillofacial bone regeneration. This study investigated the bone regenerative effects of platelet concentrate/mesoporous bioactive glass (MBG) composite scaffolds, comparing injectable platelet-rich fibrin (i-PRF) and gel-phase concentrated growth factors (gpCGF). In vitro results showed though gpCGF excelled in promoting proliferation and migration of bone marrow mesenchymal stem cells (BMSCs) compared to i-PRF, in the in vivo rabbit mandibular defect model, i-PRF/MBG composite scaffolds showed superior bone regenerative outcomes, as assessed by Micro-CT and histological analyses. The simpler in situ preparation process of i-PRF-composited scaffolds resulted in higher retention of active components, while the complex extraction and preparation of gpCGF might have compromised its bioactivity. This study highlights the potential of i-PRF/MBG composite scaffolds in enhancing bone regeneration and suggests that i-PRF, with its higher concentration of bioactive factors and feasibility of compositing with scaffolds, offered an economically efficient solution for clinical bone repair, providing new insights for the development of future orthopedic biomaterials.

Photodynamic therapy (PDT) offers a promising, non-invasive approach to cancer treatment. However, its efficacy is often limited by the poor water solubility, low cellular uptake, and high dose requirements of traditional photosensitizers, which can lead to side effects like skin photosensitivity. This study presents a novel supramolecular photosensitizer, PS3⊂WP5, comprising a mannosylated pillar[5]arene (WP5) host and a near-infrared BODIPY photosensitizer (PS3). This host–guest complex exhibits a strong binding affinity (K_a = 5.10 × 10⁶ M⁻¹) and self-assembles into nanoparticles in water. PS3⊂WP5 demonstrates high singlet oxygen quantum yield (Φ_Δ = 0.95) upon irradiation at 633 nm, along with excellent photostability. In vitro experiments confirm that PS3⊂WP5 exhibits superior PDT efficacy, good biocompatibility, and low dark toxicity compared to the free PS3, which suffers from poor aqueous solubility, low stability, and limited cellular uptake. This supramolecular approach offers a promising strategy for the design of multifunctional nanomaterials for cancer phototherapy, potentially overcoming the limitations of conventional photosensitizers and paving the way for the development of more efficient PDT agents with enhanced clinical potential.

During tissue repair, stress-induced cellular senescence represents a critical factor that impedes the regenerative potential of tissues. While the regulatory effects of matrix viscoelasticity on cellular behavior have been documented, their role and correlated mechanisms underlying cellular senescence remain unclear. In this study, we engineered a viscoelastic gel matrix exhibiting a storage modulus of approximately 3 kPa, with a tunable loss modulus ranging from 0 to 300 Pa by incorporating linear alginate and modulating the compactness of a polyacrylamide-based covalent network. Utilizing a UV-induced senescence model, we observed that increasing the matrix's viscoelasticity from 0 Pa to 300 Pa led to a significant reduction in the proportion of senescent cells, from 90.5% to 22.7%. Furthermore, cells cultured in these matrices exhibited a tendency to form cell aggregation, with the cell populations demonstrating a collective resistance to stresses. This indicated that viscoelastic materials would promote enhanced cellular interactions, thereby strengthening cellular resilience against UV-induced stresses. Furthermore, combined with microarray analysis, it was concluded that the presence of viscoelastic components activated the connexin 43 (Cx43)-modulated gap junction for cluster formation, thereby suppressing the senescence-associated signaling pathways, including Wnt/β-catenin, MAPK, NF-κB, and TGF-β. Additionally, the integrin–cytoskeleton–Yes-associated protein (YAP) signaling axis played an active role in delaying cell aging. These results provide novel insights into the regulatory role of viscoelastic materials in cellular senescence and offer a compelling foundation for the development of advanced biomaterials for tissue repair.

Dye-based photoremovable protecting groups (PRPGs) are explored for biological applications because they release bioactive molecules by absorbing light at higher wavelengths, and their self-fluorescent properties make them suitable for cellular imaging and image-guided photorelease inside the cells. Henceforth, we modified fluorescein dye to a cinnamyl-based PRPG for the release of alcohols to overcome the limitations of multiple photoproduct formation. The carboxylic acid group at C1 and the phenolic-OH group at the C6 positions in the fluorescein PRPG resulted in interesting pH-sensitive photophysical properties due to their existence in different forms (lactone, quinoid, monoanionic, dianionic) at different pHs, which is well supported by theoretical studies. Caged esters (3a–e) of fluorescein-based PRPG released the corresponding alcohols with good chemical yields and moderate photouncaging quantum yields upon exposure to green light. To enhance the biological utility, our developed fluorescein PRPG was formulated as nanoparticles (Nano-3d) having better cell penetration and accumulation. Interestingly, the fluorescein-based PRPG exhibited a change in fluorescence after photorelease ensuring its real-time monitoring ability in biological media. Furthermore, green light (525 ± 5 nm) exposure of our prepared nanoparticles (Nano-3d) released the bioactive molecule menthol within the MCF-7 breast cancer cell line causing effective cytotoxicity after photorelease. Hence, this development of a fluorescein-based PRPG can contribute to advancements in dye-based image-guided nanodrug delivery systems.

As a novel approach to killing bacteria, photodynamic therapy holds great potential in antibacterial treatment. However, the majority of traditional photosensitizers exhibit relatively low reactive oxygen species (ROS) quantum yield. Therefore, it is essential to develop photosensitizers with high ROS quantum yield to effectively kill bacteria. Herein, we propose a molecular design approach to enhance the spin–orbit coupling (SOC) and improve the ROS quantum yield by introducing carbonyl groups into a donor–acceptor (D–A) system. In the meantime, we also introduced membrane-anchoring functional groups to the photosensitizer to anchor on the bacterial surface for improved antibacterial treatment. In this design, two D–A photosensitizers (CTI-1-anchor and CTI-2-anchor) were synthesized by linking membrane-anchoring functional groups to carbazole and indanedione derivatives. Notably, the resulting CTI-1-anchor exhibited a significantly enhanced ROS generation capability, and its ROS quantum yield can reach 87%. Moreover, the CTI-1-anchor demonstrated superior antibacterial performance against Gram-positive bacteria (S. aureus) and Gram-negative bacteria (E. coli). The antibacterial efficacy of CTI-1-anchor reached 97.7% and 73.4% for S. aureus and E. coli, respectively. This study is expected to inspire further molecular designs of photosensitizers, ultimately contributing to the development of efficient antibacterial therapy.

With the growth of the elderly people and the development of transcatheter aortic valve replacement (TAVR) technology, bioprosthetic heart valves (BHVs) originating from the decellularized bovine pericardium (DBP) have become a favourable option for severe valvular heart disease (VHD). However, currently, available commercial bioprosthetic heart valves prepared from glutaraldehyde (GA)-crosslinked xenografts have limited durability because of various factors, including severe cytotoxicity, inflammatory response, poor pro-endothelialization ability and calcification. Therefore, the development of valve materials with better performance is urgent. In this work, we first synthesized Cu-doped carbon dots (CuCDs) with excellent biocompatibility and high stability using sodium citrate, ethylenediamine and copper chloride. Subsequently, oxidized chondroitin sulfate (OCS) was used to crosslink the decellularized bovine pericardium to obtain OCS–BP followed by loading CuCDs onto the surface of this OCS-fixed BP sample through amide bonds formed by an EDC/NHS-catalyzed reaction between the functional groups on CuCDs and OCS–BP to prepare the BHV (CuCDs–OCS–BP) with specific properties. Relevant experiments conducted both in vivo and in vitro indicate that CuCDs–OCS–BP with good stability showed improved mechanical properties, compliance and flexibility, encouraging HUVEC-cytocompatibility, excellent anti-blood cell adhesion, antithrombogenic properties, anti-inflammatory and anti-calcification properties, and a good endothelialisation ability due to the catalytic generation of endogenous nitric oxide. Overall, CuCDs–OCS–BP is a promising material for BHVs.

Uric acid (UA), the final product of purine metabolism, is a crucial biomarker for gout diagnostics and highly related to various metabolic diseases. Precise detection of UA levels in serum and urine enables disease diagnosis and guides treatment. Combining the advantages of colorimetry and laser desorption/ionization mass spectrometry (LDI-MS), we developed a dual-model biosensor based on hollow Cu₂O@Au nanocubes (h-Cu₂O@Au NCs) for UA detection. The h-Cu₂O@Au NCs demonstrated excellent peroxidase (POD)-like activity and were used to rapidly detect UA by colorimetric assay, with a linear range of 0.05–2 mM and limit of detection (LOD) of 35.71 μM. Moreover, the h-Cu₂O@Au NCs achieved enrichment and detection of UA via the liquid–liquid interface self-assembly-assisted LDI-MS, with a linear range of 0.01–0.5 mM, LOD of 15.6 μM, and reproducibility of <5%. In view of its advantages, the dual-model nanoplatform based on h-Cu₂O@Au NCs achieved UA detection in serum samples by colorimetry assay and in urine samples by LDI-MS, obtaining results consistent with the commercial UA assay kit (72–511 μM for serum, R² = 0.956 and 2–9 mM for urine, R² = 0.876), presenting potential in the rapid and sensitive detection of UA in clinic.

Carbon nanotube (CNT) composite hydrogels are promising materials for tissue engineering due to the biocompatibility of the matrix and the electrical conductivity of the filler, which is crucial for promoting the growth and functions in electroactive tissues. While pristine CNTs are insoluble, we synthesized and fully characterized a water-soluble CNT derivative (fCNT) bearing quaternary ammonium groups, and we homogeneously dispersed it within alginate-based hydrogels. Through external and internal gelation we obtained two plain and two fCNT-filled hydrogels (HG1 and HG2 and HG1-fCNT and HG2-fCNT, respectively), and we compared the physical properties of the four different materials. A measurement setup and an approach were specifically designed for the electrical characterization of our hydrogel samples, showing that the addition of a low amount (0.1 mg mL⁻¹) of fCNT enhanced the conductivity of the hydrogel from internal gelation (HG2-fCNT) by more than one order of magnitude, from 5.7 × 10⁻¹⁰ to 2.8 × 10⁻⁸ S cm⁻¹. Even more interestingly, HG2-fCNT featured a faster transmission of low frequency signals (with time scales from 1 ms to 100 ms, typical of electroactive biological tissues) than the other samples. Finally, the behavior of the four hydrogels as scaffolds for muscle tissue engineering was compared through studies of myoblast viability, proliferation, and differentiation. A relevant improvement in differentiation (more than doubling the number and area of myotubes and the fusion index) was obtained by adding the fCNT in the case of HG2-fCNT, in line of its superior electrical properties. These outcomes hint at the feasibility of using the fCNT combined with the alginate hydrogel in order to support the myoblast growth and proliferation.

Nanozymes, as synthetic nanomaterials that catalyze the conversion of enzyme substrates to products and follow enzymatic kinetics, have emerged as powerful agents for combating oxidative stress-related diseases by scavenging reactive oxygen species (ROS). In recent years, constructing multifunctional integrated systems by integrating nanozymes with therapeutic drugs or endowing them with efficient delivery capabilities through surface functionalization strategies has become one of the cutting-edge directions. This review explores recent progress in three key surface modification approaches—chemical conjugation, physical encapsulation, and drug loading—that collectively enable synergistic therapeutic effects, precise targeting, and effective penetration of biological barriers. Chemical conjugation allows for the direct attachment of molecules to nanozyme surfaces, enhancing synergistic efficacy and targeting specificity. Physical encapsulation using mesoporous structures, hydrogels, or microneedles improves nanozyme stability, extends in vivo retention, and facilitates controlled release. Drug-loading strategies further expand the therapeutic potential by enabling co-delivery of antioxidants and other functional agents to complex pathological environments. Despite these promising advancements, challenges remain in elucidating the fundamental catalytic mechanisms of nanozymes, ensuring long-term biocompatibility, and achieving scalable clinical translation. Future efforts should focus on developing dynamically responsive systems, achieving precision catalysis, and fostering interdisciplinary integration to accelerate the evolution of nanozyme-based therapeutics. This review systematically summarizes the modification strategies from a surface perspective, offering insights for constructing multifunctional systems.

The incidence of dural tears is becoming increasingly common in spinal laminectomy procedures, particularly those involving nerve decompression surgeries or tumor resections. Therefore, ensuring proper sealing of the injured dura is crucial to prevent postoperative complications such as cerebrospinal fluid leakage, neural damage, epidural fibrosis, and local inflammation. This study presents the development of a UV-responsive pullulan-based sealant, chemically grafted with dopamine (DOPLS), which demonstrates rapid gelation capabilities of less than 30 s. The developed DOPLS sealant exhibited good adhesive strength on porcine skin (0.332 ± 0.05 MPa) and glass slides (1.6 ± 0.24 MPa). Furthermore, its ability to bond with wet tissue surfaces was tested on ex vivo tissues, including caprine dural tissue, porcine heart, and murine kidney. The burst pressure testing on caprine tissue revealed that DOPLS (442.78 ± 88.9 mmHg) could withstand sevenfold higher pressure compared to the unconjugated pullulan sealant (63.75 ± 32.8 mmHg). Moreover, the DOPLS sealant demonstrated superior viscoelastic characteristics, such as a wider linear viscoelastic regime, a higher elastic modulus, and improved structural stability compared to its unmodified counterpart. Its excellent shear-thinning behaviour, which is essential for injectable sealants, facilitates the delivery of DOPLS through narrow-gauge needles. Further, the DOPLS sealant was loaded with naringin (NDOPLS), a natural flavanone glycoside known for its pharmaceutical properties, which showed a sustained release of over 75% within 48 h. Naringin-loaded DOPLS also exhibited excellent anti-fibrotic activity in vitro, demonstrated by a notable reduction in α-SMA expression, and good cytocompatibility, with cell viability exceeding 90%. Overall, these findings suggest that this pullulan-based light-curable sealant incorporating dopamine and naringin could be an effective option for repairing spinal dural injuries by providing strong sealing, cytocompatibility, and promoting scarless healing.