查找使用阿拉丁产品的科研文献

Extrusion deposition 3D printed PCL/gel/n-HA composite scaffold for bone regeneration

Chenxin Wang,Jie Liu,Mingyue Lin,Rui Zhang,Yufan Li,Yubao Li,Qin Zou

Attapulgite-doped electrospun PCL scaffolds for enhanced bone regeneration in rat cranium defects

Ting Dai,Jiayi Ma,Su Ni,Chun Liu,Yan Wang,Siyu Wu,Jun Liu,Yiping Weng,Dong Zhou,Ana Jimenez-Franco,Hongbin Zhao,Xiubo Zhao

Electrospun PCL scaffolds have been widely used for tissue engineering as they have shown great potential to mimic the structure of the natural extracellular matrix (ECM). However, the small pore size and low bioactivity of the scaffolds limit cell migration and tissue formation. In this study, PCL (polycaprolactone), PCL/PEG (polyethylene glycol), and PCL/PEG/ATP (nano-attapulgite) scaffolds were fabricated via electrospinning. To increase the porosity of the scaffolds, they were washed to remove water-soluble PEG fibers. Then the porous structure was measured using scanning electron microscopy (SEM) and atomic force microscopy (AFM), which showed an increased porosity when PEG fibers were removed in PCL/PEG and PCL/PEG/ATP scaffolds. Moreover, the mechanical properties were also analyzed in dry and wet conditions. In vitro mouse multipotent mesenchymal precursor cells were used to assess the biocompatibility of the scaffolds, and osteogenesis was analyzed using CCK-8 and real-time PCR (RT-PCR) methods. Moreover, in vivo μCT, histological and immunohistochemical analyses were conducted to evaluate new bone formation in rat cranium defect models. Washed PCL/PEG/ATP scaffolds were implanted into the cranium defects in rats for 4 or 8 weeks, better cell infiltration was observed in these scaffolds than in unwashed ones. The result demonstrated that washed PCL/PEG/ATP scaffold facilitated the differentiation of MSCs into osteoblasts compared with PCL scaffold, as proved by the increased expression of osteogenic key genes as well as Smad1, Smad4, and Smad5. Furthermore, in vivo studies demonstrated that using the ATP-doped electrospun PCL scaffold can improve the bone regeneration of rat cranium defects. Particularly, the PCL/ATP-30% scaffold has the best effect compared to the other scaffolds. The enhanced osteogenesis and bone repair were related to the PCL/ATP activated BMP/Smad signaling pathway.

An effective dual-factor modified 3D-printed PCL scaffold for bone defect repair

Yan Li,Qian Li,Hongming Li,Xiao Xu,Xiaoming Fu,Jijia Pan,Hui Wang,Jerry Ying Hsi Fuh,Yanjie Bai,Shicheng Wei

Numerous bioactive molecules produced in cells are involved in the process of bone formation. We consider that appropriate, simultaneous application of two types of bioactive molecules would accelerate the regeneration of tissues and organs. Therefore, we combined aspirin-loaded liposomes (Asp@Lipo) and bone forming peptide-1 (BFP-1) on three dimensional-printed polycaprolactone (PCL) scaffold and determined whether this system improved bone regeneration outcomes. in vitro experiments indicated that Asp@Lipo/BFP-1at a 3:7 ratio was the best option for enhancing the osteogenic efficiency of human mesenchymal stem cells (hMSCs). This was confirmed in an in vivo cranial defect animal model. In addition, RNA-Seq was applied for preliminarily exploration of the mechanism of action of this composite scaffold system, and the results suggested that it mainly improved bone regeneration via the PI3K/AKT signaling pathway. This approach will have potential for application in bone tissue engineering and regenerative medicine.

An investigation on sunlight-induced shape memory behaviors of PCL/TiN composites film

Guangming Tian,Guangming Zhu,Shuogui Xu,Tianning Ren

Plasmonic materials possess good optical properties in effectively converting solar energy into heat, here a series of sunlight responsive shape memory composites films based on acrylate-terminated Poly (ε-caprolactone) (PCL) and titanium nitride nanoparticles (TiN NPs) are prepared via base-catalyzed Michael addition. Compared with conventional free radical polymerization or physical blending, this paper constructs a network architecture from view of structural controllability, favoring a subsequent flexible and elastic materials as well as fine dispersion of TiN NPs in the cross-linked networks, the resultant materials show an outstanding mechanical and the incorporated TiN NPs enable rapid temperature increase over the melting temperature of PCL and trigger the shape change of the composite with good shape recovery rate. The effect of light density and TiN NPs concentration on composite film are elucidated and investigated systematically, it is found that the amount of TiN NPs content virtually has a negligible effect on the surface temperature of the films when subjected to a specific illumination, however, light intensity has a remarkable influence on it. Furthermore, an electronics device switch actuated by 160 mw cm−2 simulated sunlight irradiation is demonstrated and envisioned for flexible electronic applications.

Fe3O4/ poly(caprolactone) (PCL) electrospun membranes as methylene blue catalyst with high recyclability

Wen Xue,Yang Hu,Fujun Wang,Xudong Yang,Lu Wang

High specific-surface-area porous poly(caprolactone) (PCL) membranes combined with Fe 3 O 4 nanoparticles were fabricated by electrospinning technology. Their applications as catalysts in Fenton reactions to degrade methylene blue (MB) were evaluated in the presence of H 2 O 2 and UV light . The results indicated that the fibrous catalyst system illustrated efficient MB removal performance (99% of MB degradation rate) and was viable after 6 cycles (96% of MB degradation rate). Besides, the morphology, chemical composition , magnetic and mechanical properties were also accessed by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, magnetometry , and strain-stress curves. The outstanding catalytic behaviors of the composites are attributed to synergy of porous surface and embedded Fe 3 O 4 nanoparticles. It also shows advantages of being environment-friendly and separated easily without an external magnetic field.

Zinc oxide/silver bimetallic nanoencapsulated in PVP/PCL nanofibres for improved antibacterial activity

Min Hu,Chenwen Li,Xin Li,Min Zhou,Jianbin Sun,Fangfang Sheng,Sanjun Shi,Laichun Lu

The anti-infection ability and skin regeneration are important aspects on the progress of wound healing, which needs an ideal wound dressing that not only resists bacteria but also promotes skin regeneration. In this study, zinc oxide/silver/polyvinylpyrrolidone/polycaprolactone (ZnO/Ag/PVP/PCL) nanofibres were prepared through electrospinning. Firstly, zinc oxide nanoparticles (ZnONPs) and silver nanoparticle (AgNPs) were synthesized respectively. Secondly, the two nanoparticles were mixed with polyvinylpyrrolidone (PVP) and polycaprolactone (PCL) to obtain the nanofibres. The results of scanning electron microscopy (SEM) showed that ZnONPs and AgNPs were 40.07 ± 9.70 nm and 37.46 ± 12.02 nm, respectively. After electrospinning, the nanofibres were 368.22 ± 123.96 nm in diameter. Infrared spectroscopy revealed that ZnONPs/AgNPs bimetallic nanomaterials were physically embedded in the nanofibres. The antibacterial effects against Staphylococcus aureus and Escherichia coli of ZnO/Ag/PVP/PCL nanofibres were significantly better than these of the single metal material-loaded nanofibres. More importantly, the combination of ZnO and Ag reduced the cytotoxicity of ZnO/Ag/PVP/PCL bimetallic nanofibres toward fibroblasts. These findings demonstrated that ZnO/Ag/PVP/PCL bimetallic nanofibres should be of greater interest than the single metal nanomaterial-loaded nanofibres in inhibiting growth of bacteria.

Tuning the crystallinity and degradability of PCL by organocatalytic copolymerization with δ-hexalactone

Qilei Song,Yening Xia,Shuangyan Hu,Junpeng Zhao,Guangzhao Zhang

The copolymerization of ε -caprolactone (CL) with its structural isomer , δ -hexalactone (HL), or trimethylene carbonate (TMC) catalysed by diphenyl phosphate was investigated. Copolymers with molar fraction of CL units ranging from 54% to 95% were obtained. Molecular characterization exhibited random distribution of the two monomeric units (CL/HL or CL/TMC), owing to the extensive occurrence of transesterification scrambling reactions at high temperature. Compared with poly( ε -caprolactone) (PCL), the copolymers showed reduced crystallinity and enhanced enzymatic degradability as revealed by the analysis with differential scanning calorimetry and quartz crystal microbalance with dissipation, respectively. Interestingly, the incorporation of HL units showed a more profound impact than TMC. It is therefore considered that organocatalytic copolymerization with HL, a bio-renewable lactone, can serve as an effective method to regulate the properties of PCL.

Microscale electrohydrodynamic printing of biomimetic PCL/nHA composite scaffolds for bone tissue engineering

Xiaoli Qu,Peng Xia,Jiankang He,Dichen Li

Electrohydrodynamic printing provides an innovative strategy to fabricate high-resolution tissue-engineering scaffolds with fiber orientation and scale similar to native extracellular matrix. However, few studies have been conducted to incorporate functional nanobiomaterials into microscale fibrous structures. In this study, we presented to fabricate microscale poly (ε-caprolactone) (PCL) and hydroxyapatite nanoparticles (nHA) composite scaffolds with the average fiber diameter of 8.85±1.12   µm based on electrohydrodynamic 3D printing to better mimic collagen fibers and HA nanocrystals in natural bones. The composite scaffolds exhibited good biocompatibility and facilitated cell alignment and proliferation in vitro . This strategy might be useful to regulate cellular microenvironment in multiscale and multimaterial levels for improved tissue regeneration.

Preparation of pCL-20/PTFE-Al composites for sensibility reduction and combustion improvement

Lanting Yang,Zhaokang Chen,Lihao Wang,Zhenwei Zhang,Ruihao Wang,Changping Guo

The high sensitivity of high explosive hexanitrohexaazaisowurtzitane (CL-20) limits its applicability, and the performance optimization brought by the synergistic effect between nanothermite and CL-20 is expected to expand its application prospects. In this study, polydopamine (PDA) was introduced to modify CL-20 (denoted as pCL-20), and a quasi-core/shell pCL-20/polytetrafluoroethylene-aluminum (pCL-20/PTFE-Al) composite was successfully prepared by ultrasonic-assisted composite method. The performance characterization results demonstrate that the composite exhibits significantly better decomposition heat release than the mixed sample, a reduction in combustion time from 408 ms to 268 ms, a more stable combustion flame, and more focused energy release. At the same time, the comparison of composite combustion with different condition variables reflects the combustion advantages of the selected proportional conditions in this study. The characteristic drop height (H 50 ) increased from 24.05 cm to 42.15 cm, the explosive percentage of friction sensitivity reduced from 100 % to 70 %, and the sensitivity of the composite sample decreased significantly when compared to the raw CL-20. It improves the combustion performance while reducing the sensitivity, thereby enhancing the application potential and providing a reference for the high-energy desensitization of energetic materials.

AuNPs-PCL nanocomposite accelerated abdominal wound healing through photothermal effect and improving cell adhesion

Cheng Zhao,Xiuwen Wu,Guopu Chen,Feng Wang,Jianan Ren

Accelerating wound healing with modified biomaterial has been an attracting field in both material science and medicine. Enhanced cell adhesion could be acquired by improving surface hydrophilicity, which contributes to accelerating wound healing. Chemical reaction has been used for surface modification, but this study used a simple and nontoxic method to improve the hydrophilicity. Polycaprolactone (PCL) scaffold has been regarded as promising material for wound healing while its surface is hydrophobic. Our study demonstrated enhanced hydrophilicity of PCL with AuNPs coating. AuNPs has good biocompatibility and excellent photothermal effect. The coating of AuNPs not only improved the cell adhesion, but also gave PCL the ability to inhibit the growth of bacteria. Animal study showed that the nanocomposites decreased lymphocytes and neutrophils, increased neovascularization and accelerated the abdominal wound healing, which was attributed to improved hydrophilicity and the antibacterial ability. In conclusion, we demonstrated that the nanocomposite could be used as a potential scaffold for cell adhesion and wound healing, and the role of AuNPs was highlighted as a kind of outstanding supplement.

Electrospun PLGA/PCL/OCP nanofiber membranes promote osteogenic differentiation of mesenchymal stem cells (MSCs)

Zetao Wang,Ruiming Liang,Xianfang Jiang,Jiali Xie,Peian Cai,Haimin Chen,Xintang Zhan,Danqing Lei,Jinmin Zhao,Li Zheng

Nanofibers as niche-biomimetic scaffolds hold promise in guided bone regeneration (GBR). Here we fabricated poly (lactic- co -glycolic acid) (PLGA)/poly(caprolactone) (PCL)-doped octacalcium phosphate (OCP) nanofiber membranes via electrospinning and investigated the osteogenic behavior of marrow mesenchymal stem cells (MSCs) on the membranes. By adjusting different ratio of OCP to PLGA/PCL, three hybrid stents including PLGA/PCL, PLGA/PCL/2 wt%OCP, PLGA/PCL/4wt%OCP were successfully prepared. The PLGA/PCL/OCP membranes showed a decrease in fiber diameter compared with PLGA/PCL, leading to enhanced mechanical strength. In-vitro studies showed that PLGA/PCL/OCP membranes better supported cell adhesion, spreading and proliferation than PLGA/PCL. The incorporation of OCP via electrospinning also endowed the membranes with osteoinductive capacity, as evidenced by activation of ALP activity, increased gene expression of bone specific markers (such as Runx2 , ALP , Col 1a1 , OPN , OCN , BMP2 ), and mineral nodules formation compared to PLGA/PCL. Comparatively, PLGA/PCL/4wt%OCP showed better mechanical and biological performance than PLGA/PCL/2 wt%OCP, demonstrating the role of OCP in nanofiber membranes. Thus, the electrospun PLGA/PCL/OCP nanofiber membranes can be potentially developed as a promising hybrid stent for GBR.

Multifunctional CeO2/PCL Nanofibrous Scaffold with Integrated pH Sensing and Enhanced Stem Cell Adhesion

Chi Chunyu,Gao Yuantao,Chen Jiazhu,Ge Xuejun,Gao Zexing,Li Yinggang,Yan Shuang

The delayed healing of skin wounds poses significant health risks and increases medical burdens, necessitating the development of multifunctional dressings that can actively monitor and promote the healing process. In this study, a multifunctional CeO 2 /PCL nanofibrous scaffold integrating real-time pH sensing, enhanced stem cell adhesion, and antioxidant functions was developed. A series of composite scaffolds with tunable CeO 2 nanoparticle loadings (7.1–31.6 wt %) were fabricated via a facile one-step electrospinning technique. Notably, the CeO 2 /PCL-13.3 wt % scaffold achieved an optimal balance of tensile strength (1.927 MPa) and elongation at break (70%), fully satisfying clinical wound dressing requirements. Phenol red loading enabled naked-eye pH monitoring (4.0–10.0) via metal−phenolic coordination. Comprehensive evaluations demonstrated that the composite scaffolds exhibited significant antibacterial activity, potent reactive oxygen species scavenging capability, and excellent biocompatibility. The scaffolds maintained over 80% human umbilical cord mesenchymal stem cells viability within 72 h and significantly promoted stem cell migration in wound healing assays. This integrated platform unifies visual diagnostics and therapeutic functions for advanced wound management.