查找使用阿拉丁产品的科研文献

A novel 3D printing PCL/GelMA scaffold containing USPIO for MRI-guided bile duct repair

Hehong Li,Yingxian Yin,Yang Xiang,Haixia Liu,Rui Guo

Making artificial bile ducts in vitro for repairing and replacing diseased bile ducts is an important concept in tissue engineering. This study printed a tubular composite scaffold using polycaprolactone (PCL) through the current 3D printing method. It served as a matrix for the organoid cells of the bile duct to proliferation, migration, and differentiation. The PCL scaffold full of bile duct-like organ cells can achieve the effect of bionics, replacing the original bile duct to perform its proper function. In order to enrich the performance of the tubular scaffold, hydrogels were also used in this study. Applying a layer of gelatin methacryloyl (GelMA) hydrogel with an appropriate thickness on the outer layer of the PCL scaffold not only protects and supports the scaffold, but also improves the biocompatibility of the printed bile duct. In addition, ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles dispersed in GelMA served as the contrast agent to monitor the repair of the lesion site and the degradation of the bile duct in real time by magnetic resonance imaging (MRI). In this study, a tubular composite scaffold that could reconstruct bile duct function and possess a real-time MRI imaging property was constructed by 3D printing. After 13 days of the co-culture of bone marrow derived stem cells (BMSCs), the survival rate of the BMSCs was greater than 95%, and the coverage of the BMSCs was as high as 90%. At the same time, the compression modulus of the stent could reach 17.41 kPa and the Young's modulus could reach 5.03 kPa. Thus, the mechanical properties of it can meet the needs of human implantation. USPIO can achieve MRI imaging in situ and nondestructively monitor the degradation of the stent in the body. In summary, PCL/GelMA/USPIO bile duct scaffolds are beneficial to the proliferation of cells on the scaffolds and can be used to construct biologically active artificial bile ducts.

Preparation and in vitro/in vivo evaluation of 6-Gingerol TPGS/PEG-PCL polymeric micelles

Lijun Zhen,Qiuyu Wei,Qilong Wang,Huiyun Zhang,Michael Adu-Frimpong,Caleb Kesse Firempong,Ximing Xu,Jiangnan Yu

6-Gingerol, an active herbal ingredient of ginger has various bioactivities such as anti-neurodegenerative disease, anti-inflammatory and so on. The aim of the present study was to enhance the oral bioavailability and brain distribution of 6-Gingerol via polymeric micelles. A polymeric micelles drug delivery system of 6-Gingerol consisting of D-α-Tocopheryl polyethylene glycol 1000 succinate (TPGS) and Poly (ethylene glycol)-poly (ε-caprolactone) (PEG-PCL) was prepared via solvent injection method. The developed 6-Gingerol-loaded TPGS/PEG-PCL micelles (6-GTPMs) were characterized based on particle size, polydispersity index (PDI), zeta potential, encapsulation efficiency (EE), drug loading (DL) and in vitro release profile. The pharmacokinetics and tissue distribution studies were also evaluated. The nanoformulation produced a particle size of 73.24 ± 2.84 nm with acceptable PDI (0.129 ± 0.03), zeta potential (−2.74 ± 0.92 mV), DL (4.64%) and EE (79.68%). The in vitro release profile showed that the 6-GTPMs enhanced the solubility of 6-Gingerol, while the pharmaceutical analysis in rats indicated that 6-GTPMs significantly improved the oral bioavailability of 6-Gingerol (about 3 folds) in circulation. The 6-GTPMs exhibited remarkable brain targetability in the tissue distribution analysis. Collectively, a 6-Gingerol polymeric micelle with enhanced oral bioavailability coupled with excellent brain distribution was successfully developed.

High Toughness Induced by Wormlike-Nanostructure in Epoxy Thermoset Containing Amphiphilic PDMS–PCL Block Copolymers

Muxuan Li,Zhengguang Heng,Yang Chen,Huawei Zou,Mei Liang

The modification of epoxy composites through the construction of nanostructures via self-organization of block copolymers has become a hot topic. In this research, high toughness epoxy thermoset was prepared through constructing wormlike-nanostructure by incorporating amphiphilic polydimethylsiloxane-block-poly(ε-caprolactone) block copolymer. The fracture toughness of subsequent epoxy thermosets increased nearly 355% comparing with neat epoxy with the addition of 40 wt % wormlike nanostructure, which was higher than that of thermosets with spherical nanostructure (142%). There was obviously plastic deformation in fractured surfaces of thermosets with wormlike nanostructure, it is believed that a combination of several toughening mechanisms leads to the improvement in fracture toughness. The morphologies transition, dynamic mechanical properties and wetting behavior of the thermoset containing spherical/wormlike nanostructures are also reported.

Folic acid-functionalized AIE Pdots based on amphiphilic PCL-b-PEG for targeted cell imaging

Yan Zhang,Yujue Chen,Xing Li,Jibo Zhang,Jinlong Chen,Bin Xu,Xueqi Fu,Wenjing Tian

Fluorescent block amphiphilic copolymers are one of the most important bioimaging materials which are highly desirable for early stage cancer diagnosis and treatment. However, sometimes the application of the fluorescent block copolymers is severely limited because of the aggregation-caused quenching (ACQ) effect. In this study, new aggregation induced emission polymer dots (AIE Pdots) were prepared through a self-assembly process by using an AIE-conjugated block copolymer containing an AIE fluorophore, 9,10-bis(4-hydroxystyryl)anthracene, hydrophobic poly(ε-caprolactone) segments, hydrophilic poly(ethylene glycol) segments and folate groups. The AIE Pdots are monodispersed in H2O with an average diameter of 15 nm, and possess strong emission and high solid state fluorescence quantum efficiency (Φ = 27.0%). Furthermore, the AIE Pdots show good stability and little toxicity to living cells and thus can be utilized for targeted HeLa cell imaging. Biological imaging investigation indicated that the folic acid functionalized AIE Pdots can be applied for targeted HeLa intracellular imaging.

Gambogic acid-loaded PEG–PCL nanoparticles act as an effective antitumor agent against gastric cancer

Dinghu Zhang,Zhengyun Zou,Wei Ren,Hanqing Qian,Qianfeng Cheng,Liulian Ji,Baorui Liu,Qin Liu

PCL nanofibrous incorporating unique matrix fusion protein adsorbed mesoporous bioactive glass for bone tissue engineering

Jiayu Lin,Long Liu,Shan Huang,Weijia Zheng,Haoming Liu,Zhenzu Bai,Kai Jiang,Xiaoyan Wang

Mesoporous bioactive glass (MBG) is a potential biomedical material in bone defect repairment because of its bioactivity, biocompatibility, and osteoinduction properties. Here we report that Mg-doped MBG scaffold with 3:1 Ca/Mg ratio (MBG-Ca/Mg-3) is good for MC3T3-E1 osteoblast differentiation and mineralization. Mimicking bone extracellular matrix structure by electrospinning, we used MBG-Ca/Mg-3 adsorbed with Osteocalcin-Osteopontin-Biglycan (OOB), a new unique matrix fusion protein, to form [email protected] /Mg-3 scaffold, which has multifunctional ability in calvarial bone defect repairment in vivo . Intriguingly, we found that [email protected] /Mg-3 scaffold increases the expression of osteoblastic marker genes, including bone morphogenetic protein ( Bmp2 ), osteopontin ( Opn ), Osterix , Runx2 through activation of ERK1/2. We concluded that [email protected] /Mg-3 scaffold promotes osteoblast differentiation and mineralization through ERK1/2 pathway and it can also enhance bone formation in vivo , which provides a new biomaterial in bone tissue engineering.

Dual antibacterial polypeptide-coated PCL@ZIF-8 nanofiber reduces infection and inflammation in burn wounds

Bai Xiao-Han,Zhang Jun,Cheng Guo-Ting,Liu Xiao-Fei,Sun Tian-Cai,Yang Jun,Cao Zhi-Kai,Ramakrishna Seeram,Long Yun-Ze

Burns on human skin often leads to slow recovery because of continuous wound infections caused by the loss of skin protection. In this study, a seed-free soaking method is put forward to prepare PCL@ZIF-8/εPL nanofibers as a dressing for burn wounds. This ZIF-8-coated polycaprolactone (PCL) fiber exhibits increased specific surface area, significantly increasing the polypeptide loading of epsilon polylysine (εPL) from 12 to 20 wt.%. The antibacterial experiment found that ZIF-8 and εPL exhibited dual antibacterial properties, and after εPL was loaded to ZIF-8, the nanofiber demonstrated stronger antibacterial properties that can better kill the remaining tenacious bacteria. This high-efficiency bactericidal property, combined with the ability to protect wounds from common infections by bacteria in the air, would promote wound healing, shortening the healing time period from 24 to 17 days. Further tissue sections confirm that the shielding effect and dual antibacterial properties of the composite fiber membrane are the reasons behind the acceleration of the healing of burns and scalds. Shielding and antibacterial material are helpful for the treatment of burns and scalds, and it may also guide the treatment of other types of wounds.

An effective thermal therapy against cancer using an E-jet 3D-printing method to prepare implantable magnetocaloric mats

Yikun Yang,Chunyi Tong,Juchang Zhong,Ruiying Huang,Weihong Tan,Zhikai Tan

Magnetic hyperthermia has been rapidly developed as a potential cancer treatment in recent years. Artificially induced hyperthermia close to a tumor can raise the temperature to 45°C causing tumor cell death. Herein, we introduce a novel method for rapid preparation of anti-cancer magnetocaloric PCL/Fe 3 O 4 mats capable of high-performance hyperthermia using E-jet 3D printing technology. Our 3D printed mats not only maintained the heating efficiency of traditional techniques for magnetic hyperthermia but also prolonged the effective therapy in vivo . When Fe 3 O 4 nanoparticles (NPs) were used in mats at a concentration of 6 mmol/L, 0.07 g PCL/Fe 3 O 4 mats were able to increase the temperature peripherally to 45°C under an alternating magnetic field (AMF) within 45 min. Moreover, the reproducibility experiment indicated that the maximum temperature was achieved following repeated heating and cooling cycles. Cell toxicity tests showed a high cell death rate during one treatment cycle. In vivo experiments indicated clear signs of tumor growth inhibitory and prolonged survival time of tumor-bearing mice after 4 weeks of treatment. The present magnetic mats may be a potential candidate for a novel heat-generating substrate for localized hyperthermia cancer therapy. Furthermore, the main advantage of such implantable magnetic mats is the local and precise delivery of Fe 3 O 4 NPs, ideal for the hyperthermia treatment of easily accessible tumors. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1827–1841, 2018.

Simultaneous Enhancement of Ductility and Impact Toughness in Biodegradable PLA/PCL Blends via a Plasticizer Strategy

Junrui Duan,Yuesheng Zhang,Zhiguo Hu,Hongtao Lu,Jianna Bao

Although blending brittle polylactide (PLA) with flexible poly(ε-caprolactone) (PCL) holds promise for developing biodegradable materials with tunable mechanical properties, their poor compatibility poses a significant challenge to effective toughening. In this study, PLA/PCL blends with varying Dibutyl itaconate (DBI) content were prepared via melt blending, and the effects of DBI loading on the properties of the blends were systematically investigated. The results demonstrated that the incorporation of DBI enhanced the intermolecular interactions between PLA and PCL chains, thereby improving their compatibility. The phase interface between the PLA matrix and the PCL dispersed phase became so progressively blurred with increasing DBI content that it was nearly indistinguishable at a loading of 7 phr, demonstrating a significant improvement in compatibility. With the increase in DBI content, both the elongation at break and impact strength of the blends exhibited a trend of initial increase followed by a decrease. At the optimal loading, the maximum values reached 314.3% and 29.5 kJ/m 2 , representing enhancements of 3.4-fold and 4.9-fold, respectively, compared to those of the neat PLA/PCL blend. Simultaneously, the crystallization rate and enzymatic degradation rate of the blends increased continuously with higher DBI content. This study opens a new avenue for developing high-toughness PLA-based blend materials without compromising their biodegradability. Summary DBI enhanced both elongation at break and impact strength of PLA/PCL blends. The incorporation of DBI improved the compatibility between PLA and PCL. The crystallization capability of the modified blends was enhanced. The modified blends showed an increased degradation rate.

Hyperbranched PCL/PS Copolymer-Based Solid Polymer Electrolytes Enable Long Cycle Life of Lithium Metal Batteries

Wei Ye,Muhammad Zaheer,Lianwei Li,Jun Wang,Hongli Xu,Chaoyang Wang,Yonghong Deng

Solid polymer electrolytes (SPE) are of great importance for developing the next-generation all-solid-state lithium metal batteries, which are featured by their high safety and extraordinary energy density. Herein, by using the highly efficient azide-alkyne click chemistry, a series of long-subchain hyperbranched copolymers from various compositions of AB2 macromonomers of PCL-2N3 (polycaprolactone) and PS-2N3 (polystyrene) were synthesized and employed as SPE polymer host. Taking advantage of the hyperbranched structure, the crystallization of PCL was successfully suppressed, and endows the SPE with high ionic conductivity and high mechanical properties simultaneously. By doping with LiFSI, the SPEs thereof exhibit high ionic conductivity (1.59 × 10−4 S cm−1 at 80 °C), broad electrochemical stability window (>4.6 V) and high lithium-ion transference number (>0.40). The electrolyte film based on the HB-II (the hyperbranched PCL/PS copolymer with 70 wt% PCL and 30 wt% PS) shows an ionic conductivity of 1.36 × 10−5 S·cm−1 at 80 °C and a high lithium transference number of 0.49. The all-solid-state LiFePO4//Li cell with HB-II-based SPE delivers a high and stable discharge capacity (133 mAh·g−1 at 1 C, with 90% capacity retention after 300 cycles) and exhibits long lifetime up to over 1200 cycles, owing to its relatively high ionic conductivity and good interfacial stability.

Electrospun PCL/mupirocin and chitosan/lidocaine hydrochloride multifunctional double layer nanofibrous scaffolds for wound dressing applications

Xiaoming Li,Chao Wang,Shuang Yang,Ping Liu,Bo Zhang

Background An ideal wound dressing should exhibit good biocompatibility, minimize pain and infection, absorb excess exudates, and maintain a moist environment. However, few clinical products meet all these needs. Therefore, the aim of this study was to fabricate a multifunctional double layer nanofibrous scaffolds (DLS) as a potential material for wound dressing. Materials and methods The scaffold was formed from mupirocin and lidocaine hydrochloride homogeneously incorporated into polycaprolactone as the first layer of scaffolds and chitosan as the second layer of scaffolds nanofibers through electrospinning. The fabricated nanofibrous scaffolds were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and measurement of swelling ratio, contact angle, drug release, and mechanical properties. Furthermore, antibacterial assessment, live/dead cell assays, and MTT assays were used to investigate the antibacterial activity and cytotoxicity of the nanofibrous scaffolds. Results The morphology of the nanofibrous scaffolds was studied by scanning electron microscopy, showing successful nanofibrous scaffolds. Fourier transform infrared spectroscopy demonstrated the successful incorporation of the material used to produce the produced nanofibrous scaffolds. Thermal studies with thermogravimetric analysis and differential scanning calorimetry indicated that the DLS had high thermal stability. The DLS also showed good in vitro characteristics in terms of improved swelling ratio and contact angle. The mechanical results revealed that the DLS had an improved tensile strength of 3.88 MPa compared with the second layer of scaffold (2.81 MPa). The release of drugs from the scaffold showed different profiles for the two drugs. Lidocaine hydrochlo ride exhibited an initial burst release (66% release within an hour); however, mupirocin exhibited only a 5% release. Furthermore, the DLS nanofibers displayed highly effective antibacterial activities against Staphylococcus aureus, Escherichia coli , and Pseudomonas aeruginosa and were nontoxic to fibroblasts. Conclusion The fabricated DLS exhibited excellent hydrophilicity, cytocompatibility, sustained drug release, and antibacterial activity, which are favorable qualities for its use as a multifunctional material for wound dressing applications.

Evaluation of Remodeling and Regeneration of Electrospun PLGA@PCL/Elastin Small-Diameter Vascular Grafts In Vivo

Yonghao Xiao,Yuanguo Zhang,Yuehao Xing,Ming Gao,Yuting Ge,Hailei Li,Xin Wu,Lin Ye,Zeng-guo Feng

Bypass vascular grafting is an effective treatment for cardiovascular disease. Currently, small-diameter vascular grafts (SDVGs, inner diameter <6 mm) for peripheral revascularization, especially for lower limb revascularization, are in high demand. Previously, we prepared and investigated PLGA@PCL SDVGs with core/shell fibers. In this study, PLGA@PCL/elastin core/shell fibers (PCEs) SDVGs were further prepared by electrospinning, so as to enhance the vascular regeneration performance through the introduction of exogenous soluble elastin. The cross-linking effects of elastin with different cross-linking reagents on PCEs SDVGs were subsequently explored. Among them, PCEs SDVGs cross-linked with 1-ethyl-3-(3-(dimethylamino)propyl) carbodiimide (EDCI) and N-hydroxysuccinimide (NHS) retained the most soluble elastin content and achieved a compliance of 1.74 ± 0.62%/mmHg × 10–2, a bursting pressure of 1750 mmHg, and a tensile strength of 2.09 ± 0.51 MPa, which are mostly close to those of human saphenous vein. Subsequently, in vivo transplantation in the abdominal aorta showed that all implanted SDVGs cross-linked by EDC/NHS (PCEsEN) remained patent without aneurysm formation. Histological staining results further showed that the introduction of elastin not only promoted the degradation of SDVGs but also accelerated the formation of neointimal tissue and suppressed the calcification. Thus, PCEsEN shows promising potential to be translated into SDVGs in clinic.