Healthcare‐acquired bacterial infections are a threat to public health. Therefore, development of self‐sterilizing implantable dressing materials is in increasing demand. Herein, a series of ...quaternized triblock copolymers, namely, QP‐b‐PCL‐b‐QPs, are synthesized and self‐assembled into reverse micelles (RMs) in tetrahydrofuran. The RMs contain biocompatible poly(ε‐caprolactone) (PCL) blocks in the shell to render biosafety and responsiveness, and biocidal quaternary blocks in the core to render antibacterial activity. In the presence of bacterial lipase, the biodegradable PCL blocks are hydrolyzed, resulting in the responsive release of quaternary biocidal agents (QBAs) to enable self‐sterilization. The RMs can be facilely impregnated into commercial gelatin sponge (GS) to fabricate RM2‐coated GS, which impose potent antibacterial activity in the presence of lipase. Compared to Gram‐negative P. aeruginosa, the Gram‐positive S. aureus and B. subtilis are more susceptible to QBAs released from RM2‐coated GS. The in vivo antibacterial assays and histological analyses further confirm the validity of RM2‐coated GS in reducing bacterial infection in mice model. These results, taken together, provide a promising strategy for the development of bioswitchable self‐sterilizing dressing materials to reduce healthcare‐acquired bacterial infections.
Quaternized triblock copolymers are synthesized and self‐assembled into reverse micelles that can be facilely impregnated into a commercial gelatin sponge to fabricate bioswitchable antibacterial dressings. Triggered by bacterial lipase, the dressings are able to release quaternary biocidal agents to kill bacteria at the vicinity and alleviate inflammatory response at the bacterial infection site.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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•A macroporous PBAT/PLGA foam was prepared using supercritical CO2.•The foam displayed suitable mechanical property for the fallopian tube stent.•A rapid biodegradation rate was ...observed in simulated internal environment.•Implantation in the fallopian tube verified good biocompatibility of the foam.
Tubal pregnancy is a common abnormal pregnancy manifestation, and the ordinary conservative treatment of tubal adhesion usually leads to the rupture of fallopian tube, which increases the risk of a second ectopic pregnancy. To avoid this symptom, it is suitable to implant a stent to separate the adhesion. Here we prepared the PBAT/PLGA foam as the stent material using supercritical CO2 foaming technology. With uniform macroporous structure and thin-wall feature, the foam possessed low compressive modulus in prevention of the possible second injury to the fallopian tube. The introduction of PLGA 50/50 improved the biodegradable capability of the foam, with a mass loss about 20% after a 12-week hydrolysis. After implanted into the ruptured fallopian tube of the rabbit model, the foam displayed excellent biocompatibility, and provided a good support to prevent tubal adhesion. As such, this work provides the foam material as a promising candidate for fallopian tube stent to remedy the tubal adhesion.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
PETG/PC/TPU polymer blend was prepared by mechanical blending. The mechanical properties of modified PETG/PC/TPU blend were characterized using a universal testing machine, and results were compared ...against two commercial thermoplastic products —Erkodur and Biolon. Blending modification improved the properties of PETG/PC/TPU. When blending ratio (wt%) was 70/10/20, PETG/PC/TPU exhibited optimal mechanical properties which exceeded those of Erkodur and Biolon. Tear strength was 50.23 MPa and elongation at break was 155.99%. Stress relaxation rate was 0.0136 N/s after 1 hour, which was significantly slower than Erkodur and Biolon (p<0.05). Water absorption rate was 0.57% after 2 weeks, which was significantly lower than Erkodur and Biolon (p<0.05).
Additive manufacturing (AM) demonstrates benefits in the high-precision production of devices with complicated structures, and the modification of materials for AM is an urgent need. To solve the ...bacterial infection of medical devices in their daily application, dimethyl octyl aminoethyl ammonium bromide (octyl-QDED), an organic antibacterial agent, was synthesized via the quaternary ammonium reaction. Then, the synthesized octyl-QDED was blended with acrylonitrile butadiene styrene (ABS) through the melt extrusion process to prepare antibacterial composite filaments for fused deposition modeling (FDM). The entire preparation processes were convenient and controllable. Characterizations of the structure and thermal stability of octyl-QDED confirmed its successful synthesis and application in the subsequent processes. The introduced maleic acid in the blending process acted as a compatibilizer, which improved the compatibility between the two phases. Characterizations of the rheological and mechanical properties proved that the addition of octyl-QDED made a slight difference to the comprehensive performance of the ABS matrix. When the content of octyl-QDED reached 3 phr, the composites showed excellent antibacterial properties. The prepared antibacterial composite filaments for FDM demonstrated great potential in medical and surgical areas.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Developing eco-friendly polymeric plasticizers with excellent migration resistance is one of the research hotspots in the polyvinyl chloride (PVC) industry. A low-molecular-weight biobased polyester ...rubber (LMW-BPR) was synthesized from five biobased polyester monomers in a 100-L reactor and evaluated as a potential eco-friendly polymeric plasticizer for PVC. The obtained LMW-BPR is an amorphous polyester material with a low glass transition temperature of −48°C and a molecular weight of 22 kg/mol, which is lower than that of existing polyester rubber but higher than those of most polyester plasticizer commodities. Plasticized PVC composites with a total plasticizer content of 50 phr were prepared by using the mixture of LMW-BPR and di-isononyl cyclohexane-1,2-dicarboxylate (DINCH, an eco-friendly monomeric plasticizer commodity) as the plasticizer. The migration resistance test showed that the migration loss of plasticizer in plasticized PVC composite decreased significantly with the increase of LMW-BPR content. When the content of LMW-BPR reaches 30 phr, the plasticized PVC composites are almost nonmigratory. In addition, compared with PVC composite plasticized by pure DINCH, co-plasticized PVC composites containing LMW-BPR exhibit higher tensile strength and thermal stability, and their flexibility, low-temperature resistance and biocompatibility are also maintained at a similar level to the former. Overall, LMW-BPR is an effective eco-friendly polymeric plasticizer for PVC and also sustainable and scalable, thus it is worthy of wide application.
Fused deposition modelling (FDM) is a commonly used 3D printing technology. The development of FDM materials was essential for the product quality of FDM. In this work, a series of polycaprolactone ...(PCL)-based composites for low-temperature FDM were developed. By melt blending technique, different ratios of starch were added into PCL to improve the performances of FDM, and the printability, tensile strength, rheological properties, crystallization behaviors and biological performances of the composites were studied. The PCL/starch composite had the best performance in FDM process with the starch ratio of 9 ph at 80–90 °C. The melting strength and solidification rate of PCL/starch composites were improved. The starch also increased the crystallization temperature, degree of crystallinity and crystallization rate of PCL/starch composites, while had no negative effects on the tensile strength of PCL. Due to the low printing temperature, various kinds of bioactive components were added into PCL/starch composites for preparation of antibacterial and biocompatible materials for FDM. The present work provides a new method to develop novel low-temperature FDM materials with various functions.
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•PCL/starch composites for low-temperature fused deposition modelling were developed.•The tensile strength, rheological properties and crystallization behaviors of PCL/starch composites were studied.•Bioactive components were added to functionalize the composites with antibacterial and biocompatible properties.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Antibacterial materials that prevent bacterial infections and mitigate bacterial virulence have attracted great scientific interests. In recent decades, the bactericidal polymers have been presented ...as promising candidates to combat bacterial pathogens, mainly based on the construction of bactericidal cationic polymers, functionalization with biocidal agents, and formation of bacterial‐repelling layers. However, these established strategies have inherent disadvantages because they often overlook important features such as their biocompatibility and biosafety, especially for biomedical applications. In recent years, many efforts have been made focusing on the development of multifunctional antibacterial materials to meet the elaborate requirements for medical devices and public hygiene products. Herein the recent advances in developing multifunctional materials for their antibacterial activities together with other functions including “kill‐and‐release” capability, hemocompatibility, cell proliferation promoting properties, and coagulation promoting ability for wound dressing are highlighted. In addition, the outlooks on the remaining challenges that should be addressed in the field of multifunctional antibacterial materials are also described.
The recent advances in the field of multifunctional antibacterial materials are summarized, which shed light on the manufacturing of next‐generation implantable or indwelling medical devices with antibacterial properties.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
CNTs/PAN nanofibers were electrospun from PAN-based solution for the preparation of carbon nanofiber composites. The as-spun polyacrylonitrile-based nanofibers were hot-stretched by weighing metal in ...a temperature controlled oven. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the morphology of the nanofibers, which indicated that carbon nanotubes were dispersed well in the composites and were completely wrapped by PAN matrix. Because of the strong interfacial interaction between CNTs and PAN, the CNTs/PAN application performance will be enhanced correspondingly, such as the mechanical properties and the electrical conductivity. It was concluded that the hot-stretched CNTs/PAN nanofibers can be used as a potential precursor to produce high-performance carbon composites.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Catheter-related infection is a great challenge to modern medicine, which causes significant economic burden and increases patient morbidity. Hence, there is a great requirement for functionalized ...surfaces with inherently antibacterial properties and biocompatibility that prevent bacterial colonization and attachment of blood cells. Herein, we developed a strategy for constructing polymer brushes with hierarchical architecture on polyurethane (PU) via surface-initiated atom-transfer radical polymerization (SI-ATRP). Surface-functionalized PU (PU-DMH) was readily prepared, which comprised of poly(3-dimethyl-2-(2-methylprop-2-enoyloxy)ethylazaniumylpropane-1-sulfonate) (PDMAPS) brushes as the lower layer and antimicrobial peptide-conjugated poly(methacrylic acid) (PMAA) brushes as the upper layer. The PU-DMH surface showed excellent bactericidal property against both Gram-positive and Gram-negative bacteria and could prevent accumulation of bacterial debris on surfaces. Simultaneously, the PU-DMH samples possessed good hemocompatibility and low cytotoxicity. Furthermore, the integrated antifouling and bactericidal properties of PU-DMH under hydrodynamic conditions were confirmed by an in vitro circulating model. The functionalized surface possessed persistent antifouling and bactericidal performances both under static and hydrodynamic conditions. The microbiological and histological results of animal experiments also verified the in vivo anti-infection performance. The present work might find promising clinical applications for preventing catheter-related infection.
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IJS, KILJ, NUK, PNG, UL, UM
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