Fabricating macroscale smart actuators that can convert light energy into other forms of energy,especially mechanical and electrical energy,is of great significance.Herein,a simple and efficient 4D printed method for ...Fabricating macroscale smart actuators that can convert light energy into other forms of energy,especially mechanical and electrical energy,is of great significance.Herein,a simple and efficient 4D printed method for fabricating photomechanical actuators based on micro/nano-scale crystals is developed.The high versatility and generality of this method are successfully demonstrated using nine different types of photoresponsive crystalline actuators,including acylhydrazone-,anthracene-,olefin-,and azobenzene-based molecular crystals and covalent organic frameworks(COFs).The low-cost neutral silicone sealant elastomer is first chosen as the photomechanical 4D printing matrix.Notably,these actuators can be used to perform bionic motions(the first windmills spin using crystalline material,dragonflies fly,and sunflowers bloom)under the stimulation of visible light and can realize energy conversion from mechanical energy into electricity when coupled with a piezoelectric membrane.This work provides new insights into the design and manufacturing of smart photomechanical actuators and electricity generators and expands the application scope of COFs.展开更多
Melt electrowriting(MEW) enables the precise deposition of polymeric fibers at micro-/nanoscale, allowing for the fabrication of 3D biomimetic scaffolds. By incorporating stimuli-responsive polymers and/or functional ...Melt electrowriting(MEW) enables the precise deposition of polymeric fibers at micro-/nanoscale, allowing for the fabrication of 3D biomimetic scaffolds. By incorporating stimuli-responsive polymers and/or functional fillers, MEW-based 4D printing creates scaffolds capable of undergoing controlled, reversible shape transformations in response to external stimuli over time. These dynamic 4D scaffolds can be tailored for minimally invasive delivery, remote actuation, and real-time responsiveness to physiological environments, making them highly relevant for biomedical applications. This review systematically elucidates the principles of MEW-based 4D printing, including material considerations, actuation methods, and structure design strategies, along with shape programming and morphing mechanisms. The versatility of MEW for rational fabrication of biomimetic scaffolds is firstly introduced. Subsequently, the critical elements underpinning MEW-based 4D printing process are overviewed, including an analysis of stimuli-responsive materials compatible with MEW, an evaluation of applicable external stimuli, and a discussion on the advancements in design strategies for 4D scaffolds. Recent progress of MEW 4D scaffolds for applications in tissue engineering, biomedical implants, and drug delivery systems are highlighted. Finally, key challenges and perspectives toward material innovation, fabrication optimization, and actuation control are discussed. This review aims to provide valuable insights for design and creation of multifunctional biomimetic dynamic scaffolds by MEW-based 4D printing.展开更多
原发性高血压(essential hypertension,EH)主要特征为循环动脉血压增高,伴有器官功能损害^([1])。EH发病率逐年上升,并有年轻化趋势^([2])。长期持续的高血压会造成心脏和血管等发生改变,其中左心室肥厚为常见并发症,会导致心律失常、...原发性高血压(essential hypertension,EH)主要特征为循环动脉血压增高,伴有器官功能损害^([1])。EH发病率逐年上升,并有年轻化趋势^([2])。长期持续的高血压会造成心脏和血管等发生改变,其中左心室肥厚为常见并发症,会导致心律失常、心肌梗死等,严重威胁患者的生命健康^([3-4])。因此寻找早期评估左心室肥厚的指标可有效改善患者病情。分泌型卷曲相关蛋白2(secreted frizzled-related protein 2,SFRP2)作为Wnt结合蛋白家族的一员,可通过双向调控Wnt等通路调控心肌纤维化、心肌肥大^([5-6])。可溶性信号素4D(soluble signalling element 4D,sSema4D)参与心房颤动、冠心病以及高血压等疾病的进展^([7-8])。本研究旨在探讨EH患者血清SFRP2、sSema4D水平与左心室肥厚的关系。展开更多
基金the National Natural Science Foundation of China(22175099,22205116,22301147)National Key Research and Development Program of China(2021YFC2102100)+1 种基金Frontiers Science Center for New Organic Matter of Nankai University(63181206)111 Project(B12015).
文摘Fabricating macroscale smart actuators that can convert light energy into other forms of energy,especially mechanical and electrical energy,is of great significance.Herein,a simple and efficient 4D printed method for fabricating photomechanical actuators based on micro/nano-scale crystals is developed.The high versatility and generality of this method are successfully demonstrated using nine different types of photoresponsive crystalline actuators,including acylhydrazone-,anthracene-,olefin-,and azobenzene-based molecular crystals and covalent organic frameworks(COFs).The low-cost neutral silicone sealant elastomer is first chosen as the photomechanical 4D printing matrix.Notably,these actuators can be used to perform bionic motions(the first windmills spin using crystalline material,dragonflies fly,and sunflowers bloom)under the stimulation of visible light and can realize energy conversion from mechanical energy into electricity when coupled with a piezoelectric membrane.This work provides new insights into the design and manufacturing of smart photomechanical actuators and electricity generators and expands the application scope of COFs.
基金financially supported by the National Natural Science Foundation of China (Grant No. 1230242212572342)+2 种基金Marie Sklodowska-Curie grant agreement ENSIGN (101086226)Nano Ram (101120146)L4DNANO (101086227)
文摘Melt electrowriting(MEW) enables the precise deposition of polymeric fibers at micro-/nanoscale, allowing for the fabrication of 3D biomimetic scaffolds. By incorporating stimuli-responsive polymers and/or functional fillers, MEW-based 4D printing creates scaffolds capable of undergoing controlled, reversible shape transformations in response to external stimuli over time. These dynamic 4D scaffolds can be tailored for minimally invasive delivery, remote actuation, and real-time responsiveness to physiological environments, making them highly relevant for biomedical applications. This review systematically elucidates the principles of MEW-based 4D printing, including material considerations, actuation methods, and structure design strategies, along with shape programming and morphing mechanisms. The versatility of MEW for rational fabrication of biomimetic scaffolds is firstly introduced. Subsequently, the critical elements underpinning MEW-based 4D printing process are overviewed, including an analysis of stimuli-responsive materials compatible with MEW, an evaluation of applicable external stimuli, and a discussion on the advancements in design strategies for 4D scaffolds. Recent progress of MEW 4D scaffolds for applications in tissue engineering, biomedical implants, and drug delivery systems are highlighted. Finally, key challenges and perspectives toward material innovation, fabrication optimization, and actuation control are discussed. This review aims to provide valuable insights for design and creation of multifunctional biomimetic dynamic scaffolds by MEW-based 4D printing.
文摘原发性高血压(essential hypertension,EH)主要特征为循环动脉血压增高,伴有器官功能损害^([1])。EH发病率逐年上升,并有年轻化趋势^([2])。长期持续的高血压会造成心脏和血管等发生改变,其中左心室肥厚为常见并发症,会导致心律失常、心肌梗死等,严重威胁患者的生命健康^([3-4])。因此寻找早期评估左心室肥厚的指标可有效改善患者病情。分泌型卷曲相关蛋白2(secreted frizzled-related protein 2,SFRP2)作为Wnt结合蛋白家族的一员,可通过双向调控Wnt等通路调控心肌纤维化、心肌肥大^([5-6])。可溶性信号素4D(soluble signalling element 4D,sSema4D)参与心房颤动、冠心病以及高血压等疾病的进展^([7-8])。本研究旨在探讨EH患者血清SFRP2、sSema4D水平与左心室肥厚的关系。
