Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug deliv...Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.展开更多
The orientation of the biological molecule immobi-lized on a solid surface has been critical in devel-opment of various applications. In this study, ori-entation of antibody was retained by protecting the antigen-bind...The orientation of the biological molecule immobi-lized on a solid surface has been critical in devel-opment of various applications. In this study, ori-entation of antibody was retained by protecting the antigen-binding site of the antibody prior to immo-bilization to -functionalized mixed self-assembled monolayer (SAM) of 12-mercaptododecanoic acid and 1-heptanethiol. More importantly, the number of immobilization bonds formed between each an-tigen-binding site protected antibody molecule and the solid surface was controlled by optimizing the mole fraction of the activated carboxyl group of the linker molecules in the mixed SAM. The amount of antibody used in this study was approximately equivalent to the amount for one monolayer surface coverage. The resulting activity of protected immo-bilized antibody was about 10 fold higher than that of random immobilized展开更多
Mimetic enzymes are devised as alternates or supplements of natural enzymes in broad fields but regulating their activities in a switchable manner remains challenging.Herein,we proposed an enzymatic self-assembly/disa...Mimetic enzymes are devised as alternates or supplements of natural enzymes in broad fields but regulating their activities in a switchable manner remains challenging.Herein,we proposed an enzymatic self-assembly/disassembly strategy to address this issue.A peptide molecule Nap FFEYIH(YH) was rationally designed which,after self-assembling into nanofibers,lined up the histidine moieties to form active hydrolysis centers for mimicking hydrolase activity.Enzymatic dephosphorylation of Nap FFEYp IH(Yp H) by alkaline phosphatase to yield YH also turned “ON” the hydrolase activity.In turn,phosphorylation of YH by phosphokinase epidermal growth factor receptor to yield Yp H disassembled the nanofibers and thus turned the activity “OFF”.As such,the “ON”/“OFF” of the mimetic hydrolase activities could be regulated under physiological conditions through ALP/EGFR-mediated self-assembly/disassembly of histidine nanofibers.This work provides a feasible strategy for the on-demand fabrication of artificial enzymes with controllable and superior activities.展开更多
Indomethacin has been encapsulated with polyelectrolyte multilayers for controlled release. Gelatin and alginate were alternatively deposited on indomethacin microcrystals. The released amount of indomethacin from coa...Indomethacin has been encapsulated with polyelectrolyte multilayers for controlled release. Gelatin and alginate were alternatively deposited on indomethacin microcrystals. The released amount of indomethacin from coated microcrystals in pH6. 8 phosphate buffer solution (PBS) was measured with a UV spectrophometer. The polyelectrolyte multilayer capsule thickness was proved to control the release rate. The effects of osmotic pressure existed during the release process of indomethacin from microcapsules coated by (gelatin/alginate) 4.展开更多
In the application of polymer gels to profile control and water shutoff,the gelation time will directly determine whether the gel can"go further"in the formation,but the most of the methods for delaying gel ...In the application of polymer gels to profile control and water shutoff,the gelation time will directly determine whether the gel can"go further"in the formation,but the most of the methods for delaying gel gelation time are complicated or have low responsiveness.There is an urgent need for an effective method for delaying gel gelation time with intelligent response.Inspired by the slow-release effect of drug capsules,this paper uses the self-assembly effect of gas-phase hydrophobic SiO_(2) in aqueous solution as a capsule to prepare an intelligent responsive self-assembled micro-nanocapsules.The capsule slowly releases the cross-linking agent under the stimulation of external conditions such as temperature and pH value,thus delaying gel gelation time.When the pH value is 2 and the concentration of gas-phase hydrophobic SiO_(2) particles is 10%,the gelation time of the capsule gel system at 30,60,90,and 120℃is12.5,13.2,15.2,and 21.1 times longer than that of the gel system without containing capsule,respectively.Compared with other methods,the yield stress of the gel without containing capsules was 78 Pa,and the yield stress after the addition of capsules was 322 Pa.The intelligent responsive self-assembled micronanocapsules prepared by gas-phase hydrophobic silica nanoparticles can not only delay the gel gelation time,but also increase the gel strength.The slow release of cross-linking agent from capsule provides an effective method for prolongating the gelation time of polymer gels.展开更多
Hydrolysis reactions are capable of directing the non-equilibrium assembly of biomolecular scaffolds to realize sophisticated structures and functions in natural systems.However,utilizing the proper hydrolysis reactio...Hydrolysis reactions are capable of directing the non-equilibrium assembly of biomolecular scaffolds to realize sophisticated structures and functions in natural systems.However,utilizing the proper hydrolysis reactions to construct controlled assemblies with complex topologies is still an arduous challenge in artificial systems and needs to be addressed.Herein,we report a nitric oxide(NO)-triggered slow hydrolysis strategy for the controlled construction of biomimetic supramolecular toroids(STs),thus realizing their visualization of intermediate structures and regulation of geometry parameters.This presented protocol harnesses hydrolysis reactions to control of non-equilibrium self-assembly processes for the construction of self-assemblies with complex topologies successfully,which sheds light on how the hydrolysis reaction rate can modulate the kinetic pathway of assembly,thus realizing the artificial establishment of bio-inspired hierarchical structures.展开更多
Biological stimuli-responsive polymers have increasingly attracted attention in recent years because it can satisfy many requirements of applications related with human body while traditional systems do not meet.Due t...Biological stimuli-responsive polymers have increasingly attracted attention in recent years because it can satisfy many requirements of applications related with human body while traditional systems do not meet.Due to the importance of this burgeoning field,great efforts have been devoted and,up to now,polymer chemists have made a remarkable success in this prospective research topic.In this review,we systematically generalize the present state of biological stimuli-responsive polymer systems.We highlight several representative examples to specify the current problems and look ahead a clear sense of direction in this area.展开更多
Nickel oxide(NiO)hollow microspheres with hierarchical structure were fabricated through a process consisting of a self-assembling,hydrothermal reaction and calcination.The prepared NiO hollow microspheres composed of...Nickel oxide(NiO)hollow microspheres with hierarchical structure were fabricated through a process consisting of a self-assembling,hydrothermal reaction and calcination.The prepared NiO hollow microspheres composed of many nanoflakes,are about 2-3μm in diameter.The length of the NiO flakes,having clear edges,is about 500-700 nm,while the thickness is only about 40-50 nm.This indicates that the NiO microspheres possess a hierarchical structure that can provide porous channels to facilitate the transmission of both electrons and electrolyte ions.NiO microspheres exhibit a high specific capacitance of about 1340 F/g at a current density of 1 A/g and high capacitance retention about 96.5%after 1000 cycles.What’s more,the conductive mechanism of nickel oxide for electrochemical capacitor electrodes was also studied.展开更多
Comprehensive Summary,Stimuli-controlled disassembly process has shown promise to direct delivery of probes and/or spatial-temporally control imaging signals for molecular imaging in vivo.Via the disassembly process,w...Comprehensive Summary,Stimuli-controlled disassembly process has shown promise to direct delivery of probes and/or spatial-temporally control imaging signals for molecular imaging in vivo.Via the disassembly process,well defined nanoprobes with a stimulus-responsive moiety can be controllably converted into small-molecular imaging agents in response to a stimulus,leading to a switch in imaging signals.Moreover,the on-site released small-molecule probes could enhance penetration into the deep tissue for improved imaging of deep-seated molecular targets.Therefore,such a stimuli-controllable disassembly approach has been widely utilized to build activatable molecular imaging probes for the noninvasive detection of various molecular targets in living subjects.In this review article,we first briefly introduce the general principle of stimuli-controlled disassembly.We then summarize the activatable probes based on different internal or external stimulus that has been utilized to control disassembly process.Activatable probes by using multiple stimuli to control cascaded in situ self-assembly and disassembly processes are also discussed.Finally,we close with a conclusion of current challenges and perspective in this field.展开更多
A set of amphiphilic poly(ethylene glycol)-b-poly(ethylene brassylate)(PEG-b-PEB) copolymers based on the PEB hydrophobic block was first synthesized by ring-opening polymerization of ethylene brassylate with an...A set of amphiphilic poly(ethylene glycol)-b-poly(ethylene brassylate)(PEG-b-PEB) copolymers based on the PEB hydrophobic block was first synthesized by ring-opening polymerization of ethylene brassylate with an organic catalyst. The EB/PEG molar ratios and reaction times were adjusted to achieve different chain lengths of PEB. Block copolymers that were characterized by1 H NMR and GPC could selfassemble into multimorphological aggregates in aqueous solution, which were characterized by DLS and TEM. The hydrophobic doxorubicin(DOX) was chosen as a drug model and successfully encapsulated into the nanoparticles. The release kinetics of DOX were investigated.展开更多
Nanoparticles conjugated with antibody were designed as active drug delivery system to reduce the toxicity and side effects of drugs for acute myeloid leukemia(AML).Moreover,methotrexate(MTX)was chosen as modeldru...Nanoparticles conjugated with antibody were designed as active drug delivery system to reduce the toxicity and side effects of drugs for acute myeloid leukemia(AML).Moreover,methotrexate(MTX)was chosen as modeldrug and encapsulate within folic acid modified carboxymethylchitosan(FACMCS)nanoparticles through self-assembling.The chemicalstructure,morphology,release and targeting of nanoparticles were characterized by routine detection.It is demonstrated that the mean diameter is about 150 nm,the release rate increases with the decreasing of p H,the binding rate of CD33 antibody and FA-CMCS nanoparticles is about 5:2,and nanoparticles can effectively bind onto HL60 cells in vitro.The experimentalresults indicate that the FA-CMCS nanoparticles conjugated with antibody may be used as a potentialp Hsensitive drug delivery system with leukemic targeting properties.展开更多
Tendon-bone interface injuries pose a significant challenge in tissue regeneration,necessitating innovative approaches.Hydrogels with integrated supportive features and controlled release of therapeutic agents have em...Tendon-bone interface injuries pose a significant challenge in tissue regeneration,necessitating innovative approaches.Hydrogels with integrated supportive features and controlled release of therapeutic agents have emerged as promising candidates for the treatment of such injuries.In this study,we aimed to develop a temperature-sensitive composite hydrogel capable of providing sustained release of magnesium ions(Mg^(2+)).We synthesized magnesium-Procyanidin coordinated metal polyphenol nanoparticles(Mg-PC)through a self-assembly process and integrated them into a two-component hydrogel.The hydrogel was composed of dopamine-modified hyaluronic acid(Dop-HA)and F127.To ensure controlled release and mitigate the“burst release”effect of Mg^(2+),we covalently crosslinked the Mg-PC nanoparticles through coordination bonds with the catechol moiety within the hydrogel.This crosslinking strategy extended the release window of Mg^(2+)concentrations for up to 56 days.The resulting hydrogel(Mg-PC@Dop-HA/F127)exhibited favorable properties,including injectability,thermosensitivity and shape adaptability,making it suitable for injection and adaptation to irregularly shaped supraspinatus implantation sites.Furthermore,the hydrogel sustained the release of Mg^(2+)and Procyanidins,which attracted mesenchymal stem and progenitor cells,alleviated inflammation,and promoted macrophage polarization towards the M2 phenotype.Additionally,it enhanced collagen synthesis and mineralization,facilitating the repair of the tendon-bone interface.By incorporating multilevel metal phenolic networks(MPN)to control ion release,these hybridized hydrogels can be customized for various biomedical applications.展开更多
The spontaneously generated electrical charge of a droplet dispensed from conventional pipetting is undesirable and unpredictable for most experiments that use pipetting.Hence,a method for controlling and removing the...The spontaneously generated electrical charge of a droplet dispensed from conventional pipetting is undesirable and unpredictable for most experiments that use pipetting.Hence,a method for controlling and removing the electrical charge needs to be developed.In this study,by using the electrode-deposited pipet tip(E-pipet tip),the charge-controlling system is newly developed and the electrical charge of a droplet is precisely controlled.The effect of electrolyte concentration and volume of the transferred solution to the electrical charge of a dispensed droplet is theoretically and experimentally investigated by using the equivalent capacitor model.Furthermore,a proof-of-concept example of the self-alignment and self-assembly of sequentially dispensed multiple droplets is demonstrated as one of the potential applications.Given that the electrical charge of the various aqueous droplets can be precisely and simply controlled,the fabricated E-pipet tip can be broadly utilized not only as a general charge-controlling platform of aqueous droplets but also as a powerful tool to explore fundamental scientific research regarding electrical charge of a droplet,such as the surface oscillation and evaporation of charged droplets.展开更多
The self-assembly monolayer (SAM) was prepared with 2-aminoethanethiol (AET) on the gold electrode. A new approach based on potential was first used to control DNA self-assembly covalently onto the SAM with the activa...The self-assembly monolayer (SAM) was prepared with 2-aminoethanethiol (AET) on the gold electrode. A new approach based on potential was first used to control DNA self-assembly covalently onto the SAM with the activation of l-ethyl-3(3-dimethylaminopropyl)-carbodiimide (EDC) and N-hydroxysulfosuccinimide (NHS). The influence of potential on DNA self-assembly was investigated by means of cyclic voltammetry (CV), AC impedance, Auger electron spectrometry (AES) and atomic force microscopy (AFM). The result proves that controlled potential can affect the course of DNA self-assembly. More negative potential can restrain the DNA self-assembly, while more positive potential can accelerate the DNA self-assembly, which is of great significance for the control of DNA self-assembly and will find wide application in the field of DNA-based devices.展开更多
This paper presents a self-assembly control strategy for the swarm modular robots. Simulated and physical experiments are conducted based on the Sambot platform, which is a novel self-assembly modular robot having the...This paper presents a self-assembly control strategy for the swarm modular robots. Simulated and physical experiments are conducted based on the Sambot platform, which is a novel self-assembly modular robot having the characteristics of both the chain-type and the mobile self-reconfigurable robots. Multiple Sambots can autonomously move and connect with one another through self-assembly to form robotic organisms. The configuration connection state table is used to describe the configuration of the robotic structure. A directional self-assembly control model is proposed to perform the self-assembly experiments. The self-assembly process begins with one Sambot as the seed, and then the Docking Sambots use a behavior-based controller to achieve connection with the seed Sambot. The controller is independent of the target configuration. The seed and connected Sambots execute a configuration comparison algorithm to control the growth of the robotic structure. Furthermore, the simul- taneous self-assembly of multiple Sambots is discussed. For multiple configurations, self-assembly experiments are conducted in simulation platform and physical platform of Sambot. The experimental results verify the effectiveness and scalability of the self-assembly algorithms.展开更多
Four-dimensional(4D)printing is a promising technology that provides solutions for compelling needs in various fields.Most of the reported 4D printed systems are based on the temporal shape transformation of printed s...Four-dimensional(4D)printing is a promising technology that provides solutions for compelling needs in various fields.Most of the reported 4D printed systems are based on the temporal shape transformation of printed subjects.Induction of temporal heterogenicity in functions in addition to shape may extend the scope of 4D printing.Herein,we report a 4D printing approach using plant protein(zein)gel inspired by the amyloid fibrils formation mechanism.The printing of zein gel in a specialized layered-Carbopol supporting bath with different water concentrations in an ethanol-water mixture modulates hydrophobic and hydrogen bonding that causes temporal changes in functions.The part of the construct printed in a supporting bath with higher water content exhibits higher drug loading,faster drug release and degradation than those printed in the supporting bath with lower water content.Tri-segment conduit and butterfly-shaped construct with two asymmetrical wings are printed using this system to evaluate biomedical function as nerve conduit and drug delivery system.4D printed conduits are also effective as a drug-eluting urethral stent in the porcine model.Overall,this study extends the concept of 4D printing beyond shape transformation and presents an approach of fabricating specialized baths for 4D printing that can also be extended to other materials to obtain 4D printed medical devices with translational potential.展开更多
基金supported by the Natural Science Foundation of Shandong Province,No.ZR2023MC168the National Natural Science Foundation of China,No.31670989the Key R&D Program of Shandong Province,No.2019GSF107037(all to CS).
文摘Vascular endothelial growth factor and its mimic peptide KLTWQELYQLKYKGI(QK)are widely used as the most potent angiogenic factors for the treatment of multiple ischemic diseases.However,conventional topical drug delivery often results in a burst release of the drug,leading to transient retention(inefficacy)and undesirable diffusion(toxicity)in vivo.Therefore,a drug delivery system that responds to changes in the microenvironment of tissue regeneration and controls vascular endothelial growth factor release is crucial to improve the treatment of ischemic stroke.Matrix metalloproteinase-2(MMP-2)is gradually upregulated after cerebral ischemia.Herein,vascular endothelial growth factor mimic peptide QK was self-assembled with MMP-2-cleaved peptide PLGLAG(TIMP)and customizable peptide amphiphilic(PA)molecules to construct nanofiber hydrogel PA-TIMP-QK.PA-TIMP-QK was found to control the delivery of QK by MMP-2 upregulation after cerebral ischemia/reperfusion and had a similar biological activity with vascular endothelial growth factor in vitro.The results indicated that PA-TIMP-QK promoted neuronal survival,restored local blood circulation,reduced blood-brain barrier permeability,and restored motor function.These findings suggest that the self-assembling nanofiber hydrogel PA-TIMP-QK may provide an intelligent drug delivery system that responds to the microenvironment and promotes regeneration and repair after cerebral ischemia/reperfusion injury.
文摘The orientation of the biological molecule immobi-lized on a solid surface has been critical in devel-opment of various applications. In this study, ori-entation of antibody was retained by protecting the antigen-binding site of the antibody prior to immo-bilization to -functionalized mixed self-assembled monolayer (SAM) of 12-mercaptododecanoic acid and 1-heptanethiol. More importantly, the number of immobilization bonds formed between each an-tigen-binding site protected antibody molecule and the solid surface was controlled by optimizing the mole fraction of the activated carboxyl group of the linker molecules in the mixed SAM. The amount of antibody used in this study was approximately equivalent to the amount for one monolayer surface coverage. The resulting activity of protected immo-bilized antibody was about 10 fold higher than that of random immobilized
基金supported by the National Natural Science Foundation of China (22234002,22204019,82172097)the Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX22_0245)。
文摘Mimetic enzymes are devised as alternates or supplements of natural enzymes in broad fields but regulating their activities in a switchable manner remains challenging.Herein,we proposed an enzymatic self-assembly/disassembly strategy to address this issue.A peptide molecule Nap FFEYIH(YH) was rationally designed which,after self-assembling into nanofibers,lined up the histidine moieties to form active hydrolysis centers for mimicking hydrolase activity.Enzymatic dephosphorylation of Nap FFEYp IH(Yp H) by alkaline phosphatase to yield YH also turned “ON” the hydrolase activity.In turn,phosphorylation of YH by phosphokinase epidermal growth factor receptor to yield Yp H disassembled the nanofibers and thus turned the activity “OFF”.As such,the “ON”/“OFF” of the mimetic hydrolase activities could be regulated under physiological conditions through ALP/EGFR-mediated self-assembly/disassembly of histidine nanofibers.This work provides a feasible strategy for the on-demand fabrication of artificial enzymes with controllable and superior activities.
基金The National Key Fundamental Research FundGrant number:9732003C8615700+1 种基金The National Natural Science Fund of ChinaGrant number:20376068
文摘Indomethacin has been encapsulated with polyelectrolyte multilayers for controlled release. Gelatin and alginate were alternatively deposited on indomethacin microcrystals. The released amount of indomethacin from coated microcrystals in pH6. 8 phosphate buffer solution (PBS) was measured with a UV spectrophometer. The polyelectrolyte multilayer capsule thickness was proved to control the release rate. The effects of osmotic pressure existed during the release process of indomethacin from microcapsules coated by (gelatin/alginate) 4.
基金support and funding from the National Natural Science Foundation of China (No.52174047)Sinopec Project (No.P21063-3)。
文摘In the application of polymer gels to profile control and water shutoff,the gelation time will directly determine whether the gel can"go further"in the formation,but the most of the methods for delaying gel gelation time are complicated or have low responsiveness.There is an urgent need for an effective method for delaying gel gelation time with intelligent response.Inspired by the slow-release effect of drug capsules,this paper uses the self-assembly effect of gas-phase hydrophobic SiO_(2) in aqueous solution as a capsule to prepare an intelligent responsive self-assembled micro-nanocapsules.The capsule slowly releases the cross-linking agent under the stimulation of external conditions such as temperature and pH value,thus delaying gel gelation time.When the pH value is 2 and the concentration of gas-phase hydrophobic SiO_(2) particles is 10%,the gelation time of the capsule gel system at 30,60,90,and 120℃is12.5,13.2,15.2,and 21.1 times longer than that of the gel system without containing capsule,respectively.Compared with other methods,the yield stress of the gel without containing capsules was 78 Pa,and the yield stress after the addition of capsules was 322 Pa.The intelligent responsive self-assembled micronanocapsules prepared by gas-phase hydrophobic silica nanoparticles can not only delay the gel gelation time,but also increase the gel strength.The slow release of cross-linking agent from capsule provides an effective method for prolongating the gelation time of polymer gels.
基金supported by the National Science Foundation of China(22071197,22022107,82304889)。
文摘Hydrolysis reactions are capable of directing the non-equilibrium assembly of biomolecular scaffolds to realize sophisticated structures and functions in natural systems.However,utilizing the proper hydrolysis reactions to construct controlled assemblies with complex topologies is still an arduous challenge in artificial systems and needs to be addressed.Herein,we report a nitric oxide(NO)-triggered slow hydrolysis strategy for the controlled construction of biomimetic supramolecular toroids(STs),thus realizing their visualization of intermediate structures and regulation of geometry parameters.This presented protocol harnesses hydrolysis reactions to control of non-equilibrium self-assembly processes for the construction of self-assemblies with complex topologies successfully,which sheds light on how the hydrolysis reaction rate can modulate the kinetic pathway of assembly,thus realizing the artificial establishment of bio-inspired hierarchical structures.
基金financially supported by the National Natural Science Foundation of China(Nos.21674022 and 51703034)
文摘Biological stimuli-responsive polymers have increasingly attracted attention in recent years because it can satisfy many requirements of applications related with human body while traditional systems do not meet.Due to the importance of this burgeoning field,great efforts have been devoted and,up to now,polymer chemists have made a remarkable success in this prospective research topic.In this review,we systematically generalize the present state of biological stimuli-responsive polymer systems.We highlight several representative examples to specify the current problems and look ahead a clear sense of direction in this area.
基金Project(51274248)supported by the National Natural Science Foundation of ChinaProject(201FA31440)supported by the International S&T Cooperation Program of China
文摘Nickel oxide(NiO)hollow microspheres with hierarchical structure were fabricated through a process consisting of a self-assembling,hydrothermal reaction and calcination.The prepared NiO hollow microspheres composed of many nanoflakes,are about 2-3μm in diameter.The length of the NiO flakes,having clear edges,is about 500-700 nm,while the thickness is only about 40-50 nm.This indicates that the NiO microspheres possess a hierarchical structure that can provide porous channels to facilitate the transmission of both electrons and electrolyte ions.NiO microspheres exhibit a high specific capacitance of about 1340 F/g at a current density of 1 A/g and high capacitance retention about 96.5%after 1000 cycles.What’s more,the conductive mechanism of nickel oxide for electrochemical capacitor electrodes was also studied.
基金the National Natural Science Foundation of China(22137003 and 21922406)Natural Science Foundation of Jiangsu Province(BK20200301 and BK20190055)the Fundamental Research Funds for the Central Universities(020514380251)are acknowledged.
文摘Comprehensive Summary,Stimuli-controlled disassembly process has shown promise to direct delivery of probes and/or spatial-temporally control imaging signals for molecular imaging in vivo.Via the disassembly process,well defined nanoprobes with a stimulus-responsive moiety can be controllably converted into small-molecular imaging agents in response to a stimulus,leading to a switch in imaging signals.Moreover,the on-site released small-molecule probes could enhance penetration into the deep tissue for improved imaging of deep-seated molecular targets.Therefore,such a stimuli-controllable disassembly approach has been widely utilized to build activatable molecular imaging probes for the noninvasive detection of various molecular targets in living subjects.In this review article,we first briefly introduce the general principle of stimuli-controlled disassembly.We then summarize the activatable probes based on different internal or external stimulus that has been utilized to control disassembly process.Activatable probes by using multiple stimuli to control cascaded in situ self-assembly and disassembly processes are also discussed.Finally,we close with a conclusion of current challenges and perspective in this field.
基金supported by the Open Fund of State Key Laboratory of Medicinal Chemical Biology (Nankai University) under grant 20140523the Fundamental Research Funds for the Central Universities (Nos. SWU 113075 and XDJK2014B015)
文摘A set of amphiphilic poly(ethylene glycol)-b-poly(ethylene brassylate)(PEG-b-PEB) copolymers based on the PEB hydrophobic block was first synthesized by ring-opening polymerization of ethylene brassylate with an organic catalyst. The EB/PEG molar ratios and reaction times were adjusted to achieve different chain lengths of PEB. Block copolymers that were characterized by1 H NMR and GPC could selfassemble into multimorphological aggregates in aqueous solution, which were characterized by DLS and TEM. The hydrophobic doxorubicin(DOX) was chosen as a drug model and successfully encapsulated into the nanoparticles. The release kinetics of DOX were investigated.
基金Funded by the National Natural Science Foundation of China(No.50973088)
文摘Nanoparticles conjugated with antibody were designed as active drug delivery system to reduce the toxicity and side effects of drugs for acute myeloid leukemia(AML).Moreover,methotrexate(MTX)was chosen as modeldrug and encapsulate within folic acid modified carboxymethylchitosan(FACMCS)nanoparticles through self-assembling.The chemicalstructure,morphology,release and targeting of nanoparticles were characterized by routine detection.It is demonstrated that the mean diameter is about 150 nm,the release rate increases with the decreasing of p H,the binding rate of CD33 antibody and FA-CMCS nanoparticles is about 5:2,and nanoparticles can effectively bind onto HL60 cells in vitro.The experimentalresults indicate that the FA-CMCS nanoparticles conjugated with antibody may be used as a potentialp Hsensitive drug delivery system with leukemic targeting properties.
基金supported by the National Natural Science Foundation of China[grant numbers:82302639,81974327,81974328 and 82372358]National Students’Platform for Innovation and Entrepreneurship Training Program of China[grant number:No.202212121004]+1 种基金Natural Science Funds for Distinguished Young Scholar of Guangdong province[grant number:2022B1515020044]the Natural Science Foundation of Guangdong Province[grant number:2022A1515011101].
文摘Tendon-bone interface injuries pose a significant challenge in tissue regeneration,necessitating innovative approaches.Hydrogels with integrated supportive features and controlled release of therapeutic agents have emerged as promising candidates for the treatment of such injuries.In this study,we aimed to develop a temperature-sensitive composite hydrogel capable of providing sustained release of magnesium ions(Mg^(2+)).We synthesized magnesium-Procyanidin coordinated metal polyphenol nanoparticles(Mg-PC)through a self-assembly process and integrated them into a two-component hydrogel.The hydrogel was composed of dopamine-modified hyaluronic acid(Dop-HA)and F127.To ensure controlled release and mitigate the“burst release”effect of Mg^(2+),we covalently crosslinked the Mg-PC nanoparticles through coordination bonds with the catechol moiety within the hydrogel.This crosslinking strategy extended the release window of Mg^(2+)concentrations for up to 56 days.The resulting hydrogel(Mg-PC@Dop-HA/F127)exhibited favorable properties,including injectability,thermosensitivity and shape adaptability,making it suitable for injection and adaptation to irregularly shaped supraspinatus implantation sites.Furthermore,the hydrogel sustained the release of Mg^(2+)and Procyanidins,which attracted mesenchymal stem and progenitor cells,alleviated inflammation,and promoted macrophage polarization towards the M2 phenotype.Additionally,it enhanced collagen synthesis and mineralization,facilitating the repair of the tendon-bone interface.By incorporating multilevel metal phenolic networks(MPN)to control ion release,these hybridized hydrogels can be customized for various biomedical applications.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIP).(No.2014R1A2A1A010065272011-0030075+1 种基金2012R1A2A2A06047424)supported by the convergence technology development program for bionic arm through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT&Future Planning(No.2014M3C1B2048632)
文摘The spontaneously generated electrical charge of a droplet dispensed from conventional pipetting is undesirable and unpredictable for most experiments that use pipetting.Hence,a method for controlling and removing the electrical charge needs to be developed.In this study,by using the electrode-deposited pipet tip(E-pipet tip),the charge-controlling system is newly developed and the electrical charge of a droplet is precisely controlled.The effect of electrolyte concentration and volume of the transferred solution to the electrical charge of a dispensed droplet is theoretically and experimentally investigated by using the equivalent capacitor model.Furthermore,a proof-of-concept example of the self-alignment and self-assembly of sequentially dispensed multiple droplets is demonstrated as one of the potential applications.Given that the electrical charge of the various aqueous droplets can be precisely and simply controlled,the fabricated E-pipet tip can be broadly utilized not only as a general charge-controlling platform of aqueous droplets but also as a powerful tool to explore fundamental scientific research regarding electrical charge of a droplet,such as the surface oscillation and evaporation of charged droplets.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 69890220 and 60171005) the Natural Science Foundation of Jiangsu Province (China) (Grant Nos. BK99006 and BK2001131)the Promotional Foundation of the Ministry of
文摘The self-assembly monolayer (SAM) was prepared with 2-aminoethanethiol (AET) on the gold electrode. A new approach based on potential was first used to control DNA self-assembly covalently onto the SAM with the activation of l-ethyl-3(3-dimethylaminopropyl)-carbodiimide (EDC) and N-hydroxysulfosuccinimide (NHS). The influence of potential on DNA self-assembly was investigated by means of cyclic voltammetry (CV), AC impedance, Auger electron spectrometry (AES) and atomic force microscopy (AFM). The result proves that controlled potential can affect the course of DNA self-assembly. More negative potential can restrain the DNA self-assembly, while more positive potential can accelerate the DNA self-assembly, which is of great significance for the control of DNA self-assembly and will find wide application in the field of DNA-based devices.
基金supported by the National High Technology Research and Development Program of China ("863" Program) (Grant Nos. 2009AA043901 and 2012AA041402)National Natural Science Foundation of China (Grant No. 61175079)+1 种基金Fundamental Research Funds for the Central Universities (Grant No. YWF-11-02-215)Beijing Technological New Star Project (Grant No. 2008A018)
文摘This paper presents a self-assembly control strategy for the swarm modular robots. Simulated and physical experiments are conducted based on the Sambot platform, which is a novel self-assembly modular robot having the characteristics of both the chain-type and the mobile self-reconfigurable robots. Multiple Sambots can autonomously move and connect with one another through self-assembly to form robotic organisms. The configuration connection state table is used to describe the configuration of the robotic structure. A directional self-assembly control model is proposed to perform the self-assembly experiments. The self-assembly process begins with one Sambot as the seed, and then the Docking Sambots use a behavior-based controller to achieve connection with the seed Sambot. The controller is independent of the target configuration. The seed and connected Sambots execute a configuration comparison algorithm to control the growth of the robotic structure. Furthermore, the simul- taneous self-assembly of multiple Sambots is discussed. For multiple configurations, self-assembly experiments are conducted in simulation platform and physical platform of Sambot. The experimental results verify the effectiveness and scalability of the self-assembly algorithms.
基金This study was supported by the National Key R&D Program of China(2019YFE0101200)the Science and Technology Commission Shanghai Municipality,China(13JC1403400,18490740200)+1 种基金the Foreign Young Talent Program from the Ministry of Science and Technology,China(QN2022134003L)the Plan of Jiaxing Innovation and Elites Leading,China.
文摘Four-dimensional(4D)printing is a promising technology that provides solutions for compelling needs in various fields.Most of the reported 4D printed systems are based on the temporal shape transformation of printed subjects.Induction of temporal heterogenicity in functions in addition to shape may extend the scope of 4D printing.Herein,we report a 4D printing approach using plant protein(zein)gel inspired by the amyloid fibrils formation mechanism.The printing of zein gel in a specialized layered-Carbopol supporting bath with different water concentrations in an ethanol-water mixture modulates hydrophobic and hydrogen bonding that causes temporal changes in functions.The part of the construct printed in a supporting bath with higher water content exhibits higher drug loading,faster drug release and degradation than those printed in the supporting bath with lower water content.Tri-segment conduit and butterfly-shaped construct with two asymmetrical wings are printed using this system to evaluate biomedical function as nerve conduit and drug delivery system.4D printed conduits are also effective as a drug-eluting urethral stent in the porcine model.Overall,this study extends the concept of 4D printing beyond shape transformation and presents an approach of fabricating specialized baths for 4D printing that can also be extended to other materials to obtain 4D printed medical devices with translational potential.