Shot and step response measurements were carried out with inert bed and adsorption bed both under iso-thermal conditions.Parameter values were determined from a time domain analysis of the measured inputand response s...Shot and step response measurements were carried out with inert bed and adsorption bed both under iso-thermal conditions.Parameter values were determined from a time domain analysis of the measured inputand response signal.Sensitivity test in the parameter values showed that shot response measurements maygive more reliable parameter values than step measurements.Since Kubin[1]and Kucera[2]proposed a parameter estimation technique based on a moment methodfor adsorption system,attention has been focused on dynamic input-output measurements with variouspacked bed systems for the parameter estimation.The object of this work is to compare shot and step re-sponse measurements and see which measurement gives more reliable parameter values.展开更多
The objective of this paper is to incorporate vehicle mix in stimulus-response car-following models. Separate models were estimated for acceleration and deceleration responses to account for vehicle mix via both movem...The objective of this paper is to incorporate vehicle mix in stimulus-response car-following models. Separate models were estimated for acceleration and deceleration responses to account for vehicle mix via both movement state and vehicle type. For each model, three submodels were developed for different pairs of following vehicles including "automobile following automobile," "automobile following truck," and "truck following automobile." The estimated model parameters were then validated against other data from a similar region and roadway. The results indicated that drivers' behaviors were significantly different among the different pairs of following vehicles. Also the magnitude of the estimated parameters depends on the type of vehicle being driven and/or followed. These results demonstrated the need to use separate models depending on movement state and vehicle type. The differences in parameter estimates confirmed in this paper highlight traffic safety and operational issues of mixed traffic operation on a single lane. The findings of this paper can assist transportation professionals to improve traffic simulation models used to evaluate the impact of different strategies on ameliorate safety and performance of highways. In addition, driver response time lag estimates can be used in roadway design to calculate important design parameters such as stopping sight distance on horizontal and vertical curves for both automobiles and trucks.展开更多
Diverse natural organisms possess stimulus-responsive structures to adapt to the surrounding environment.Inspired by nature,researchers have developed various smart stimulus-responsive structures with adjustable prope...Diverse natural organisms possess stimulus-responsive structures to adapt to the surrounding environment.Inspired by nature,researchers have developed various smart stimulus-responsive structures with adjustable properties and functions to address the demands of ever-changing application environments that are becoming more intricate.Among many fabrication methods for stimulus-responsive structures,femtosecond laser direct writing(FsLDW)has received increasing attention because of its high precision,simplicity,true three-dimensional machining ability,and wide applicability to almost all materials.This paper systematically outlines state-of-the-art research on stimulus-responsive structures prepared by FsLDW.Based on the introduction of femtosecond laser-matter interaction and mainstream FsLDW-based manufacturing strategies,different stimulating factors that can trigger structural responses of prepared intelligent structures,such as magnetic field,light,temperature,pH,and humidity,are emphatically summarized.Various applications of functional structures with stimuli-responsive dynamic behaviors fabricated by FsLDW,as well as the present obstacles and forthcoming development opportunities,are discussed.展开更多
AM-AMPS-TAC polymers with different charge distribution are synthesized using acrylamide(AM),2-acrylamido-2-methylpropanesulfonate(AMPS)and 3-acrylamidopropyl trimethylammonium(TAC)at different feed ratios by polymeri...AM-AMPS-TAC polymers with different charge distribution are synthesized using acrylamide(AM),2-acrylamido-2-methylpropanesulfonate(AMPS)and 3-acrylamidopropyl trimethylammonium(TAC)at different feed ratios by polymerization in solution.The salt-responsive behavior,reasons leading to salt-responsiveness,and effects of polymers molecular structure on salt-responsiveness are studied by laboratory experiments to find out the adaptability of the polymers.Rheology test under stepwise shear mode shows that the AM-AMPS-TAC polymers have salt responsiveness,and the closer the feeds of AMPS and ATC,the more significant the salt responsiveness will be.Conformation change of polymers molecular chain under salt stimulus is studied by turbidity test and micro-morphology analysis,and the responsive mechanism is further investigated by intrinsic viscosity test and copolymer composition analysis.Results indicate that the salt-responsive behavior of AM-AMPS-TAC polymers derives from the"curled to expanded"transition of chain conformation under salt stimulus,and this transition is led by the screening effect of salt which weakens polymers intramolecular ionic bond.Application in saturated saltwater drilling fluid shows that the AM90-AMPS5-TAC5 polymer has the best salt-tolerance and temperature-tolerance when used together with fluid loss controller PAC-Lv.The drilling fluid saturated with NaCl can maintain stable viscosity,good dispersion and low fluid loss for long time under 150℃.展开更多
Polymeric nanoparticles with unique properties are regarded as the most promising materials for biomedical applications including drug delivery and in vitro/in vivo imaging.Among them,stimulus-responsive polymeric nan...Polymeric nanoparticles with unique properties are regarded as the most promising materials for biomedical applications including drug delivery and in vitro/in vivo imaging.Among them,stimulus-responsive polymeric nanoparticles,usually termed as "intelligent" nanoparticles,could undergo structure,shape,and property changes after being exposed to external signals including pH,temperature,magnetic field,and light,which could be used to modulate the macroscopical behavior of the nanoparticles.This paper reviews the recent progress in stimulus-responsive nanoparticles used for drug delivery and in vitro/in vivo imaging,with an emphasis on double/multiple stimulus-responsive systems and their biomedical applications.展开更多
Luminogens that exhibit stimulus-responsive room temperature phosphorescence(RTP)have attracted significant attention for their applications in a wide range of fields such as data storage,sensors,and bio-imaging.Howev...Luminogens that exhibit stimulus-responsive room temperature phosphorescence(RTP)have attracted significant attention for their applications in a wide range of fields such as data storage,sensors,and bio-imaging.However,very few such materials are known,partly because of the unclear internal mechanism.In this review,we summarize recent advances in the field of stimulusresponsive RTP in purely organic luminogens,focusing on their unique emission behaviors and internal mechanisms governing the phenomena.We also attempt to identify the relationship between the mechanism,luminogens,and possible applications.展开更多
Circularly polarized luminescence(CPL)has gained considerable attention in various systems and has rapidly developed into an emerging research field.To meet the needs of actual applications in diverse fields,a high lu...Circularly polarized luminescence(CPL)has gained considerable attention in various systems and has rapidly developed into an emerging research field.To meet the needs of actual applications in diverse fields,a high luminescence dissymmetry factor(glum)and tunable optical performance of CPL would be the most urgent pursuit for researchers.Accordingly,many emerging CPL materials and various strategies have been developed to address these critical issues.Emissive cholesteric liquid crystals(CLCs),that is,luminescent self-organized helical superstructures,are considered to be ideal candidates for constructing CPL-active materials,as they not only exhibit high glum values,but also enable flexible optical control of CPL.This review mainly summarizes the characteristics of CPL based on CLCs as the bulk phase doped with different emitters,including aggregated induced emission molecules,conventional organic small molecules,polymer emitters,metal-organic complex emitters,and luminescent nanoparticles.In addition,the recent significant progress in stimulus-responsive CPL based on emissive CLCs in terms of several types of stimuli,including light,electricity,temperature,mechanical force,and multiple stimuli is presented.Finally,a short perspective on the opportunities and challenges associated with CPL-active materials based on the CLC field is provided.This review is anticipated to offer new insights and guidelines for developing CLC-based CPL-active materials for broader applications.展开更多
Solid-state materials that exhibit pressure stimulus-response characteristics in a manner of emission signal,known as piezochromic luminescence(PCL),demonstrate great potential in photoelectric devices.The weakened lu...Solid-state materials that exhibit pressure stimulus-response characteristics in a manner of emission signal,known as piezochromic luminescence(PCL),demonstrate great potential in photoelectric devices.The weakened luminescence and insignificant color change in the aggregation state,however,hampers their practical applications.Herein,a highly emissive coordination polymer,[Zn2(H4TTPE)(H2O)4]·H2O(CUST-805),is successfully constructed by employing an AIE-active chromophore as the building block.The structural characterization and photophysical properties are systematically studied.Owing to intrinsic twisted conformation and AIE feature of tetraphenylethylene-tetrazole ligand,CUST-805 achieves the visible and reversible PCL from blue to green switched by different external stimuli.The transformation between crystalline and amorphous states is proved to be the origin of present PCL behavior.Moreover,on basis of electron and energy transfer quenching mechanism,the highly selective and sensitive sensor based on CUST-805 is realized,showing the low detection limit of 0.29 ppm towards 2,4,6-trinitrophenol.展开更多
The development of smart drug delivery systems(SDDSs)based on engineered nanomaterials is important for clinical applications.Nevertheless,controllable administration of chemotherapeutic drugs for deep tumors and the ...The development of smart drug delivery systems(SDDSs)based on engineered nanomaterials is important for clinical applications.Nevertheless,controllable administration of chemotherapeutic drugs for deep tumors and the avoidance of side effects caused by off-targeting during delivery remain a great challenge.Herein,a stimulus-responsive system of mesoporous nanospheres(composed of Cu@Fe_(2)C@mSiO_(2))with good magnetothermal effect is introduced into the tumor microenvironment.This system plays an important role in image-guided controllable targeted drug delivery that is independent of tumor depth.Aggregation-induced emission luminogen-based fluorescence imaging and magnetic resonance imaging were utilized since these techniques visualize the delivery process in real time.In addition,the degraded nanocarriers showed high catalytic activity for Fenton and Fenton-like reactions,upregulating the level of hydroxyl radicals(•OH)in cancer cells to realize chemodynamic therapy.The induced•OH led to the overexpression of pho-STAT3,activating the STAT3 signaling pathway,eventually inducing cancer cell apoptosis.Through metabolic monitoring,this SDDS is removed from the body after its degradation in vivo.The synergistically enhanced therapeutic effect was obtained in the chemo-chemodynamic therapy of 4T1 tumor-bearing mice,offering a platform for efficient cancer therapy with a personalized theranostic strategy.展开更多
Stimulus-responsive materials are fundamental to the broad and ever-growing field of intelligence research,which bridge intelligent systems with the Internet of Things(loT)in future lifestyles.Among these materials,wr...Stimulus-responsive materials are fundamental to the broad and ever-growing field of intelligence research,which bridge intelligent systems with the Internet of Things(loT)in future lifestyles.Among these materials,writable materials have received great interest;however,carbonization and irreversible writing processes are generally inevitable for extensively investigated organic compounds.Photochromism is a potential mode of composing information.Nevertheless,inorganic materials usually exhibit weak photochromic effects.Here,a novel strategy of designing high-entropy perovskite(HEP)oxides is put forward to develop a new inorganic photochromic system with satisfying performance.A series of HEP oxides are synthesized for the first time.Benefiting from excellent photochromic features,real-time information encoding was achieved.The mechanism-related photochromism is also discussed.Distinct from the previous works,it is believed that the present photochromic-based HEP oxides provide a new and manyfold research space for the future development of conventional writable materials and the disclosing of unprecedented properties and phenomena.展开更多
Magnetic resonance imaging(MRI)has revolutionized medical imaging diagnostics with the advantages of non-invasive nature,absence of ionizing radiation,unrestricted penetration depth,high-resolution imaging of soft tis...Magnetic resonance imaging(MRI)has revolutionized medical imaging diagnostics with the advantages of non-invasive nature,absence of ionizing radiation,unrestricted penetration depth,high-resolution imaging of soft tissues,organs and blood vessels,and multi-parameter and multi-sequence imaging.Contrast agents(CAs)are crucial for enhancing image quality,detecting molecular-level changes,and providing comprehensive diagnostic information in contrast enhanced MRI.However,the performance of clinical Gd-based CAs represents a limitation to the improvement of MRI sensitivity,specificity,and versatility,thereby impeding the achievement of satisfactory imaging outcomes.In recent years,the development of magnetic nanoparticle-based CAs has emerged as a promising avenue to enhance the capabilities of MRI.Here,we review the advances in magnetic nanoparticle-based MRI CAs,including blood pool CAs,biochemically-targeted CAs,stimulus-responsive CAs,and ultra-high field MRI CAs,as well as the use of CAs for cell labeling and tracking.Additionally,we offer insights into the future prospects and challenges associated with the integration of these nanoparticles into clinical practice.展开更多
The external stimulus response strategy has been evolved rapidly in the field of olefin polymerization.In this work,we modularly synthesized three types of double stimulus responsiveα-diimine palladium catalysts,comb...The external stimulus response strategy has been evolved rapidly in the field of olefin polymerization.In this work,we modularly synthesized three types of double stimulus responsiveα-diimine palladium catalysts,combining redox regulation and other regulation together,such as light,Lewis acid and alkali cations.The catalytic activities and the molecular weight of polyethylene products can be regulated for 4 times in ethylene polymerization.These palladium complexes were also used for the copolymerization reaction of ethylene and polar monomers,such as methyl 10-undecylenate and methyl acrylate,effectively regulating the catalytic activities,the molecular weight and polar monomer incorporation of the prepared copolymers.The research on these dual-regulated palladium complexes makes full use of prepared catalysts and provides new inspirations for regulating olefin polymerization.展开更多
Increasing understanding of the pathogenesis of rheumatoid arthritis(RA)has remarkably promoted the development of effective therapeutic regimens of RA.Nevertheless,the inadequate response to current therapies in a pr...Increasing understanding of the pathogenesis of rheumatoid arthritis(RA)has remarkably promoted the development of effective therapeutic regimens of RA.Nevertheless,the inadequate response to current therapies in a proportion of patients,the systemic toxicity accompanied by longterm administration or distribution in non-targeted sites and the comprised efficacy caused by undesirable bioavailability,are still unsettled problems lying across the full remission of RA.So far,these existing limitations have inspired comprehensive academic researches on nanomedicines for RA treatment.A variety of versatile nanocarriers with controllable physicochemical properties,tailorable drug release pattern or active targeting ability were fabricated to enhance the drug delivery efficiency in RA treatment.This review aims to provide an up-to-date progress regarding to RA treatment using nanomedicines in the last 5 years and concisely discuss the potential application of several newly emerged therapeutic strategies such as inducing the antigen-specific tolerance,pro-resolving therapy or regulating the immunometabolism for RA treatments.展开更多
Stealth coating materials effectively extend a nanoparticle's systemic circulation lifetime yet limit its cellular internalization, which promotes and prevents tumor targeting, respectively. Here, this contradiction ...Stealth coating materials effectively extend a nanoparticle's systemic circulation lifetime yet limit its cellular internalization, which promotes and prevents tumor targeting, respectively. Here, this contradiction was resolved by using an acutely pH-sensitive zwitterionic stealth ligand capable of responding to small differences in extracellular pH between blood and tumors. Using a photothermal gold nanocage (AuNC) as a model nanotherapeutic, we found that stealth-AuNC nanoparticles showed both significantly enhanced cell uptake efficiency in acidic tumors and a markedly extended systemic circulation lifetime compared to its unaltered analogue. As a result, stealth-AuNC nanoparticles administered intravenously showed significantly enhanced accumulation within the tumor, leading to significantly improved photothermal therapeutic efficacy in mouse models. These results suggests that pH-sensitive zwitterionic ligands with sufficient sensitivity for responding to small differences in extracellular pH between blood and tumors are ideal stealth materials for simultaneously conferring both extended systemic circulation and enhanced cellular internalization, reducing the need for active targeting moieties.展开更多
Tumor vasculature constitutes a formidable hurdle for the efficient delivery of cancer nanomedicine into tumors.The leverage of passive pathway through inter-endothelial gaps in tumor blood vessels might account for l...Tumor vasculature constitutes a formidable hurdle for the efficient delivery of cancer nanomedicine into tumors.The leverage of passive pathway through inter-endothelial gaps in tumor blood vessels might account for limited extravasation of nanomedicine into tumor microenvironment(TME).Herein,Annexin A1 antibody-installed mesoporous organosilica nanoplatforms carrying immunotherapeutics of anti-PD-L1 antibody(aPD-L1)and Indoximod are developed to target at caveolar Annexin-A1 protein of luminal endothelial cells and to trigger the active trans-endothelial transcytosis of nanomedicine mediated by caveolae.Such strategy enables rapid nanomedicine extravasation across tumor endothelium and relatively extensive accumulation in tumor interstitium.aPD-L1 and Indoximod release from aPD/IND@MON-aANN in a reduction-responsive manner and synergistically facilitate the intratumoral infiltration of cytotoxic T lymphocytes and reverse the immunosuppressive TME,thus demonstrating substantial anti-tumor efficacy in subcutaneous 4T1 breast tumors and remarkable anti-metastatic capacity to extend the survival of 4T1 tumor metastasis model.Moreover,aPD/IND@MON-aANN nanomedicine also exhibits distinct superiority over the combination therapy of free drugs to potently attenuate the progression of urethane-induced orthotopic lung cancers.Collectively,aPD/IND@MON-aANN nanoplatforms with boosted delivery efficiency via antibody-activated trans-endothelial pathway and enhanced immunotherapeutic efficacy provides perspectives for the development of cancer nanomedicines.展开更多
Although patients benefit from surgical transurethral resection of bladder cancers,some niduses are missed or incompletely resected,and small malignant lesions may recur.Intravesical chemotherapy and immunotherapy are...Although patients benefit from surgical transurethral resection of bladder cancers,some niduses are missed or incompletely resected,and small malignant lesions may recur.Intravesical chemotherapy and immunotherapy are universally accepted as adjuvant treatments after surgery to avoid recurrence and progression.However,these treatments still have limitations,including an insufficient retention period,inefficient permeability of chemotherapeutic agents,and dilution of the agents by urine.Nanostructure-based smart therapeutic platforms can be tailored to be responsive to internal or external stimuli to ameliorate this situation.This unparalleled capability empowers the precise aggregation of stimulus–responsive nanocarriers in the target regions,namely,the tumors,and subsequent release of the anticancer materials.This review summarizes the current nanostructure-based therapeutic platforms,especially stimulus–responsive nanocarriers,and highlights their benefits and limitations in bladder cancer therapy.Novel innovations in nanotechnology have undoubtedly arrived at a new height and have become useful for practical applications.Nanotechnology will positively promote the development of anticancer agents not only for bladder cancer but also for other solid tumors.展开更多
In this paper, double hydrophilic ionic liquid block copolymers (ILBCs), poly(N-isopropylacrylamide)-block-poly[1-methyl-3-(2-methacryloyloxy propylimidazo- lium bromine)] (PNIPAM-b-PMMPImB), were polymerized ...In this paper, double hydrophilic ionic liquid block copolymers (ILBCs), poly(N-isopropylacrylamide)-block-poly[1-methyl-3-(2-methacryloyloxy propylimidazo- lium bromine)] (PNIPAM-b-PMMPImB), were polymerized by two-step reversible addi- tion-fragmentation chain transfer (RAFT) process. The composition and molecular weight distributions of ILBCs were characterized using 1HNMR and gel permeation chromato- graphy (GPC). The self-assembly and temperature- and anion-responsive behaviors of ILBCs were investigated by UV-Vis spectroscopy, TEM and dynamic light scattering (DLS). With increasing the concentration of (CF3SO2)2N-, the micellization of self- assembling PNIPAM-b-PMMPImB was induced to form a core-shell structure containing the core with hydrophilic PMMPIm-(CF3SO2)2N- surrounded by the shell of PNIPAM via the anion-responsive properties of ILBCs. However, upon temperature increasing, PNIPAM-b- PMMPImB formed the micelles composing of PNIPAM core and PMMPImB shell. The ionic liquid segment with strong hydrophilic property enhanced the hydrogen bonding interaction which expanded the temperature range of phase transition and increased the lower critical solution temperature (LCST) of the system. These results indicate that ILBCs prepared in this paper have excellent temperature and anion double responsive properties, and may be applied as a kind of potential environmental responsive polymer nanoparticles.展开更多
Insufficient intratumoral retention of nanomedicines remains the major challenge for broad implementation in clinical sets.Herein,we proposed a legumain-triggered aggregable gold nanoparticle(GNP)delivery platform(GNP...Insufficient intratumoral retention of nanomedicines remains the major challenge for broad implementation in clinical sets.Herein,we proposed a legumain-triggered aggregable gold nanoparticle(GNP)delivery platform(GNPs-A&C).GNPs-A&C could form intratumoral or intracellular aggregates in response to the overexpressed legumain.The aggregates with size increase not only could reduce back-flow from interstitial space to peripheral bloodstream but also could restrict the cellular exocytosis,leading to enhanced intratumoral retention.In vitro studies demonstrated that GNPs-A&C possessed an excellent legumain responsiveness and the increased size was closely relevant with legumain expression.In vivo studies demonstrated GNPs-A&C possessed slower clearance rate and much higher intratumoral retention within legumain-overexpressed tumor compared to non-aggregable NPs,regardless of intravenous or intratumoral injection.More importantly,this delivery platform significantly improved the chemotherapeutic effect of doxorubicin(DOX)towards subcutaneous xenograft C6 tumor.The effectiveness of this stimulus-responsive aggregable delivery system provides a thinking for designing more intelligent size-tunable nanomedicine that can substantially improve intratumoral retention.展开更多
文摘Shot and step response measurements were carried out with inert bed and adsorption bed both under iso-thermal conditions.Parameter values were determined from a time domain analysis of the measured inputand response signal.Sensitivity test in the parameter values showed that shot response measurements maygive more reliable parameter values than step measurements.Since Kubin[1]and Kucera[2]proposed a parameter estimation technique based on a moment methodfor adsorption system,attention has been focused on dynamic input-output measurements with variouspacked bed systems for the parameter estimation.The object of this work is to compare shot and step re-sponse measurements and see which measurement gives more reliable parameter values.
文摘The objective of this paper is to incorporate vehicle mix in stimulus-response car-following models. Separate models were estimated for acceleration and deceleration responses to account for vehicle mix via both movement state and vehicle type. For each model, three submodels were developed for different pairs of following vehicles including "automobile following automobile," "automobile following truck," and "truck following automobile." The estimated model parameters were then validated against other data from a similar region and roadway. The results indicated that drivers' behaviors were significantly different among the different pairs of following vehicles. Also the magnitude of the estimated parameters depends on the type of vehicle being driven and/or followed. These results demonstrated the need to use separate models depending on movement state and vehicle type. The differences in parameter estimates confirmed in this paper highlight traffic safety and operational issues of mixed traffic operation on a single lane. The findings of this paper can assist transportation professionals to improve traffic simulation models used to evaluate the impact of different strategies on ameliorate safety and performance of highways. In addition, driver response time lag estimates can be used in roadway design to calculate important design parameters such as stopping sight distance on horizontal and vertical curves for both automobiles and trucks.
基金supported by the National Natural Science Foundation of China (Nos. 52122511, 52105492, and 62005262)the National Key Research and Development Program of China (No. 2021YFF0502700)+2 种基金the Students’ Innovation and Entrepreneurship Foundation of USTC (Nos. CY2022G32 and XY2022G02CY)the USTC Research Funds of the Double First-Class Initiative (No. YD2340002009)CAS Project for Young Scientists in Basic Research (No. YSBR-049)
文摘Diverse natural organisms possess stimulus-responsive structures to adapt to the surrounding environment.Inspired by nature,researchers have developed various smart stimulus-responsive structures with adjustable properties and functions to address the demands of ever-changing application environments that are becoming more intricate.Among many fabrication methods for stimulus-responsive structures,femtosecond laser direct writing(FsLDW)has received increasing attention because of its high precision,simplicity,true three-dimensional machining ability,and wide applicability to almost all materials.This paper systematically outlines state-of-the-art research on stimulus-responsive structures prepared by FsLDW.Based on the introduction of femtosecond laser-matter interaction and mainstream FsLDW-based manufacturing strategies,different stimulating factors that can trigger structural responses of prepared intelligent structures,such as magnetic field,light,temperature,pH,and humidity,are emphatically summarized.Various applications of functional structures with stimuli-responsive dynamic behaviors fabricated by FsLDW,as well as the present obstacles and forthcoming development opportunities,are discussed.
基金Supported by the China National Science and Technology Major Project(2017ZX05009-003,2016ZX05020-004,2016ZX05040-005)
文摘AM-AMPS-TAC polymers with different charge distribution are synthesized using acrylamide(AM),2-acrylamido-2-methylpropanesulfonate(AMPS)and 3-acrylamidopropyl trimethylammonium(TAC)at different feed ratios by polymerization in solution.The salt-responsive behavior,reasons leading to salt-responsiveness,and effects of polymers molecular structure on salt-responsiveness are studied by laboratory experiments to find out the adaptability of the polymers.Rheology test under stepwise shear mode shows that the AM-AMPS-TAC polymers have salt responsiveness,and the closer the feeds of AMPS and ATC,the more significant the salt responsiveness will be.Conformation change of polymers molecular chain under salt stimulus is studied by turbidity test and micro-morphology analysis,and the responsive mechanism is further investigated by intrinsic viscosity test and copolymer composition analysis.Results indicate that the salt-responsive behavior of AM-AMPS-TAC polymers derives from the"curled to expanded"transition of chain conformation under salt stimulus,and this transition is led by the screening effect of salt which weakens polymers intramolecular ionic bond.Application in saturated saltwater drilling fluid shows that the AM90-AMPS5-TAC5 polymer has the best salt-tolerance and temperature-tolerance when used together with fluid loss controller PAC-Lv.The drilling fluid saturated with NaCl can maintain stable viscosity,good dispersion and low fluid loss for long time under 150℃.
基金supported by the National Key Basic Research Program of China (Grant No 2005CB623903)the National Natural Science Foundation of China (Grant No 50633020)+1 种基金the Program for Young Excellent Talents in Tongji University,the Special Project of Shanghai Nanotechnology (Grant No 0952nm04800)Natural Science Foundation of Shanghai (Grant No 10ZR1432100)
文摘Polymeric nanoparticles with unique properties are regarded as the most promising materials for biomedical applications including drug delivery and in vitro/in vivo imaging.Among them,stimulus-responsive polymeric nanoparticles,usually termed as "intelligent" nanoparticles,could undergo structure,shape,and property changes after being exposed to external signals including pH,temperature,magnetic field,and light,which could be used to modulate the macroscopical behavior of the nanoparticles.This paper reviews the recent progress in stimulus-responsive nanoparticles used for drug delivery and in vitro/in vivo imaging,with an emphasis on double/multiple stimulus-responsive systems and their biomedical applications.
基金the starting Grants of Tianjin University,Grant/Award Number:001Natural Science Foundation of Tianjin City+3 种基金National Natural Science Foundation of ChinaTianjin Universitythe starting Grants of Tianjin University and Tianjin Government,National Natural Science Foundation of China(No.51903188)Natural Science Foundation of Tianjin City(No.19JCQNJC04500)for financial support.
文摘Luminogens that exhibit stimulus-responsive room temperature phosphorescence(RTP)have attracted significant attention for their applications in a wide range of fields such as data storage,sensors,and bio-imaging.However,very few such materials are known,partly because of the unclear internal mechanism.In this review,we summarize recent advances in the field of stimulusresponsive RTP in purely organic luminogens,focusing on their unique emission behaviors and internal mechanisms governing the phenomena.We also attempt to identify the relationship between the mechanism,luminogens,and possible applications.
基金National Natural Science Foundation of China,Grant/Award Numbers:52073017,51773009FundamentalResearch Funds for the Central Universities+1 种基金NationalNatural Science Foundation of China,Grant/Award Numbers:52073017,51773009FundamentalResearch Funds for the Central Universities。
文摘Circularly polarized luminescence(CPL)has gained considerable attention in various systems and has rapidly developed into an emerging research field.To meet the needs of actual applications in diverse fields,a high luminescence dissymmetry factor(glum)and tunable optical performance of CPL would be the most urgent pursuit for researchers.Accordingly,many emerging CPL materials and various strategies have been developed to address these critical issues.Emissive cholesteric liquid crystals(CLCs),that is,luminescent self-organized helical superstructures,are considered to be ideal candidates for constructing CPL-active materials,as they not only exhibit high glum values,but also enable flexible optical control of CPL.This review mainly summarizes the characteristics of CPL based on CLCs as the bulk phase doped with different emitters,including aggregated induced emission molecules,conventional organic small molecules,polymer emitters,metal-organic complex emitters,and luminescent nanoparticles.In addition,the recent significant progress in stimulus-responsive CPL based on emissive CLCs in terms of several types of stimuli,including light,electricity,temperature,mechanical force,and multiple stimuli is presented.Finally,a short perspective on the opportunities and challenges associated with CPL-active materials based on the CLC field is provided.This review is anticipated to offer new insights and guidelines for developing CLC-based CPL-active materials for broader applications.
基金the financial support from the National Natural Science Foundation of China(No.22175033)Science and Technology Development Plan of Jilin Province(Nos.YDZJ202101ZYTS063,2021050822RQ)。
文摘Solid-state materials that exhibit pressure stimulus-response characteristics in a manner of emission signal,known as piezochromic luminescence(PCL),demonstrate great potential in photoelectric devices.The weakened luminescence and insignificant color change in the aggregation state,however,hampers their practical applications.Herein,a highly emissive coordination polymer,[Zn2(H4TTPE)(H2O)4]·H2O(CUST-805),is successfully constructed by employing an AIE-active chromophore as the building block.The structural characterization and photophysical properties are systematically studied.Owing to intrinsic twisted conformation and AIE feature of tetraphenylethylene-tetrazole ligand,CUST-805 achieves the visible and reversible PCL from blue to green switched by different external stimuli.The transformation between crystalline and amorphous states is proved to be the origin of present PCL behavior.Moreover,on basis of electron and energy transfer quenching mechanism,the highly selective and sensitive sensor based on CUST-805 is realized,showing the low detection limit of 0.29 ppm towards 2,4,6-trinitrophenol.
基金supported by the National Natural Science Foundation of China(grant nos.52027801,51631001,and 52001008)the National Key R&D Program of China(grant no.2017YFA0206301)+1 种基金the Natural Science Foundation of Beijing Municipality(grant no.2191001)the China-German Collaboration Project(grant no.M-0199).
文摘The development of smart drug delivery systems(SDDSs)based on engineered nanomaterials is important for clinical applications.Nevertheless,controllable administration of chemotherapeutic drugs for deep tumors and the avoidance of side effects caused by off-targeting during delivery remain a great challenge.Herein,a stimulus-responsive system of mesoporous nanospheres(composed of Cu@Fe_(2)C@mSiO_(2))with good magnetothermal effect is introduced into the tumor microenvironment.This system plays an important role in image-guided controllable targeted drug delivery that is independent of tumor depth.Aggregation-induced emission luminogen-based fluorescence imaging and magnetic resonance imaging were utilized since these techniques visualize the delivery process in real time.In addition,the degraded nanocarriers showed high catalytic activity for Fenton and Fenton-like reactions,upregulating the level of hydroxyl radicals(•OH)in cancer cells to realize chemodynamic therapy.The induced•OH led to the overexpression of pho-STAT3,activating the STAT3 signaling pathway,eventually inducing cancer cell apoptosis.Through metabolic monitoring,this SDDS is removed from the body after its degradation in vivo.The synergistically enhanced therapeutic effect was obtained in the chemo-chemodynamic therapy of 4T1 tumor-bearing mice,offering a platform for efficient cancer therapy with a personalized theranostic strategy.
基金supported by the National Natural Science Foundation of China(Nos.51772326 and 62105235)Natural Science Foundation of Tianjin City(No.22JCZDJC00010)+1 种基金Tianjin Research Innovation Project for Postgraduate Students(No.2022SKY153)the National Undergraduate Training Programs for Innovation and Entrepreneurship(No.202210059005).
文摘Stimulus-responsive materials are fundamental to the broad and ever-growing field of intelligence research,which bridge intelligent systems with the Internet of Things(loT)in future lifestyles.Among these materials,writable materials have received great interest;however,carbonization and irreversible writing processes are generally inevitable for extensively investigated organic compounds.Photochromism is a potential mode of composing information.Nevertheless,inorganic materials usually exhibit weak photochromic effects.Here,a novel strategy of designing high-entropy perovskite(HEP)oxides is put forward to develop a new inorganic photochromic system with satisfying performance.A series of HEP oxides are synthesized for the first time.Benefiting from excellent photochromic features,real-time information encoding was achieved.The mechanism-related photochromism is also discussed.Distinct from the previous works,it is believed that the present photochromic-based HEP oxides provide a new and manyfold research space for the future development of conventional writable materials and the disclosing of unprecedented properties and phenomena.
基金supported by the National Key R&D Program of China(Nos.2021YFA1201401 and 2021YFA1201402)the National Natural Science Foundation of China(Nos.82202306,82150301,82072063,and 31901003)+1 种基金the Guangdong Natural Science Foundation(No.2023A1515012508)the China Postdoctoral Science Foundation(Nos.2022M723700 and 2023T160776).
文摘Magnetic resonance imaging(MRI)has revolutionized medical imaging diagnostics with the advantages of non-invasive nature,absence of ionizing radiation,unrestricted penetration depth,high-resolution imaging of soft tissues,organs and blood vessels,and multi-parameter and multi-sequence imaging.Contrast agents(CAs)are crucial for enhancing image quality,detecting molecular-level changes,and providing comprehensive diagnostic information in contrast enhanced MRI.However,the performance of clinical Gd-based CAs represents a limitation to the improvement of MRI sensitivity,specificity,and versatility,thereby impeding the achievement of satisfactory imaging outcomes.In recent years,the development of magnetic nanoparticle-based CAs has emerged as a promising avenue to enhance the capabilities of MRI.Here,we review the advances in magnetic nanoparticle-based MRI CAs,including blood pool CAs,biochemically-targeted CAs,stimulus-responsive CAs,and ultra-high field MRI CAs,as well as the use of CAs for cell labeling and tracking.Additionally,we offer insights into the future prospects and challenges associated with the integration of these nanoparticles into clinical practice.
基金supported by National Natural Science Foundation of China(No.52203016)China Postdoctoral Science Foundation(Nos.2021M703072 and 2022T150617)+1 种基金USTC Research Funds of the Double First-Class Initiative(No.YD9990002018)The Fundamental Research Funds for the Central Universities(No.WK9990000142)。
文摘The external stimulus response strategy has been evolved rapidly in the field of olefin polymerization.In this work,we modularly synthesized three types of double stimulus responsiveα-diimine palladium catalysts,combining redox regulation and other regulation together,such as light,Lewis acid and alkali cations.The catalytic activities and the molecular weight of polyethylene products can be regulated for 4 times in ethylene polymerization.These palladium complexes were also used for the copolymerization reaction of ethylene and polar monomers,such as methyl 10-undecylenate and methyl acrylate,effectively regulating the catalytic activities,the molecular weight and polar monomer incorporation of the prepared copolymers.The research on these dual-regulated palladium complexes makes full use of prepared catalysts and provides new inspirations for regulating olefin polymerization.
基金supported by the National Natural Science Foundation of China(No.82003661)。
文摘Increasing understanding of the pathogenesis of rheumatoid arthritis(RA)has remarkably promoted the development of effective therapeutic regimens of RA.Nevertheless,the inadequate response to current therapies in a proportion of patients,the systemic toxicity accompanied by longterm administration or distribution in non-targeted sites and the comprised efficacy caused by undesirable bioavailability,are still unsettled problems lying across the full remission of RA.So far,these existing limitations have inspired comprehensive academic researches on nanomedicines for RA treatment.A variety of versatile nanocarriers with controllable physicochemical properties,tailorable drug release pattern or active targeting ability were fabricated to enhance the drug delivery efficiency in RA treatment.This review aims to provide an up-to-date progress regarding to RA treatment using nanomedicines in the last 5 years and concisely discuss the potential application of several newly emerged therapeutic strategies such as inducing the antigen-specific tolerance,pro-resolving therapy or regulating the immunometabolism for RA treatments.
文摘Stealth coating materials effectively extend a nanoparticle's systemic circulation lifetime yet limit its cellular internalization, which promotes and prevents tumor targeting, respectively. Here, this contradiction was resolved by using an acutely pH-sensitive zwitterionic stealth ligand capable of responding to small differences in extracellular pH between blood and tumors. Using a photothermal gold nanocage (AuNC) as a model nanotherapeutic, we found that stealth-AuNC nanoparticles showed both significantly enhanced cell uptake efficiency in acidic tumors and a markedly extended systemic circulation lifetime compared to its unaltered analogue. As a result, stealth-AuNC nanoparticles administered intravenously showed significantly enhanced accumulation within the tumor, leading to significantly improved photothermal therapeutic efficacy in mouse models. These results suggests that pH-sensitive zwitterionic ligands with sufficient sensitivity for responding to small differences in extracellular pH between blood and tumors are ideal stealth materials for simultaneously conferring both extended systemic circulation and enhanced cellular internalization, reducing the need for active targeting moieties.
基金This work was financially supported by the National Natural Science Foundation of China(NSFC 81472727,NSFC 81773259 and NSFC 91029718)Science and Technology Commission of Shanghai Municipality(15JC1403100)National laboratory of Oncogene and Cancer-related Genes foundation(90-15-05).
文摘Tumor vasculature constitutes a formidable hurdle for the efficient delivery of cancer nanomedicine into tumors.The leverage of passive pathway through inter-endothelial gaps in tumor blood vessels might account for limited extravasation of nanomedicine into tumor microenvironment(TME).Herein,Annexin A1 antibody-installed mesoporous organosilica nanoplatforms carrying immunotherapeutics of anti-PD-L1 antibody(aPD-L1)and Indoximod are developed to target at caveolar Annexin-A1 protein of luminal endothelial cells and to trigger the active trans-endothelial transcytosis of nanomedicine mediated by caveolae.Such strategy enables rapid nanomedicine extravasation across tumor endothelium and relatively extensive accumulation in tumor interstitium.aPD-L1 and Indoximod release from aPD/IND@MON-aANN in a reduction-responsive manner and synergistically facilitate the intratumoral infiltration of cytotoxic T lymphocytes and reverse the immunosuppressive TME,thus demonstrating substantial anti-tumor efficacy in subcutaneous 4T1 breast tumors and remarkable anti-metastatic capacity to extend the survival of 4T1 tumor metastasis model.Moreover,aPD/IND@MON-aANN nanomedicine also exhibits distinct superiority over the combination therapy of free drugs to potently attenuate the progression of urethane-induced orthotopic lung cancers.Collectively,aPD/IND@MON-aANN nanoplatforms with boosted delivery efficiency via antibody-activated trans-endothelial pathway and enhanced immunotherapeutic efficacy provides perspectives for the development of cancer nanomedicines.
基金the National Natural Science Foundation of China(Nos.21704104 and 81772754)Shenzhen Science and Technology Innovation Commission(Nos.RCYX20200714114645131 and JCYJ20190809164617205)+4 种基金Guangdong Basic and Applied Basic Research Foundation(Nos.2020A1515011443 and 2021A1515010669)Major Basic Research and Cultivation Program of Natural Science Foundation of Guangdong Province(No.2017A03038009)the Fundamental Research Funds for the Central Universities,Sun Yat-sen University(No.20ykpy17)Sanming Project of Medicine in Shenzhen(No.SZSM202011011)Research Start-up Fund of Part-time PI,SAHSYSU(No.ZSQYJZPI202003).
文摘Although patients benefit from surgical transurethral resection of bladder cancers,some niduses are missed or incompletely resected,and small malignant lesions may recur.Intravesical chemotherapy and immunotherapy are universally accepted as adjuvant treatments after surgery to avoid recurrence and progression.However,these treatments still have limitations,including an insufficient retention period,inefficient permeability of chemotherapeutic agents,and dilution of the agents by urine.Nanostructure-based smart therapeutic platforms can be tailored to be responsive to internal or external stimuli to ameliorate this situation.This unparalleled capability empowers the precise aggregation of stimulus–responsive nanocarriers in the target regions,namely,the tumors,and subsequent release of the anticancer materials.This review summarizes the current nanostructure-based therapeutic platforms,especially stimulus–responsive nanocarriers,and highlights their benefits and limitations in bladder cancer therapy.Novel innovations in nanotechnology have undoubtedly arrived at a new height and have become useful for practical applications.Nanotechnology will positively promote the development of anticancer agents not only for bladder cancer but also for other solid tumors.
文摘In this paper, double hydrophilic ionic liquid block copolymers (ILBCs), poly(N-isopropylacrylamide)-block-poly[1-methyl-3-(2-methacryloyloxy propylimidazo- lium bromine)] (PNIPAM-b-PMMPImB), were polymerized by two-step reversible addi- tion-fragmentation chain transfer (RAFT) process. The composition and molecular weight distributions of ILBCs were characterized using 1HNMR and gel permeation chromato- graphy (GPC). The self-assembly and temperature- and anion-responsive behaviors of ILBCs were investigated by UV-Vis spectroscopy, TEM and dynamic light scattering (DLS). With increasing the concentration of (CF3SO2)2N-, the micellization of self- assembling PNIPAM-b-PMMPImB was induced to form a core-shell structure containing the core with hydrophilic PMMPIm-(CF3SO2)2N- surrounded by the shell of PNIPAM via the anion-responsive properties of ILBCs. However, upon temperature increasing, PNIPAM-b- PMMPImB formed the micelles composing of PNIPAM core and PMMPImB shell. The ionic liquid segment with strong hydrophilic property enhanced the hydrogen bonding interaction which expanded the temperature range of phase transition and increased the lower critical solution temperature (LCST) of the system. These results indicate that ILBCs prepared in this paper have excellent temperature and anion double responsive properties, and may be applied as a kind of potential environmental responsive polymer nanoparticles.
基金supported by the Beijing Natural Science Foundation(No.L222128)Beijing Institute of Technology Research Fund Program for Young Scholars(No.XSQD-202121010)National Natural Science Foundation of China(No.81961138009)。
文摘Insufficient intratumoral retention of nanomedicines remains the major challenge for broad implementation in clinical sets.Herein,we proposed a legumain-triggered aggregable gold nanoparticle(GNP)delivery platform(GNPs-A&C).GNPs-A&C could form intratumoral or intracellular aggregates in response to the overexpressed legumain.The aggregates with size increase not only could reduce back-flow from interstitial space to peripheral bloodstream but also could restrict the cellular exocytosis,leading to enhanced intratumoral retention.In vitro studies demonstrated that GNPs-A&C possessed an excellent legumain responsiveness and the increased size was closely relevant with legumain expression.In vivo studies demonstrated GNPs-A&C possessed slower clearance rate and much higher intratumoral retention within legumain-overexpressed tumor compared to non-aggregable NPs,regardless of intravenous or intratumoral injection.More importantly,this delivery platform significantly improved the chemotherapeutic effect of doxorubicin(DOX)towards subcutaneous xenograft C6 tumor.The effectiveness of this stimulus-responsive aggregable delivery system provides a thinking for designing more intelligent size-tunable nanomedicine that can substantially improve intratumoral retention.
基金supported by the National Natural Science Foundation of China(52173094 and 52003062)Guangxi Natural Science Foundation of China(2019GXNSFFA245010)the Scientific and Technological Plan of Guilin City(20220110-1).