A number of studies have indicated that bacteria able to emit red fluorescence can be detected by light in-duced fluorescence technique and killed by photodynamic therapy. The objective of this study was to investigat...A number of studies have indicated that bacteria able to emit red fluorescence can be detected by light in-duced fluorescence technique and killed by photodynamic therapy. The objective of this study was to investigate the red fluorescence properties of the single gram negative capnophilic bacterium Aggregatibacter actinomycetemcomitans, ATCC 33384, and to investigate if these properties were related to the growth, morphology and size of the bacterial colonies. Time trend assessment was made with red fluorescence by QLF (Quantitative Light-induced Fluorescence), as well as with white light digital imaging. It was demonstrated that A. actinomycetemcomitans, a single capnophilic bacterium, is able to produce red fluorescence on its own, i.e. in the absence of other bacteria strains, and that blood agar is necessary to obtain red fluorescence from this bacterium on culture plates. This bacterium formed smooth circular, bell/dome like colonies increasing in size with time exhibiting various red fluorescence behaviors. A large variation in the fluorescence behavior points out an inhomogeneous distribution of red fluorescence within and between the colonies, i.e. the size of the investigated colonies did not correlate with the red fluorescence area, suggesting a dependence on the colony morphology such as the colony growth in height. To our knowledge this is the first study that have shown that A. actinomycetemcomitans on its own is able to produce fluorescence in the red spectral region.展开更多
As a new type of luminescent material,carbon dots(CDs)have attracted increased attention for their superior optical properties in recent years.However,solidstate fluorescent CDs,especially with red emission,are still ...As a new type of luminescent material,carbon dots(CDs)have attracted increased attention for their superior optical properties in recent years.However,solidstate fluorescent CDs,especially with red emission,are still a major challenge.Here,CDs with solid-state red emission were synthesized by co-doping of N and B using the one-step microwave method.The CD powder exhibits excitation-independent solid-state red fluorescence without any dispersion matrices,with optimum solid-state fluorescence wavelength of 623 nm.The hydrogen bonding interaction in CDs is helpful for solid-state fluorescence of CDs.The IG/ID value of CDs reaches up to 3.49,suggesting their very high graphitization degree,which is responsible for their red emission.In addition,CDs show the concentration-induced multicolor emission,which is attributed to the decreased energy gap in the high concentrated CD solution.To exploit their concentration-dependent emission,CDs with changing ratio in matrices are applied as a color-converting layer on ultraviolet chip to fabricate multicolor light-emitting diodes with light coordinates of(0.33,0.38),(0.41,0.48),(0.49,0.44),and(0.67,0.33),which belong to green,yellow,orange,and red light,respectively.展开更多
We demonstrate the temperature-dependent fluorescence properties of Pr:LiGdF4 crystal tor the first time, to the best of our knowledge, and its blue diode pumped cw red laser at 720 nm at room temperature. The fluore...We demonstrate the temperature-dependent fluorescence properties of Pr:LiGdF4 crystal tor the first time, to the best of our knowledge, and its blue diode pumped cw red laser at 720 nm at room temperature. The fluorescence lifetime and polarized emission cross sections in the visible range are measured and calculated in a temperature range from 77K to 300 K, and the variations of the fluorescence lifetime and spectra are discovered. The reasons for these changes are explained accordingly. The output wavelength of the 720nm laser is first reported on the laser performance by using a fiber-coupled laser diode at the wavelength of 442nm as the pump source, and the maximum cw output power is about 303roW.展开更多
Gene specific primers and DNA probe were designed based on the sequence of 18S rDNA cloned from the red tide alga Thalassiosira rotula. A real-time fluorescent quantitative PCR (RFQ - PCR) method was developed for q...Gene specific primers and DNA probe were designed based on the sequence of 18S rDNA cloned from the red tide alga Thalassiosira rotula. A real-time fluorescent quantitative PCR (RFQ - PCR) method was developed for quantitative detection of T. rotula. The RFQ - PCR assay data showed that the results obtained with the RFQ - PCR quite good agreement with those with the light microscope (LM) counting method, which suggested that the RFQ - PCR could be a useful method for red tide alga detection.展开更多
[ Objective] This study was to construct an expression vector capable of excising selectable marker gene, further eliminating the effect of marker gene on the functional study of target gene. [ Method] By using Cre/Lo...[ Objective] This study was to construct an expression vector capable of excising selectable marker gene, further eliminating the effect of marker gene on the functional study of target gene. [ Method] By using Cre/LoxP site-specific recombination system, DsRed2-1 vector was modified by introducing LoxP se- quence and multiple cloning site sequence, then the TK gene was ligated into this vector for negative selection. [ Results] The fragments introduced were recom- bined at the molecular level under induced condition, and the specific red fluorescence was also observed in the recombinant vector transfected cells at the cellular level. [ Conclusion] It is feasible to use this Cre/loxP system to excise marker genes, showing a broad application prospect.展开更多
Red emissive carbon dots(CDs)powder was synthesized on a large scale from phloroglucinol and boric acid by a novel solid state reaction with yield up to 75%.This method is safe and convenient,for it needs neither high...Red emissive carbon dots(CDs)powder was synthesized on a large scale from phloroglucinol and boric acid by a novel solid state reaction with yield up to 75%.This method is safe and convenient,for it needs neither high pressure reactors nor complicated post-treatment procedures.The as-prepared carbon dots powder exhibited strong red fluorescence with excitation-independent behavior.XPS measurement and PL spectra suggest that such red fluorescence arise from boron-doped structures in CDs,which increases along with the boron concentration on CDs surface but decreases when the concentration quenching effect takes place.To overcome the aggregation induced fluorescence quenching of the solid CDs powder,the conventional methods are dispersing CDs into a large amount of inert substrates.But our present work provides a new strategy to realize strong red fluorescence of CDs in solid state.As a result,such carbon dots powder works well for latent fingerprint identification on various material surfaces.展开更多
Isophorone based red fluorescent compound 3 (dicyanomethylene) 5,5 dimethyl 1 [2 ( N ethyl 3 carbazyl)ethylene]~cyclo^he^xe^ne (DCDCC) was synthesized for use in organic light emitting diodes (OLEDs). DC...Isophorone based red fluorescent compound 3 (dicyanomethylene) 5,5 dimethyl 1 [2 ( N ethyl 3 carbazyl)ethylene]~cyclo^he^xe^ne (DCDCC) was synthesized for use in organic light emitting diodes (OLEDs). DCDCC was characterized by narrow emission in photoluminescence with full width at half maximum of only 50 nm in solution and in thin solid film of 70 nm width. Electroluminescence devices with configuration of ITO/NPB/Alq 3:DCDCC/Alq 3/Mg:Ag were fabricated utilizing DCDCC as dopant emitter. An efficient red emission peaked at 612 nm was obtained for the device with 1% (wt.%) DCDCC in Alq 3. The maximum luminance and current efficiency were as high as 3700 cd/m 2 at 14 V and 1.25 cd/A at 150 mA/cm 2, respectively.展开更多
Available online The abnormal carboxylesterase(CES)expression is closely related to many diseases such as hyperlipidemia,atherosclerosis,obesity,liver cancer,type 2 diabetes mellitus and gastrointestinal stromal tumor...Available online The abnormal carboxylesterase(CES)expression is closely related to many diseases such as hyperlipidemia,atherosclerosis,obesity,liver cancer,type 2 diabetes mellitus and gastrointestinal stromal tumors.The detection of a single enzyme in practical samples is often constrained by the structural diversity of CESs.Thus,the development of broad-carboxylesterase responsive fluorescent probe,which can detect the presence of wide variety of CESs,may provide overall or category information from another point of view,supplementing the deficiency of single detection for CES subspecies.Organelle lysosome is involved in various cell processes,such as cell signaling,apoptosis,secretion,and energy metabolism.Up to date,lysosome-targeted fluorescent probes,especially those with red emission(over 550 nm,with relatively low biological harmfulness),for CES detection are still rare.A lysosomes-targeted red fluorescent probe CES-Lyso was designed to monitor intracellular a variety of carboxylesterases alteration with wonderful selectivity and sensitivity,which was further applied to distinguish different derived breast cancer cells and monitor carboxylesterase activity in the anticancer drug treatment.展开更多
Rare earth luminous fiber was prepared by method of melt spinning. X-ray diffraction (XRD), scanning electron micros-copy (SEM), and fluorescence spectrophotometer as well as afterglow brightness tester were used ...Rare earth luminous fiber was prepared by method of melt spinning. X-ray diffraction (XRD), scanning electron micros-copy (SEM), and fluorescence spectrophotometer as well as afterglow brightness tester were used to characterize the resulting sam-ples. Results from XRD and SEM demonstrated that the phase of SrA12O4:Eu2+,Dy3+in the fiber was not destroyed in the manufac-turing process and the as-formed luminous fiber consisted of irregular particles. Under ultraviolet excitation, the luminous fiber exhib-ited a yellow-green and orange-red emission band with a maximum at 520 nm and around 600 nm originating from SrAl2O4:Eu2+, Dy3+and red organic fluorescent pigments. The energy transfer process was further studied. Furthermore, the emission colors of lu-minous fibers could be tuned from yellow-green to orange-red easily by doping red organic fluorescent pigment, making the materials have potential application in many areas.展开更多
Precise and early detection ofβ-amyloid(Aβ)deposits in situ and in real time is pivotal to the diagnosis and early intervention of Alzheimer’s disease(AD).Optical imaging stands out to be a promising technique for ...Precise and early detection ofβ-amyloid(Aβ)deposits in situ and in real time is pivotal to the diagnosis and early intervention of Alzheimer’s disease(AD).Optical imaging stands out to be a promising technique for such a task;however,it still remains a big challenge,due to the lack of high-performance imaging contrast agent.Restricted by poor blood-brain barrier(BBB)penetrability,short-wavelength excitation and emission,as well as the aggregation-caused quenching effect,the widely used goldstandard probes cannot be used for early in-vivo imaging of Aβdeposits.Herein,we integrate the Aβdeposits-favored geometry,amphiphilic and zwitterionic molecular structure,extended D-π-A electronic structure,and 3 D conformation into one molecule,facilely establishing a simple and economic imaging contrast agent that enjoys high specificity and affinity to Aβdeposits,good BBB penetrability,bright red/near-infrared fluorescence,low interference from autofluorescence,aggregation-induced emission(AIE)feature,high signal-to-noise ratio(SNR),and high contrast.In-vitro,ex-vivo,and in-vivo experiments with different strains of mice indicate that AIE-CNPy-AD holds the universality to Aβdeposits identification.Noteworthily,AIE-CNPy-AD is even able to precisely trace the small and sparsely-distributed Aβdeposits in AD model mice as young as 4-month-old APP/PS1 mice,the youngest having Aβdeposits.Moreover,the present probe could clearly reveal the increase and enlargement of Aβdeposits as the mice grow.Therefore,AIE-CNPy-AD might be an ideal alternative for early AD diagnosis and highly reliable monitoring of AD progression.展开更多
Two novel thieno-[3,4-b]-pyrazine-based molecules, TP-E and TP-O, were designed and synthesized for potential application as red fluorescent emitters. The bulky tetraphenylethylene groups were attached at the peripher...Two novel thieno-[3,4-b]-pyrazine-based molecules, TP-E and TP-O, were designed and synthesized for potential application as red fluorescent emitters. The bulky tetraphenylethylene groups were attached at the periphery of the thieno-[3,4-b]-pyrazine core to form the non-planar molecules, as efficient solid- state emitting materials. The peripheral groups were grafted to the emissive core through either a conjugated acetylene bond, or a non-conjugated ether bond. These molecules exhibit strnng red fluorescence in both dilute solutions and in thin films with large Stokes shifts of over 100 nm. The cyclic voltammetry measurements showed the reversible oxidation and reduction behavior for both compounds. All these properties indicate the two compounds are possible functional materials for use in ontoelectronic devices.展开更多
A cyano-substituted diarylethlene derivative aggregation-induced emission (ALE) dye with two amino end-groups and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride were facilely incorporated into red fluorescen...A cyano-substituted diarylethlene derivative aggregation-induced emission (ALE) dye with two amino end-groups and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride were facilely incorporated into red fluorescent organic nanoparticles (FONs) via room temperature anhydride ring-opening polymerization under an air atmosphere. These obtained RO-HFDA FONs were characterized by a series of techniques including gel permeation chromatography, Fourier transform infrared spectroscopy, size distribution and zeta potential measurements, UV-Vis absorption spectrum, fluorescent spectroscopy and transmission electron microscopy. Biocompatibility evaluation and cell uptake behavior of RO-HFDA FONs were further investigated to explore their potential biomedical application. We demonstrated that such FONs showed high water dispersibility, stable uniform spherical morphology (150-200 nm), broad excitation band (350-605 nm), intense red fluorescence (627 nm) and excellent biocompatibility, making them promising for cell imaging applications.展开更多
The versatile photosyntheticα-proteobacterium Rhodobacter sphaeroides,has recently been extensively engineered as a novel microbial cell factory(MCF)to produce pharmaceuticals,nutraceuticals,commodity chemicals and e...The versatile photosyntheticα-proteobacterium Rhodobacter sphaeroides,has recently been extensively engineered as a novel microbial cell factory(MCF)to produce pharmaceuticals,nutraceuticals,commodity chemicals and even hydrogen.However,there are no well-characterized high-activity promoters to modulate gene transcription during the engineering of R.sphaeroides.In this study,several native promoters from R.sphaeroides JDW-710(JDW-710),an industrial strain producing high levels of co-enzyme Q10(Q10)were selected on the basis of transcriptomic analysis.These candidate promoters were then characterized by using gusA as a reporter gene.Two native promoters,Prsp_7571 and Prsp_6124,showed 620%and 800%higher activity,respectively,than the tac promoter,which has previously been used for gene overexpression in R.sphaeroides.In addition,a Prsp_7571-derived synthetic promoter library with strengths ranging from 54%to 3200%of that of the tac promoter,was created on the basis of visualization of red fluorescent protein(RFP)expression in R.sphaeroides.Finally,as a demonstration,the synthetic pathway of Q10 was modulated by the selected promoter T334*in JDW-710;the Q10 yield in shake-flasks increased 28%and the production reached 226 mg/L.These well-characterized promoters should be highly useful in current synthetic biology platforms for refactoring the biosynthetic pathway in R.sphaeroides-derived MCFs.展开更多
基金supported by a grant from StureNymans Commemoration Fund
文摘A number of studies have indicated that bacteria able to emit red fluorescence can be detected by light in-duced fluorescence technique and killed by photodynamic therapy. The objective of this study was to investigate the red fluorescence properties of the single gram negative capnophilic bacterium Aggregatibacter actinomycetemcomitans, ATCC 33384, and to investigate if these properties were related to the growth, morphology and size of the bacterial colonies. Time trend assessment was made with red fluorescence by QLF (Quantitative Light-induced Fluorescence), as well as with white light digital imaging. It was demonstrated that A. actinomycetemcomitans, a single capnophilic bacterium, is able to produce red fluorescence on its own, i.e. in the absence of other bacteria strains, and that blood agar is necessary to obtain red fluorescence from this bacterium on culture plates. This bacterium formed smooth circular, bell/dome like colonies increasing in size with time exhibiting various red fluorescence behaviors. A large variation in the fluorescence behavior points out an inhomogeneous distribution of red fluorescence within and between the colonies, i.e. the size of the investigated colonies did not correlate with the red fluorescence area, suggesting a dependence on the colony morphology such as the colony growth in height. To our knowledge this is the first study that have shown that A. actinomycetemcomitans on its own is able to produce fluorescence in the red spectral region.
基金This work was financially supported by the Foundation Research Project of Shanxi Province(Grant Nos.202103021223007,20210302123164,and 20210302124604)the National Natural Science Foundation of China(Grant No.51972221)+2 种基金the Research Project Supported by Shanxi Scholarship Council of China(Grant Nos.2020-051 and HGKY2019027)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(Grant No.2019L0946)the Key Research Program of Lyuliang City(Grant No.GXZDYF2019087).
文摘As a new type of luminescent material,carbon dots(CDs)have attracted increased attention for their superior optical properties in recent years.However,solidstate fluorescent CDs,especially with red emission,are still a major challenge.Here,CDs with solid-state red emission were synthesized by co-doping of N and B using the one-step microwave method.The CD powder exhibits excitation-independent solid-state red fluorescence without any dispersion matrices,with optimum solid-state fluorescence wavelength of 623 nm.The hydrogen bonding interaction in CDs is helpful for solid-state fluorescence of CDs.The IG/ID value of CDs reaches up to 3.49,suggesting their very high graphitization degree,which is responsible for their red emission.In addition,CDs show the concentration-induced multicolor emission,which is attributed to the decreased energy gap in the high concentrated CD solution.To exploit their concentration-dependent emission,CDs with changing ratio in matrices are applied as a color-converting layer on ultraviolet chip to fabricate multicolor light-emitting diodes with light coordinates of(0.33,0.38),(0.41,0.48),(0.49,0.44),and(0.67,0.33),which belong to green,yellow,orange,and red light,respectively.
基金Supported by the National Natural Science Foundation of China under Grant Nos 51025210,51102156 and 51272131the Young and Middle-Aged Scientists Research Awards Fund of Shandong Province under Grant No BS2011CL024
文摘We demonstrate the temperature-dependent fluorescence properties of Pr:LiGdF4 crystal tor the first time, to the best of our knowledge, and its blue diode pumped cw red laser at 720 nm at room temperature. The fluorescence lifetime and polarized emission cross sections in the visible range are measured and calculated in a temperature range from 77K to 300 K, and the variations of the fluorescence lifetime and spectra are discovered. The reasons for these changes are explained accordingly. The output wavelength of the 720nm laser is first reported on the laser performance by using a fiber-coupled laser diode at the wavelength of 442nm as the pump source, and the maximum cw output power is about 303roW.
基金The research was supported by the National Natural Science Foundation of China under contract No.40406028the National High Technology Research and Development Program of China under contract No.2001AA635090.
文摘Gene specific primers and DNA probe were designed based on the sequence of 18S rDNA cloned from the red tide alga Thalassiosira rotula. A real-time fluorescent quantitative PCR (RFQ - PCR) method was developed for quantitative detection of T. rotula. The RFQ - PCR assay data showed that the results obtained with the RFQ - PCR quite good agreement with those with the light microscope (LM) counting method, which suggested that the RFQ - PCR could be a useful method for red tide alga detection.
基金Supported by Doctoral Funds of Xinjiang Production and Construction Corps(2011BB014)Guidance Program of Xinjiang Academy of Agricultural Reclamation Sciences(YYD201110)
文摘[ Objective] This study was to construct an expression vector capable of excising selectable marker gene, further eliminating the effect of marker gene on the functional study of target gene. [ Method] By using Cre/LoxP site-specific recombination system, DsRed2-1 vector was modified by introducing LoxP se- quence and multiple cloning site sequence, then the TK gene was ligated into this vector for negative selection. [ Results] The fragments introduced were recom- bined at the molecular level under induced condition, and the specific red fluorescence was also observed in the recombinant vector transfected cells at the cellular level. [ Conclusion] It is feasible to use this Cre/loxP system to excise marker genes, showing a broad application prospect.
基金financially supported by the National Natural Science Foundation of China(Nos.21975048,21771039)the Science and Technology Commission of Shanghai Municipality(No.19DZ2270100)。
文摘Red emissive carbon dots(CDs)powder was synthesized on a large scale from phloroglucinol and boric acid by a novel solid state reaction with yield up to 75%.This method is safe and convenient,for it needs neither high pressure reactors nor complicated post-treatment procedures.The as-prepared carbon dots powder exhibited strong red fluorescence with excitation-independent behavior.XPS measurement and PL spectra suggest that such red fluorescence arise from boron-doped structures in CDs,which increases along with the boron concentration on CDs surface but decreases when the concentration quenching effect takes place.To overcome the aggregation induced fluorescence quenching of the solid CDs powder,the conventional methods are dispersing CDs into a large amount of inert substrates.But our present work provides a new strategy to realize strong red fluorescence of CDs in solid state.As a result,such carbon dots powder works well for latent fingerprint identification on various material surfaces.
文摘Isophorone based red fluorescent compound 3 (dicyanomethylene) 5,5 dimethyl 1 [2 ( N ethyl 3 carbazyl)ethylene]~cyclo^he^xe^ne (DCDCC) was synthesized for use in organic light emitting diodes (OLEDs). DCDCC was characterized by narrow emission in photoluminescence with full width at half maximum of only 50 nm in solution and in thin solid film of 70 nm width. Electroluminescence devices with configuration of ITO/NPB/Alq 3:DCDCC/Alq 3/Mg:Ag were fabricated utilizing DCDCC as dopant emitter. An efficient red emission peaked at 612 nm was obtained for the device with 1% (wt.%) DCDCC in Alq 3. The maximum luminance and current efficiency were as high as 3700 cd/m 2 at 14 V and 1.25 cd/A at 150 mA/cm 2, respectively.
基金the financial support from the National Natural Science Foundation of China (No. 21705120)the Technology Support Project of Shandong Province Higher Educational Youth Innovation (No. 2019KJM008)+1 种基金the Natural Science Foundation of Shandong Province, China (No. ZR2017LB016)the Project of Shandong Province Higher Educational Science and Technology Program (No. J17KB074)
文摘Available online The abnormal carboxylesterase(CES)expression is closely related to many diseases such as hyperlipidemia,atherosclerosis,obesity,liver cancer,type 2 diabetes mellitus and gastrointestinal stromal tumors.The detection of a single enzyme in practical samples is often constrained by the structural diversity of CESs.Thus,the development of broad-carboxylesterase responsive fluorescent probe,which can detect the presence of wide variety of CESs,may provide overall or category information from another point of view,supplementing the deficiency of single detection for CES subspecies.Organelle lysosome is involved in various cell processes,such as cell signaling,apoptosis,secretion,and energy metabolism.Up to date,lysosome-targeted fluorescent probes,especially those with red emission(over 550 nm,with relatively low biological harmfulness),for CES detection are still rare.A lysosomes-targeted red fluorescent probe CES-Lyso was designed to monitor intracellular a variety of carboxylesterases alteration with wonderful selectivity and sensitivity,which was further applied to distinguish different derived breast cancer cells and monitor carboxylesterase activity in the anticancer drug treatment.
基金supported by the National Natural Science Foundation of China(21171074/B010201)National High-Tech R&D Program of China(863 Program)(2012AA030313)the Fundamental Research Funds for the Central Universities(JUDCF12021)
文摘Rare earth luminous fiber was prepared by method of melt spinning. X-ray diffraction (XRD), scanning electron micros-copy (SEM), and fluorescence spectrophotometer as well as afterglow brightness tester were used to characterize the resulting sam-ples. Results from XRD and SEM demonstrated that the phase of SrA12O4:Eu2+,Dy3+in the fiber was not destroyed in the manufac-turing process and the as-formed luminous fiber consisted of irregular particles. Under ultraviolet excitation, the luminous fiber exhib-ited a yellow-green and orange-red emission band with a maximum at 520 nm and around 600 nm originating from SrAl2O4:Eu2+, Dy3+and red organic fluorescent pigments. The energy transfer process was further studied. Furthermore, the emission colors of lu-minous fibers could be tuned from yellow-green to orange-red easily by doping red organic fluorescent pigment, making the materials have potential application in many areas.
基金supported by the National Natural Science Foundation of China(21788102,21875064,81903545,21604023,21790361)Shanghai Science and Technology Commission Basic Project-Shanghai Natural Science Foundation(21ZR1417600)+5 种基金Shanghai Municipal Science and Technology Major Project(2018SHZDZX03)Programme of Introducing Talents of Discipline to Universities(B16017)Shanghai Science and Technology Committee(17520750100)Beijing New-Star Plan of Science and Technology(Z201100006820009)Shanghai Sailing Program(16YF1402200)the Fundamental Research Funds for the Central Universities。
文摘Precise and early detection ofβ-amyloid(Aβ)deposits in situ and in real time is pivotal to the diagnosis and early intervention of Alzheimer’s disease(AD).Optical imaging stands out to be a promising technique for such a task;however,it still remains a big challenge,due to the lack of high-performance imaging contrast agent.Restricted by poor blood-brain barrier(BBB)penetrability,short-wavelength excitation and emission,as well as the aggregation-caused quenching effect,the widely used goldstandard probes cannot be used for early in-vivo imaging of Aβdeposits.Herein,we integrate the Aβdeposits-favored geometry,amphiphilic and zwitterionic molecular structure,extended D-π-A electronic structure,and 3 D conformation into one molecule,facilely establishing a simple and economic imaging contrast agent that enjoys high specificity and affinity to Aβdeposits,good BBB penetrability,bright red/near-infrared fluorescence,low interference from autofluorescence,aggregation-induced emission(AIE)feature,high signal-to-noise ratio(SNR),and high contrast.In-vitro,ex-vivo,and in-vivo experiments with different strains of mice indicate that AIE-CNPy-AD holds the universality to Aβdeposits identification.Noteworthily,AIE-CNPy-AD is even able to precisely trace the small and sparsely-distributed Aβdeposits in AD model mice as young as 4-month-old APP/PS1 mice,the youngest having Aβdeposits.Moreover,the present probe could clearly reveal the increase and enlargement of Aβdeposits as the mice grow.Therefore,AIE-CNPy-AD might be an ideal alternative for early AD diagnosis and highly reliable monitoring of AD progression.
基金the National Natural Science Foundation of China(Nos.21274016 and 21072026)Fundamental Research Funds for the Central Universities(No.DUT13LK06)for financial support to this work
文摘Two novel thieno-[3,4-b]-pyrazine-based molecules, TP-E and TP-O, were designed and synthesized for potential application as red fluorescent emitters. The bulky tetraphenylethylene groups were attached at the periphery of the thieno-[3,4-b]-pyrazine core to form the non-planar molecules, as efficient solid- state emitting materials. The peripheral groups were grafted to the emissive core through either a conjugated acetylene bond, or a non-conjugated ether bond. These molecules exhibit strnng red fluorescence in both dilute solutions and in thin films with large Stokes shifts of over 100 nm. The cyclic voltammetry measurements showed the reversible oxidation and reduction behavior for both compounds. All these properties indicate the two compounds are possible functional materials for use in ontoelectronic devices.
基金financially supported by the National Natural Science Foundation of China(Nos.21134004,21201108 and 51363016)the National 973 Project(No.2011CB935700)China Postdoctoral Science Foundation(Nos.2012M520243,2013T60100)
文摘A cyano-substituted diarylethlene derivative aggregation-induced emission (ALE) dye with two amino end-groups and 4,4'-(hexafluoroisopropylidene)diphthalic anhydride were facilely incorporated into red fluorescent organic nanoparticles (FONs) via room temperature anhydride ring-opening polymerization under an air atmosphere. These obtained RO-HFDA FONs were characterized by a series of techniques including gel permeation chromatography, Fourier transform infrared spectroscopy, size distribution and zeta potential measurements, UV-Vis absorption spectrum, fluorescent spectroscopy and transmission electron microscopy. Biocompatibility evaluation and cell uptake behavior of RO-HFDA FONs were further investigated to explore their potential biomedical application. We demonstrated that such FONs showed high water dispersibility, stable uniform spherical morphology (150-200 nm), broad excitation band (350-605 nm), intense red fluorescence (627 nm) and excellent biocompatibility, making them promising for cell imaging applications.
基金This work was supported by the National Natural Science Foundation of China[31870040]the National Key Research and Development Project(2020YFA0907804,2020YFA0907304)+1 种基金the“111”Project of China[B18022]the Fundamental Research Funds for the Central Universities[22221818014],and the Open Project Funding of the State Key Laboratory of Bioreactor Engineering.
文摘The versatile photosyntheticα-proteobacterium Rhodobacter sphaeroides,has recently been extensively engineered as a novel microbial cell factory(MCF)to produce pharmaceuticals,nutraceuticals,commodity chemicals and even hydrogen.However,there are no well-characterized high-activity promoters to modulate gene transcription during the engineering of R.sphaeroides.In this study,several native promoters from R.sphaeroides JDW-710(JDW-710),an industrial strain producing high levels of co-enzyme Q10(Q10)were selected on the basis of transcriptomic analysis.These candidate promoters were then characterized by using gusA as a reporter gene.Two native promoters,Prsp_7571 and Prsp_6124,showed 620%and 800%higher activity,respectively,than the tac promoter,which has previously been used for gene overexpression in R.sphaeroides.In addition,a Prsp_7571-derived synthetic promoter library with strengths ranging from 54%to 3200%of that of the tac promoter,was created on the basis of visualization of red fluorescent protein(RFP)expression in R.sphaeroides.Finally,as a demonstration,the synthetic pathway of Q10 was modulated by the selected promoter T334*in JDW-710;the Q10 yield in shake-flasks increased 28%and the production reached 226 mg/L.These well-characterized promoters should be highly useful in current synthetic biology platforms for refactoring the biosynthetic pathway in R.sphaeroides-derived MCFs.