By the electrochemical anodization method,we achieve the single-layer macroporous silicon on the N-type silicon,and prepare gold nanoparticles with sodium citrate reduction method. Through injecting the gold nanoparti...By the electrochemical anodization method,we achieve the single-layer macroporous silicon on the N-type silicon,and prepare gold nanoparticles with sodium citrate reduction method. Through injecting the gold nanoparticles into the porous silicon by immersion,the fluorescence quenching mechanism of porous silicon influenced by gold nanoparticles is analyzed. Then the macroporous silicon deposited with gold nanoparticles is utilized to enhance the fluorescence of rhodamine 6G(R6G). It is found that when the macroporous silicon is deposited with gold nanoparticles for 6 h,the maximum fluorescence enhancement of R6G(about ten times) can be realized. The N-type porous silicon deposited with gold nanoparticles can be an excellent substrate for fluorescence detection.展开更多
In this study,gold nanoparticles(AuNPs)were synthesized for rapid and sensitive characterization and quantification of chlorpyrifos in apples.Min-max signal adaptive zooming and second derivative transformation method...In this study,gold nanoparticles(AuNPs)were synthesized for rapid and sensitive characterization and quantification of chlorpyrifos in apples.Min-max signal adaptive zooming and second derivative transformation method were adopted to pre-process Raman spectral signal.The min-max signal adaptive zooming method showed a higher correlation coefficient than derivative transformation when developing linear calibration curve between chlorpyrifos pesticide and Raman spectral peak intensity.The present method had a high reproducibility with the relative standard deviation less than 15%.Regression models showed a good linear relationship(R=0.962)between intensity of characteristic spectral peaks(at 677 cm-1)and chlorpyrifos concentration on whole apples ranging from 0.13 mg/kg to 7.59 mg/kg.The application of surface enhancement Raman spectroscopy(SERS)detected chlorpyrifos pesticide to the detection limit of 0.13 mg/kg,which can be applied further for lower concentration in the future.The method presented in this study can provide a way-out for detection of pesticide residue in whole apple to trace amount.展开更多
As a widespread element,heavy metals have a significant impact on human health and threaten human health.It is of great significance to develop analytical technologies that can detect heavy metal ions quickly and accu...As a widespread element,heavy metals have a significant impact on human health and threaten human health.It is of great significance to develop analytical technologies that can detect heavy metal ions quickly and accurately.In comparison to conventional fluorescent materials such as organic dyes,quantum dot(QD)labels,and carbon quantum dots(CD),fluorescence detection technology utilizing lanthanide(Ln)ion-doped upconversion nanoparticles(UCNPs)stands out due to its distinctive attributes.These include a notably reduced autofluorescence background,enhanced tissue penetration capabilities,biocompatibility with cellular tissues,and minimal photodamage inflicted on biological samples.The utilization of this technology has garnered considerable attention across multiple fields.In the domain of heavy metal detection,traditional laboratory methods necessitate costly instrumentation and a fully equipped laboratory,involving intricate sample processing procedures and protracted detection periods,as well as a demand for skilled personnel.In contrast,the implementation of this material offers rapid and cost-effective detection,significantly mitigating the technical barriers for operators.Consequently,this represents an exceptional avenue to curtail expenses and broaden the scope of detection within the analytical process.This paper reviews the research progress of UCNPs in the detection of heavy metal ions,encompassing a brief elucidation of the luminescence principle of upconversion nanomaterials and commonly used detection principles.Additionally,it provides a detailed overview of the research status of several common non-metal ions and essential heavy metals.Furthermore,it summarizes the current focal points in UCNP detection and discusses the challenges and prospects associated with it.展开更多
Compositing gold nanoparticles into conjugated molecules have been developed to be one of the most important approaches to increase stability, since degradation of conjugated materials is now one of the biggest bottle...Compositing gold nanoparticles into conjugated molecules have been developed to be one of the most important approaches to increase stability, since degradation of conjugated materials is now one of the biggest bottle-necks to be conquered before industrialization application. Big-size colloidal gold nanoparticles with strong surface plasma resonance are designed to composite with conjugated molecules, in order to realize effective fluorescence enhancement and stabilization. The uniform composition film of hydrophilic colloidal gold nanoparticles (particle diameter of 30 nm) and hydrophobic carbazole functionalized fluorene trimers has been obtained by direct mixing of their aqueous and THF solutions, which is determined by AFM. By the comparison of composition based on fluorene trimers with similar structures, we have found that peripheral carbazole group and molecular size of fluorene trimers play an important role in the balance of incompatible solubility, which is regarded as increasing solubility of fluorene trimers in mixed solvent, connecting AuNP and peripheral carbazole groups, and restraining aggregate of gold nanoparticle. This allows facile hydrophilic gold nanoparticle to disperse uniformly in hydrophobic-conjugated host. Our investigations show that fluorescence intensity of composition film is enhanced by 4 folds, and heat treatment (200°C for 4h) for the composition film does not induce the degradation of conjugated backbone without the appearance of low-energy emission band, demonstrating the prominent potency of gold nanoparticles in enhanced fluorescence and stability of conjugated molecules and polymers.展开更多
本文基于荧光共振能量转移(fluorescence resonance energy transfer,FRET)技术设计构建纳米磷光探针。设计构建一种用于活细胞蛋白酶体实时活性检测的探针。主要设计思路为利用纳米金和铱金属配位化合物之间产生的FRET现象,通过目标蛋...本文基于荧光共振能量转移(fluorescence resonance energy transfer,FRET)技术设计构建纳米磷光探针。设计构建一种用于活细胞蛋白酶体实时活性检测的探针。主要设计思路为利用纳米金和铱金属配位化合物之间产生的FRET现象,通过目标蛋白酶的底物多肽连接二者。纳米磷光探针中的上述底物多肽被相应的蛋白酶体特异性识别和切割。FRET供体(铱)配合物与FRET受体(金纳米颗粒)分离,导致FRET现象消失,呈现铱配位配合物的绿色磷光信号。本研究所设计纳米探针针对蛋白酶体(目标蛋白)产生的磷光信号与其酶活性呈正相关,可用于试管和活细胞水平的蛋白酶体活性检测。此外,本研究中所述的酶活检测探针,针对不同的蛋白酶活性检测具有灵活的转变能力,通过多肽序列的替换,可获得目的蛋白酶活性检测磷光探针,大大拓展了其应用。展开更多
基金supported by the National Natural Science Foundation of China(Nos.61308120,61575168 and 11264038)the Doctor Startup Project of Xinjiang University(No.BS120122)+1 种基金the Young Talents Project in Xinjiang Uygur Autonomous Region(No.2013731003)the Xinjiang Science and Technology Project(Nos.2015211C262 and 2014211B003)
文摘By the electrochemical anodization method,we achieve the single-layer macroporous silicon on the N-type silicon,and prepare gold nanoparticles with sodium citrate reduction method. Through injecting the gold nanoparticles into the porous silicon by immersion,the fluorescence quenching mechanism of porous silicon influenced by gold nanoparticles is analyzed. Then the macroporous silicon deposited with gold nanoparticles is utilized to enhance the fluorescence of rhodamine 6G(R6G). It is found that when the macroporous silicon is deposited with gold nanoparticles for 6 h,the maximum fluorescence enhancement of R6G(about ten times) can be realized. The N-type porous silicon deposited with gold nanoparticles can be an excellent substrate for fluorescence detection.
基金The authors wish to thank the National Key Technology R&D Program(Project No.2015BAD19B03 and 2013BAD19B02),China,for providing funding support for this research.
文摘In this study,gold nanoparticles(AuNPs)were synthesized for rapid and sensitive characterization and quantification of chlorpyrifos in apples.Min-max signal adaptive zooming and second derivative transformation method were adopted to pre-process Raman spectral signal.The min-max signal adaptive zooming method showed a higher correlation coefficient than derivative transformation when developing linear calibration curve between chlorpyrifos pesticide and Raman spectral peak intensity.The present method had a high reproducibility with the relative standard deviation less than 15%.Regression models showed a good linear relationship(R=0.962)between intensity of characteristic spectral peaks(at 677 cm-1)and chlorpyrifos concentration on whole apples ranging from 0.13 mg/kg to 7.59 mg/kg.The application of surface enhancement Raman spectroscopy(SERS)detected chlorpyrifos pesticide to the detection limit of 0.13 mg/kg,which can be applied further for lower concentration in the future.The method presented in this study can provide a way-out for detection of pesticide residue in whole apple to trace amount.
基金supported by the Science and Technology Development Fund,Macao SAR(Grant 0065/2023/ITP2).
文摘As a widespread element,heavy metals have a significant impact on human health and threaten human health.It is of great significance to develop analytical technologies that can detect heavy metal ions quickly and accurately.In comparison to conventional fluorescent materials such as organic dyes,quantum dot(QD)labels,and carbon quantum dots(CD),fluorescence detection technology utilizing lanthanide(Ln)ion-doped upconversion nanoparticles(UCNPs)stands out due to its distinctive attributes.These include a notably reduced autofluorescence background,enhanced tissue penetration capabilities,biocompatibility with cellular tissues,and minimal photodamage inflicted on biological samples.The utilization of this technology has garnered considerable attention across multiple fields.In the domain of heavy metal detection,traditional laboratory methods necessitate costly instrumentation and a fully equipped laboratory,involving intricate sample processing procedures and protracted detection periods,as well as a demand for skilled personnel.In contrast,the implementation of this material offers rapid and cost-effective detection,significantly mitigating the technical barriers for operators.Consequently,this represents an exceptional avenue to curtail expenses and broaden the scope of detection within the analytical process.This paper reviews the research progress of UCNPs in the detection of heavy metal ions,encompassing a brief elucidation of the luminescence principle of upconversion nanomaterials and commonly used detection principles.Additionally,it provides a detailed overview of the research status of several common non-metal ions and essential heavy metals.Furthermore,it summarizes the current focal points in UCNP detection and discusses the challenges and prospects associated with it.
基金supported by the National Natural Science Foundation of China(20834006,50873043,91233113)the National Basic Research Program of China(2009CB623605,2013CB834705)+1 种基金Guangdong Natural Science Foundation(S2012030006232)Introduced Innovative R&D Team of Guangdong(201101C0105067115)
文摘Compositing gold nanoparticles into conjugated molecules have been developed to be one of the most important approaches to increase stability, since degradation of conjugated materials is now one of the biggest bottle-necks to be conquered before industrialization application. Big-size colloidal gold nanoparticles with strong surface plasma resonance are designed to composite with conjugated molecules, in order to realize effective fluorescence enhancement and stabilization. The uniform composition film of hydrophilic colloidal gold nanoparticles (particle diameter of 30 nm) and hydrophobic carbazole functionalized fluorene trimers has been obtained by direct mixing of their aqueous and THF solutions, which is determined by AFM. By the comparison of composition based on fluorene trimers with similar structures, we have found that peripheral carbazole group and molecular size of fluorene trimers play an important role in the balance of incompatible solubility, which is regarded as increasing solubility of fluorene trimers in mixed solvent, connecting AuNP and peripheral carbazole groups, and restraining aggregate of gold nanoparticle. This allows facile hydrophilic gold nanoparticle to disperse uniformly in hydrophobic-conjugated host. Our investigations show that fluorescence intensity of composition film is enhanced by 4 folds, and heat treatment (200°C for 4h) for the composition film does not induce the degradation of conjugated backbone without the appearance of low-energy emission band, demonstrating the prominent potency of gold nanoparticles in enhanced fluorescence and stability of conjugated molecules and polymers.
文摘本文基于荧光共振能量转移(fluorescence resonance energy transfer,FRET)技术设计构建纳米磷光探针。设计构建一种用于活细胞蛋白酶体实时活性检测的探针。主要设计思路为利用纳米金和铱金属配位化合物之间产生的FRET现象,通过目标蛋白酶的底物多肽连接二者。纳米磷光探针中的上述底物多肽被相应的蛋白酶体特异性识别和切割。FRET供体(铱)配合物与FRET受体(金纳米颗粒)分离,导致FRET现象消失,呈现铱配位配合物的绿色磷光信号。本研究所设计纳米探针针对蛋白酶体(目标蛋白)产生的磷光信号与其酶活性呈正相关,可用于试管和活细胞水平的蛋白酶体活性检测。此外,本研究中所述的酶活检测探针,针对不同的蛋白酶活性检测具有灵活的转变能力,通过多肽序列的替换,可获得目的蛋白酶活性检测磷光探针,大大拓展了其应用。
文摘建立了食品中香豆素的表面增强拉曼光谱定量分析法。以粒径约为55 nm的金纳米粒子为拉曼活性基底,以p H=5.0 HCl-KCl溶液为溶剂,釆用便携式拉曼仪进行分析。通过实验优化得到最佳测定条件（金纳米溶胶浓缩倍数为50倍,激光照射时间为5 s,金纳米溶胶与溶液的混合比例为1∶1）,建立了食品中游离香豆素直接检测方法,方法在1.0~100.0 mg/L的浓度范围内具有良好的线性,检出限为0.91 mg/L。将建立的分析方法用于蔬果、糖果、糕点等实际样品中香豆素的检测（样品前处理过程：称取10 g样品于烧杯中,加入50 m L溶剂,超声提取0.5 h后,定容至100 m L,摇匀后过滤,取10 m L定容至100 m L,摇匀得到样品处理液）,香豆素含量在0.61~5.52 g/kg之间;样品的加标回收率为75.12%~103.2%,相对标准偏差为0.6%~14%。结果表明,本方法快速准确、操作简单,可用于水果、糖果、糕点中香豆素的快速检测。
