Au-Ag Gradient Alloy Nanoparticles with Extended Surface Plasmon Resonance Wavelength: Synthesis via Microreaction

Sun, Li; Luan, Weiling; Tu, Shan‐Tung; Shan, Yue Jin

doi:10.5101/nbe.v3i4.p232-235

Cited by 7 publications

(3 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…UV-vis spectra were recorded as a function of time from 3 to 21 h (Figure 1). It was obvious that the nanostructure Au-Ag alloy began to appear at 7 h, and the reaction almost completed at 16 h. The presence of only one plasmon resonance band in UV-vis absorption at 548 nm indicated that the nanostructure Au-Ag was formed as an alloy [28,29] rather than either a segregated metal or a core/shell structure characterized by two SPR bands [5,6]. …”

Section: Resultsmentioning

confidence: 99%

Chloroplasts-mediated biosynthesis of nanoscale Au-Ag alloy for 2-butanone assay based on electrochemical sensor

et al. 2012

View full text Add to dashboard Cite

We reported a one-pot, environmentally friendly method for biosynthesizing nanoscale Au-Ag alloy using chloroplasts as reducers and stabilizers. The prepared nanoscale Au-Ag alloy was characterized by UV–visible spectroscopy, X-ray diffraction (XRD) and high resolution transmission electron microscopy (HR-TEM). Fourier transform infrared spectroscopy (FTIR) analysis was further used to identify the possible biomolecules from chloroplasts that are responsible for the formation and stabilization of Au-Ag alloy. The FTIR results showed that chloroplast proteins bound to the nanoscale Au-Ag alloy through free amino groups. The bimetallic Au-Ag nanoparticles have only one plasmon band, indicating the formation of an alloy structure. HR-TEM images showed that the prepared Au-Ag alloy was spherical and 15 to 20 nm in diameter. The high crystallinity of the Au-Ag alloy was confirmed by SAED and XRD patterns. The prepared Au-Ag alloy was dispersed into multiwalled carbon nanotubes (MWNTs) to form a nanosensing film. The nanosensing film exhibited high electrocatalytic activity for 2-butanone oxidation at room temperature. The anodic peak current (Ip) has a linear relationship with the concentrations of 2-butanone over the range of 0.01% to 0.075% (v/v), when analyzed by cyclic voltammetry. The excellent electronic catalytic characteristics might be attributed to the synergistic electron transfer effects of Au-Ag alloy and MWNTs. It can reasonably be expected that this electrochemical biosensor provided a promising platform for developing a breath sensor to screen and pre-warn of early cancer, especially gastric cancer.

show abstract

Section: Resultsmentioning

confidence: 99%

Chloroplasts-mediated biosynthesis of nanoscale Au-Ag alloy for 2-butanone assay based on electrochemical sensor

et al. 2012

View full text Add to dashboard Cite

show abstract

“…Also, in situ spectroscopic techniques [34] have been used to monitor the growth of nanocrystals. The use of microreactors in microfluidic systems with in situ monitoring technology in the synthesis of nanocrystals [20,[30][31][32][33][34][35] provides us a feasible approach to control the synthesis process and to analyze the growth behavior of perovskite nanocrystals.…”

Section: Introductionmentioning

confidence: 99%

Growth of perovskite nanocrystals in poly-tetra fluoroethylene based microsystem: on-line and off-line measurements

Zhang¹,

Luan²,

Huang³

et al. 2019

Nanotechnology

Self Cite

View full text Add to dashboard Cite

Cesium lead halide perovskite nanocrystals are photoelectric nanomaterials that have potential applications in a variety of areas due to their excellent photoelectric and tunable photo luminescent properties. In this work, we investigate the synergetic effects of reaction temperature, reaction-capillary length and flow rate on the growth kinetics of perovskite nanocrystals in a PTFE-based microsystem and the photoluminescence characteristics of the perovskite nanocrystals both on-line and off-line. The on-line measurement finds that increasing the reaction temperature leads to the increase of the wavelength of the PL emission peak of the synthesized nanocrystals and reduces the average size of the perovskite nanocrystals synthesized in long reaction-capillaries. The intensity of the PL emission peak of the nanocrystals synthesized at different reaction temperatures decreases with the increase of the flow rate. The off-line measurement reveals that increasing the flow rate generally leads to the blueshift of the PL emission peaks and the decrease of the average size of the perovskite nanocrystals synthesized at the reaction temperature of 160 °C in the capillary length of 60 cm. Increasing temperature leads to the increase of the emission wavelength of the perovskite nanocrystals from 560 to 608 nm. The temperature dependence of the average size of the synthesized nanocrystals with the same synthesis conditions at different temperatures can be described by the Arrhenius relationship with an activation energy of 8.54 kJ mol −1 . Five different cross-sections of the synthesized perovskite nanocrystals are observed, including rhombus, hexagon, rectangle, square and quadrangle with three of them being observed for the first time.

show abstract

“…These examples fully demonstrate using carbon nanotubes and noble metal nanoparticles to develop ultrasensitive electrode interfaces is a good design strategy for fabricating new generation of electrochemical biosensors, because the nanocomposites of CNTs/nobel metal nanoparticles could enhance the performance of electrochemical biosensors 36 , 37 , for example, to improve the sensitivity of electrochemical sensors and to increase electron-transfer resistance because of their nanostructure and large surface area 38 - 40 . In recent years, nobel metal nanoparticles, especially bimetallic nanoparticles, for example, Au-Ag alloy nanoparticles, because of synergistic catalytic abilities, and selectivity of electrochemical reactions, exhibit great potential in development of new generation of electrochemical biosensors 41 - 43 .…”

Section: Introductionmentioning

confidence: 99%

Identification of Volatile Biomarkers of Gastric Cancer Cells and Ultrasensitive Electrochemical Detection based on Sensing Interface of Au-Ag Alloy coated MWCNTs

Zhang¹,

Gao²,

Liu³

et al. 2014

Theranostics

View full text Add to dashboard Cite

Successful development of novel electrochemical biosensing interface for ultrasensitive detection of volatile biomarkers of gastric cancer cells is a challenging task. Herein we reported to screen out novel volatile biomarkers associated with gastric cancer cells and develop a novel Au-Ag alloy composites-coated MWCNTs as sensing interface for ultrasensitive detection of volatile biomarkers. MGC-803 gastric cancer cells and GES-1 gastric mucous cells were cultured in serum-free media. The sample preparation approaches and HS-SPME conditions were optimized for screening volatile biomarkers. Volatiles emitted from the headspace of the cells/medium culture were identified using GC-MS. The Au-Ag nanoparticles-coated multiwalled carbon nanotubes were prepared as a sensing interface for detection of volatile biomarkers. Results showed that eight different volatile metabolites were screened out between MGC-803 cells and GES-1 cells. Two compounds such as 3-octanone and butanone were specifically present in the headspace of the MGC-803 cells. Three volatiles such as 4-isopropoxybutanol, nonanol and 4-butoxy 1-butanol coexisted in the headspace of both the MGC-803 cells and the GES-1 cells, their concentrations in the headspace of the GES-1cells were markedly higher than those in the MGC-803 cells, three volatiles such as formic acid propyl ester, 1.4-butanediol and 2, 6, 11-trimethyl dodecane solely existed in the headspace of the GES-1 cells. The nanocomposites of MWNTs loaded with Au-Ag nanoparticles were prepared as a electrochemical sensing interface for detection of two volatile biomarkers, cyclic voltammetry studies showed that the fabricated sensor could detect 3-octanone in the range of 0~0.0025% (v/v) and with a detection limitation of 0.3 ppb, could detect butanone in the range of 0 ~ 0.055% (v/v), and with a detection limitation of 0.5 ppb, and exhibited good selectivity. The novel electrochemical biosensor combined with volatile biomarkers of gastric cancer owns great potential in applications such as early diagnosis and the prognosis of gastric cancer in near future.

show abstract

Au-Ag Gradient Alloy Nanoparticles with Extended Surface Plasmon Resonance Wavelength: Synthesis via Microreaction

Abstract: Au-Ag gradient alloy nanoparticles were directly synthesized in a microreaction system with their surface plasmon resonance been facilely adjusted.The surface plasmon resonance wavelength was red-shifted through increasing the raw ratio of Au

Cited by 7 publications

References 6 publications

Chloroplasts-mediated biosynthesis of nanoscale Au-Ag alloy for 2-butanone assay based on electrochemical sensor

Chloroplasts-mediated biosynthesis of nanoscale Au-Ag alloy for 2-butanone assay based on electrochemical sensor

Growth of perovskite nanocrystals in poly-tetra fluoroethylene based microsystem: on-line and off-line measurements

Identification of Volatile Biomarkers of Gastric Cancer Cells and Ultrasensitive Electrochemical Detection based on Sensing Interface of Au-Ag Alloy coated MWCNTs

Contact Info

Product

Resources

About