A reliable method for detecting nanoparticles is necessary for the wide application of nanomaterials. Single particle-inductively coupled plasma mass spectrometry(SP-ICP-MS) was investigated to detect the size of gold...A reliable method for detecting nanoparticles is necessary for the wide application of nanomaterials. Single particle-inductively coupled plasma mass spectrometry(SP-ICP-MS) was investigated to detect the size of gold nanoparticles(Au NPs) in this work. Discrimination of particle signal and iterative algorithm were used to calculate the baseline of particle signal. Influence of dwell time was discussed and 3 ms was selected as dwell time for size detection. Different Au NPs standards(30, 60, 80 and 100 nm) and mixed samples(60 and 100 nm) were determined by SP-ICP-MS and the accuracy was confirmed with reference values. The particle size detection limit was 19 nm in ultrapure water(UP water) and 31 nm in 0.1 μg/L Au^(3+) solution. Stability of Au NPs in ultrapure water and natural water samples was investigated by detecting size variation of AuN Ps. The result shows that Au NPs are stable in aqueous environment for 6 d but degraded after 30 d.展开更多
MicroRNAs(miRNAs)are small noncoding RNAs,which play a central role in gene expression regulation and have been considered as excellent biomarker candidates for clinical diagnosis and prognosis.So far,many miRNAs dete...MicroRNAs(miRNAs)are small noncoding RNAs,which play a central role in gene expression regulation and have been considered as excellent biomarker candidates for clinical diagnosis and prognosis.So far,many miRNAs detection methods require polymerase chain reaction(PCR)amplification following reverse transcription of miRNAs.These processes are complicated and time-consuming.In this work,we have developed a simpler method for miRNA detection based on base stacking hybridization happening on the surface of NaYF_4:Yb,Er upconversion nanoparticles.In this method,the fluorescence of NaYF_4:Yb,Er upconversion nanoparticles were functionalized as a reference standard,which can improve the accuracy of miRNA detection.On the basis of these findings,we suggest this novel approach for miRNA detection could be applied as an accurate and specific technique for miRNAs detection.展开更多
A review on the formation and unique physical and mechanical properties of metallic glassy fibers(MGFs)with the diameter ranging from micro to nano scales fabricated by a supercooled liquid extraction method(SLEM)is g...A review on the formation and unique physical and mechanical properties of metallic glassy fibers(MGFs)with the diameter ranging from micro to nano scales fabricated by a supercooled liquid extraction method(SLEM)is given.The SLEM method,through driving metallic glass rods in their supercooled liquid region via superplasticity,can fabricate MGFs with precisely designed and controlled size and properties,high structural uniformity and surface smoothness and extreme flexibility.The SLEM method is efficient and the MGFs can be continuously prepared by this method.A parameter f based on the thermal and rheological properties of MG-forming alloys is proposed to control the preparation and size of the fibers.We show that the novel MGFs with superior properties may attract intensive scientific interests and propel more engineering and functional applications.展开更多
基金Projects(21407182,21277175)supported by the National Natural Science Foundation of ChinaProject(20120162110019)supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China
文摘A reliable method for detecting nanoparticles is necessary for the wide application of nanomaterials. Single particle-inductively coupled plasma mass spectrometry(SP-ICP-MS) was investigated to detect the size of gold nanoparticles(Au NPs) in this work. Discrimination of particle signal and iterative algorithm were used to calculate the baseline of particle signal. Influence of dwell time was discussed and 3 ms was selected as dwell time for size detection. Different Au NPs standards(30, 60, 80 and 100 nm) and mixed samples(60 and 100 nm) were determined by SP-ICP-MS and the accuracy was confirmed with reference values. The particle size detection limit was 19 nm in ultrapure water(UP water) and 31 nm in 0.1 μg/L Au^(3+) solution. Stability of Au NPs in ultrapure water and natural water samples was investigated by detecting size variation of AuN Ps. The result shows that Au NPs are stable in aqueous environment for 6 d but degraded after 30 d.
基金the National Natural Science Foundation of China(61301039,21205036,31270908,61271056, 31540018)the Hunan Provincial Natural Science Foundation of China (13JJ4091)+2 种基金the Scientific Research Fund of Hunan Provincial Education Department(13A003)China Postdoctoral Science Foundation funded project(2014T70459)the Economical Forest Cultivation and Utilization of 2011 Collaborative Innovation Center in Hunan Province[(2013) 448]
文摘MicroRNAs(miRNAs)are small noncoding RNAs,which play a central role in gene expression regulation and have been considered as excellent biomarker candidates for clinical diagnosis and prognosis.So far,many miRNAs detection methods require polymerase chain reaction(PCR)amplification following reverse transcription of miRNAs.These processes are complicated and time-consuming.In this work,we have developed a simpler method for miRNA detection based on base stacking hybridization happening on the surface of NaYF_4:Yb,Er upconversion nanoparticles.In this method,the fluorescence of NaYF_4:Yb,Er upconversion nanoparticles were functionalized as a reference standard,which can improve the accuracy of miRNA detection.On the basis of these findings,we suggest this novel approach for miRNA detection could be applied as an accurate and specific technique for miRNAs detection.
基金supported by the National Natural Science Foundation of China(Grant Nos.51271195 and 51171204)the National Basic Research Program of China(Grant No.2010CB731603)
文摘A review on the formation and unique physical and mechanical properties of metallic glassy fibers(MGFs)with the diameter ranging from micro to nano scales fabricated by a supercooled liquid extraction method(SLEM)is given.The SLEM method,through driving metallic glass rods in their supercooled liquid region via superplasticity,can fabricate MGFs with precisely designed and controlled size and properties,high structural uniformity and surface smoothness and extreme flexibility.The SLEM method is efficient and the MGFs can be continuously prepared by this method.A parameter f based on the thermal and rheological properties of MG-forming alloys is proposed to control the preparation and size of the fibers.We show that the novel MGFs with superior properties may attract intensive scientific interests and propel more engineering and functional applications.
