The mechanical property of individual ferritin was measured with force-volume mapping (FV) under contact mode of atomic force microscopy (AFM) in this work. The elastic modulus of individual ferritin was estimated by ...The mechanical property of individual ferritin was measured with force-volume mapping (FV) under contact mode of atomic force microscopy (AFM) in this work. The elastic modulus of individual ferritin was estimated by the Hertz mode. The estimated value of the elastic modulus of individual ferritin was about 250-800 MPa under a small deformation. In addition, the elastic modulus of individual ferritin was compared with that of the colloid gold nanoparticle.展开更多
The advent of atomic force microscopy(AFM)provides a powerful tool for investigating the behaviors of single living cells under near physiological conditions.Besides acquiring the images of cellular ultra-microstructu...The advent of atomic force microscopy(AFM)provides a powerful tool for investigating the behaviors of single living cells under near physiological conditions.Besides acquiring the images of cellular ultra-microstructures with nanometer resolution,the most remarkable advances are achieved on the use of AFM indenting technique to quantify the mechanical properties of single living cells.By indenting single living cells with AFM tip,we can obtain the mechanical properties of cells and monitor their dynamic changes during the biological processes(e.g.,after the stimulation of drugs).AFM indentation-based mechanical analysis of single cells provides a novel approach to characterize the behaviors of cells from the perspective of biomechanics,considerably complementing the traditional biological experimental methods.Now,AFM indentation technique has been widely used in the life sciences,yielding a large amount of novel information that is meaningful to our understanding of the underlying mechanisms that govern the cellular biological functions.Here,based on the authors’own researches on AFM measurement of cellular mechanical properties,the principle and method of AFM indentation technique was presented,the recent progress of measuring the cellular mechanical properties using AFM was summarized,and the challenges of AFM single-cell nanomechanical analysis were discussed.展开更多
Although SnO_2-based nanomaterials used to be considered as being extraordinarily versatile for application to nanosensors,microelectronic devices, lithium-ion batteries, supercapacitors and other devices, the functio...Although SnO_2-based nanomaterials used to be considered as being extraordinarily versatile for application to nanosensors,microelectronic devices, lithium-ion batteries, supercapacitors and other devices, the functionalities of SnO_2-based nanomaterials are severely limited by their intrinsic vulnerabilities. Facile electrospinning was used to prepare SnO_2 nanofibers coated with a protective carbon layer. The mechanical properties of individual core-shell-structured SnO_2@C nanofibers were investigated by atomic force microscopy and the finite element method. The elastic moduli of the carbon-coated SnO_2 nanofibers remarkably increased, suggesting that coating SnO_2 nanofibers with carbon could be an effective method of improving their mechanical properties.展开更多
Based on tapping mode AFM imaging, a method was demonstrated to evaluate compression elasticity of single double-stranded DNA (dsDNA) molecules in the force region. With images under ambient conditions, Young’s modul...Based on tapping mode AFM imaging, a method was demonstrated to evaluate compression elasticity of single double-stranded DNA (dsDNA) molecules in the force region. With images under ambient conditions, Young’s moduli of dsDNA in compression were calculated. Results demonstrated that Young’s moduli of dsDNA can be simply deduced according to the proposed model. The method can also be used to evaluate the compression elasticity of similar soft nanomaterials.展开更多
基金Supported by the National Natural Science Foundation of China (Grant No. 10604034)Natural Science Foundation of Zhejiang Province (Grant No. Y606309)+1 种基金Ningbo Natural Science Foundation (Grant No. 2006A610046)K. C. Wong Magna Fund in Ningbo University
文摘The mechanical property of individual ferritin was measured with force-volume mapping (FV) under contact mode of atomic force microscopy (AFM) in this work. The elastic modulus of individual ferritin was estimated by the Hertz mode. The estimated value of the elastic modulus of individual ferritin was about 250-800 MPa under a small deformation. In addition, the elastic modulus of individual ferritin was compared with that of the colloid gold nanoparticle.
基金supported by the NationalNatural Science Foundation of China(61175103,61327014)CASFEA International Partnership Program for Creative Research Teams
文摘The advent of atomic force microscopy(AFM)provides a powerful tool for investigating the behaviors of single living cells under near physiological conditions.Besides acquiring the images of cellular ultra-microstructures with nanometer resolution,the most remarkable advances are achieved on the use of AFM indenting technique to quantify the mechanical properties of single living cells.By indenting single living cells with AFM tip,we can obtain the mechanical properties of cells and monitor their dynamic changes during the biological processes(e.g.,after the stimulation of drugs).AFM indentation-based mechanical analysis of single cells provides a novel approach to characterize the behaviors of cells from the perspective of biomechanics,considerably complementing the traditional biological experimental methods.Now,AFM indentation technique has been widely used in the life sciences,yielding a large amount of novel information that is meaningful to our understanding of the underlying mechanisms that govern the cellular biological functions.Here,based on the authors’own researches on AFM measurement of cellular mechanical properties,the principle and method of AFM indentation technique was presented,the recent progress of measuring the cellular mechanical properties using AFM was summarized,and the challenges of AFM single-cell nanomechanical analysis were discussed.
基金The project was supported by the National Natural Science Foundation of China(60904095,61175103)National High Technology Research and Development Program of China(863)(2009AA03Z316)Chinese Academy of Sciences Foreign Experts Affairs International Partnership Program for Creative Research Teams~~
基金supported by the National Natural Science Foundation of China(Grant Nos.51401176,51002128)the Scientific Research Foundation of the Hunan Provincial Education Department(Grant No.17A205)the Natural Science Foundation of Hunan Province(Grant No.2018JJ2393,2018JJ2394)
文摘Although SnO_2-based nanomaterials used to be considered as being extraordinarily versatile for application to nanosensors,microelectronic devices, lithium-ion batteries, supercapacitors and other devices, the functionalities of SnO_2-based nanomaterials are severely limited by their intrinsic vulnerabilities. Facile electrospinning was used to prepare SnO_2 nanofibers coated with a protective carbon layer. The mechanical properties of individual core-shell-structured SnO_2@C nanofibers were investigated by atomic force microscopy and the finite element method. The elastic moduli of the carbon-coated SnO_2 nanofibers remarkably increased, suggesting that coating SnO_2 nanofibers with carbon could be an effective method of improving their mechanical properties.
基金Supported by the National Key Scientific Program (Grant No. 2006CB933100)the Science Fund for Creative Research Groups of NSFC (Grant No. 20621502)China Postdoctoral Science Foundation (Grant No. 20060400867)
文摘Based on tapping mode AFM imaging, a method was demonstrated to evaluate compression elasticity of single double-stranded DNA (dsDNA) molecules in the force region. With images under ambient conditions, Young’s moduli of dsDNA in compression were calculated. Results demonstrated that Young’s moduli of dsDNA can be simply deduced according to the proposed model. The method can also be used to evaluate the compression elasticity of similar soft nanomaterials.
