To take advantage of the polymer's special properties, we synthesized PVDAT coated polystyrene(PVDAT@PS) microspheres through semi-continuous precipitation polymerization, and demonstrated the possibility of contro...To take advantage of the polymer's special properties, we synthesized PVDAT coated polystyrene(PVDAT@PS) microspheres through semi-continuous precipitation polymerization, and demonstrated the possibility of controlling the size of microspheres by using different sized PS cores. Mechanism of the microsphere synthesis was investigated. Preliminary application studies indicated that the synthesized microspheres adsorbed double-stranded DNAs(dsDNAs) comprising A-T base pairs in pH7.4 phosphate buffered saline, and the adsorption capacity was in a range of 3.28 mg to 5.58 mg per gram PVDAT@PS microspheres depending on A-T base pair percentage and chain length of the dsDNAs.展开更多
Boundary constraint induced inhomogeneous effects are important for mechanical responses of nano/micro-devices.For microcantilever sensors,the clamped-end constraint induced inhomogeneous effect of static deformation,...Boundary constraint induced inhomogeneous effects are important for mechanical responses of nano/micro-devices.For microcantilever sensors,the clamped-end constraint induced inhomogeneous effect of static deformation,so called the clamped-end effect,has great influence on the detection signals.This paper is devoted to developing an alternative mechanical model to characterize the clamped-end effect on the static detection signals of the DNA-microcantilever.Different from the previous concentrated load models,the DNA adsorption is taken as an equivalent uniformly distributed tangential load on the substrate upper surface,which exactly satisfies the zero force boundary condition at the free-end.Thereout,a variable coefficient differential governing equation describing the non-uniform deformation of the DNA-microcantilever induced by the clamped-end constraint is established by using the principle of minimum potential energy.By reducing the order of the governing equation,the analytical solutions of the curvature distribution and static bending deflection are obtained.By comparing with the previous approximate surface stress models,the clamped-end effect on the static deflection signals is discussed,and the importance of the neutral axis shift effect is also illustrated for the asymmetric laminated microcantilever.展开更多
基金the National Natural Science Foundation of China(Nos.51303049,51603065 and 21401051)
文摘To take advantage of the polymer's special properties, we synthesized PVDAT coated polystyrene(PVDAT@PS) microspheres through semi-continuous precipitation polymerization, and demonstrated the possibility of controlling the size of microspheres by using different sized PS cores. Mechanism of the microsphere synthesis was investigated. Preliminary application studies indicated that the synthesized microspheres adsorbed double-stranded DNAs(dsDNAs) comprising A-T base pairs in pH7.4 phosphate buffered saline, and the adsorption capacity was in a range of 3.28 mg to 5.58 mg per gram PVDAT@PS microspheres depending on A-T base pair percentage and chain length of the dsDNAs.
基金the National Natural Science Foundation of China (Nos.11772182, 11272193,and 10872121)the Program of Shanghai Municipal Education Commission (No. 2019-01-07-00-09-E00018)。
文摘Boundary constraint induced inhomogeneous effects are important for mechanical responses of nano/micro-devices.For microcantilever sensors,the clamped-end constraint induced inhomogeneous effect of static deformation,so called the clamped-end effect,has great influence on the detection signals.This paper is devoted to developing an alternative mechanical model to characterize the clamped-end effect on the static detection signals of the DNA-microcantilever.Different from the previous concentrated load models,the DNA adsorption is taken as an equivalent uniformly distributed tangential load on the substrate upper surface,which exactly satisfies the zero force boundary condition at the free-end.Thereout,a variable coefficient differential governing equation describing the non-uniform deformation of the DNA-microcantilever induced by the clamped-end constraint is established by using the principle of minimum potential energy.By reducing the order of the governing equation,the analytical solutions of the curvature distribution and static bending deflection are obtained.By comparing with the previous approximate surface stress models,the clamped-end effect on the static deflection signals is discussed,and the importance of the neutral axis shift effect is also illustrated for the asymmetric laminated microcantilever.