Grayscale structured surfaces with nanometer-scale features are used in a growing number of applications in optics and fluidics.Thermal scanning probe lithography achieves a lateral resolution below 10 nm and a vertic...Grayscale structured surfaces with nanometer-scale features are used in a growing number of applications in optics and fluidics.Thermal scanning probe lithography achieves a lateral resolution below 10 nm and a vertical resolution below 1 nm,but its maximum depth in polymers is limited.Here,we present an innovative combination of nanowriting in thermal resist and plasma dry etching with substrate cooling,which achieves up to 10-fold amplification of polymer nanopatterns into SiO_(2) without proportionally increasing surface roughness.Sinusoidal nanopatterns in SiO_(2) with 400 nm pitch and 150 nm depth are fabricated free of shape distortion after dry etching.To exemplify the possible applications of the proposed method,grayscale dielectric nanostructures are used for scalable manufacturing through nanoimprint lithography and for strain nanoengineering of 2D materials.Such a method for aspect ratio amplification and smooth grayscale nanopatterning has the potential to find application in the fabrication of photonic and nanoelectronic devices.展开更多
The atomic force microscope has become an established research tool for imaging microorganisms with unprecedented resolution.However,its use in microbiology has been limited by the difficulty of proper bacterial immob...The atomic force microscope has become an established research tool for imaging microorganisms with unprecedented resolution.However,its use in microbiology has been limited by the difficulty of proper bacterial immobilization.Here,we have developed a microfluidic device that solves the issue of bacterial immobilization for atomic force microscopy under physiological conditions.Our device is able to rapidly immobilize bacteria in well-defined positions and subsequently release the cells for quick sample exchange.The developed device also allows simultaneous fluorescence analysis to assess the bacterial viability during atomic force microscope imaging.We demonstrated the potential of our approach for the immobilization of rod-shaped Escherichia coli and Bacillus subtilis.Using our device,we observed buffer-dependent morphological changes of the bacterial envelope mediated by the antimicrobial peptide CM15.Our approach to bacterial immobilization makes sample preparation much simpler and more reliable,thereby accelerating atomic force microscopy studies at the single-cell level.展开更多
基金funding from the European Research Council(ERC)under the European Union’s Horizon 2020 research and innovation program(Project MEMS4.0,ERC-2016-ADG,grant agreement No.742685)the EU’s H2020 framework program for research and innovation under grant agreement n.101007417,NFFA-Europe Pilot Project.M.B.acknowledges the support of SNSF Eccellenza grant No.PCEGP2_194528+4 种基金support from the QuantERA II Programme that has received funding from the European Union’s Horizon 2020 research and innovation program under Grant Agreement No 101017733G.F.and M.P.received funding through the European research council H2020-UE Framework Programme for Research&Innovation(2014-2020)ERC-2017-CoGInCellProject number 773091,and the Swiss National Science Foundation through grant 200021_182562.
文摘Grayscale structured surfaces with nanometer-scale features are used in a growing number of applications in optics and fluidics.Thermal scanning probe lithography achieves a lateral resolution below 10 nm and a vertical resolution below 1 nm,but its maximum depth in polymers is limited.Here,we present an innovative combination of nanowriting in thermal resist and plasma dry etching with substrate cooling,which achieves up to 10-fold amplification of polymer nanopatterns into SiO_(2) without proportionally increasing surface roughness.Sinusoidal nanopatterns in SiO_(2) with 400 nm pitch and 150 nm depth are fabricated free of shape distortion after dry etching.To exemplify the possible applications of the proposed method,grayscale dielectric nanostructures are used for scalable manufacturing through nanoimprint lithography and for strain nanoengineering of 2D materials.Such a method for aspect ratio amplification and smooth grayscale nanopatterning has the potential to find application in the fabrication of photonic and nanoelectronic devices.
基金This work was funded by the Swiss National Science Foundation （Nos.205321_134786, 205320_152675）, and by the European Union FP7/2007-2013/ERC under Grant Agreement No. 307338-NaMic, and Eurostars E!8213.
文摘The atomic force microscope has become an established research tool for imaging microorganisms with unprecedented resolution.However,its use in microbiology has been limited by the difficulty of proper bacterial immobilization.Here,we have developed a microfluidic device that solves the issue of bacterial immobilization for atomic force microscopy under physiological conditions.Our device is able to rapidly immobilize bacteria in well-defined positions and subsequently release the cells for quick sample exchange.The developed device also allows simultaneous fluorescence analysis to assess the bacterial viability during atomic force microscope imaging.We demonstrated the potential of our approach for the immobilization of rod-shaped Escherichia coli and Bacillus subtilis.Using our device,we observed buffer-dependent morphological changes of the bacterial envelope mediated by the antimicrobial peptide CM15.Our approach to bacterial immobilization makes sample preparation much simpler and more reliable,thereby accelerating atomic force microscopy studies at the single-cell level.
