期刊
ACS NANO
卷 12, 期 11, 页码 11458-11470出版社
AMER CHEMICAL SOC
DOI: 10.1021/acsnano.8b06489
关键词
solid-state nanopore; dielectric breakdown; nanofabrication; lipid bilayer coating protein characterization; surface functionalization; laser heating
类别
资金
- Swiss National Science Foundation (SNSF) [200021_169304]
- National Science Foundation
- Oxford Nanopore Technologies [350509-N016133]
Nanopores with diameters from 20 to 50 nm in silicon nitride (SiNx) windows are useful for single-molecule studies of globular macromolecules. While controlled breakdown (CBD) is gaining popularity as a method for fabricating nanopores with reproducible size control and broad accessibility, attempts to fabricate large nanopores with diameters exceeding similar to 20 nm via breakdown often result in undesirable formation of multiple nanopores in SiNx membranes. To reduce the probability of producing multiple pores, we combined two strategies: laser-assisted breakdown and controlled pore enlargement by limiting the applied voltage. Based on laser power-dependent increases in nanopore conductance upon illumination and on the absence of an effect of ionic strength on the ratio between the nanopore conductance before and after laser illumination, we suggest that the increased rate of controlled breakdown results from laser-induced heating. Moreover, we demonstrate that conductance values before and after coating the nanopores with a fluid lipid bilayer can indicate fabrication of a single nanopore versus multiple nanopores. Complementary flux measurements of Ca2+ through the nanopore typically confirmed assessments of single or multiple nanopores that we obtained using the coating method. Finally, we show that thermal annealing of CBD pores significantly increased the success rate of coating and reduced the current noise before and after lipid coating. We characterize the geometry of these nanopores by analyzing individual resistive pulses produced by translocations of spherical proteins and demonstrate the usefulness of these nanopores for estimating the approximate molecular shape of IgG proteins.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据