Expansion microscopy Chen, Fei; Tillberg, Paul W.; Boyden, Edward S.
Science (American Association for the Advancement of Science),
01/2015, Letnik:
347, Številka:
6221
Journal Article
Recenzirano
Odprti dostop
In optical microscopy, fine structural details are resolved by using refraction to magnify images of a specimen. We discovered that by synthesizing a swellable polymer network within a specimen, it ...can be physically expanded, resulting in physical magnification. By covalently anchoring specific labels located within the specimen directly to the polymer network, labels spaced closer than the optical diffraction limit can be isotropically separated and optically resolved, a process we call expansion microscopy (ExM). Thus, this process can be used to perform scalable superresolution microscopy with diffraction-limited microscopes. We demonstrate ExM with apparent ∼70-nanometer lateral resolution in both cultured cells and brain tissue, performing three-color superresolution imaging of ∼107 cubic micrometers of the mouse hippocampus with a conventional confocal microscope.
Fabricating ultrathin two-dimensional (2D) covalent organic framework (COF) nanosheets (NSs) in large scale and high yield still remains a great challenge. This limits the exploration of the unique ...functionalities and wide range of application potentials of such materials. Herein, we develop a scalable general bottom-up approach to facilely synthesize ultrathin (<2.1 nm) imine-based 2D COF NSs (including COF-366 NSs, COF-367 NSs, COF-367-Co NSs, TAPB-PDA COF NSs, and TAPB-BPDA COF NSs) in large scale (>100 mg) and high yield (>55%), via an imine-exchange synthesis strategy through adding large excess amounts of 2,4,6-trimethylbenzaldehyde into the reaction system under solvothermal conditions. Impressively, visualization of the periodic pore lattice for COF-367 NSs by a scanning tunneling microscope (STM) clearly discloses the ultrathin 2D COF nature. In particular, the ultrathin COF-367-Co NSs isolated are subject to the heterogeneous photocatalyst for CO2-to-CO conversion, showing excellent efficiency with a CO production rate as high as 10 162 μmol g–1 h–1 and a selectivity of ca. 78% in aqueous media under visible-light irradiation, far superior to corresponding bulk materials and comparable with the thus far reported state-of-the-art visible-light driven heterocatalysts.
Mikroskop cahaya dapat digunakan untuk melakukan magnifikasi dan melihat objek mikroskopis seperti bakteri, virus, atau sel untuk tujuan diagnosis suatu penyakit. Dalam melakukan pengamatan ...berdasarkan jumlah sampel yang banyak, ahli laboratorium rentan terhadap kelelahan, kesalahan, dan subjektivitas pengamatan. Oleh karena itu, kamera digital, komputer mini raspberry pi, layar liquid crystal display (LCD), motor stepper, catu daya dan bahasa pemrograman python digunakan sebagai komponen pendukung mikroskop cahaya untuk mengakusisi sampel laboratorium yang diamati dalam format digital sehingga dapat dilakukan operasi pengolahan citra pada raspberry pi dan ditampilkan hasilnya di layar LCD. Sedangkan motor stepper dan driver motor digunakan untuk menggeser meja sampel secara otomatis. Semua proses ini dilakukan dengan menggunakan bahasa pemrograman python. Hal ini dilakukan dengan tujuan untuk mengurangi beban pengamat dalam melihat dan menggeser slide sampel sebanyak 100 kali. Sistem akuisisi citra digital dan penggeseran meja sampel otomatis ini dirancang pada mikroskop cahaya portabel mampu meng-capture sampel pada kaca preparat menjadi citra digital, menggeser kaca preparat 100 kali, dan dilengkapi dengan catu daya 220 Volt sehingga dapat digunakan di fasilitas kesehatan manapun di Indonesia. Mikroskop digital, otomatis, dan portabel berbasis platform komputer mini raspberry pi ini dapat digunakan untuk melakukan pemeriksaan laboratorium berbagai penyakit seperti tuberculosis, malaria, atau leukimia dengan efisien dan efektif sehingga dapat mempermudah proses diagnosis penyakit dan dapat meningkatkan layanan kesehatan di berbagai daerah di Indonesia dan berkontribusi dalam penurunan dan eliminasi berbagai penyakit.
The Zeiss Airyscan microscope transforms a diffraction-limited, point-scanning confocal microscope into a super-resolution microscope using a specialized 32-channel Airyscan detector. By improving ...resolution twofold and signal-to-noise ratio eightfold relative to conventional confocal microscopes while retaining confocal functionality, the Airyscan microscope has become a very popular super-resolution imaging tool for cell biologists. In this chapter, we describe the fundamentals of Airyscan imaging, with the aim of helping the reader determine the proper acquisition settings for different types of experiments, optimize imaging conditions, and process the raw Airyscan images to obtain final images with the best quality. We also provide some tips, tricks, and best practices for Airyscan imaging. Of note, while our focus is on the Airyscan function of this microscope rather than its conventional confocal function, the Airyscan unit comes as an add-on to the conventional Zeiss laser scanning confocal microscope. This protocol is for the first generation Airyscan Zeiss 800 series microscope.
By using an oriented electric field in a scanning tunneling microscope, one can locally control the condensation of boronic acids at the liquid/solid interface. The phase transition between ...self-assembled molecular networks and covalent organic frameworks is controlled by changing the polarity of the applied bias. The electric-field-induced phase transformation is reversible under ambient conditions.
Compositional engineering of a mixed cation/mixed halide perovskite in the form of (FAPbI3)0.85(MAPbBr3)0.15 is one of the most effective strategies to obtain record-efficiency perovskite solar ...cells. However, the perovskite self-organization upon crystallization and the final elemental distribution, which are paramount for device optimization, are still poorly understood. Here we map the nanoscale charge carrier and elemental distribution of mixed perovskite films yielding 20% efficient devices. Combining a novel in-house-developed high-resolution helium ion microscope coupled with a secondary ion mass spectrometer (HIM-SIMS) with Kelvin probe force microscopy (KPFM), we demonstrate that part of the mixed perovskite film intrinsically segregates into iodide-rich perovskite nanodomains on a length scale of up to a few hundred nanometers. Thus, the homogeneity of the film is disrupted, leading to a variation in the optical properties at the micrometer scale. Our results provide unprecedented understanding of the nanoscale perovskite composition.
This review commemorates the 40th anniversary of DNA sequencing, a period in which we have already witnessed multiple technological revolutions and a growth in scale from a few kilobases to the first ...human genome, and now to millions of human and a myriad of other genomes. DNA sequencing has been extensively and creatively repurposed, including as a 'counter' for a vast range of molecular phenomena. We predict that in the long view of history, the impact of DNA sequencing will be on a par with that of the microscope.
The internal vibrations of molecules drive the structural transformations that underpin chemistry and cellular function. While vibrational frequencies are measured by spectroscopy, the normal modes ...of motion are inferred through theory because their visualization would require microscopy with ångström-scale spatial resolution-nearly three orders of magnitude smaller than the diffraction limit in optics
. Using a metallic tip to focus light and taking advantage of the surface-enhanced Raman effect
to amplify the signal from individual molecules, tip-enhanced Raman spectromicroscopy (TER-SM)
reaches the requisite sub-molecular spatial resolution
, confirming that light can be confined in picocavities
and anticipating the direct visualization of molecular vibrations
. Here, by using TER-SM at the precisely controllable junction of a cryogenic ultrahigh-vacuum scanning tunnelling microscope
, we show that ångström-scale resolution is attained at subatomic separation between the tip atom and a molecule in the quantum tunnelling regime of plasmons
. We record vibrational spectra within a single molecule, obtain images of normal modes and atomically parse the intramolecular charges and currents driven by vibrations. Our analysis provides a paradigm for optics in the atomistic near-field.
The nanoscale control afforded by scanning probe microscopes has prompted the development of a wide variety of scanning-probe-based patterning methods. Some of these methods have demonstrated a high ...degree of robustness and patterning capabilities that are unmatched by other lithographic techniques. However, the limited throughput of scanning probe lithography has prevented its exploitation in technological applications. Here, we review the fundamentals of scanning probe lithography and its use in materials science and nanotechnology. We focus on robust methods, such as those based on thermal effects, chemical reactions and voltage-induced processes, that demonstrate a potential for applications.
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