Editorial: Focus on Top-Down Proteomics: Technology Advances and Biomedical Applications, Honoring Dr. Ying Ge, Recipient of the 2020 ASMS Biemann Medal

Microgels are hydrogel particles with diameters in the micrometer scale that can be fabricated in different shapes and sizes. Microgels are increasingly used for biomedical applications and for biofabrication due to their interesting features, such as injectability, modularity, porosity and tunability in respect to size, shape and mechanical properties. Fabrication methods of microgels are divided into two categories, following a top-down or bottom-up approach. Each approach has its own advantages and disadvantages and requires certain sets of materials and equipments. In this review, we discuss fabrication methods of both top-down and bottom-up approaches and point to their advantages as well as their limitations, with more focus on the bottom-up approaches. In addition, the use of microgels for a variety of biomedical applications will be discussed, including microgels for the delivery of therapeutic agents and microgels as cell carriers for the fabrication of 3D bioprinted cell-laden constructs. Microgels made from well-defined synthetic materials with a focus on rationally designed ultrashort peptides are also discussed, because they have been demonstrated to serve as an attractive alternative to much less defined naturally derived materials. Here, we will emphasize the potential and properties of ultrashort self-assembling peptides related to microgels.

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Top-down fabrication of shape-controlled, monodisperse nanoparticles for biomedical applications

Advanced Drug Delivery Reviews ◽

10.1016/j.addr.2018.07.006 ◽

2018 ◽

Vol 132 ◽

pp. 169-187 ◽

Cited By ~ 30

Author(s):

Xinxin Fu ◽

Jingxuan Cai ◽

Xiang Zhang ◽

Wen-Di Li ◽

Haixiong Ge ◽

...

Keyword(s):

Biomedical Applications ◽

Top Down ◽

Monodisperse Nanoparticles ◽

Shape Controlled

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Adjusting the length of supramolecular polymer bottlebrushes by top-down approaches

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.17.175 ◽

2021 ◽

Vol 17 ◽

pp. 2621-2628

Author(s):

Tobias Klein ◽

Franka V Gruschwitz ◽

Maren T Kuchenbrod ◽

Ivo Nischang ◽

Stephanie Hoeppener ◽

...

Keyword(s):

Polyethylene Oxide ◽

Biomedical Applications ◽

Supramolecular Polymer ◽

Shear Stresses ◽

Hydrophobic Core ◽

Top Down ◽

Cylindrical Structures ◽

One Dimensional ◽

Polymer Nanostructures ◽

Long Fibers

Controlling the length of one-dimensional (1D) polymer nanostructures remains a key challenge on the way toward the applications of these structures. Here, we demonstrate that top-down processing facilitates a straightforward adjustment of the length of polyethylene oxide (PEO)-based supramolecular polymer bottlebrushes (SPBs) in aqueous solutions. These cylindrical structures self-assemble via directional hydrogen bonds formed by benzenetrisurea (BTU) or benzenetrispeptide (BTP) motifs located within the hydrophobic core of the fiber. A slow transition from different organic solvents to water leads first to the formation of µm-long fibers, which can subsequently be fragmented by ultrasonication or dual asymmetric centrifugation. The latter allows for a better adjustment of applied shear stresses, and thus enables access to differently sized fragments depending on time and rotation rate. Extended sonication and scission analysis further allowed an estimation of tensile strengths of around 16 MPa for both the BTU and BTP systems. In combination with the high kinetic stability of these SPBs, the applied top-down methods represent an easily implementable technique toward 1D polymer nanostructures with an adjustable length in the range of interest for perspective biomedical applications.

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Two-Dimensional Borophene: Properties, Fabrication, and Promising Applications

Research ◽

10.34133/2020/2624617 ◽

2020 ◽

Vol 2020 ◽

pp. 1-23 ◽

Cited By ~ 1

Author(s):

Zhongjian Xie ◽

Xiangying Meng ◽

Xiangnan Li ◽

Weiyuan Liang ◽

Weichun Huang ◽

...

Keyword(s):

Biomedical Applications ◽

2D Materials ◽

Chemical Properties ◽

Two Dimensional ◽

Spatial Structures ◽

Top Down ◽

Bottom Up ◽

Promising Agent ◽

Energy Sensor ◽

Multiple Chemical

Monoelemental two-dimensional (2D) materials (Xenes) aroused a tremendous attention in 2D science owing to their unique properties and extensive applications. Borophene, one emerging and typical Xene, has been regarded as a promising agent for energy, sensor, and biomedical applications. However, the production of borophene is still a challenge because bulk boron has rather intricate spatial structures and multiple chemical properties. In this review, we describe its excellent properties including the optical, electronic, metallic, semiconducting, photoacoustic, and photothermal properties. The fabrication methods of borophene are also presented including the bottom-up fabrication and the top-down fabrication. In the end, the challenges of borophene in the latest applications are presented and perspectives are discussed.

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Applications of Scanning Microscopy in Biomedical Research

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101517 ◽

1968 ◽

Vol 26 ◽

pp. 354-355

Author(s):

T. L. Hayes

Keyword(s):

Information Content ◽

Biomedical Research ◽

Biomedical Applications ◽

Three Dimensional ◽

Dental Enamel ◽

Resolving Power ◽

Whole Mount ◽

Two Parameters ◽

Content Information ◽

Sectioned Tissue

Biomedical applications of the scanning electron microscope (SEM) have increased in number quite rapidly over the last several years. Studies have been made of cells, whole mount tissue, sectioned tissue, particles, human chromosomes, microorganisms, dental enamel and skeletal material. Many of the advantages of using this instrument for such investigations come from its ability to produce images that are high in information content. Information about the chemical make-up of the specimen, its electrical properties and its three dimensional architecture all may be represented in such images. Since the biological system is distinctive in its chemistry and often spatially scaled to the resolving power of the SEM, these images are particularly useful in biomedical research.In any form of microscopy there are two parameters that together determine the usefulness of the image. One parameter is the size of the volume being studied or resolving power of the instrument and the other is the amount of information about this volume that is displayed in the image. Both parameters are important in describing the performance of a microscope. The light microscope image, for example, is rich in information content (chemical, spatial, living specimen, etc.) but is very limited in resolving power.

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How SIMS microscopy can be used in medicine

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100132649 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1602-1603

Author(s):

Philippe Fragu

Keyword(s):

Mass Spectrometry ◽

Biomedical Applications ◽

Secondary Ion Mass Spectrometry ◽

Chemical Elements ◽

Biological Applications ◽

The Past ◽

Potential Source ◽

Secondary Ion ◽

Chemical Integrity ◽

Scientific Endeavour

The identification, localization and quantification of intracellular chemical elements is an area of scientific endeavour which has not ceased to develop over the past 30 years. Secondary Ion Mass Spectrometry (SIMS) microscopy is widely used for elemental localization problems in geochemistry, metallurgy and electronics. Although the first commercial instruments were available in 1968, biological applications have been gradual as investigators have systematically examined the potential source of artefacts inherent in the method and sought to develop strategies for the analysis of soft biological material with a lateral resolution equivalent to that of the light microscope. In 1992, the prospects offered by this technique are even more encouraging as prototypes of new ion probes appear capable of achieving the ultimate goal, namely the quantitative analysis of micron and submicron regions. The purpose of this review is to underline the requirements for biomedical applications of SIMS microscopy.Sample preparation methodology should preserve both the structural and the chemical integrity of the tissue.

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Biomedical applications: Pitfalls in the practice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100169626 ◽

1994 ◽

Vol 52 ◽

pp. 378-379

Author(s):

J. D. Shelburne ◽

Peter Ingram ◽

Victor L. Roggli ◽

Ann LeFurgey

Keyword(s):

Operating Room ◽

Liquid Nitrogen ◽

Lung Tissue ◽

Biomedical Applications ◽

Microprobe Analysis ◽

Tissue Sample ◽

Cellular Level ◽

Tissue Samples ◽

Asbestos Fibers

At present most medical microprobe analysis is conducted on insoluble particulates such as asbestos fibers in lung tissue. Cryotechniques are not necessary for this type of specimen. Insoluble particulates can be processed conventionally. Nevertheless, it is important to emphasize that conventional processing is unacceptable for specimens in which electrolyte distributions in tissues are sought. It is necessary to flash-freeze in order to preserve the integrity of electrolyte distributions at the subcellular and cellular level. Ideally, biopsies should be flash-frozen in the operating room rather than being frozen several minutes later in a histology laboratory. Electrolytes will move during such a long delay. While flammable cryogens such as propane obviously cannot be used in an operating room, liquid nitrogen-cooled slam-freezing devices or guns may be permitted, and are the best way to achieve an artifact-free, accurate tissue sample which truly reflects the in vivo state. Unfortunately, the importance of cryofixation is often not understood. Investigators bring tissue samples fixed in glutaraldehyde to a microprobe laboratory with a request for microprobe analysis for electrolytes.

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