Ultra-Fast Laser Fabrication of Alumina Micro-Sample Array and High-Throughput Characterization of Microstructure and Hardness

In the light of recent advances in material informatics, there is a great demand for high-throughput approaches of sample fabrication and property characterization. Currently, no high-throughput approach has been demonstrated for the fast sampling of the microstructure and the correlated properties. In this paper, we demonstrate the ultra-fast fabrication of an alumina sample array and the high-throughput hardness characterization of these sample units. The alumina sample array was fabricated using picosecond (PS) laser micromachining and CO2 laser sintering within a short time (i.e., less than a few minutes). After laser sintering, the hardness of these sample units was characterized using micro-indentation, and the microstructure was observed using scanning electron microscopy (SEM). In each sample unit, the microstructure was uniform for the entire top surface and within about 20 µm depth from the top surface. The relative density (RD) and corresponding micro-hardness of the sample units was found to continuously vary over a wide range from 89% RD with 600 kgf/mm2 hardness to 99% RD with 1609 kgf/mm2 hardness. For these laser-sintered samples, the correlation of hardness and relative density of the alumina matched well with the literature reports on sintered alumina obtained using conventional low-throughput furnace sintering experiments.

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Semi-automated high-throughput substrate screening assay for nucleoside kinases

10.33774/chemrxiv-2021-k0w7q ◽

2021 ◽

Author(s):

Katja Hellendahl ◽

Maryke Fehlau ◽

Sebastian Hans ◽

Peter Neubauer ◽

Anke Kurreck

Keyword(s):

High Throughput ◽

Viral Infections ◽

Screening Assay ◽

Liquid Handling ◽

Wide Range ◽

High Throughput Assay ◽

Liquid Handling Robot

Nucleoside kinases (NKs) are key enzymes involved in the in vivo phosphorylation of nucleoside analogues used as drugs to treat cancer or viral infections. Having different specificities, the characterization of NKs is essential for drug design and the production of nucleotide analogues in an in vitro enzymatic process. Therefore, a fast and reliable substrate screening assay for NKs is of great importance. Here, we report the validation of a well-known luciferase-based assay for the detection of NK activity in 96-well plate format. The assay was semi-automated using a liquid handling robot. A good linearity was demonstrated (r² >0.98) in the range of 0 to 500 µM ATP, and it was shown that also alternative phosphate donors like dATP or CTP were accepted by the luciferase. The developed high-throughput assay revealed comparable results to HPLC analysis. The assay was exemplary used for the comparison of the substrate spectra of four nucleoside kinases using 20 (8 natural and 12 modified) substrates. The screening results correlated well with literature data and, additionally, previously unknown substrates were identified for three of the NKs studied. Our results demonstrate that the developed semi-automated high-throughput assay is suitable to identify best performing NKs for a wide range of substrates.

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High-throughput microfluidic characterization of erythrocyte shape and mechanical variability

10.1101/488189 ◽

2018 ◽

Cited By ~ 2

Author(s):

Felix Reichel ◽

Johannes Mauer ◽

Ahmad Ahsan Nawaz ◽

Gerhard Gompper ◽

Jochen Guck ◽

...

Keyword(s):

Mechanical Properties ◽

Red Blood Cells ◽

High Throughput ◽

Blood Cells ◽

Microvascular Blood Flow ◽

Flow Conditions ◽

Wide Range ◽

Single Well ◽

Good Agreement

The motion of red blood cells (RBCs) in microchannels is important for microvascular blood flow and biomedical applications such as blood analysis in microfluidics. The current understanding of the complexity of RBC shapes and dynamics in microchannels is mainly based on several simulation studies, but there are a few systematic experimental investigations. Here, we present a combined study, which systematically characterizes RBC behavior for a wide range of flow rates and channel sizes. Even though simulations and experiments generally show good agreement, experimental observations demonstrate that there is no single well-defined RBC state for fixed flow conditions, but rather a broad distribution of states. This result can be attributed to the inherent variability in RBC mechanical properties, which is confirmed by a model that takes the variation in RBC shear elasticity into account. This represents a significant step toward a quantitative connection between RBC behavior in microfluidic devices and their mechanical properties, which is essential for a high-throughput characterization of diseased cells.Significance StatementThe ability to change shape is crucial for the proper functioning of red blood cells under harsh conditions in the microvasculature, since their shapes strongly affect the flow behavior of whole blood. Our results from simulations and systematic experiments reveal the shapes and dynamics of red blood cells for different flow conditions and channel dimensions, generally in good agreement. However, in the experiments, cells do not exhibit a single well-defined shape for fixed flow conditions. We show that this distribution of shapes can be attributed to the variability in mechanical properties of red blood cells.

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PVD synthesis and high-throughput property characterization of Ni–Fe–Cr alloy libraries

Measurement Science and Technology ◽

10.1088/0957-0233/16/1/007 ◽

2004 ◽

Vol 16 (1) ◽

pp. 46-53 ◽

Cited By ~ 20

Author(s):

A Rar ◽

J J Frafjord ◽

Jason D Fowlkes ◽

E D Specht ◽

P D Rack ◽

...

Keyword(s):

High Throughput ◽

Property Characterization

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Effect of plasma nitriding of austenitic stainless steel produced by direct metal laser sintering

Acta Metallurgica Slovaca ◽

10.36547/ams.27.4.1172 ◽

2021 ◽

Vol 27 (4) ◽

pp. 190-194

Author(s):

Dorina Kovács ◽

Dávid Miklós Kemény

Keyword(s):

Surface Roughness ◽

Raw Materials ◽

Plasma Nitriding ◽

Austenitic Stainless Steels ◽

Laser Sintering ◽

Direct Metal Laser Sintering ◽

Direct Current Plasma ◽

Wide Range ◽

Optical Electron

A special additive manufacturing (AM), called as Direct Metal Laser Sintering (DMLS), is a technology that produces 3D workpieces using a wide range of different metals as raw materials. The aim of current research is to investigate the plasma nitriding effect on the DMLS produced samples. The direct current plasma nitriding treatment was achieved at 440 °C for 4 hours with 75%N2 – 25%H2 gas mixture. Before the treatment, the 316L austenitic stainless steels samples were ground with different methods to modify the surface roughness. Scanning electron microscope (SEM), X-ray diffractometer, glow discharge optical electron spectroscopy, Vickers microhardness tester and potentiodynamic corrosion test were used for the characterization of surface properties. The results demonstrated that the surface roughness did not affect the outcome of the plasma nitriding, but the corrosion resistance increases with the decrease of the surface roughness compared to the untreated 3D sample.

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Accelerated discovery and mechanical property characterization of bioresorbable amorphous alloys in the Mg–Zn–Ca and the Fe–Mg–Zn systems using high-throughput methods

Journal of Materials Chemistry B ◽

10.1039/c9tb01302d ◽

2019 ◽

Vol 7 (35) ◽

pp. 5392-5400 ◽

Cited By ~ 2

Author(s):

Amit Datye ◽

Sebastian Alexander Kube ◽

Devendra Verma ◽

Jan Schroers ◽

Udo D. Schwarz

Keyword(s):

Mechanical Property ◽

High Throughput ◽

Amorphous Alloys ◽

Combinatorial Sputtering ◽

Property Characterization

High throughput discovery of amorphous bioresorbable alloys. Top: combinatorial sputtering setup. Bottom: composition of libraries deposited on silicon (Si) wafers for (a) magnesium (Mg)–zinc (Zn)–calcium (Ca) and the (b) iron (Fe)–Mg–Zn systems.

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Rapid, Refined, and Robust Method for Expression, Purification, and Characterization of Recombinant Human Amyloid-beta M1-42

10.26434/chemrxiv.7725002.v1 ◽

2019 ◽

Author(s):

Priya Prakash ◽

Travis Lantz ◽

Krupal P. Jethava ◽

Gaurav Chopra

Keyword(s):

Amyloid Beta ◽

Western Blots ◽

Force Microscopy ◽

E Coli ◽

Atomic Force ◽

Set Up ◽

Short Time

Amyloid plaques found in the brains of Alzheimer’s disease (AD) patients primarily consists of amyloid beta 1-42 (Ab42). Commercially, Ab42 is synthetized using peptide synthesizers. We describe a robust methodology for expression of recombinant human Ab(M1-42) in Rosetta(DE3)pLysS and BL21(DE3)pLysS competent E. coli with refined and rapid analytical purification techniques. The peptide is isolated and purified from the transformed cells using an optimized set-up for reverse-phase HPLC protocol, using commonly available C18 columns, yielding high amounts of peptide (~15-20 mg per 1 L culture) in a short time. The recombinant Ab(M1-42) forms characteristic aggregates similar to synthetic Ab42 aggregates as verified by western blots and atomic force microscopy to warrant future biological use. Our rapid, refined, and robust technique to purify human Ab(M1-42) can be used to synthesize chemical probes for several downstream in vitro and in vivo assays to facilitate AD research.

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