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Microaspirationは、細胞膜に負圧を適用し、明確に定義された圧力に応答して膜の変形能を測定することにより細胞の剛性/変形を推定するためのシンプルで再現性の高い方法を提供します。これは、最初の細胞分裂21その後赤血球1の機械的特性を見るためのメカニズムへの洞察を提供するために、ウニの卵の弾性的性質を特徴づけるためにミッチソンとスワン（1954）によって開...

<table border="1"><tbody><tr><td> 試薬の名称 </td><td> 会社 </td><td> カタログ/モデル番号 </td><td> 注釈 </td></tr><tr><td>サッターピペットプラー</td><td>サターインスツルメンツ</td><td> P-97 </td><td></td></tr><tr><td>マイクロフォージ</td><td>ナリシゲ</td><td> MF-830 </td><td></td></tr><tr><td>倒立蛍光顕微鏡</td><td>ツァイス</td><td> AXIOVERT 200M </td><td>顕微鏡は、好ましく3D/deconvolution機能を装備する必要があります。 </td></tr><tr><td>ビデオカメラ</td><td>ツァイス</td><td> AxioCam MRM </td><td></td></tr><tr><td>画像取得sotware </td><td>ツァイス</td><td> AxioVisionの</td><td></td></tr><tr><td>空気圧トランスデューサ</td><td> BioTekの</td><td> DPM-1B </td><td> DPM1B空変換器のテスターは現在FLUKEことによって見つけることができます。 </td></tr><tr><td>ピペットグラス</tD&gt; <td>リッチランド</td><td>カスタマイズされたガラス</td><td>ピペットは1.2内径と外径1.6を使用してカスタマイズされた。 </td></tr><tr><td> DiIを染料</td><td>インビトロジェン</td><td> D282 </td><td> DMSOによく溶ける</td></tr></tbody></table>

micropipette aspiration of substrate-attached cells to estimate cell stiffness

研究の数が増え、個々の細胞の生体力学的特性は、細胞の増殖、分化、移動および細胞間相互作用を含む複数の細胞機能において重要な役割を果たしていることを示している。細胞のバイオメカニクスの2つの重要なパラメータは、細胞変形や剛性と力を収縮し、生成する細胞の能力である。ここでは、細胞表面にガラスマイクロピペット、マイクロピペット吸引またはMicroaspirationと呼ばれる技術によって適用された負圧に応じて、膜変形の度合いを測定することにより、セルの剛性を推定するために迅速かつ簡単な方法を説明します。 Microaspirationその後、空気圧トランスデューサに接続されており、近くに持って来られる、非常に小さなチップ（細胞または組織サンプルの大きさに応じて2から50μmの直径）でマイクロピペットを作成するためにガラスキャピラリーを引っ張ることによって行われます顕微鏡下で細胞の付近。時ピペットの先端が細胞に触れると、負圧工程は、細胞膜上の明確に定義された圧力を発生させる空気圧トランスデューサによりピペットに適用されます。圧力に応じて、メンブレンをピペット内に吸引され、ピペットにプログレッシブ膜変形または &quot;膜投影&quot;は、時間の関数として測定される。この実験的なアプローチの基本的な原理は、定義された機械的な力に応じて、膜変形の程度は膜剛性の関数であるということです。硬めの膜であり、膜変形と短い定常吸引length.The技術の遅い速度は、単離された両方のサスペンションと、基板に接続された、大規模な細胞小器官内の細胞、およびリポソーム上で実行することができます。 分析は、異なる細胞集団や実験条件の与えられた圧力の下で達成最大の膜の変形を比較することによって行われる。 &quot;剛性係数は、&quot; ESです印加圧力の関数としての膜変形の吸引された長さをプロットすることによりtimated。さらに、データはさらに材料の剛性を特徴づける細胞のヤング率（E）は、最も一般的なパラメータを推定するために分析することができる。真核細胞の細胞膜は膜脂質二重層は、サブ膜細胞骨格によって、それが膜の機械的足場を構成し、変形を支配する細胞骨格であるunderliedされる二成分系とみなすことができることに注意することが重要です携帯封筒の。このアプローチは、したがって、サブ膜細胞骨格の力学的特性をプロービングすることができます。

Watch this Scientific Journal Video about Micropipette Aspiration of Substrate-attached Cells to Estimate Cell Stiffness at JoVE.com

Micropipette Aspiration of Substrate-attached Cells to Estimate Cell Stiffness

ここでは、セルの剛性を測定するために迅速かつ簡単な方法を説明します。このアプローチの一般的な原則は、細胞表面にマイクロピペットを介して適用、明確に定義された負圧に応答して膜の変形を測定することです。この方法は、基板に接続された細胞の生体力学的特性を研究するための強力なツールを提供します。

セルの剛性を推定するために基板に接続された細胞のマイクロピペット吸引

Growing number of studies show that biomechanical properties of individual cells play major roles in multiple cellular functions, including cell ...

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Research

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Bioengineering

19.8K ビュー.  University of Illinois. ここでは、セルの剛性を測定するために迅速かつ簡単な方法を説明します。このアプローチの一般的な原則は、細胞表面にマイクロピペットを介して適用、明確に定義された負圧に応答して膜の変形を測定することです。この方法は、基板に接続された細胞の生体力学的特性を研究するための強力なツールを提供します。

ビデオ: Micropipette Aspiration of Substrate-attached Cells to Estimate Cell Stiffness

Design of a Cyclic Pressure Bioreactor for the Ex Vivo Study of Aortic Heart Valves

The aortic valve, located between the left ventricle and the aorta, allows for unidirectional blood flow, preventing backflow into the ventricle. Aortic valve leaflets are composed of interstitial cells suspended within an extracellular matrix (ECM) and are lined with an endothelial cell monolayer. The valve withstands a harsh, dynamic environment and is constantly exposed to shear, flexion, tension, and compression. Research has shown calcific lesions in diseased valves occur in areas of high mechanical stress as a result of endothelial disruption or interstitial matrix damage1-3. Hence, it is not surprising that epidemiological studies have shown high blood pressure to be a leading risk factor in the onset of aortic valve disease4. 
The only treatment option currently available for valve disease is surgical replacement of the diseased valve with a bioprosthetic or mechanical valve5. Improved understanding of valve biology in response to physical stresses would help elucidate the mechanisms of valve pathogenesis. In turn, this could help in the development of non-invasive therapies such as pharmaceutical intervention or prevention. Several bioreactors have been previously developed to study the mechanobiology of native or engineered heart valves6-9. Pulsatile bioreactors have also been developed to study a range of tissues including cartilage10, bone11 and bladder12. The aim of this work was to develop a cyclic pressure system that could be used to elucidate the biological response of aortic valve leaflets to increased pressure loads. 
The system consisted of an acrylic chamber in which to place samples and produce cyclic pressure, viton diaphragm solenoid valves to control the timing of the pressure cycle, and a computer to control electrical devices. The pressure was monitored using a pressure transducer, and the signal was conditioned using a load cell conditioner. A LabVIEW program regulated the pressure using an analog device to pump compressed air into the system at the appropriate rate. The system mimicked the dynamic transvalvular pressure levels associated with the aortic valve; a saw tooth wave produced a gradual increase in pressure, typical of the transvalvular pressure gradient that is present across the valve during diastole, followed by a sharp pressure drop depicting valve opening in systole. The LabVIEW program allowed users to control the magnitude and frequency of cyclic pressure. The system was able to subject tissue samples to physiological and pathological pressure conditions. This device can be used to increase our understanding of how heart valves respond to changes in the local mechanical environment.

Design of a Cyclic Pressure Bioreactor for the Ex Vivo Study of Aortic Heart Valves

A cyclic pressure bioreactor capable of subjecting heart valve tissue to physiological and pathological pressure conditions has been designed. A LabVIEW program allows users to control pressure magnitude, amplitude and frequency. This device can be used to study the mechanobiology of heart valve tissue or isolated cells.

のための周期的圧力のバイオリアクターの設計生体外で</em大動脈心臓弁の>研究

The aortic valve, located between the left ventricle and the aorta, allows for unidirectional blood flow, preventing backflow into the ventricle. Aortic ...

生物工学

Alginate Microcapsule as a 3D Platform for Propagation and Differentiation of Human Embryonic Stem Cells (hESC) to Different Lineages

Human embryonic stem cells (hESC) are emerging as an attractive alternative source for cell replacement therapy since they can be expanded in culture indefinitely and differentiated to any cell types in the body. Various types of biomaterials have also been used in stem cell cultures to provide a microenvironment mimicking the stem cell niche1-3. The latter is important for promoting cell-to-cell interaction, cell proliferation, and differentiation into specific lineages as well as tissue organization by providing a three-dimensional (3D) environment4 such as encapsulation. The principle of cell encapsulation involves entrapment of living cells within the confines of semi-permeable membranes in 3D cultures2. These membranes allow for the exchange of nutrients, oxygen and stimuli across the membranes, whereas antibodies and immune cells from the host that are larger than the capsule pore size are excluded5. Here, we present an approach to culture and differentiate hESC DA neurons in a 3D microenvironment using alginate microcapsules. We have modified the culture conditions2 to enhance the viability of encapsulated hESC. We have previously shown that the addition of p160-Rho-associated coiled-coil kinase (ROCK) inhibitor, Y-27632 and human fetal fibroblast-conditioned serum replacement medium (hFF-CM) to the 3D platform significantly enhanced the viability of encapsulated hESC in which the cells expressed definitive endoderm marker genes1. We have now used this 3D platform for the propagation of hESC and efficient differentiation to DA neurons. Protein and gene expression analyses after the final stage of DA neuronal differentiation showed an increased expression of tyrosine hydroxylase (TH), a marker for DA neurons, &gt;100 folds after 2 weeks. We hypothesized that our 3D platform using alginate microcapsules may be useful to study the proliferation and directed differentiation of hESC to various lineages. This 3D system also allows the separation of feeder cells from hESC during the process of differentiation and also has potential for immune-isolation during transplantation in the future.

Alginate Microcapsule as a 3D Platform for Propagation and Differentiation of Human Embryonic Stem Cells hESC to Different Lineages

We have optimized a microencapsulation technique as an effective 3D platform for propagation and differentiation of embryonic stem cells to endoderm and dopaminergic (DA) neurons. It also provides an opportunity for immune-isolation of cells from the host during transplantation. This platform can be adapted for other cell types.

異なる系統にヒト胚性幹細胞（hESCの）の伝播との差別化のための3Dプラットフォームとしてのアルギン酸マイクロカプセル

Human embryonic stem cells (hESC) are emerging as an attractive alternative source for cell replacement therapy since they can be expanded in culture ...

Spatio-Temporal Manipulation of Small GTPase Activity at Subcellular Level and on Timescale of Seconds in Living Cells

Dynamic regulation of the Rho family of small guanosine triphosphatases (GTPases) with great spatiotemporal precision is essential for various cellular functions and events1, 2. Their spatiotemporally dynamic nature has been revealed by visualization of their activity and localization in real time3. In order to gain deeper understanding of their roles in diverse cellular functions at the molecular level, the next step should be perturbation of protein activities at a precise subcellular location and timing. 
To achieve this goal, we have developed a method for light-induced, spatio-temporally controlled activation of small GTPases by combining two techniques: (1) rapamycin-induced FKBP-FRB heterodimerization and (2) a photo-caging method of rapamycin. With the use of rapamycin-mediated FKBP-FRB heterodimerization, we have developed a method for rapidly inducible activation or inactivation of small GTPases including Rac4, Cdc424, RhoA4 and Ras5, in which rapamycin induces translocation of FKBP-fused GTPases, or their activators, to the plasma membrane where FRB is anchored. For coupling with this heterodimerization system, we have also developed a photo-caging system of rapamycin analogs. A photo-caged compound is a small molecule whose activity is suppressed with a photocleavable protecting group known as a caging group. To suppress heterodimerization activity completely, we designed a caged rapamycin that is tethered to a macromolecule such that the resulting large complex cannot cross the plasma membrane, leading to virtually no background activity as a chemical dimerizer inside cells6. Figure 1 illustrates a scheme of our system. With the combination of these two systems, we locally recruited a Rac activator to the plasma membrane on a timescale of seconds and achieved light-induced Rac activation at the subcellular level6.

A method for spatio-temporal control of small GTPase activity by light is described. This method is based on rapamycin-induced FKBP-FRB heterodimerization and photo-caging systems. Optimization of light-irradiation enables the spatio-temporally controlled activation of small GTPases at the subcellular level.

生きた細胞の細胞内レベルでの秒のタイムスケールの上に小さなGTPase活性の時空間操作

Dynamic regulation of the Rho family of small guanosine triphosphatases (GTPases) with great spatiotemporal precision is essential for various cellular ...

Development, Expansion, and In vivo Monitoring of Human NK Cells from Human Embryonic Stem Cells (hESCs) and Induced Pluripotent Stem Cells (iPSCs)

We present a method for deriving natural killer (NK) cells from undifferentiated hESCs and iPSCs using a feeder-free approach. This method gives rise to high levels of NK cells after 4 weeks culture and can undergo further 2-log expansion with artificial antigen presenting cells. hESC- and iPSC-derived NK cells developed in this system have a mature phenotype and function. The production of large numbers of genetically modifiable NK cells is applicable for both basic mechanistic as well as anti-tumor studies. Expression of firefly luciferase in hESC-derived NK cells allows a non-invasive approach to follow NK cell engraftment, distribution, and function. We also describe a dual-imaging scheme that allows separate monitoring of two different cell populations to more distinctly characterize their interactions in vivo. This method of derivation, expansion, and dual in vivo imaging provides a reliable approach for producing NK cells and their evaluation which is necessary to improve current NK cell adoptive therapies.

Development, Expansion, and In vivo Monitoring of Human NK Cells from Human Embryonic Stem Cells hESCs and Induced Pluripotent Stem Cells iPSCs

This protocol describes the development, expansion, and in vivo imaging of NK cells derived from hESCs and iPSCs.

開発、展開、および<em生体内で&gt;</em&gt;ヒト胚性幹細胞（ヒトES細胞）からヒトNK細胞のモニタリングとや人工多能性幹細胞（性IPSC）

We present a method for deriving natural killer (NK) cells from undifferentiated hESCs and iPSCs using a feeder-free approach. This method gives rise to ...

Transplantation of Induced Pluripotent Stem Cell-derived Mesoangioblast-like Myogenic Progenitors in Mouse Models of Muscle Regeneration

Patient-derived iPSCs could be an invaluable source of cells for future autologous cell therapy protocols. iPSC-derived myogenic stem/progenitor cells similar to pericyte-derived mesoangioblasts (iPSC-derived mesoangioblast-like stem/progenitor cells: IDEMs) can be established from iPSCs generated from patients affected by different forms of muscular dystrophy. Patient-specific IDEMs can be genetically corrected with different strategies (e.g. lentiviral vectors, human artificial chromosomes) and enhanced in their myogenic differentiation potential upon overexpression of the myogenesis regulator MyoD. This myogenic potential is then assessed in vitro with specific differentiation assays and analyzed by immunofluorescence. The regenerative potential of IDEMs is further evaluated in vivo, upon intramuscular and intra-arterial transplantation in two representative mouse models displaying acute and chronic muscle regeneration. The contribution of IDEMs to the host skeletal muscle is then confirmed by different functional tests in transplanted mice. In particular, the amelioration of the motor capacity of the animals is studied with treadmill tests. Cell engraftment and differentiation are then assessed by a number of histological and immunofluorescence assays on transplanted muscles. Overall, this paper describes the assays and tools currently utilized to evaluate the differentiation capacity of IDEMs, focusing on the transplantation methods and subsequent outcome measures to analyze the efficacy of cell transplantation.

Induced pluripotent stem cell (iPSC)-derived myogenic progenitors are promising candidates for cell therapy strategies to treat muscular dystrophies. This protocol describes transplantation and functional measurements required to evaluate the engraftment and differentiation of iPSC-derived mesoangioblasts (a type of muscle progenitors) in mouse models of acute and chronic muscle regeneration.

筋肉再生のマウスモデルにおける誘導多能性幹細胞由来メソアンジオ芽細胞様筋原性前駆細胞の移植

Patient-derived iPSCs could be an invaluable source of cells for future autologous cell therapy protocols. iPSC-derived myogenic stem/progenitor cells ...

Ordering Single Cells and Single Embryos in 3D Confinement: A New Device for High Content Screening

Biological cells are usually observed on flat (2D) surfaces. This condition is not physiological, and phenotypes and shapes are highly variable. Screening based on cells in such environments have therefore serious limitations: cell organelles show extreme phenotypes, cell morphologies and sizes are heterogeneous and/or specific cell organelles cannot be properly visualized. In addition, cells in vivo are located in a 3D environment; in this situation, cells show different phenotypes mainly because of their interaction with the surrounding extracellular matrix of the tissue. In order to standardize and generate order of single cells in a physiologically-relevant 3D environment for cell-based assays, we report here the microfabrication and applications of a device for in vitro 3D cell culture. This device consists of a 2D array of microcavities (typically 105 cavities/cm2), each filled with single cells or embryos. Cell position, shape, polarity and internal cell organization become then normalized showing a 3D architecture. We used replica molding to pattern an array of microcavities, &#8216;eggcups&#8217;, onto a thin polydimethylsiloxane (PDMS) layer adhered on a coverslip. Cavities were covered with fibronectin to facilitate adhesion. Cells were inserted by centrifugation. Filling percentage was optimized for each system allowing up to 80%. Cells and embryos viability was confirmed. We applied this methodology for the visualization of cellular organelles, such as nucleus and Golgi apparatus, and to study active processes, such as the closure of the cytokinetic ring during cell mitosis. This device allowed the identification of new features, such as periodic accumulations and inhomogeneities of myosin and actin during the cytokinetic ring closure and compacted phenotypes for Golgi and nucleus alignment. We characterized the method for mammalian cells, fission yeast, budding yeast, C. elegans with specific adaptation in each case. Finally, the characteristics of this device make it particularly interesting for drug screening assays and personalized medicine.

We report a device and a new method to study cells and embryos. Single cells are precisely ordered in microcavity arrays. Their 3D confinement is a step towards 3D environments encountered in physiological conditions and allows organelle orientation. By controlling cell shape, this setup minimizes variability reported in standard assays.

シングルセルおよび3D閉じ込めにおける単一胚を注文：ハイコンテントスクリーニングのための新しいデバイスを

Biological cells are usually observed on flat (2D) surfaces. This condition is not physiological, and phenotypes and shapes are highly variable. Screening ...

Simple Polyacrylamide-based Multiwell Stiffness Assay for the Study of Stiffness-dependent Cell Responses

Currently, most of the in vitro cell research is performed on rigid tissue culture polystyrene (~1 GPa), while most cells in the body are attached to a matrix that is elastic and much softer (0.1 &#8211; 100 kPa). Since such stiffness mismatch greatly affects cell responses, there is a strong interest in developing hydrogel materials that span a wide range of stiffness to serve as cell substrates. Polyacrylamide gels, which are inexpensive and cover the stiffness range of all soft tissues in the body, are the hydrogel of choice for many research groups. However, polyacrylamide gel preparation is lengthy, tedious, and only suitable for small batches. Here, we describe an assay which by utilizing a permanent flexible plastic film as a structural support for the gels, enables the preparation of polyacrylamide gels in a multiwell plate format. The technique is faster, more efficient, and less costly than current methods and permits the preparation of gels of custom sizes not otherwise available. As it doesn&#8217;t require any specialized equipment, the method could be easily adopted by any research laboratory and would be particularly useful in research focused on understanding stiffness-dependent cell responses.

Here, a method that enables quick, efficient, and inexpensive preparation of polyacrylamide gels in a multiwell plate format is described. The method does not require any specialized equipment and could be easily adopted by any research laboratory. It would be particularly useful in research focused on understanding stiffness-dependent cell responses.

剛性依存性細胞応答の研究のための簡単​​なポリアクリルアミド系マルチウェル剛性アッセイ

Currently, most of the in vitro cell research is performed on rigid tissue culture polystyrene (~1 GPa), while most cells in the body are attached to a ...

A Method to Estimate Cadaveric Femur Cortical Strains During Fracture Testing Using Digital Image Correlation

This protocol describes the method using digital image correlation to estimate cortical strain from high speed video images of the cadaveric femoral surface obtained from mechanical testing. This optical method requires a texture of many contrasting fiduciary marks on a solid white background for accurate tracking of surface deformation as loading is applied to the specimen. Immediately prior to testing, the surface of interest in the camera view is painted with a water-based white primer and allowed to dry for several minutes. Then, a black paint is speckled carefully over the white background with special consideration for the even size and shape of the droplets. Illumination is carefully designed and set such that there is optimal contrast of these marks while minimizing reflections through the use of filters. Images were obtained through high speed video capture at up to 12,000 frames/s. The key images prior to and including the fracture event are extracted and deformations are estimated between successive frames in carefully sized interrogation windows over a specified region of interest. These deformations are then used to compute surface strain temporally during the fracture test. The strain data is very useful for identifying fracture initiation within the femur, and for eventual validation of proximal femur fracture strength models derived from Quantitative Computed Tomography-based Finite Element Analysis (QCT/FEA).

In this protocol, the femur surface strains are estimated during fracture testing using the digital image correlation technique. The novelty of the method involves application of a high-contrast stochastic speckle pattern on the femur surface, carefully specified illumination, high speed video capture, and digital image correlation analysis for strain calculations.

破壊を使用してデジタル画像相関法を試験中に死体大腿骨皮質系統を推定する方法

This protocol describes the method using digital image correlation to estimate cortical strain from high speed video images of the cadaveric femoral ...

Human Pluripotent Stem Cell Culture on Polyvinyl Alcohol-Co-Itaconic Acid Hydrogels with Varying Stiffness Under Xeno-Free Conditions

The effect of physical cues, such as the stiffness of biomaterials on the proliferation and differentiation of stem cells, has been investigated by several researchers. However, most of these investigators have used polyacrylamide hydrogels for stem cell culture in their studies. Therefore, their results are controversial because those results might originate from the specific characteristics of the polyacrylamide and not from the physical cue (stiffness) of the biomaterials. Here, we describe a protocol for preparing hydrogels, which are not based on polyacrylamide, where various stem, cells including human embryonic stem (ES) cells and human induced pluripotent stem (iPS) cells, can be cultured. Hydrogels with varying stiffness were prepared from bioinert polyvinyl alcohol-co-itaconic acid (P-IA), with stiffness controlled by crosslinking degree by changing crosslinking time. The P-IA hydrogels grafted with and without oligopeptides derived from extracellular matrix were investigated as a future platform for stem cell culture and differentiation. The culture and passage of amniotic fluid stem cells, adipose-derived stem cells, human ES cells, and human iPS cells is described in detail here. The oligopeptide P-IA hydrogels showed superior performances, which were induced by their stiffness properties. This protocol reports the synthesis of the biomaterial, their surface manipulation, along with controlling the stiffness properties and finally, their impact on stem cell fate using xeno-free culture conditions. Based on recent studies, such modified substrates can act as future platforms to support and direct the fate of various stem cells line to different linkages; and further, regenerate and restore the functions of the lost organ or tissue.

A protocol is presented to prepare polyvinyl alcohol-co-itaconic acid hydrogels with varying stiffness, which were grafted with and without oligopeptides, to investigate the effect of the stiffness of biomaterials on the differentiation and proliferation of stem cells. The stiffness of the hydrogels was controlled by the crosslinking time.

Xeno 無料条件下におけるさまざまな剛性とポリビニル アルコール Co イタコン酸ゲルのひと多能性幹細胞文化

The effect of physical cues, such as the stiffness of biomaterials on the proliferation and differentiation of stem cells, has been investigated by ...

Stiffness Measurement of Soft Silicone Substrates for Mechanobiology Studies Using a Widefield Fluorescence Microscope

Soft tissues in the human body typically have stiffness in the kilopascal (kPa) range. Accordingly, silicone and hydrogel flexible substrates have been proven to be useful substrates for culturing cells in a physical microenvironment that partially mimics in vivo conditions. Here, we present a simple protocol for characterizing the Young's moduli of isotropic linear elastic substrates typically used for mechanobiology studies. The protocol consists of preparing a soft silicone substrate on a Petri dish or stiff silicone, coating the top surface of the silicone substrate with fluorescent beads, using a millimeter-scale sphere to indent the top surface (by gravity), imaging the fluorescent beads on the indented silicone surface using a fluorescence microscope, and analyzing the resultant images to calculate the Young's modulus of the silicone substrate. Coupling the substrate's top surface with a moduli extracellular matrix protein (in addition to the fluorescent beads) allows the silicone substrate to be readily used for cell plating and subsequent studies using traction force microscopy experiments. The use of stiff silicone, instead of a Petri dish, as the base of the soft silicone, enables the use of mechanobiology studies involving external stretch. A specific advantage of this protocol is that a widefield fluorescence microscope, which is commonly available in many labs, is the major equipment necessary for this procedure. We demonstrate this protocol by measuring the Young's modulus of soft silicone substrates of different elastic moduli.

Substrates with stiffness in the kilopascal-range are useful to study the response of cells to physiologically relevant micro-environment stiffness. Using just a widefield fluorescence microscope, the Young's modulus of soft silicone gels can be determined using an indentation with a suitable sphere.

広視野蛍光顕微鏡を用いたメカノバイオロジー研究の柔らかいシリコーン基板の剛性測定

Soft tissues in the human body typically have stiffness in the kilopascal (kPa) range. Accordingly, silicone and hydrogel flexible substrates have been ...