This work was supported by the Natural Science and Engineering Research Council of Canada (Discovery Grant No. 122795-2010) and the program of the Canada Research Chair in Quantum Semiconductors (JJD). The help provided by Xiaohuan Xuang, Mohamed Walid Hassen and technical assistance of Sonia Blais of the Universit&#233; de Sherbrooke Centre de caract&#233;risation de mat&#233;riaux (CCM) in collecting XPS data are greatly appreciated. NL acknowledges the Merit Scholarship Program for Foreign Student, Fonds de recherche du Qu&#233;bec - Nature et technologies, for providing a graduate student scholarship.

1.样品制备<ol><li>使用diamode划线切割的n型（P掺杂）一侧研磨Si晶片（电阻率3.1〜4.8Ω.m），其是3英寸的直径，380微米厚，成12毫米×6毫米的样品;清洁在OptiClear，丙酮和异丙醇（5分钟，每步）的样品。 </li><li>在1分钟以刻蚀掉初始氧化物的〜0.9％的HF溶液蚀刻样本;冲洗在DI水和干的高纯度（99.999％）氮（N 2）。 </li><li>在N 2袋商店准备的样品，以遏制其在空气中氧化。 </li></ol> 2.辐射能力样品的ArF（λ= 193纳米），氟化氪（λ= 248纳米）激光器。 <ol><li>在0.74毫米高腔放置样品，然后密封腔用熔融石英窗口，具有高透射紫外线（≥90％）。用H填充腔室中的0.01-0.2％的范围内，或用脱气甲基2 O 2 / H 2 O的溶液NOL使用微流体通道。 </li><li>照射与均质的ArF或KrF受激光样品以2.6和1.8的缩小，分别。通过一个圆形掩模（4毫米直径）增加激光脉冲100至600中的100个脉冲照射步骤仅2个位点上的每个样品。照射以相同的方式将样品用"枫叶"（9毫米×7.2毫米）掩模。 </li><li>在去离子水冲洗样，干与N 2冲洗;将样品在密闭容器中，然后迅速填补这个容器用 N 2中，为了事先避免暴露在空气中，以进一步的实验。 </li></ol> 3.固定化生物共轭纳米球<ol><li>稀释生物素结合和荧光素染色的40纳米直径的纳米球以pH 7.4的磷酸盐缓冲盐水（PBS，1X）溶液至10 12个粒子/ ml在室温（〜25℃）。浸泡的ArF或KrF激光器照射样品2＆＃160;小时在该溶液中于RT。 </li><li>洗涤样品，用PBS，以消除表面上的物理结合荧光素染色的纳米球。 </li></ol> 4.表面特征<ol><li>接触角（CA）的测量<ol><li>进行静态的CA测量，在室温和环境湿度的环境中的测角器。 </li><li>在微型注射器采用高纯度去离子水（电阻率17.95MΩ·厘米）;产生相似体积（〜5微升）通过降低微型注射器的类似高度对于每个测量滴在样品表面。 </li><li>捕获并保存水滴轮廓的图像由CCD摄像头，支持软件。独立测量4个不同的站点相同的照射条件。 </li><li>估计和平均从ImageJ的软件降分析模块的CA值;加载图像并将其转换为灰度;启动插件Dropsnake;放置一滴轮廓（〜10节）从左上大致几节正确的初始化蛇;接受连接这些结曲线，并按下按钮，蛇的进化曲线。注意:接触角显示的图像和表。 </li></ol></li><li> XPS测量<ol><li>调查表面化学改性与XPS光谱仪（1×10 -9托的基础压力）配备的AlKα源在150瓦工作: <ol><li>加载样品进入真空室。 </li><li>从220微米×220微米的区域收购的50 eV的通能恒定能量模式表面上的调查数据。 </li><li>从相同的分析区域获取高分辨率的扫描数据，在20电子伏特能量通过。 </li></ol></li><li>流程XPS用XPS光谱定量软件光谱数据，参考25,26。 </li></ol></li><li>荧光显微镜成像<ol><li>激发样品，这是通过"枫叶"掩模照射并暴露于荧光素染色纳米微球，用蓝光源（λ= 450〜490纳米）。 </li><li>观察荧光图像，发射在515nm处，在4X的放大荧光倒置显微镜。 </li><li>表征这些样品用原子力显微镜的表面形态，作为参考的27。 </li></ol></li></ol>

The authors have nothing to disclose.

我们提出的Si晶片的紫外激光照射的协议中的微流体腔室填充有H 2 O 2的溶液低浓度以诱导超亲水Si表面，这主要是由于的Si-OH的生成。的H 2 O 2的紫外激光光解被认为以形成负电荷的OH -基团。另外，紫外激光光电效应导致带正电的表面37的形成。因此，这些负OH的相互作用-自由基与带正电的表面导致的Si-OH的生成的表面上。所以，我们可以增?...

显着的电子和化学性能以及它的高机械强度作出硅（Si）为微电子器件和生物医学芯片1的理想选择。在Si表面的选择区域控制已收到显著关注涉及微流体和实验室片上的设备2,3。这通常是获得或者由表面粗糙度的纳米级修饰或通过在表面4的化学处理的应用程序。的表面粗糙化或图案化，以产生在Si表面上无序或有序的表面结构包括光刻法5，离子束光刻6和激光技术7。与这些方法相比，激光表面纹理化工艺被报道是较不复杂的带，以产生微结构以高空间分辨率8的潜力。然而，由于Si具有升高的纹理阈值，要求照射脉冲能量密度，以导致表面纹理超过了其烧蚀阈值（〜500毫焦耳/ 平方厘米）9，硅表面的纹理经常被协助通过采用活性气体环境，如高压六氟化硫环境4,7,8的。因此，要修改的Si表面的润湿性，许多工作已通过沉积有机10和无机膜2，或使用等离子体或电子束的表面处理11,12集中在化学处理。人们认识Si的亲水性从单数和关联的OH基团在其表面上的存在始发可以通过煮沸它在100℃的H 2 O的2溶液数分钟13来实现。然而，所述疏水硅表面状态，其中大部分是由于的Si-H或Si-O-CH 3基团的存在，可以通过湿法化学处理包括用HF酸溶液或涂布有光致抗蚀剂13的蚀刻来实现-15。为了实现硅的润湿性的选择区域的控制，通常需要复杂的构图步骤，其中包括处理化学溶液16。的紫外激光辐射的高化学反应性也被用来选择性区域处理有机膜涂覆固体基材和修改他们的润湿性17。然而，有限的数据量可在Si润湿性通过浸渍在不同的化学溶液的样品照射激光辅助修改。 在我们以前的研究中，第III-V族半导体中的空气18-20和NH 3 21紫外激光照射被成功用于改变砷化镓，砷化铟镓和InP的表面化学组成。我们建立了第III-V族半导体，紫外线激光照射在去离子（DI）水减少表面氧化物和碳化物，而吸附在半导体表面上的水增加了22。一个强疏水性的硅表面（CA〜103°），通过硅样品的ArF激光器照射获得在甲醇中的最近的工作23。如图中箭头X射线光电子能谱（XPS），这主要是由于在ArF激光器的至photodissociate CH 3 OH的能力。我们也使用的KrF或ArF激光照射的Si（001） 在 H 2 O 2在去离子水中的0.01％。这使我们能够实现选择性区域形成的Si超亲水表面（001）的特征在于邻近15°的CA。该XPS结果表明，这是由于产生的的Si-OH键上的照射表面24。 这种新技术的使用的KrF或ArF激光选择性区 Si表面的亲水/疏水表面原位改性的H 2 O 2 / H 2 O和甲醇溶液浓度低的详细说明证明这篇文章。这里提供的细节应该足够让类似的实验，由感兴趣的研究人员进行。

<table><tbody><tr><td>fluorescein stained nanospheres</td><td>Invitrogen</td><td>F8795</td><td></td></tr><tr><td>OptiClear</td><td>National Diagnostics</td><td>OE-101</td><td></td></tr><tr><td>ArF laser (&amp;lambda;=193 nm)</td><td>Lumonics</td><td>pulse master 800</td><td></td></tr><tr><td>KrF laser (&amp;lambda;=248 nm)</td><td>Lumonics</td><td>pulse master 800</td><td></td></tr><tr><td>XPS</td><td>Kratos Analytical</td><td>AXIS Ultra DLD</td><td></td></tr><tr><td>Fluorescence microscope</td><td>Olympus</td><td>IX71</td><td></td></tr><tr><td>XPS quantitification software</td><td>CasaXPS</td><td>2.3.15</td><td></td></tr></tbody></table>

selective area modification of silicon surface wettability by pulsed uv laser irradiation in liquid environment

硅的可润湿性（Si）为在该材料的生物传感装置的制造和表面官能化的技术的重要参数之一。我们报告使用的KrF或ArF激光照射沉浸在与脉冲数低的液体环境中的Si（001）样品，并运行在适度低脉冲能量密度诱导硅润湿性修改的协议。晶圆浸泡长达4小时的0.01％H 2 O 2 / H 2 O解决方案并没有表现出他们的初始接触角（CA）〜75°可衡量的变化。然而，这样的晶片在一个微室500脉冲的KrF或ArF激光照射填充有0.01％ 的 H 2 O 2 / H 2 O的溶液，在250和65毫焦耳/厘米2，分别下降CA以接近15°，表示超亲水表面的形成。 OH-为端的Si（001），形成与晶片的表面形貌的任何可测量的变化，具有已证实通过X射线光电子能谱法和原子力显微镜测量。选择性区域照射样品然后浸入生物素缀合的荧光素染色的纳米球的溶液2小时，从而在非照射区域中的纳米球的一个成功的固定。这说明该方法用于选择性区域biofunctionalization和先进的基于Si的生物传感结构制造的潜力。我们还描述了使用ArF激光器晶片浸渍在甲醇（CH 3 OH）的照射的类似协议在65毫焦耳的脉冲能量密度运行/厘米2和就地形成的Si（001）的强疏水性表面具有103在CA度。该XPS结果表明ArF激光器诱导形成Si-所示的（OCH 3）λ化合物负责观察到的疏水性。但是，没有这样的化合物被发现通过XPS在Si表面上由KrF激光器在甲醇照射，展示出的KrF激光器的无能photodissociate甲醇和创建-OCH 3基团。

这些代表性的成果已经呈现在我们以前发表的作品23,24。 图1显示的网站的CA与N（脉冲数）的DI照射KrF激光器在250毫焦耳/ 平方厘米H 2 O的不同浓度h的2 O 2 / H 2 O的溶液（例如，0.01，0.02，0.05和0.2％）。随着脉冲数的所有的 H 2 O 2的溶液在CA减小。最小的CA（〜15°）为0.02和0.01％的H 2 O 2的溶液中，在500个脉冲获得。一...

Watch this Scientific Journal Video about Selective Area Modification of Silicon Surface Wettability by Pulsed UV Laser Irradiation in Liquid Environment at JoVE.com

Selective Area Modification of Silicon Surface Wettability by Pulsed UV Laser Irradiation in Liquid Environment

我们对在HF原位改变处理的Si（001）面成亲水或疏水状态通过照射在微流体室中填充用H 2 O 2 / H 2 O的溶液（0.01％-0.5％）或甲醇溶液样品的处理报告使用相对低的脉冲能量密度的脉冲UV激光。

硅表面润湿性的选择区域改性脉冲紫外激光照射在液体环境

The wettability of silicon (Si) is one of the important parameters in the technology of surface functionalization of this material and fabrication of ...

selective-area-modification-silicon-surface-wettability-pulsed-uv

Universidad de Cartagena UDEC

Research

JoVE Journal

Engineering

8.2K 次观看.  Université de Sherbrooke. 我们对在HF原位改变处理的Si（001）面成亲水或疏水状态通过照射在微流体室中填充用H 2 O 2 / H 2 O的溶液（0.01％-0.5％）或甲醇溶液样品的处理报告使用相对低的脉冲能量密度的脉冲UV激光。 

视频: Selective Area Modification of Silicon Surface Wettability by Pulsed UV Laser Irradiation in Liquid Environment

A Method of Targeted Cell Isolation via Glass Surface Functionalization

One of the limiting factors to the adoption and advancement of personalized medicine is the inability to develop diagnostic tools to probe individual nuances in expression from patient to patient. Current methodologies that try to separate cells to fill this niche result in disruption of physiological expression, making the separation technique useless as a diagnostic tool. In this protocol, we describe the functionalization and optimization of a surface for the cellular capture and release. This functionalized surface integrates biotinylated antibodies with a glass surface functionalized with an aminosilane (APTES), desthiobiotin and streptavidin. Cell release is facilitated through the introduction of biotin, allowing the recollection and purification of cells captured by the surface. This release is done through the targeting of the secondary moiety desthiobiotin, which results in a much more gentle release paradigm. This reduction in harsh reagents and shear forces reduces changes in cellular expression. The functionalized surface captures up to 80% of cells in a single cell mixture and has demonstrated 50% capture in a dual-cell mixture. Applications of this technology to xenografts and cancer separation studies are investigated. Quantification techniques for surface verification such as plate reader and ImageJ analyses are described as well.

This protocol describes customizable surface functionalization of the desthiobiotin, streptavidin, and APTES system in order to isolate specific cell types of interest. In addition, this manuscript covers the applications, optimization, and verification of this process.

通过玻璃表面功能靶细胞提取方法

One of the limiting factors to the adoption and advancement of personalized medicine is the inability to develop diagnostic tools to probe individual ...

科研

癌症研究

Fabrication of Nano-engineered Transparent Conducting Oxides by Pulsed Laser Deposition

Nanosecond Pulsed Laser Deposition (PLD) in the presence of a background gas allows the deposition of metal oxides with tunable morphology, structure, density and stoichiometry by a proper control of the plasma plume expansion dynamics. Such versatility can be exploited to produce nanostructured films from compact and dense to nanoporous characterized by a hierarchical assembly of nano-sized clusters. In particular we describe the detailed methodology to fabricate two types of Al-doped ZnO (AZO) films as transparent electrodes in photovoltaic devices: 1) at low O2 pressure, compact films with electrical conductivity and optical transparency close to the state of the art transparent conducting oxides (TCO) can be deposited at room temperature, to be compatible with thermally sensitive materials such as polymers used in organic photovoltaics (OPVs); 2) highly light scattering hierarchical structures resembling a forest of nano-trees are produced at higher pressures. Such structures show high Haze factor (&gt;80%) and may be exploited to enhance the light trapping capability. The method here described for AZO films can be applied to other metal oxides relevant for technological applications such as TiO2, Al2O3, WO3 and Ag4O4.

We describe the experimental method to deposit nanostructured oxide thin films by nanosecond Pulsed Laser Deposition (PLD) in the presence of a background gas. By using this method Al-doped ZnO (AZO) films, from compact to hierarchically structured as nano-tree forests, can be deposited.

制备纳米设计的脉冲激光沉积透明导电氧化物

Nanosecond Pulsed  Laser Deposition (PLD) in the presence of a background gas allows the deposition  of metal oxides with tunable morphology, structure, ...

工程学

Soft Lithographic Functionalization and Patterning Oxide-free Silicon and Germanium

The development of hybrid electronic devices relies in large part on the integration of (bio)organic materials and inorganic semiconductors through a stable interface that permits efficient electron transport and protects underlying substrates from oxidative degradation. Group IV semiconductors can be effectively protected with highly-ordered self-assembled monolayers (SAMs) composed of simple alkyl chains that act as impervious barriers to both organic and aqueous solutions. Simple alkyl SAMs, however, are inert and not amenable to traditional patterning techniques. The motivation for immobilizing organic molecular systems on semiconductors is to impart new functionality to the surface that can provide optical, electronic, and mechanical function, as well as chemical and biological activity. 
Microcontact printing (&mu;CP) is a soft-lithographic technique for patterning SAMs on myriad surfaces.1-9 Despite its simplicity and versatility, the approach has been largely limited to noble metal surfaces and has not been well developed for pattern transfer to technologically important substrates such as oxide-free silicon and germanium. Furthermore, because this technique relies on the ink diffusion to transfer pattern from the elastomer to substrate, the resolution of such traditional printing is essentially limited to near 1 &mu;m.10-16
In contrast to traditional printing, inkless &mu;CP patterning relies on a specific reaction between a surface-immobilized substrate and a stamp-bound catalyst. Because the technique does not rely on diffusive SAM formation, it significantly expands the diversity of patternable surfaces. In addition, the inkless technique obviates the feature size limitations imposed by molecular diffusion, facilitating replication of very small (&lt;200 nm) features.17-23 However, up till now, inkless &mu;CP has been mainly used for patterning relatively disordered molecular systems, which do not protect underlying surfaces from degradation.
Here, we report a simple, reliable high-throughput method for patterning passivated silicon and germanium with reactive organic monolayers and demonstrate selective functionalization of the patterned substrates with both small molecules and proteins. The technique utilizes a preformed NHS-reactive bilayered system on oxide-free silicon and germanium. The NHS moiety is hydrolyzed in a pattern-specific manner with a sulfonic acid-modified acrylate stamp to produce chemically distinct patterns of NHS-activated and free carboxylic acids. A significant limitation to the resolution of many &mu;CP techniques is the use of PDMS material which lacks the mechanical rigidity necessary for high fidelity transfer. To alleviate this limitation we utilized a polyurethane acrylate polymer, a relatively rigid material that can be easily functionalized with different organic moieties. Our patterning approach completely protects both silicon and germanium from chemical oxidation, provides precise control over the shape and size of the patterned features, and gives ready access to chemically discriminated patterns that can be further functionalized with both organic and biological molecules. The approach is general and applicable to other technologically-relevant surfaces.

Here we describe a simple method for patterning oxide-free silicon and germanium with reactive organic monolayers and demonstrate functionalization of the patterned substrates with small molecules and proteins. The approach completely protects surfaces from chemical oxidation, provides precise control over feature morphology, and provides ready access to chemically discriminated patterns.

软平版功能化和图案无氧化硅和锗

The development of hybrid electronic devices relies in large part on the integration of (bio)organic materials and inorganic semiconductors through a ...

生物工程

Patterning via Optical Saturable Transitions - Fabrication and Characterization

This protocol describes the fabrication and characterization of nanostructures using a novel nanolithographic technique called Patterning via Optical Saturable Transitions (POST). In this technique the chemical properties of organic photochromic molecules that undergo single-photon reactions are exploited, enabling rapid top-down nanopatterning over large areas at low light intensities, thereby, allowing for the circumvention of the far-field diffraction barrier.4 Simple, cost-effective, high throughput and resolution alternatives to nanopatterning are being explored, such as, two-photon polymerization5,6, beam pen lithography (BPL)7, scanning electron beam lithography (SEBL), and focused ion beam (FIB) patterning. However, multi-photon approaches require high light intensities, which limit their potential for high throughput and offer low image contrast. Although, electron and ion beam lithographic processes offer increased resolution, the serial nature of the process is limited to slow writing speeds, which also prevents patterning of features over large areas. Beam-pen lithography is an approach towards parallel near-field optical lithography. However, the gap between the source of the beam and the surface of the photoresist needs to be controlled extremely precisely for good pattern uniformity and this is very challenging to accomplish for large arrays of beams. Patterning via Optical Saturable Transitions (POST) is an alternative optical nanopatterning technique for patterning sub-wavelength features1-3. Since this technique uses single photons instead of electrons, it is extremely fast and does not require high light intensities1-3, opening the door to massive parallelization.

We report that the diffraction limit of conventional optical lithography can be overcome by exploiting the transitions of organic photochromic derivatives induced by their photoisomerization at low light intensities.1-3 This paper outlines our fabrication technique and two locking mechanisms, namely: dissolution of one photoisomer and electrochemical oxidation.

通过光学吸收跃迁图案 - 制备与表征

This protocol describes the fabrication and characterization of nanostructures using a novel nanolithographic technique called Patterning via Optical ...

Light Enhanced Hydrofluoric Acid Passivation: A Sensitive Technique for Detecting Bulk Silicon Defects

A procedure to measure the bulk lifetime (&#62;100 &#181;sec) of silicon wafers by temporarily attaining a very high level of surface passivation when immersing the wafers in hydrofluoric acid (HF) is presented. By this procedure three critical steps are required to attain the bulk lifetime. Firstly, prior to immersing silicon wafers into HF, they are chemically cleaned and subsequently etched in 25% tetramethylammonium hydroxide. Secondly, the chemically treated wafers are then placed into a large plastic container filled with a mixture of HF and hydrochloric acid, and then centered over an inductive coil for photoconductance (PC) measurements. Thirdly, to inhibit surface recombination and measure the bulk lifetime, the wafers are illuminated at 0.2 suns for 1 min&#160;using a halogen lamp, the illumination is switched off, and a PC measurement is immediately taken. By this procedure, the characteristics of bulk silicon defects can be accurately determined. Furthermore, it is anticipated that a sensitive RT surface passivation technique will be imperative for examining bulk silicon defects when their concentration is low (&#60;1012 cm-3).

A RT liquid surface passivation technique to investigate the recombination activity of bulk silicon defects is described. For the technique to be successful, three critical steps are required: (i) chemical cleaning and etching of silicon, (ii) immersion of silicon in 15% hydrofluoric acid and (iii) illumination for 1 min.

光增强氢氟酸钝化:一个敏感的技术检测散装硅缺陷

A procedure to measure the bulk lifetime (&#62;100 &#181;sec) of silicon wafers by temporarily attaining a very high level of surface passivation when ...

Use of Sacrificial Nanoparticles to Remove the Effects of Shot-noise in Contact Holes Fabricated by E-beam Lithography

Nano-patterns fabricated with extreme ultraviolet (EUV) or electron-beam (E-beam) lithography exhibit unexpected variations in size. This variation has been attributed to statistical fluctuations in the number of photons/electrons arriving at a given nano-region arising from shot-noise (SN). The SN varies inversely to the square root of a number of photons/electrons. For a fixed dosage, the SN is larger in EUV and E-beam lithographies than for traditional (193 nm) optical lithography. Bottom-up and top-down patterning approaches are combined to minimize the effects of shot noise in nano-hole patterning. Specifically, an amino-silane surfactant self-assembles on a silicon wafer that is subsequently spin-coated with a 100 nm film of a PMMA-based E-beam photoresist. Exposure to the E-beam and the subsequent development uncover the underlying surfactant film at the bottoms of the holes. Dipping the wafer in a suspension of negatively charged, citrate-capped, 20 nm gold nanoparticles (GNP) deposits one particle per hole. The exposed positively charged surfactant film in the hole electrostatically funnels the negatively charged nanoparticle to the center of an exposed hole, which permanently fixes the positional registry. Next, by heating near the glass transition temperature of the photoresist polymer, the photoresist film reflows and engulfs the nanoparticles. This process erases the holes affected by SN but leaves the deposited GNPs locked in place by strong electrostatic binding. Treatment with oxygen plasma exposes the GNPs by etching a thin layer of the photoresist. Wet-etching the exposed GNPs with a solution of I2/KI yields uniform holes located at the center of indentations patterned by E-beam lithography. The experiments presented show that the approach reduces the variation in the size of the holes caused by SN from 35% to below 10%. The method extends the patterning limits of transistor contact holes to below 20 nm.

Uniformly sized nanoparticles can remove fluctuations in contact hole dimensions patterned in poly(methyl methacrylate) (PMMA) photoresist films by electron beam (E-beam) lithography. The process involves electrostatic funneling to center and deposit nanoparticles in contact holes, followed by photoresist reflow and plasma- and wet-etching steps.

牺牲纳米颗粒使用删除散粒噪声的影响通过电子束光刻装配式接触孔

Nano-patterns fabricated with extreme ultraviolet (EUV) or electron-beam (E-beam) lithography exhibit unexpected variations in size. This variation has ...

Utilization of Microscale Silicon Cantilevers to Assess Cellular Contractile Function In Vitro

The development of more predictive and biologically relevant in vitro assays is predicated on the advancement of versatile cell culture systems which facilitate the functional assessment of the seeded cells. To that end, microscale cantilever technology offers a platform with which to measure the contractile functionality of a range of cell types, including skeletal, cardiac, and smooth muscle cells, through assessment of contraction induced substrate bending. Application of multiplexed cantilever arrays provides the means to develop moderate to high-throughput protocols for assessing drug efficacy and toxicity, disease phenotype and progression, as well as neuromuscular and other cell-cell interactions. This manuscript provides the details for fabricating reliable cantilever arrays for this purpose, and the methods required to successfully culture cells on these surfaces. Further description is provided on the steps necessary to perform functional analysis of contractile cell types maintained on such arrays using a novel laser and photo-detector system. The representative data provided highlights the precision and reproducible nature of the analysis of contractile function possible using this system, as well as the wide range of studies to which such technology can be applied. Successful widespread adoption of this system could provide investigators with the means to perform rapid, low cost functional studies in vitro, leading to more accurate predictions of tissue performance, disease development and response to novel therapeutic treatment.

Utilization of Microscale Silicon Cantilevers to Assess Cellular Contractile Function In Vitro

This protocol describes the use of microscale silicon cantilevers as pliable culture surfaces for measuring the contractility of muscle cells in vitro. Cellular contraction causes cantilever bending, which can be measured, recorded, and converted into readouts of force, providing a non-invasive and scalable system for measuring contractile function in vitro.

微型硅悬臂梁的利用率，评估细胞收缩功能<em&gt;在体外</em

The development of more predictive and biologically relevant in vitro assays is predicated on the advancement of versatile cell culture systems which ...

Fabricating Reactive Surfaces with Brush-like and Crosslinked Films of Azlactone-Functionalized Block Co-Polymers

In this paper, fabrication methods that generate novel surfaces using the azlactone-based block co-polymer, poly (glycidyl methacrylate)-block-poly (vinyl dimethyl azlactone) (PGMA-b-PVDMA), are presented. Due to the high reactivity of azlactone groups towards amine, thiol, and hydroxyl groups, PGMA-b-PVDMA surfaces can be modified with secondary molecules to create chemically or biologically functionalized interfaces for a variety of applications. Previous reports of patterned PGMA-b-PVDMA interfaces have used traditional top-down patterning techniques that generate non-uniform films and poorly controlled background chemistries. Here, we describe customized patterning techniques that enable precise deposition of highly uniform PGMA-b-PVDMA films in backgrounds that are chemically inert or that have biomolecule-repellent properties. Importantly, these methods are designed to deposit PGMA-b-PVDMA films in a manner that completely preserves azlactone functionality through each processing step. Patterned films show well-controlled thicknesses that correspond to polymer brushes (~90 nm) or to highly crosslinked structures (~1-10 &#956;m). Brush patterns are generated using either the parylene lift-off or interface directed assembly methods described and are useful for precise modulation of overall chemical surface reactivity by adjusting either the PGMA-b-PVDMA pattern density or the length of the VDMA block. In contrast, the thick, crosslinked PGMA-b-PVDMA patterns are obtained using a customized micro-contact printing technique and offer the benefit of higher loading or capture of secondary material due to higher surface area to volume ratios. Detailed experimental steps, critical film characterizations, and trouble-shooting guides for each fabrication method are discussed.

Surface fabrication methods for patterned deposition of nanometer thick brushes or micron thick, crosslinked films of an azlactone block co-polymer are reported. Critical experimental steps, representative results, and limitations of each method are discussed. These methods are useful for creating functional interfaces with tailored physical features and tunable surface reactivity.

Azlactone 功能块共聚物的刷状和交联膜制备反应表面

In this paper, fabrication methods that generate novel surfaces using the azlactone-based block co-polymer, poly (glycidyl methacrylate)-block-poly (vinyl ...

Photopatterning Proteins and Cells in Aqueous Environment Using TiO2 Photocatalysis

Organic contaminants adsorbed on the surface of titanium dioxide (TiO2) can be decomposed by photocatalysis under ultraviolet (UV) light. Here we describe a novel protocol employing the TiO2 photocatalysis to locally alter cell affinity of the substrate surface. For this experiment, a thin TiO2 film was sputter-coated on a glass coverslip, and the TiO2 surface was subsequently modified with an organosilane monolayer derived from octadecyltrichlorosilane (OTS), which inhibits cell adhesion. The sample was immersed in a cell culture medium, and focused UV light was irradiated to an octagonal region. When a neuronal cell line PC12 cells were plated on the sample, cells adhered only on the UV-irradiated area. We further show that this surface modification can also be performed in situ, i.e., even when cells are growing on the substrate. Proper modification of the surface required an extracellular matrix protein collagen to be present in the medium at the time of UV irradiation. The technique presented here can potentially be employed in patterning multiple cell types for constructing coculture systems or to arbitrarily manipulate cells under culture.

Photopatterning Proteins and Cells in Aqueous Environment Using TiO2 Photocatalysis

We describe a protocol for modifying cell affinity of a scaffold surface in aqueous environment. The method takes advantage of titanium dioxide photocatalysis to decompose organic film in the photo-irradiated region. We show that it can be used to create microdomains of scaffolding proteins, both ex situ and in situ.

光图案蛋白质和细胞中的水环境中使用二氧化钛<sub&gt; 2</sub&gt;光催化

Organic contaminants adsorbed on the surface of titanium dioxide (TiO2) can be decomposed by photocatalysis under ultraviolet (UV) light. Here we describe ...

Rendering SiO2/Si Surfaces Omniphobic by Carving Gas-Entrapping Microtextures Comprising Reentrant and Doubly Reentrant Cavities or Pillars

We present microfabrication protocols for rendering intrinsically wetting materials repellent to liquids (omniphobic) by creating gas-entrapping microtextures (GEMs) on them comprising cavities and pillars with reentrant and doubly reentrant features. Specifically, we use SiO2/Si as the model system and share protocols for two-dimensional (2D) designing, photolithography, isotropic/anisotropic etching techniques, thermal oxide growth, piranha cleaning, and storage towards achieving those microtextures. Even though the conventional wisdom indicates that roughening intrinsically wetting surfaces (&#952;o &#60; 90&#176;) renders them even more wetting (&#952;r &#60; &#952;o &#60; 90&#176;), GEMs demonstrate liquid repellence despite the intrinsic wettability of the substrate. For instance, despite the intrinsic wettability of silica &#952;o &#8776; 40&#176; for the water/air system, and &#952;o &#8776; 20&#176; for the hexadecane/air system, GEMs comprising cavities entrap air robustly on immersion in those liquids, and the apparent contact angles for the droplets are &#952;r &#62; 90&#176;. The reentrant and doubly reentrant features in the GEMs stabilize the intruding liquid meniscus thereby trapping the liquid-solid-vapor system in metastable air-filled states (Cassie states) and delaying wetting transitions to the thermodynamically-stable fully-filled state (Wenzel state) by, for instance, hours to months. Similarly, SiO2/Si surfaces with arrays of reentrant and doubly reentrant micropillars demonstrate extremely high contact angles (&#952;r &#8776; 150&#176;&#8211;160&#176;) and low contact angle hysteresis for the probe liquids, thus characterized as superomniphobic. However, on immersion in the same liquids, those surfaces dramatically lose their superomniphobicity and get fully-filled within &#60;1 s. To address this challenge, we present protocols for hybrid designs that comprise arrays of doubly reentrant pillars surrounded by walls with doubly reentrant profiles. Indeed, hybrid microtextures entrap air on immersion in the probe liquids. To summarize, the protocols described here should enable the investigation of GEMs in the context of achieving omniphobicity without chemical coatings, such as perfluorocarbons, which might unlock the scope of inexpensive common materials for applications as omniphobic materials. Silica microtextures could also serve as templates for soft materials.

Rendering SiO2/Si Surfaces Omniphobic by Carving Gas-Entrapping Microtextures Comprising Reentrant and Doubly Reentrant Cavities or Pillars

This work presents microfabrication protocols for achieving cavities and pillars with reentrant and doubly reentrant profiles on SiO2/Si wafers using photolithography and dry etching. Resulting microtextured surfaces demonstrate remarkable liquid repellence, characterized by robust long-term entrapment of air under wetting liquids, despite the intrinsic wettability of silica.

硅表面润湿性的选择区域改性脉冲紫外激光照射在液体环境

摘要

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此视频中的章节

通过玻璃表面功能靶细胞提取方法

制备纳米设计的脉冲激光沉积透明导电氧化物

软平版功能化和图案无氧化硅和锗

通过光学吸收跃迁图案 - 制备与表征

光增强氢氟酸钝化:一个敏感的技术检测散装硅缺陷

牺牲纳米颗粒使用删除散粒噪声的影响通过电子束光刻装配式接触孔

微型硅悬臂梁的利用率，评估细胞收缩功能

Azlactone 功能块共聚物的刷状和交联膜制备反应表面

光图案蛋白质和细胞中的水环境中使用二氧化钛

通过雕刻包含可重入和双重入的腔或柱的气体镶入微纹理来渲染 SiO₂/Si 曲面全功能性

硅表面润湿性的选择区域改性脉冲紫外激光照射在液体环境

摘要

探索更多视频

此视频中的章节

通过玻璃表面功能靶细胞提取方法

制备纳米设计的脉冲激光沉积透明导电氧化物

软平版功能化和图案无氧化硅和锗

通过光学吸收跃迁图案 - 制备与表征

光增强氢氟酸钝化:一个敏感的技术检测散装硅缺陷

牺牲纳米颗粒使用删除散粒噪声的影响通过电子束光刻装配式接触孔

微型硅悬臂梁的利用率，评估细胞收缩功能

Azlactone 功能块共聚物的刷状和交联膜制备反应表面

光图案蛋白质和细胞中的水环境中使用二氧化钛

通过雕刻包含可重入和双重入的腔或柱的气体镶入微纹理来渲染 SiO2/Si 曲面全功能性

通过雕刻包含可重入和双重入的腔或柱的气体镶入微纹理来渲染 SiO₂/Si 曲面全功能性