软光刻技术

本文介绍了国外新出现的微结构制造技术——软光刻技术 ,它提供了一种方便的、有效的和低成本的微米、纳米尺寸微结构的制造方法。讨论了软光刻的几个关键技术 :自组织形成的单层有机膜、弹性模、微印刷技术、再铸模、微传递成模、毛细管成模、溶剂辅助成模。并且阐述了软光刻技术在光刻技术难以实现的拓扑结构、材料以及分子尺寸领域上的应用     

软光刻技术

本文介绍了国外新出现的微结构制造技术－软光刻技术，它提供了一种方便的，有效的和低成本的微米，纳米尺寸微结构的制造方法，讨论了软光刻的几个关键技术：自组织形成的单层有机膜，弹性模，微印刷技术，再铸模，微传递成模，毛细管成模，溶剂辅助成模，并且阐述了办光刻技术在光刻技术难以实现的拓扑结构，材料以及分子尺寸领域上的应用。     

MC3T3-E1成骨细胞在微格式化表面的黏附

细胞在材料表面的黏附对细胞的增殖和分化志重要作用。格式化表面提供了对细胞在基底的空间分布和黏附进行控制的方法。本文利用微制作利用微制作形成的格式模板，分别以微接触转印法和微流道法形成格式化表面，使MC3T3－E1成骨细胞以一定的格式黏附于表面上，在微接触转印法形成的含二氯二甲基硅烷（DMS）的疏水区域和不含DMS的亲水区域相间隔的表面，细胞优先在亲水区域黏附，在微流道法形成的胶原和白蛋白格式化表面，细胞优先黏附于含胶原区域，结果还表明微格式化表面可以用于研究表面的物理化学性质对细胞的黏附等功能的影响。     

生物芯片在肺癌临床诊断中的应用

生物芯片（Biochip）技术是20世纪90年代初期发展起来的一门新兴技术，通过微加工技术制作的生物芯片，可以把成千上万乃至几十万个生命信息集成在一个很小的芯片上，达到对基因、抗原和活体细胞等进行分析和检测的目的。芯片的实质是通过平面微细加工技术构建的微流体分析单元和系统，以实现对细胞、蛋白质、     

组织工程神经支架的研究进展

周围神经损伤在临床上非常多见,周围神经损伤给患者带来了高致残率,并给社会及患者家庭带来了巨大的经济负担.这些都使得周围神经损伤成为全球所面临的严峻的健康问题之一.目前,随着神经组织工程的发展,为临床上神经缺损的修复带来了新的希望.神经支架在修复神经缺损方面具有重要作用,可为神经细胞提供暂时的支持、黏附、生长环境,促进神经缺损的修复.就神经支架的分类、特性、应用及存在的问题和发展趋势作一综述.     

植入式微电子神经信道桥接系统体内无线供电模块设计及实验

植入式微电子神经桥芯片是采用微电子的方法实现脊髓损伤功能恢复的植入式系统。为解决这一系统的供能问题,设计并制作了无线经皮能量传输系统的体内供电模块。该模块包括接收线圈、整流芯片和稳压芯片,其中接收线圈利用印刷电路板(PCB)实现,整流芯片和稳压芯片利用CMOS工艺实现。通过板上芯片封装(COB)技术,将各个部分组成体内供电模块。配合前期制作的发射模块,利用猪皮等动物组织,进行模拟植入情况的包埋式能量传输实验。实验结果表明,尽管动物组织对能量传输效率的影响较大,但体内供电模块仍然可以为后续芯片电路提供1.8 V的工作电压,初步实现了神经桥芯片的供能。     

慢性神经电生理实验中微电极的研究现状

从不同的角度介绍几种目前广泛使用的神经微电极,比较了不同的制作工艺和方法的优缺点,提出了目前慢性微电极记录中仍然存在的问题及可能的解决方案.从手工工艺生产的微电极及其推进系统到利用半导体技术和微加工技术生产的微电极阵列,每一种微电极都为慢性神经电生理实验的发展奠定了重要的基础.     

神经细胞的化学分化

组成神经系统的神经细胞形成错综复杂的网络,此网络在发育期间怎样建立起来以达到神经细胞之间有特异的连接方式,并使彼此之间能传导信息及传导给身体其他组织,这就需要每一神经细胞在其接触处“选择”适合于它与其他细胞特异连接的递质物质。神经细胞(或称神经元)与神经细胞之间,或神经细胞与身体其他组织(如肌和     

组织工程神经支架的研究进展

周围神经损伤在临床上非常多见,周围神经损伤给患者带来了高致残率,并给社会及患者家庭带来了巨大的经济负担.这些都使得周围神经损伤成为全球所面临的严峻的健康问题之一.目前,随着神经组织工程的发展,为临床上神经缺损的修复带来了新的希望.神经支架在修复神经缺损方面具有重要作用,可为神经细胞提供暂时的支持、黏附、生长环境,促进神...     

3D打印器官芯片研究进展

器官芯片是一种将生物体活细胞植入精准设计的微流体芯片内,可特定再现生物体组织器官功能的仿生的微生理系统,在疾病模拟、毒性检测、新药研发、精准医疗等许多方面具有独特应用前景。3D生物打印技术与器官芯片技术相结合制作3D打印器官芯片,可实现芯片制造工艺的简易化和低成本化,同时满足对复杂异质三维微环境的精细需求。综述3D打印器官芯片在打印方式、打印墨水等方面的研究进展,阐述其最新生物医学应用,总结器官芯片结构和功能单元的打印方式和打印墨水,探讨基于现有打印工艺实现器官芯片一体化制造的潜在可行性,概述3D打印器官芯片技术在心、肝、肺、肾、神经、肿瘤等组织和器官结构和功能仿生方面的最新进展,最后展望3D打印器官芯片技术领域的发展趋势和有待解决的关键问题。     

Fabrication of hydrogel microstructures using polymerization controlled by microcontact printing (PCμCP)

Hydrogels are widely applied as functional biomaterials in the diagnostic and therapeutic fields. For example, intelligent hydrogels containing ionic groups (pH responsive) and poly(ethylene glycol) have promising applications as pH responsive materials in the biomedical and pharmaceutical fields. For potential use of hydrogels in micro- and nano devices, methods are needed to fabricate structures of various geometries at the micro- and nano scale. In this work, polymerization controlled by microcontact printing (PCμCP) is utilized, which is a method that uses microcontact printing to spatially define polymerization zones. Specifically, gold surfaces were modified by a hydrophobic thiol self assembled monolayer via microcontact printing and then a hydrophilic prepolymer solution was applied and only spatially occupied the regions confined by the hydrophobic thiol. Subsequently, polymerization reactions were carried out to create hydrogel microstructures. The patterned hydrogel produced using these methods are highly uniform in size and shape, having potential application in the field of biomedical microdevices.     

3D打印技术制备器官芯片的研究现状

器官芯片是一种新兴的体外生物模型,在生物医学领域有重要的应用前景。但是,相关研究的开展通常受限于器官芯片繁琐和昂贵的制备过程。近年来,科研工作者借助3D打印技术,实现器官芯片制备的简易化、低成本化,以及芯片结构复杂化和成型一体化。这一技术的突破,有力推动器官芯片相关研究的发展,为其在生物医学领域的广泛应用提供有力支持。综述3D打印制备器官芯片的研究现状,主要包括器官芯片的发展背景、传统制造方法的局限性、 3D打印器官芯片的技术分类及其生物医学应用。列举5种基于不同成型原理的3D打印方法,归纳比较各方法的工艺特点以及制备器官芯片时的适用范围,探讨3D打印制备肝、肾、血管、心脏等器官芯片的具体实例和效果。最后分析该技术的不足之处, 并展望这一领域的发展趋势。     

Application of luminescent Eu:Gd2O3 nanoparticles to the visualization of protein micropatterns

Nanoparticle phosphors made of lanthanide oxides are a promising new class of tags in biochemistry because of their large Stokes shift, sharp emission spectra, long luminescence lifetime, and good photostability. We demonstrate the application of these nanoparticles to the visualization of protein micropatterns. Luminescent europium-doped gadolinium oxide (Eu:Gd2O3) nanoparticles are synthesized by spray pyrolysis. The size distribution is from 5 to 200 nm. The particles are characterized by means of laser-induced fluorescent spectroscopy and transmission electron microscopy (TEM). The main emission peak is at 612 nm. The nanoparticles are coated with avidin through physical adsorption. biotinylated bovine serum albumin (BSA-b) is patterned on a silicon wafer using a microcontact printing technique. The wafer is then incubated in a solution of avidin-coated nanoparticles. Fluorescent microscopic images reveal that the nanoparticles are organized onto designated area, as defined by the microcontact printing process. The luminescent nanoparticles do not suffer photobleaching during the observation, which demonstrates their suitability as luminescent labels for fluorescence microscopy studies. More detailed studies are preformed using atomic-force microscopy (AFM) at a single nanoparticle level. The specific and the nonspecific binding densities of the particles are qualitatively evaluated.     

Chemical and Topographical Surface Modification for Control of Central Nervous System Cell Adhesion

We describe methods of fine scale chemical and topographical patterning of silicon substrates and the selected attachment and growth of central nervous system cells in culture. We have used lithography and microcontact printing to pattern surfaces with self-assembled monolayers and proteins. Chemical patterns can be created that localize and guide the growth of cells on the surfaces. Self-assembled surface texturing with structures at the tens of nanometers scale and lithographic based methods at the micrometer scale have been used to produce a variety of surface topographical features. These experiments suggest that surface texture at the scale of tens of nanometers to micrometers can influence the attachment of these cells to a surface and can be used as a mechanism of isolating cells to a particular area on a silicon substrate.     

3D打印技术在硬组织领域的应用进展*

[摘要]近年来，随着3D打印技术的不断发展与成熟，其在医学领域的应用大有增长的趋势，国内外不少专家、学者正在进行大量尝试，试图充分应用该技术服务人类的医疗行业。文章就3D打印技术的基本原理、3D打印材料及该技术在医疗领域应用现状作简要描述与说明，使读者对3D打印技术及其在医疗领域的应用有初步了解。     

3D打印技术在骨科康复中的应用

向康复医学、康复治疗学等专业人士介绍3D打印技术,运用此技术制作的矫形器可以达到提高患者日常生活活动能力、减轻功能障碍和减少术后并发症的目的。假肢、义肢可以个性化弥补肢体缺陷、提高器具使用率;辅助器具可以满足患者特定的功能需求,帮助其重新回归家庭和社会,提高器具的使用满意度。本文综述3D打印技术的基础以及在康复领域使用该技术的优势与现阶段存在的问题,并对未来在康复领域的应用进行展望。     

Evaluation of silicon nanoporous membranes and ECM-based microenvironments on neurosecretory cells

Understanding the interactions between microfabricated synthetic interfaces and cultured cells expressing a neuronal phenotype are critical for advancing research in the field of neural engineering such as neural recording and stimulation and neural microdevice interactions with the human brain. Here we explore the integration of these two components for therapeutic applications of neural prostheses. Microfabricated silicon nanoporous membranes were investigated for their effects on survival, proliferation, and differentiation of the well-known PC12 clonal line. Specifically, cell morphology, examined through fluorescence staining, were comparable in many respects on both silicon membrane and widely-used polystyrene culture surfaces. The attachment and differentiation of PC12 cells cultured on collagen and laminin-modified membranes and standard tissue culture surfaces were similar. Lastly, the differentiation response and tyrosine hydroxylase activity of PC12 cells embedded in a type I collagen matrix on experimental membrane substrates while exposed to NGF were significant and indistinguishable from tissue-culture polystyrene (TC-PS) surfaces. Results from this research suggest that microfabricated silicon nanoporous membranes may be useful, biocompatible permselective structures for neuroprosthetic applications and that collagen may be a useful immobilizing matrix for PC12 cells loaded in implantable macroencapsulation devices designed for the treatment of neurodegenerative disorders.     

Biological functionalization and surface micropatterning of polyacrylamide hydrogels

Hydrogels are useful for linking proteins to solid surfaces because their hydrophilic nature and porous structure help them to maintain these labile molecules in the native functional state. We have developed a method for creating surface-patterned, biofunctionalized hydrogels on glass or silicon, using polyacrylamide and the disulfide-containing polyacrylamide crosslinker, bis(acryloyl)cystamine. Treatment with a reducing agent created reactive sulfhydryl (-SH) groups throughout these hydrogels that were readily conjugated to iodoacetyl biotin and streptavidin (SA). Immobilization efficiency was approximately 1-2% of the total potential binding capacity of the hydrogel. Porosity of the hydrogel was not a limiting factor for SA immobilization, as determined using fluorescence confocal microscopy. Rather, steric hindrance due to the binding of SA decreased the effective porosity near the surface of the hydrogel, restricting access to the rest of the gel. Using microcontact printing, we indirectly patterned SA on the surface of the hydrogel, generating well-resolved feature sizes of 2 microm in width. Through repeated rounds of microcontact printing, multiple, adjacent protein patterns were generated on the surface of the hydrogel. Biotinylated immune complexes and lipid vesicles readily bound to SA-functionalized hydrogels, demonstrating the feasibility of using this hydrogel system to generate complex biofunctionalized surfaces.     

3D打印技术在颌面整形外科的应用进展

近年来,3D打印技术已经被广泛地研究并应用于生物医学领域,该技术能够有效地改善整形外科手术方式。本研究基于3D打印技术在颌面整形外科的发展现状,主要对该技术在术前模拟、医学教育、临床应用及假体制作等方面的应用作一综述,归纳了该技术在不同情况下的应用特点、应用范围及其实际应用中的优势,总结了当前3D打印技术在临床应用的新方法,分析了当前该技术的主要困难及其发展方向,并对其发展趋势进行了展望。