Automated genomic and proteomic applications on the Biomek NX laboratory automation workstation

This technical paper describes the utilization of a new automated liquid handler from Beckman Coulter, Inc., the Biomek^® NX Laboratory Automation Workstation, for genomic and proteomic applications. For genomic applications, methodology for plasmid DNA purification using Promega Wizard^® SV 96 reagents was developed for the Biomek NX. A single plate of bacterial pellets can be processed to purified plasmid DNA without user interaction after initial setup. DNA quantity and quality were assessed by spectrophotometric analysis, restriction digestion, PCR (The PCR process is covered by patents owned by Roche Molecular Systems, Inc., and F. Hoffman La Roche, Ltd.), and capillary sequencing. Additionally, the plasmid preparation method was used to purify plasmid DNA from bacterial clones isolated in a bacterial two-hybrid screening procedure. In this case, the system quickly and efficiently prepared clones for rapid identification of target sequences. For proteomic applications, His-tag proteins were purified from bacterial cultures in a 96-well plate format. Following purification, a Bradford assay was used to determine the quantitative yields of the His-tag protein products in each of the aliquots from the purified samples. The AD 340 Automated Labware Positioner (ALP), an integrated absorbance reader, was used for absorbance measurements in the Bradford assay. Given the placement of this ALP on the deck of the Biomek NX, the entire process of protein purification and quantitation was performed in a complete walk-away automated format. Results obtained when purifying proteins, from both uninduced and induced bacterial cultures, on the worksurface of the Biomek NX will be described.     

用于微流控制备的3D打印机设计

针对微流控芯片传统加工工艺成本较高,工时较长等问题提出了一种低成本、适用于微流控芯片制备的3D打印机设计方案,该设计方案由3D打印机本体和上位机控制软件组成,其中上位机控制软件负责将事先建好的三维模型进行分析、切片,并生成G-code格式文件;3D打印控制系统负责接收、解析G-code文件及转化为打印机可识别的控制指令以完成物体的快速成型。详细阐述了3D打印机各功能模块的具体实现,给出了测试打印结果,证明该打印机具有成本低、精度高的优点。     

The dispensing well plate: a novel device for nanoliter liquid handling in ultra high-throughput screening

A novel method for massive parallel dispensing of liquids in the nanoliter range has been presented. The proposed DWP method has been studied experimentally using prototypes fabricated by different micromachining techniques. Their dispensing performance was successfully characterized by gravimetric and fluorometric experiments. The DWP prototypes were able to deliver fixed volumes between 43 nL and 50 nL, with a CV as low as 1%, when dispensing an array of 24 droplets simultaneously onto a slide and measuring fluorescence with a biochip reader.The proposed DWP method has been proven to be very accurate, scalable, simple, and robust. A reproducibility of the mean dosage volume of better than 3% has been obtained by gravimetric measurements for all prototypes dispensing aqueous solutions or pure DMSO. The DWP technology, therefore, has the potential to speed up the liquid handling in HTS by a factor of 10 to 100 and reduce reagent consumption by a factor of 10 to 20 in the future. The applicability of the DWP method in an HTS laboratory environment has been demonstrated by performing a miniaturized kinase assay with comparable quality to conventional assay volumes. By the demonstrated miniaturization, the reagent consumption could be reduced by a factor of 20.     

Low-cost,rapid-prototyping of digital microfluidics devices

An innovative and simple microfabrication method for digital microfluidics is presented. In this method, devices are formed from copper substrates or gold compact disks using rapid marker masking to replace photolithography. The new method is capable of forming devices with inter-electrode gaps as small as 50 μm. Saran™ wrap (polyethylene film) and commercial water repellants were used as dielectric and hydrophobic coatings, respectively, to replace commonly used and more expensive materials such as parylene-C and Teflon-AF. Devices formed by the new method enabled single- and two-plate actuation of droplets with volumes of 1–12 μL. Fabricated devices were successfully tested for droplet manipulation, merging and splitting. We anticipate that this fabrication method will bring digital microfluidics within the reach of any laboratory with minimal facilities. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

基于FPGA的可层叠组合式SoC原型系统设计

为解决单片FPGA无法满足复杂SoC原型验证所需逻辑资源的问题,设计了一种可层叠组合式超大规模SoC验证系统。该系统采用了模块化设计,通过互补连接器和JTAG控制电路,支持最多5个原型模块的层叠组合,最多可提供2 500万门逻辑资源。经本系统验证的地面数字电视多媒体广播基带调制芯片(BHDTMBT1006)已成功流片。     

直接金属快速成形中的变形测量系统研制

为了对直接金属快速成形中零件的变形规律进行研究,研制了一个变形测量系统。采用了电感调频式位移传感器,可对零件的变形进行在线或离线测量。通过消息传递机制实现了工作台运动进程与变形数据采集进程之间的通信。采集的数据根据不同分析需求进行输出,可以方便地对零件的变形进行分析研究。     

DNA合成技术与仪器研发进展概述

基因组解读促使生命进入数字化时代,合成生物学赋予人类探索生命本质并改造利用的能力,且在医疗、化工、农业及信息等交叉融合领域实现快速发展.DNA合成是合成生物学的基础性技术,其重要性堪比测序技术对基因组学与精准医学的支撑.该文围绕DNA合成方法、技术路径及仪器研制与产业化进展进行了系统性的分析比较,并结合未来需求,对DN...     

A virtual prototyping system for rapid product development

This paper describes a virtual prototyping (VP) system that integrates virtual reality with rapid prototyping (RP) to create virtual or digital prototypes to facilitate product development. The proposed VP system incorporates two new simulation methodologies, namely the dexel-based and the layer-based fabrication approaches, to simulate the powder-based and the laminated sheet-based RP processes, respectively. The dexel-based approach deposits arrays of solid strips to form a layer, while the layer-based approach directly forms a complete layer by extruding the slice contours. The layer is subsequently stacked up to fabricate a virtual prototype. The simulation approaches resemble the physical fabrication processes of most RP systems, and are therefore capable of accurately representing the geometrical characteristics of prototypes. In addition to numerical quantification of the simulation results, the system also provides stereoscopic visualisation of the product design and its prototype for detailed analyses. Indeed, the original product design may be superimposed on its virtual prototype, so that areas with dimensional errors beyond design limits may be clearly highlighted to facilitate point-to-point analysis of the surface texture and the dimensional accuracy of the prototype. Hence, the key control parameters of an RP process, such as part orientation, layer thickness and hatch space, may be effectively tuned up for optimal fabrication of physical prototypes in subsequent product development. Furthermore, the virtual prototypes can be transmitted via the Internet to customers to facilitate global manufacturing. As a result, both the lead-time and the product development costs can be significantly reduced.     

An integrated system design environment: Concepts and a status report

In the construction of requirements specifications for a given problem, it is generally recommended that overspecification of the problem solution be avoided [1]. Such overspecification tends to distort the functionality required by suggesting implementation concepts at the outset. In order to avoid overspecification, and to provide a support environment to the specifier, a four-stage system design environment is proposed and has been partially implemented over a three-year period. The theoretical basis of this approach is explained in [2]. Our system-level specification language (DODAN) is developed in [3]. Based on this specification language, a prototype (DAA) [4, 5, 6] for supporting the requirements specification stage has been implemented. Our other protype (DARMS) addressing the module specification stage was developed in [7, 8]. In this paper, the current status of the project is described with an emphasis on the requirements specification stage.     

The design and fabrication of autonomous polymer-based surface tension-confined microfluidic platforms

A one-step thick film printing process has been established for patterning hydrophobic polyvinyl chloride (PVC) substrate materials with hydrophilic cellulose acetate. The opposing patterned substrate materials are brought within close proximity utilizing spacer material of defined thickness. The parallel-plate configured devices are capable of supporting autonomous fluid transport through capillarity. Minimum attainable path widths of 313.3 ± 17.9 μm can be achieved utilizing an affordable personal printer for photomask generation. In addition, a theoretical model for this system predicting meniscus position as a function of time and system architecture is posed along with experimental data which is found to be in good agreement with the model. Lastly, the curvature of the surface is approximated and exploited for the determination of the true pressure jump across the curved surface at the gas–liquid interface at all points on a discretized surface. The curvature associated pressure jump results are found to be consistent with the Laplace pressure approximation.

基于GSCCT的族性化学结构筛选方案

以处理族性结构信息的计算机表达式一族性结构紧缩关联表(Generic Structure Compact Connection Table,GSCCT)为基础,拟定了一套检索族性结构的筛选策略,即从GSCCT表中提取出主干环节点的预筛选方案。GSCCT表包含主干结构节点和叶结构节点,主干节点又分为环节点和非环节点两部分。叶结构节点中含有环节点时,将其提升为主干环节点。该结构匹配方法与传统的在原子节点层次上的算法不同,是在紧缩节点的层次上提取关键信息,即提取族性结构中的主要信息一环结构信息(或称指纹信息)进行预筛选,先不考虑非环节点和叶节点,以避免大量枚举。文中详细介绍了筛选思路和筛选功能的实现过程。     

A multi-material virtual prototyping system

This paper proposes a multi-material virtual prototyping system for digital fabrication of heterogeneous prototypes. It consists mainly of a topological hierarchy-sorting algorithm for processing slice contours, and a virtual simulation system for visualisation and optimisation of multi-material layered manufacturing (MMLM) processes. The topological hierarchy-sorting algorithm processes the hierarchy relationship of complex slice contours. It builds a parent-and-child list that defines the containment relationship of the slice contours, and subsequently arranges the contours in an appropriate sequence, which facilitates toolpath planning for MMLM by avoiding redundant tool movements. The virtual simulation system simulates MMLM processes and provides stereoscopic visualisation of the resulting multi-material prototypes for quality analysis and optimisation of the processes.