基因/蛋白质组学技术在生物材料生物相容性研究中的应用

生物材料的生物相容性是生物材料研究领域的关键科学问题。分子生物学技术的发展使生物材料的生物相容性评价从动物水平和细胞水平深入到分子水平。生物组学技术的发展为高通量进行生物材料分子生物相容性评价、阐明生物材料与生物体的相互作用机理提供了有效的手段。本文综述了生物材料生物相容性研究现状及基因组学、蛋白质组学技术在生物材料生物相容性研究中的应用。     

单片集成低功耗神经信号检测CMOS放大器

采用CSMC 0.6μm CMOS工艺设计了可用于植入式神经信号检测的放大器芯片.电路适用于卡肤电极系统,包括低噪声前置放大级、由电流模仪表放大器构成的主放大级、输出缓冲级和恒跨导偏置级.电路工作于2.5V/±1.25V,功耗180μW.为满足体内植入式神经信号检测的要求,通过电路改进以避免使用片外元件,实现了单片集成.根据神经信号的特点,电路频率响应带宽设计为59Hz～12.8kHz,增益80dB.采用时域方法测试,芯片达到设计目标,有望用于体内神经信号检测.依据测试结果分析了电路特性并提出改进方法.     

Microelectronic neural bridge for signal regeneration and function rebuilding over two separate nerves

According to the feature of neural signals,a micro-electronic neural bridge(MENB)has been designed. It consists of two electrode arrays for neural signal detection and functional electrical stimulation(FES),and a microelectronic circuit for signal amplifying,processing,and FES driving.The core of the system is realized in 0.5-μm CMOS technology and used in animal experiments.A special experimental strategy has been designed to demonstrate the feasibility of the system.With the help of the MENB,the withdrawal reflex function of the left/right leg of one spinal toad has been rebuilt in the corresponding leg of another spinal toad.According to the coherence analysis between the source and regenerated neural signals,the controlled spinal toad’s sciatic nerve signal is delayed by 0.72 ms in relation to the sciatic nerve signal of the source spinal toad and the cross-correlation function reaches a value of 0.73.This shows that the regenerated signal is correlated with the source sciatic signal significantly and the neural activities involved in reflex function have been regenerated.The experiment demonstrates that the MENB is useful in rebuilding the neural function between nerves of different bodies.     

纳米金与细胞相互作用机理的蛋白质组学研究

应用蛋白质组学结合生物信息学方法研究纳米金与人皮肤成纤维细胞(HDF-f )的作用机理.首先采用柠檬酸钠还原氛金酸法制备20nm的纳米金,然后应用MTT法和流式细胞术评价纳米金的细胞毒性及对细胞周期和细胞凋亡的影响.接着应用蛋白质组学技术和生物信息学方法筛选纳米金作用后细胞发生差异表达的蛋白质并进行基因本体论分析.MT...     

生物电子学领域中的生物材料与生物相容性研究

生物电子学是一门涉及生物学、电子学、化学、物理、材料及信息技术等许多学科的交叉学科,生物电子学发展中的一些科学问题直接与生物材料及其生物相容性研究有关。从生物电子学的概念出发,从微电子植入器件、植入器件相关电极制造技术及表面改性、体外神经芯片表面修饰与改性3个方面,结合本实验室的相关研究工作,讨论了生物电子学领域中的生物材料与生物相容性研究进展,指出了生物材料和生物电子学的交叉是未来科学发展的必然趋势。     

生物电子学领域中的生物材料与生物相容性研究

生物电子学是一门涉及生物学、电子学、化学、物理、材料及信息技术等许多学科的交叉学科,生物电子学发展中的一些科学问题直接与生物材料及其生物相容性研究有关。从生物电子学的概念出发,从微电子植入器件、植入器件相关电极制造技术及表面改性、体外神经芯片表面修饰与改性3个方面,结合本实验室的相关研究工作,讨论了生物电子学领域中的生物材料与生物相容性研究进展,指出了生物材料和生物电子学的交叉是未来科学发展的必然趋势。     

一种用于中枢神经信号再生的四通道微电子系统

This paper presents a microelectronic system which is capable of making a signal record and functional electric stimulation of an injured spinal cord. As a requirement of implantable engineering for the regeneration microelectronic system, the system is of low noise, low power, small size and high performance. A front-end circuit and two high performance OPAs （operational amplifiers） have been designed for the system with different functions, and the two OPAs are a low-noise low-power two-stage OPA and a constant-gm RTR input and output OPA. The system has been realized in CSMC 0.5-μm CMOS technology. The test results show that the system satisfies the demands of neuron signal regeneration.     

单片集成低功耗神经信号检测CMOS放大器

采用CSMC 0.6μm CMOS工艺设计了可用于植入式神经信号检测的放大器芯片.电路适用于卡肤电极系统,包括低噪声前置放大级、由电流模仪表放大器构成的主放大级、输出缓冲级和恒跨导偏置级.电路工作于2.5V/±1.25V,功耗180μW.为满足体内植入式神经信号检测的要求,通过电路改进以避免使用片外元件,实现了单片集成.根据神经信号的特点,电路频率响应带宽设计为59Hz～12.8kHz,增益80dB.采用时域方法测试,芯片达到设计目标,有望用于体内神经信号检测.依据测试结果分析了电路特性并提出改进方法.     

A multi-channel analog IC for in vitro neural recording

Recent work in the field of neurophysiology has demonstrated that, by observing the firing characteristic of action potentials (AP) and the exchange pattern of signals between neurons, it is possible to reveal the nature of "memory" and "thinking" and help humans to understand how the brain works. To address these needs, we developed a prototype fully integrated circuit (IC) with micro-electrode array (MEA) for neural recording. In this scheme, the microelectrode array is composed by 64 detection electrodes and 2 reference electrodes. The proposed IC consists of 8 recording channels with an area of 5 × 5 mm². Each channel can operate independently to process the neural signal by amplifying, filtering, etc. The chip is fabricated in 0.5-μ m CMOS technology. The simulated and measured results show the system provides an effective device for recording feeble signal such as neural signals.     

成纤维细胞和血小板在多壁碳纳米管上粘附性

使用化学气相沉积(CVD)的方法在碳纸基底上制备了多壁碳纳米管(MWCNTs),并研究了L929小鼠成纤维细胞在多壁碳纳米管和碳纸对照组上的粘附及增殖等生长行为,以及各种血液蛋白吸附于这两种材料表面后对人皮肤成纤维细胞粘附产生的影响,同时对比了这两种材料的血小板粘附情况.结果表明:种植在多壁碳纳米管上的成纤维细胞生长明显比碳纸上的旺盛,细胞浓度从第1天的12.5×10~5/mL明显增加到第7天的4.1×10~5/mL,多壁碳纳米管对细胞无毒性反应.预吸附白蛋白、纤维蛋白原、免疫球蛋白对细胞粘附量有促进作用,并且多壁碳纳米管的血小板粘附率低于碳纸.这些结果证明多壁碳纳米管具有良好的组织相容性和一定的血液相容性.