An electrochemiluminescent magneto-immunosensor for ultrasensitive detection of hs-cTnI on a microfluidic chip

Sensitive detection and precise quantitation of trace-level crucial biomarkers in a complex sample matrix has become an important area of research.For example,the detection of high-sensitivity cardiac troponin I (hs-cTnI) is strongly recommended in clinical guidelines for early diagnosis of acute myocardial infarction.Based on the use of an electrode modified by single-walled carbon nanotubes (SWCNTs) and a Ru(bpy)32+-doped silica nanoparticle (Ru@SiO2)/tripropylamine (TPA) system,a novel type of electrochemiluminescent (ECL) magnetoimmunosensor is developed for ultrasensitive detection of hs-cTnI.In this approach,a large amount of[Ru(bpy)3]2+is loaded in SiO2(silica nanoparticles) as luminophores with high luminescent efficiency and SWCNTs as electrode surface modification material with excellent electrooxidation ability for TPA.Subsequently,a hierarchical micropillar array of microstructures is fabricated with a magnet placed at each end to efficiently confine a single layer of immunomagnetic microbeads on the surface of the electrode and enable 7.5-fold signal enhancement In particular,the use of transparent SWCNTs to modify a transparent ITO electrode provides a two-order-of-magnitude ECL signal amplification.A good linear calibration curve is developed for hs-cTnI concentrations over a wide range from 10 fg/ml to 10 ng/ml,with the limit of detection calculated as 8.720 fg/ml (S/N=3).This ultrasensitive immunosensor exhibits superior detection performance with remarkable stability,reproducibility,and selectivity.Satisfactory recoveries are obtained in the detection of hs-cTnI in human serum,providing a potentia analysis protocol for clinical applications.

Highly Sensitive Chemiluminescence Detection for PDMS/GIass Micro-chip Electrophoresis

This paper described a highly sensitive chemiluminescence detection system for micro-chip electrophoresis (MCE) based on luminol-hydrogen peroxide reaction catalyzed by the metal ions. The micro-chip was composed of poly(dimethylsiloxane) (PDMS) and glass, and was fabricated by micro-machining technology. The surface of channels was dynamically modified by polydimethylacrylamide (PDMA) in order to eliminate unhomogeneous electroosmotic flow (EOF) of the PDMS/glass chip, adsorption of molecules, and improve hydrophobicity on PDMS surface. The detection modes, reagent mix procedures and reaction conditions were optimized and the detection limit of 5×10 mol/L for cobalt (II) was achieved by MCE with chemiluminescence detection, which was about four orders of magnitude more sensitive than that reported in the reference.

Advances in microfluidic-based DNA methylation analysis

DNA methylation has been extensively investigated in recent years,not least because of its known relationship with various diseases.Progress in analytical methods can greatly increase the relevance of DNA methylation studies to both clinical medicine and scientific research.Microflu-idic chips are excellent carriers for molecular analysis,and their use can provide improvements from multiple aspects.On-chip molecular analysis has received extensive attention owing to its advantages of portability,high throughput,low cost,and high efficiency.In recent years,the use of novel microfluidic chips for DNA methylation analysis has been widely reported and has shown obvious superiority to conventional methods.In this review,wefirst focus on DNA methylation and its applications.Then,we discuss advanced microfluidic-based methods for DNA methylation analysis and describe the great progress that has been made in recent years.Finally,we summarize the advantages that microfluidic technology brings to DNA methylation analysis and describe several challenges and perspectives for on-chip DNA methylation analysis.This review should help researchers improve their understanding and make progress in developing microfluidic-based methods for DNA methylation analysis.

Micro-LED芯片激光去除机理及工艺参数优化

为提高面板级Micro-LED显示面板的制造质量,需要对不良Micro-LED芯片进行原位去除与修复,利用COMSOL建立激光双温烧蚀模型,开展了Micro-LED不良芯片激光去除机理和工艺参数的优化。通过单脉冲激光对MicroLED芯片烧蚀所形成表面光斑的直径平方来推算Micro-LED的烧蚀阈值,拟合出激光参数与烧蚀深度的关系,并对双温烧蚀模型的准确性进行验证;分析了激光光斑重叠率、能量密度和不同扫描路径下对应芯片的烧蚀特征及去除机理,结合双温烧蚀模型完成了激光扫描路径及对应工艺参数的优化。结果表明,飞秒激光烧蚀模型对Micro-LED芯片激光烧蚀加工的最大分析误差为9.28%,优化的激光去除模式实现了1秒/颗的快速精准剥离和焊盘表面的高质量整平修复,对大幅面Micro-LED显示面板规模化生产中不良芯片的快速修复具有重要的指导作用。

Combination of Micro-fluidic Chip with Fluorescence Correlation Spectroscopy for Single Molecule Detection

A single molecule detection technique was developed by the combination of a single channel poly （dimethylsiloxane）/glass micro-fluidic chip and fluorescence correlation spectroscopy （FCS）. This method was successfully used to determine the proportion of two model components in the mixture containing fluorescein and the rhodamine-green succinimidyl ester.

Stable ^(85)Rb micro vapour cells:fabrication based on anodic bonding and application in chip-scale atomic clocks

We describe the microfabrication of ^85Rb vapour cells using a glass-silicon anodic bonding technique and in situ chemical reaction between rubidium chloride and barium azide to produce Rb. Under controlled conditions, the pure metallic Rb drops and buffer gases were obtained in the cells with a few mm^3 internal volumes during the cell sealing process. At an ambient temperature of 90 ℃ the optical absorption resonance of ^85Rb D1 transition with proper broadening and the corresponding coherent population trapping （CPT） resonance, with a signal contrast of 1.5% and linewidth of about 1.7 kHz, have been detected. The sealing quality and the stability of the cells have also been demonstrated experimentally by using the helium leaking detection and the after-9-month optoelectronics measurement which shows a similar CPT signal as its original status. In addition, the physics package of chip-scale atomic clock （CSAC） based on the cell was realized. The measured frequency stability of the physics package can reach to 2.1 × 10^-10 at one second when the cell was heated to 100 ℃ which proved that the cell has the quality to be used in portable and battery-operated devices.

Micro RNA在原发性腹膜后脂肪肉瘤组织中表达差异谱的研究

目的:建立原发性腹膜后脂肪肉瘤组织与正常脂肪组织micro RNA(miRNA)表达的差异谱,为研究miRNA在原发性腹膜后脂肪肉瘤发生中的作用提供新的线索。方法:收集4例原发性腹膜后脂肪肉瘤患者根治性手术后肿瘤组织及正常对照脂肪组织,利用miRNA芯片技术,将瘤组织miRNA与人的脂肪组织miRNA表达谱芯片进行标记杂交实验后进行数据信号提取并进行差异表达分析。结果:原发性腹膜后脂肪肉瘤组织与正常脂肪组织中所表达miRNA中有38个存在明显差异(P<0.05),包含23个高表达miRNA和15个低表达miRNA,其中10个差异显著(P<0.01),包含4个高表达miRNA和6个低表达miRNA。结论:原发性腹膜后脂肪肉瘤组织较正常脂肪组织miRNA高表达数多于低表达数,提示可能在肿瘤组织中基因表达量较正常组织低;部分miRNA可能参与腹膜后脂肪肉瘤恶变的分子机制,这部分miRNA及其下游靶基因可以作为靶向治疗的靶点,部分高表达的miRNA可以作为新型肿瘤标志物。

高亮度Micro-LED外延和芯片制备

微米LED(Micro-LED)是指尺寸在50μm以下,去除外延衬底的LED,相比目前的LCD,OLED显示具有高亮度、高分辨率,低能耗等优势。本文首先介绍了Micro-LED外延和芯片制备中存在的主要问题。接着使用ABC模型以及载流子泄露模型分析了小电流密度下的Micro-LED外量子效率低的原因,给出了目前国际上解决这一问题的主要技术途径。在Micro-LED外延技术上重点介绍了NPSS外延Micro-LED的优势以及目前NPSS的制备、外延GaN的进展情况。在芯片制备上,则介绍了Micro-LED微纳出光结构,多芯片的高色域混光技术,AlInGaP红光,氮化物红光以及量子点激发的红光路线。最后讨论了Micro-LED外延和芯片当前的现状和未来的发展趋势。

缺氧微环境下人肺腺癌A549细胞的microRNA基因芯片结果分析

目的研究缺氧对肺腺癌A549细胞中micro RNA(mi RNA)表达谱的影响,分析靶基因参与的生物学功能和通路。方法基于mi RNA芯片技术和生物信息学分析方法,分析缺氧条件和正常氧条件下培养的A549细胞中差异表达的mi RNA,并预测该mi RNA的靶基因,分析靶基因参与的生物学功能和通路。结果本研究共筛选出14个差异表达mi RNA,包括9个在缺氧细胞中上调mi RNA和5个下调mi RNA。上调和下调mi RNA的靶基因都参与DNA转录、核染色质修饰等功能,并且都参与Wnt信号、转化生长因子-β信号和丝裂原活化蛋白激酶信号通路。结论缺氧的肺腺癌A549细胞中mi RNA表达谱发生显著改变,一些差异表达mi RNA对某些基因具有调控作用。

蓝光GaN基Micro-LED芯片制备及激光剥离工艺研究

基于半导体制造工艺,制备了尺寸为50μm×80μm的蓝光氮化镓(GaN)基MicroLED芯片。芯片的正向导通电压在2.55V左右;测试了10颗LED芯片在1mA注入电流下的电压值,得到的最大值和最小值分别为3.24和3.12V,波动幅度在4%以内。在1mA的测试电流下,测试芯片的EL光谱峰值波长和半高宽分别为453和14.4nm,芯片的外量子效率可达12.38%,芯片发光均匀且亮度很大。测试结果表明,所制备的Micro-LED芯片具有优异的光电性能。此外,通过激光剥离技术,实现了Micro-LED芯片的转移。研究了激光剥离工艺对MicroLED芯片光电性能的影响,发现在优化的工艺条件下,激光剥离对芯片的光电性能几乎无影响。这些结果有助于小间距微尺寸LED芯片阵列及显示技术的研究。

Micro LED微显示芯片制备技术

Micro LED微显示技术是将传统LED薄膜化、微小化和矩阵化,像素点距离从毫米级降至微米级,并在一个芯片上高度集成的固体自发光显示技术,因其低功耗、响应快、寿命长、发光效率高等特点,被视为一种独特的显示面板技术。本文主要介绍了Micro LED微显示芯片的制备技术,包括芯片结构设计、制备技术优化、光电集成芯片制备技术、巨量转移技术,最后介绍了芯片小型化效应。

高分辨率主动驱动型氮化镓基Micro-LED芯片的制备

本文设计并制备了一款分辨率为1920×1080的氮化镓基Micro-LED芯片。采用单次ICP(InductivelyCoupled Plasma)刻蚀的方法完成电流扩展层的图案化和台面刻蚀,实现了电流扩展层和台面的自对准。同时,在制作过程中用HMDS(Hexamethyldisiloxane)提高光刻胶附着力,从根本上提高小尺寸台面刻蚀的一致性和完整性。此外,通过垫高N型电极解决了传统倒装芯片中P型电极和N型电极不等高的问题,有利于显示芯片与驱动芯片的键合。该芯片尺寸为17.78 mm(0.7 in),发光单元尺寸为6μm,像素周期为8μm,像素密度达到3129 PPI。I-V测试数据表明,所制备的Micro-LED的开启电压仅为3.5 V。

PDMS微流控芯片微筛阵列流场的Micro-PIV分析

针对微流控芯片上的细胞培养技术,很多微流控芯片设计力图追求高通量,但并未考虑芯片中流场的分布状态,导致细胞培养效果不佳.本文介绍了直径1μm的荧光粒子以30μL/min的速度注入芯片中,利用Micro-PIV技术对设计的含有16μm微筛阵列的PDMS微流控芯片进行流场、流速的测试与分析,得到高分辨率的流场、速度矢量分布图,并且与ANSYS软件模拟结果进行比较.实验结果表明:液体经过微筛阵列时,流速逐渐减小,流场分布稳定均一,模拟结果与实际结果吻合.

芯片级原子钟在Micro-PNT中的应用

将CPT芯片原子钟与高精度的微惯性测量元件组合成单片授时和惯性测量单元(TIMU),再与高精度的GNSS系统相结合,可以弥补GNSS和INS单一系统的不足,组合成适用性更广、鲁棒性更强的微型PNT系统(micro-PNT)。

Single layer atom chip for magnetically trapping one-dimensional array of ultracold atoms

We propose a wire configuration to create a one-dimensional （1D） array of magnetic microtraps for trapping ultracold atoms. The configuration is formed by replacing the central part of the Z-wire pattern with a zigzag wire. We simulate the performance of this pattern by the finite element method which can take both the width and depth of the wire into consideration. The result of simulation shows that this configuration can create magnetic microtraps which can be separated and combined by changing bias magnetic field. We manage to split Z-wire trap and prove that similar result can occur for the new wire configuration. The fabrication processes of the atom chip are also introduced. Finally we discuss the loading method.

Characteristics and Formation Mechanism for Stainless Steel Fiber with Periodic Micro-fins

Metal fibers have been widely used in many industrial applications due to their unique advantages. In certain applications, such as catalyst supports or orthopedic implants, a rough surface or tiny outshoots on the surface of metal fibers to increase surface area are needed. However, it has not been concerned about the surface morphologies of metal fiber in the current research of metal fiber manufacturing. In this paper, a special multi-tooth tool composed of a row of triangular tiny teeth is designed. The entire cutting layer of multi-tooth tool bifurcates into several thin cutting layers due to tiny teeth involved in cutting. As a result, several stainless steel fibers with periodic micro-fins are produced simultaneously. Morphology of periodic micro-fins is found to be diverse and can be classified into three categories： unilateral plane, unilateral tapering and bilateral. There are two forming mechanisms for the micro-fins. One is that periodic burrs remained on the free side of cutting layer of a tiny tooth create micro-fins of stainless steel fiber produced by the next neighboring tiny tooth; the other is that the connections between two fibers stuck together come to be micro-fins if the two fibers are finally detached. Influence of cutting conditions on formation of micro-fins is investigated. Experimental results show that cutting depth has no significant effect on micro-fin formation, high cutting speed is conducive to micro-fin formation, and feed should be between 0.12 mm/r and 0.2 mm/r to reliably obtain stainless steel fiber with micro-fins. This research presents a new pattern of stainless steel fiber characterized by periodic micro-fins formed on the edge of fiber and its manufacturing method.

基于200 mm硅基GaN的单色Micro LED微显示芯片制备及量产难点分析

应用200 mm硅基GaN外延片,研究晶圆级键合、薄膜转移和微小尺寸像素制备等技术,实现了Micro LED微显示阵列的点亮与显示功能。相对于传统蓝宝石基GaN外延晶圆,200 mm硅基GaN外延晶圆与硅基驱动晶圆尺寸更匹配,有利于通过晶圆键合工艺实现低成本量产。同时对工艺量产的难点和解决思路进行了分析,指出显示缺陷是目前亟待解决的问题。

贺信精神引领下微纳加工技术课课程思政教学改革与实践

微纳加工技术课程的教学内容与我国当前所面临的高端芯片制造“卡脖子”技术密切相连。2020年以来该课程将习近平总书记贺信精神融入课程思政教学设计,通过寓德于教、寓哲于教、寓念于教和寓新于教的“四位一体”方式,引导学生树立坚定理想信念,厚植爱国主义情怀,提升品德修养,激发远大志向。该文列举多个典型案例,经过教学改革基本实现知识传授、价值引领和情怀根植三方面的有机统一,期待该教学设计及经验分享为全国各高校电子封装专业的课程思政教学改革提供借鉴。

叠氮化银起爆药连续化合成芯片的设计与应用研究

针对叠氮化银(AgN3,简写为SA)起爆药合成过程对于反应溶液快速混合的要求,设计制作了连续反向旋T形微混合芯片,并采用Ansys Fluent仿真模拟软件对芯片结构及反应物流速等因素对混合效率的影响规律进行了研究,优化获得了高效微混合芯片结构。使用该芯片进行了纳米SA起爆药的连续化合成,通过扫描电子显微镜(SEM)、X射线衍射(XRD)、傅里叶变换红外光谱(FTIR)、差示扫描量热(DSC)研究了SA起爆药的形貌、成分结构与热性能。结果表明:当微混合芯片的通道尺寸为1 mm,对撞角度180°,反应物流速4 mL·min^(-1)以上时,可获得接近100%的混合效率。通过调节反应物流速、浓度和添加表面活性剂,可有效调控产物粒径及其分布,且反应产物主要成分为正交晶系的AgN3晶体。相较常规方法,使用微流控方法制备的SA起爆药放热峰温度由365.2℃提前到358.2℃(降低7℃),且放热量由851.6 kJ·kg^(-1)升高到976.7 kJ·kg^(-1)(升高14.7%),表明微流控方法制备的SA起爆药具有更高的反应活性和能量。