共查询到19条相似文献,搜索用时 62 毫秒
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针对限制液晶微滴生物传感响应性能的微滴尺寸不均一的问题,设计了流动聚焦微流控芯片结构,系统研究了单分散液晶微滴光学探针的制备方法及传感响应特性。以向列型液晶为分散相,十二烷基硫酸钠/聚乙烯醇混合液为连续相,通过控制流动聚焦时两相流速来调节影响液晶微滴生成的不同流动模式。测试并分析了两相流速、连续相粘度、孔口宽度等参数对液晶微滴尺寸的影响及其内在机制。利用不同尺寸的液晶微滴为传感探针,检测并分析了肝肠疾病的潜在标志物脱氧胆酸。结果表明,当液晶微滴尺寸从38μm增加到77μm时,脱氧胆酸的检出限从(383䥺SymbolqB@23.6)μmol/L降低到(140䥺SymbolqB@14.1)μmol/L。 相似文献
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以简单、快速的微流控酶促反应方法实现了尿素浓度的可视化检测。 在微流控双水相液滴流动中,利用脲酶水解尿素生成碳酸铵使液滴内的中性红指示剂变色,并对液滴颜色强度进行分析来确定待测样品中尿素的浓度,检测范围可达到0~50 mg/mL。 双水相体系克服了传统油水分析检测平台生物相容性低的缺陷。 液滴流以较少的试剂消耗、极大的比表面积、微米级的扩散距离大大提高了反应速率,导致了较快的分析检测速度,将检测时间缩短为20 s左右。 为应用化学领域的尿素快速分析检测提供借鉴和参考。 相似文献
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组装了由注射泵进样系统、微流控芯片和三温区加热器组成的流动型PCR扩增系统,该系统具有扩增速度快、交叉污染小、芯片可重复使用和操作方便等特点.优化了芯片厚度、隔热材料和流速等影响PCR扩增的因素.在4.9min内经24个循环成功地扩增了浓度为1ng/100μL的λ-DNA(500bp). 相似文献
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为了开发新的纸芯片制备技术制作高精度的纸基微流控芯片,该文提出了一种基于无掩膜光刻技术的新制备方法。以疏水图案的表面接触角和液体在微流控通道内的流动情况为评价标准,研究了曝光、显影等关键工艺对疏水区域疏水强度以及液体流动情况的影响。研究结果表明,仅需2 s曝光时间制备的纸芯片疏水区域的接触角可达100.56°,亲疏水区域具有明显的区分,最小可实现的亲水通道和疏水屏障分别为(68±5)μm和(104±9)μm。将纸基芯片用于亚硝酸盐的检测,溶液浓度与显色区颜色强度之间呈良好的相关性,线性方程为Y=3.450X+34.83,r2=0.977 0。无掩模光刻法制备纸芯片无需制作掩膜版,减少了芯片制作的成本和时间,工艺简便,芯片精度高,为纸芯片制备和应用提供了有效手段。 相似文献
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硝酸盐、亚硝酸盐和氨氮(简称"三氮")是水体中的主要污染物,目前我国的地表水和浅层地下水中普遍存在三氮污染问题。本研究将显色法与纸基微流控技术结合,制备了单通道纸基微流控芯片,在优化的反应条件下,分别对3种含氮化合物进行检测,亚硝酸盐、硝酸盐和氨氮的检出限分别为0.001 mmol/L、 1 mmol/L和1 mg/L;在实际样本的检测中,3种样本的加标回收率均在95.4%~114.9%之内。其次,通过合理的结构设计将分别用于3种含氮化合物检测的单通道纸基微流控芯片集成于一体,制备出用于三氮同时检测的多通道纸基微流控芯片,多通道纸基微流控芯片的检测结果与单通道纸基微流控芯片的检测结果具有良好的一致性。本研究提出的基于显色法的多通道纸基微流控芯片可对水中的三氮进行同时检测,并且,此芯片具有成本低廉、灵敏度高和便于操作等特点,适用于现场快速检测,有望在资源匮乏的水源污染地区推广。 相似文献
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微流控液滴技术:微液滴生成与操控 总被引:1,自引:0,他引:1
微液滴技术因具有高通量两相分割分离能力,吸引众多不同领域研究者的关注.本文回顾了微流控液滴技术领域的一些基本技术思路,涉及微液滴的流控生成方法,包括水动力法、电动法、气动法、光控法等,以及液滴生成后的操控技术,如液滴定向位移、融合、裂分、混合、分选、捕获等,同时对这些方法作了简要评述. 相似文献
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Nicheng Chen Jizhou Wu Hanmei Jiang 《Journal of Dispersion Science and Technology》2013,34(11):1635-1641
Droplet formation in a wide-type microfluidic T-junction was studied using the computational fluid dynamics (CFD) method. Two distinct regimes of droplet formation were confirmed: dripping and jetting; and, at both regimes, droplet size decreases with an increase in capillary number. CFD simulation demonstrated that droplet formation in the T-junction can be divided into three steps: droplet emergence and growing up; separation with the disperse phase; and detachment from the channel wall. The wettability of the channel wall significantly affects the process of droplet detachment from the channel wall; also, the simulation clearly showed that droplets can be formed only when the continuous phase fluid preferentially wets the channel wall, that is, its contact angle on the wall is smaller than 90°. Finally, the CFD study verified that the disperse phase flow rate can significantly affect the droplet size as well as the mechanism of droplet formation. 相似文献
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微流控芯片以其强大的微流体和微小物质控制能力成为研究单细胞、细胞群落乃至生物组织的重要手段。在本篇综述中,我们将以微流控芯片上细胞体外培养模型的建立为主,对近几年来重要的研究工作加以评述,全面地介绍微流控技术在细胞生命科学研究中应用的优势和未来发展方向,具体包括微流控芯片的细胞操控能力、细胞培养微环境的构建以及芯片联用检测手段,希望为从事这一领域研究工作的读者提供一些新的思路。 相似文献
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Teo Lombardo Lidia Lancellotti Christelle Souprayen Catherine Sella Laurent Thouin 《Electroanalysis》2019,31(11):2103-2111
Microfluidic devices were designed to electrochemically detect in a two‐phase flow the velocity, size and content of aqueous droplets containing redox species. The principle of these determinations is based on the analysis of a unique chronoamperometric response recorded during the passage of a droplet over channel microelectrodes. Two configurations of electrochemical cell with different geometries were investigated both theoretically and experimentally. Velocity and size of droplets, as well as internal recirculating convection within droplets, were evaluated from chronoamperometric curves by specific transition times depending on the cell configuration. In addition, the droplet content was probed from the Faradaic current controlled by mass transport and by internal hydrodynamic regime. For droplet velocity and size, experimental data were systematically compared to optical measurements. All the results demonstrated the high performance of the electrochemical detection reached under these conditions. They successfully validate the concept of self‐consistent electrochemical detections of aqueous droplets within microchannels for the simultaneous determination of their velocity, size and content. 相似文献
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Keine Nishiyama Koki Hoshikawa Masatoshi Maeki Akihiko Ishida Hirofumi Tani Manabu Tokeshi 《Electroanalysis》2019,31(9):1736-1743
A concentric ring array electrode that amplifies the current signal without redox cycling has been developed for highly sensitive electrochemical detection at a single potential in a microfluidic platform. Herein, the effect of ring‐electrode width on the current and current density was examined. A ring‐array electrode with widths that decrease from the inner to the outer ring was shown to exhibit the highest sensitivity. This electrode delivered a current density that was approximately 50 % higher than that of a conventionally used disc electrode. We used numerical simulations to further optimize this type of array electrode, which led to a limit of detection for catechol of 6.2 nmol/L. This ring array electrode has great potential for use in a variety of applications because it can be used to detect irreversible targets with a simple apparatus at a single potential and requires no electrode modification to achieve high sensitivity. 相似文献