首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 125 毫秒
1.
崔嘉轩  刘璐  李东浩  朴相范 《色谱》2021,39(11):1157-1170
微纳尺度物质的分离和分选在精准医学、材料科学和单细胞分析等研究中至关重要。精准、高效和快速的分离微纳尺度物质能够为癌症的早期诊断、生物样品检测和细胞筛选提供重要帮助,其中基于外加场分离技术的分离微纳尺度物质因可以对微纳尺度物质高效在线分离和分选,被广泛应用于微纳米颗粒、外泌体以及生物细胞的分离工作中,而目前多数外加场分离技术存在装备繁琐和样品消耗大等问题。微流控技术是一种通过制作微通道和微流控芯片操纵微小流体对微纳尺度样品组分进行分离的技术,因具有快速检测、高通量、在线分离、集成性高、成本低等优势现被应用于微纳尺度物质分离分析中,是一种微纳尺度物质分离的有效方法,通过在微流控芯片上设计不同的通道及外部配件提高主动场对微纳尺度物质分离效率。外加场分离技术与微流控技术联用可以实现微纳尺度物质的无损、高效、在线分离。该综述主要概述了近年来在微流控芯片上依托流动场、电场、磁场及声场等外加场分离技术来提高对微纳尺度物质分离效率的研究现状,并将各个外力场对单细胞、微颗粒等微纳尺度物质的分离进行分类介绍,总结各自的优缺点及发展应用,最后展望了外加场分离技术与微流控技术联用在应用于癌细胞的早期筛查、精确分离微尺度物质领域的未来发展前景,并提出联用技术的优势和未来应用等。  相似文献   

2.
以棉涤线作为分离载体,采用自制的微流控通道装置,研究并建立了一种新型棉涤线微流控通道分离方法。探讨了进样方式、微流控通道长度、微流控通道倾斜度以及展开剂对混合染料分离的影响。在优化条件下,方法应用于孔雀石绿和罗丹明B混合染料的分离,各组分色段清晰。表明棉涤线作为新的分离载体对混合物进行分离,操作简便,对分离环境要求低,具有一定的应用价值。  相似文献   

3.
微流控芯片中颗粒/细胞的磁操控是当前的热点研究领域.本文详细介绍了微流控芯片中颗粒/细胞磁操控原理及几种主要操控方式,包括分离、集中、捕获与排列组装.其中,基于颗粒/细胞大小、形状以及有无磁性对分离方法展开详述.此外,本文还比较了通道几何结构、磁场强度及分布、磁性液体种类(顺磁盐溶液和磁流体)对操控性能的影响.最后,针对微流控芯片中颗粒/细胞磁操控的前景进行了展望.  相似文献   

4.
基于微流控二维电泳芯片(2D-EMC)的流路特点,建立等效电阻模型,以便给出各端电压的合理取值范围,成功实现微流控芯片二维电泳分离.经实验测定各微通道电阻,在各端电压合理取值范围内,通过电流测量调整(优化)电压,得到了一组优化的电压控制方案,在化学发光-2D-EMC系统中成功实现了精氨酸和甘氨酸衍生物的二维分离.本方法显著减小了实现微流控芯片二维电泳分离的实验次数.  相似文献   

5.
表面增强拉曼光谱(SERS)因极高的检测灵敏度且能够提供丰富的分子结构信息,可实现原位、实时监测等优点而成为广受关注的痕量分析工具.本文发展了基于微流控和SERS的联用技术,实现了微有机合成反应的现场监测.以磁性核壳纳米粒子Fe3O4@Ag为SERS基底,通过外加磁场调控富集实现连续的SERS检测;结合微流控反应器在有机合成中反应物用量少、效率高、易于实现在线检测和高通量筛选的优势,实现了α-苯乙醇的微量合成反应以及实时SERS监测.研究表明,Fe3O4@Ag核壳纳米粒子具备在微流控反应通道中的磁富集功能和SERS连续检测的性能.通过改变微流控通道中反应物的流速可调控反应速度,在固定时间内获得不同浓度的反应物,利用差谱技术消除反应物光谱的干扰,获得了产物α-苯乙醇的特征SERS光谱.结果表明微流控技术与SERS联用可发展成为微量有机反应的监测手段,在有机化学反应高通量筛选中具有潜在应用价值.  相似文献   

6.
本发明涉及微流控芯片系统的进样方法。在使用固定相的微流控芯片系统中,于芯片分离通道与流动相人口之间设置两个或两个以上的分流通道。通过控制其中流体的切换和截止,实现对微流控芯片系统的大体积进样。该方法适合于微流控芯片中电色谱、加压电色谱和液相色谱模式下的大体积进样。该方法的优点为:可实现微流控芯片中大体积样品的上样;克服了系统中的梯度延迟效应,  相似文献   

7.
微流控芯片上的细胞分析研究进展   总被引:2,自引:0,他引:2  
近年来,微流控分析系统(μTAS)在生物细胞分离领域的发展引起了广泛的关注。微流控芯片的微米级尺寸的通道适合于单细胞样品的引入、操控、反应、分离和检测,已经在微芯片上实现了上述功能,并将这些功能集成在具备毛细管电泳分离功能的微芯片上。  相似文献   

8.
采用三层夹心式、三平行微电极设计制作了聚二甲基硅氧烷(Polydimethylsiloxane,PDMS)/玻璃微流控芯片,通过交流电对在微流控芯片中的高电导率溶液施加电场,达到不同尺寸聚苯乙烯(Polystyrene,PS)微球分离的目的;探讨了微球定向运动的动电学原理。结果表明,在电压为14 V,频率为100 k Hz时,直径为10和25μm的PS微球分离效率最好;在电压为10 V,频率为2 MHz时,直径为5和25μm的PS微球分离效率最好;对于直径分别为5、10和25μm的3种PS微球分离,在电压为11 V,频率为1 MHz时,可以达到大球和另外两种尺寸较小微球的快速有效分离,分离效率均可达90%以上。结果表明,相邻电极中间位置层流区域的形成,对微球分离起到关键作用。  相似文献   

9.
微流控芯片技术在生命科学研究中的应用   总被引:4,自引:0,他引:4  
微流控芯片最初起源于分析化学领域,是一种采用精细加工技术,在数平方厘米的基片,制作出微通道网络结构及其它功能单元,以实现集微量样品制备、进样、反应、分离及检测于一体的快速、高效、低耗的微型分析实验装置.随着微电子及微机械制作技术的不断进步,近年来微流控芯片技术发展迅猛,并开始在化学、生命科学及医学器件等领域发挥重要作用.本文首先简单介绍了微流控芯片制作材料和工艺,然后主要阐述了其在蛋白质分离、免疫分析、DNA分析和测序、细胞培养及检测等方面的应用进展.  相似文献   

10.
采用化学沉积法将金沉积到聚碳酸酯膜内孔壁,制备了呈负电性的阵列金纳米通道.在外加恒电压作用下,阳离子型的百草枯选择性通过负电性的金纳米通道,阿特拉津为分子型化合物,不受电荷选择性和电泳作用影响,难以在金纳米通道内迁移.借此,可实现二者的分离.  相似文献   

11.
电容去离子技术(Capacitive Deionization,CDI)可以通过断电或电极反接方式使盐离子脱附,达到电极再生的目的,实现电极的可循环利用,其在海水淡化处理技术中具有独特的优势,逐渐成为一种缓和淡水资源紧缺和水污染的极具前景的技术手段。近年来,CDI处理技术正在向电极高效、无二次污染方向转变,未来将进一步聚焦碳基电极材料功能化(碳材料,钛碳化物MXenes,掺杂改性石墨烯材料)、装置和工艺设计优化等重要方向。为深入研究CDI海水淡化技术机理,进一步探索CDI方法在实际应用中的潜力,分别对CDI的脱盐机理、电极材料、装置和工艺设计对电吸附效率和性能的研究进展进行了总结,回顾CDI脱盐效果与电极材料、CDI电池装置设计等因素之间的密切关系,并对CDI技术在海水淡化中的研究发展提出展望。  相似文献   

12.
Molecular dynamics simulation was used to study the effect of the outer-wall on water flux in the inner channel by varying the inter-layer spacing of unconventional double-walled carbon nanotube (DWCNT) under reverse-osmosis conditions. Salt rejection and the water transport behavior inside the DWCNT were also examined. In the simulation, 0.5 mol·L-1 NaCl aqueous solution was used to mimic seawater, and the chiral index of the inner-wall was fixed at (8, 8). A constant force on the salt solution produced pressure. Calculation of the number density profile of ions along the DWCNT axis showed that the water could be separated completely from the NaCl aqueous solution in some types of DWCNTs studied. Analyses of the hydrogen-bond lifetime, potential of mean force, and dipole moment distribution of the water molecules inside the DWCNT showed different permeabilities by water molecules and ions. An increase in the inter-layer spacing improved water flow in the DWCNT, which decreased the salt rejection performance. Finally, it was found that DWCNT with an inter-layer spacing of 0.815 nm gave the optimum balance between water flux and salt rejection. This study provides a molecular insight into the use of DWCNT in desalination, and will enable the design of improved reverse-osmosis membranes with high performance in terms of salt rejection and water permeability.  相似文献   

13.
Autonomous micro/nano mechanical, chemical, and biomedical sensors require persistent power sources scaled to their size. Realization of autonomous micro‐power sources is a challenging task, as it requires combination of wireless energy supply, conversion, storage, and delivery to the sensor. Herein, we realized a solar‐light‐driven power source that consists of a micro fuel cell (μFC) and a photocatalytic micro fuel generator (μFG) integrated on a single microfluidic chip. The μFG produces hydrogen by photocatalytic water splitting under solar light. The hydrogen fuel is then consumed by the μFC to generate electricity. Importantly, the by‐product water returns back to the photocatalytic μFG via recirculation loop without losses. Both devices rely on novel phenomena in extended‐nano‐fluidic channels that ensure ultra‐fast proton transport. As a proof of concept, we demonstrate that μFG/μFC source achieves remarkable energy density of ca. 17.2 mWh cm−2 at room temperature.  相似文献   

14.
《中国化学快报》2021,32(10):3090-3094
The Co@NCNTs/Si pillars with channels is assemble to a suitable pure water gathering device, which is applied in seawater desalination and sewage purification to produce pure water by utilizing solar energy. High-efficiency utilization of solar energy to generate water vapor is popular, recyclable, and environmentally friendly for seawater desalination and sewage purification, helping to alleviate the global water shortage crisis. Here, we report an efficient and simple method to prepare a three-dimensional (3D) evaporator for steam generation by harnessing the power of the sun. This evaporation is composed of one-dimensional (1D) cobalt embedded and nitrogen doped carbon nanotubes (Co@NCNTs) and 3D silicon pillars array structure (Si pillars). The Co@NCNTs/Si pillars shows a wide light absorption range provided by carbon nanotubes and a long light absorption path because of the silicon pillars. The surface temperature of the sample rises rapidly in 1.5 min and exceed 80 °C under solar illumination of one sun. The water evaporation can be high as 1.21 kg m−2 h−1 under one sun irradiation (1 kW/m2) with the energy efficiency up to 82.4%. This scalable Co@NCNTs/Si pillars can prepare pure water from seawater and sewage, where the removal rate of ions in seawater and pollutants in sewage is similar to 100%. Based on our research, this multistage three-dimensional structure is a simple and efficient novel photothermal material for extensive seawater desalination and sewage purification.  相似文献   

15.
Biofouling on reverse osmosis (RO) membranes is the most serious problem which affects desalination process efficiency and increases operation cost. The biofouling cannot be effectively removed by the conventional pre-treatment traditionally used in desalination plants. Hybrid membrane systems coupling the adsorption and/or coagulation with low-pressure membranes can be a sustainable pre-treatment in reducing membrane fouling and at the same time improving the feed water quality to the seawater reverse osmosis. The addition of powder activated carbon (PAC) of 1.5 g/L into submerged membrane system could help to remove significant amount of both hydrophobic compounds (81.4%) and hydrophilic compounds (73.3%). When this submerged membrane adsorption hybrid system (SMAHS) was combined with FeCl(3) coagulation of 0.5 mg of Fe(3+)/L, dissolved organic carbon removal efficiency was excellent even with lower dose of PAC (0.5 g/L). Detailed microbial studies conducted with the SMAHS and the submerged membrane coagulation-adsorption hybrid system (SMCAHS) showed that these hybrid systems can significantly remove the total bacteria which contain also live cells. As a result, microbial adenosine triphosphate (ATP) as well as total ATP concentrations in treated seawater and foulants was considerably decreased. The bacteria number in feed water prior to RO reduced from 5.10E(+06) cells/mL to 3.10E(+03) cells/mL and 9.30E(+03) cells/mL after SMAHS and SMCAHS were applied as pre-treatment, respectively. These led to a significant reduction of assimilable organic carbon (AOC) by 10.1 μg/L acetate-C when SMCAHS was used as a pre-treatment after 45-h RO operation. In this study, AOC method was modified to measure the growth of bacteria in seawater by using the Pseudomonas P.60 strain.  相似文献   

16.
Autonomous micro/nano mechanical, chemical, and biomedical sensors require persistent power sources scaled to their size. Realization of autonomous micro-power sources is a challenging task, as it requires combination of wireless energy supply, conversion, storage, and delivery to the sensor. Herein, we realized a solar-light-driven power source that consists of a micro fuel cell (μFC) and a photocatalytic micro fuel generator (μFG) integrated on a single microfluidic chip. The μFG produces hydrogen by photocatalytic water splitting under solar light. The hydrogen fuel is then consumed by the μFC to generate electricity. Importantly, the by-product water returns back to the photocatalytic μFG via recirculation loop without losses. Both devices rely on novel phenomena in extended-nano-fluidic channels that ensure ultra-fast proton transport. As a proof of concept, we demonstrate that μFG/μFC source achieves remarkable energy density of ca. 17.2 mWh cm−2 at room temperature.  相似文献   

17.
Sorbent particles consisting of nano and micro silica, and micron size octadecylsilica (ODS) were immobilized using sol-gel chemistry onto poly(dimethylsiloxane) (PDMS) microfluidic channels to serve as μ-chip solid phase extraction (SPE) devices. Extraction, preconcentration and purification of biological and chemical analytes were carried out using these. Micro and nano scale silica-immobilized μ-SPE were used for the extraction/purification of DNA from recombinant Escherichia coli crude lysate. The average DNA recovery was 77 ± 9% (X ± R.S.D.) for the micron size silica particles and 70 ± 5% (X ± R.S.D.) for the nano silica particles. The extracted DNA could be amplified by polymerase chain reaction (PCR) whereas the DNA from the crude lysate solution could not be. This was a testimony to the purification capability of the μ-SPE device. ODS immobilized μ-SPE were used to study the extraction efficiency (EE) and enhancement factor (EF) for three groups of organic compounds, aromatics, phenols and carboxylic acids. They showed poor recovery and low enrichment because the analytes sorbed into the PDMS and were not quantitatively extracted.  相似文献   

18.
A method to continuously separate different particle types in a suspension is reported. Acoustic forces in a standing wave field were utilized to discriminate lipid particles from erythrocytes in whole blood. The presented technology proposes a new method of cleaning, i.e. removing lipid emboli from, shed blood recovered during cardiac surgery. Blood contaminated with lipid particles enter a laminar flow micro channel. Erythrocytes and lipid particles suspended in blood plasma are exposed to a half wavelength standing wave field orthogonal to the direction of flow as they pass through the channel. Because of differences in compressibility and density the two particle types move in different directions, the erythrocytes towards the centre of the channel and the lipid particles towards the side walls. The end of the channel is split into three outlet channels conducting the erythrocytes to the centre outlet and the lipid particles to the side outlets due to the laminar flow profile. The separation channel was evaluated in vitro using polyamide spheres suspended in water, showing separation efficiencies approaching 100%. The system was also evaluated on whole blood using tritium labelled lipid particles added to bovine blood. More than 80% of the lipid particles could be removed while approximately 70% of the erythrocytes were collected in one third of the original fluid volume. The study showed that the further reduced micro channel dimensions provided improved performance with respect to; (i) separation efficiency, (ii) actuation voltage, and (iii) volumetric throughput as compared to earlier work.  相似文献   

19.
Protein channels on the biofilm conditionally manipulate ion transport via regulating the distribution of charge residues, making analogous processes on artificial membranes a hot spot and challenge. Here, we employ metal–organic frameworks (MOFs) membrane with charge-adjustable subnano-channel to selectively govern ion transport. Various valent ions are binded with crown ethers embedded in the MOF cavity, which act as charged guest to regulate the channels’ charge state from the negativity to positivity. Compared with the negatively charged channel, the positive counterpart obviously enhances Li+/Mg2+ selectivity, which benefit from the reinforcement of the electrostatic repulsion between ions and the channel. Meanwhile, theoretical calculations reveal that Mg2+ transport through the more positively charged channel needed to overcome higher entrance energy barrier than that of Li+. This work provides a subtle strategy for ion-selective transport upon regulating the charge state of insulating membrane, which paves the way for the application like seawater desalination and lithium extraction from salt lakes.  相似文献   

20.

Most water in the world is as saline water in seas and oceans. Desalination technology is a promising method to solve the global water crisis. Recently, many attentions have been paid to the graphene-based membranes in water desalination due to their low production cost and high efficiency. In this paper, molecular dynamics simulations are employed to investigate the effect of functionalized graphene nanosheet (GNS) membranes on the performance of salt separation from seawater in terms of water permeability and salt rejection. For this purpose, the hydrogenated (–H) and fluorinated (–F) pores were created on the GNS membrane. Then, the functionalized graphene membrane was placed in the middle of the simulation box in an aqueous ionic solution containing Na+ and Cl? ions. The applied pressure (in the range of 10–100 MPa) was used as the driving force for transport of water molecules across the reverse osmosis (RO) graphene-based membrane in order to obtain the water permeability and salt rejection. Also, radial distribution functions (RDFs) of ion–water and water–water as well as the water density map around the membrane were obtained. The results indicated that the hydrophilic chemical functions such as fluorine (–F) can improve the water permeability at low pressures.

  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号