Improving Aptamer Selection Efficiency through Volume Dilution, Magnetic Concentration, and Continuous Washing in Microfluidic Channels

This paper describes the reconfiguration of molecular tunneling junctions during operation via the self-assembly of bilayers of glycol ethers. We use well-established functional groups to modulate the magnitude and direction of rectification in assembled tunneling junctions by exposing them to solutions containing different glycol ethers. Variable-temperature measurements establish that rectification occurs by a bias-dependent tunneling-hopping mechanism and that glycol ethers, beside being an unusually efficient tunneling medium, behave identically to alkanes. We fabricated memory bits from crossbar junctions prepared by injecting eutectic Ga-In into microfluidic channels. Two 8-bit registers were able to perform logical AND operations on bit strings encoded into chemical packets as microfluidic droplets that alter the composition of the crossbar junctions through self-assembly to effect memristor-like properties. This proof of concept work demonstrates the potential for fieldable molecular-electronic devices based on tunneling junctions of self-assembled monolayers and bilayers.

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3-D Printing Microfluidic Channels With Embedded Planar Microwave Resonators for RFID and Liquid Detection

IEEE Microwave and Wireless Components Letters ◽

10.1109/lmwc.2018.2883715 ◽

2019 ◽

Vol 29 (1) ◽

pp. 65-67 ◽

Cited By ~ 20

Author(s):

Benjamin D. Wiltshire ◽

Mohammad H. Zarifi

Keyword(s):

Microfluidic Channels ◽

Microwave Resonators ◽

Liquid Detection

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Studying dynamic stress effects on the behaviour of THP-1 cells by microfluidic channels

Scientific Reports ◽

10.1038/s41598-021-93935-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Semra Zuhal Birol ◽

Rana Fucucuoglu ◽

Sertac Cadirci ◽

Ayca Sayi-Yazgan ◽

Levent Trabzon

Keyword(s):

Endothelial Cells ◽

Shear Stress ◽

Vascular System ◽

Circulatory System ◽

Disease Process ◽

Microfluidic Channels ◽

Shear Stresses ◽

Stress Effects ◽

Adhesion Behavior ◽

Cycling System

AbstractAtherosclerosis is a long-term disease process of the vascular system that is characterized by the formation of atherosclerotic plaques, which are inflammatory regions on medium and large-sized arteries. There are many factors contributing to plaque formation, such as changes in shear stress levels, rupture of endothelial cells, accumulation of lipids, and recruitment of leukocytes. Shear stress is one of the main factors that regulates the homeostasis of the circulatory system; therefore, sudden and chronic changes in shear stress may cause severe pathological conditions. In this study, microfluidic channels with cavitations were designed to mimic the shape of the atherosclerotic blood vessel, where the shear stress and pressure difference depend on design of the microchannels. Changes in the inflammatory-related molecules ICAM-1 and IL-8 were investigated in THP-1 cells in response to applied shear stresses in an continuous cycling system through microfluidic channels with periodic cavitations. ICAM-1 mRNA expression and IL-8 release were analyzed by qRT-PCR and ELISA, respectively. Additionally, the adhesion behavior of sheared THP-1 cells to endothelial cells was examined by fluorescence microscopy. The results showed that 15 Pa shear stress significantly increases expression of ICAM-1 gene and IL-8 release in THP-1 cells, whereas it decreases the adhesion between THP-1 cells and endothelial cells.

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Microfluidic channels of adjustable height using deformable elastomer

Microfluidics and Nanofluidics ◽

10.1007/s10404-020-02408-5 ◽

2021 ◽

Vol 25 (1) ◽

Author(s):

Dandara Velasco Anez ◽

Celine Hadji ◽

Enric Santanach-Carreras ◽

Elise Lorenceau ◽

Cyril Picard

Keyword(s):

Microfluidic Channels

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Photothermal slippery surfaces towards spatial droplets manipulation

Journal of Materials Chemistry A ◽

10.1039/d1ta04243b ◽

2021 ◽

Author(s):

Keyu Han ◽

Zubin Wang ◽

Liping Heng ◽

Lei Jiang

Keyword(s):

Microfluidic Channels ◽

Fundamental Research

Intelligent responsive slippery surfaces with adjustable wettability present considerable significance in a broad range of fundamental research and application realms including microfluidic channels, microreactions, and liquid directional-conveying devices. Although considerable...

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Droplet breakup mechanisms in premix membrane emulsification and microfluidic channels

Advances in Colloid and Interface Science ◽

10.1016/j.cis.2021.102393 ◽

2021 ◽

pp. 102393

Author(s):

Akmal Nazir ◽

Goran T. Vladisavljević

Keyword(s):

Droplet Breakup ◽

Microfluidic Channels ◽

Membrane Emulsification ◽

Premix Membrane Emulsification

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Impact of cigarette versus electronic cigarette aerosol conditioned media on aortic endothelial cells in a microfluidic cardiovascular model

Scientific Reports ◽

10.1038/s41598-021-83511-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Om Makwana ◽

Gina A. Smith ◽

Hannah E. Flockton ◽

Gary P. Watters ◽

Frazer Lowe ◽

...

Keyword(s):

Endothelial Cells ◽

Human Monocyte ◽

Conditioned Media ◽

Electronic Cigarette ◽

Microfluidic Channels ◽

Adhesion Assay ◽

Monocyte Adhesion ◽

Aortic Endothelial Cells ◽

Aortic Endothelial

AbstractAtherosclerosis is a complex process involving progressive pathological events, including monocyte adhesion to the luminal endothelial surface. We have developed a functional in vitro adhesion assay using BioFlux microfluidic technology to investigate THP-1 (human acute monocytic leukaemia cell) monocyte adhesion to human aortic endothelial cells (HAECs). The effect of whole smoke conditioned media (WSCM) generated from University of Kentucky reference cigarette 3R4F, electronic cigarette vapour conditioned media (eVCM) from an electronic nicotine delivery system (ENDS) product (Vype ePen) and nicotine on monocyte adhesion to HAECs was evaluated. Endothelial monolayers were grown in microfluidic channels and exposed to 0–1500 ng/mL nicotine or nicotine equivalence of WSCM or eVCM for 24 h. Activated THP-1 cells were perfused through the channels and a perfusion, adhesion period and wash cycle performed four times with increasing adhesion period lengths (10, 20, 30 and 40 min). THP-1 cell adhesion was quantified by counting adherent cells. WSCM induced dose-dependent increases in monocyte adhesion compared to vehicle control. No such increases were observed for eVCM or nicotine. Adhesion regulation was linked to increased ICAM-1 protein expression. Staining of ICAM-1 in HAECs and CD11b (MAC-1) in THP-1 cells demonstrated adhesion molecule co-localisation in BioFlux plates. The ICAM-1 adhesion response to WSCM was downregulated by transfecting HAECs with ICAM-1 siRNA. We conclude that the BioFlux system is able to model human monocyte adhesion to primary human endothelial cells in vitro and WSCM drives the greatest increase in monocyte adhesion via a mechanism involving endothelial ICAM-1 expression.

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Visualization of Surface Acoustic Waves in Thin Liquid Films

Scientific Reports ◽

10.1038/srep21980 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 20

Author(s):

R. W. Rambach ◽

J. Taiber ◽

C. M. L. Scheck ◽

C. Meyer ◽

J. Reboud ◽

...

Keyword(s):

Liquid Film ◽

Acoustic Waves ◽

Low Cost ◽

Thin Liquid Film ◽

Surface Acoustic Waves ◽

Liquid Films ◽

Theoretical Description ◽

Propagation Path ◽

Microfluidic Channels ◽

Potential Applications

Abstract We demonstrate that the propagation path of a surface acoustic wave (SAW), excited with an interdigitated transducer (IDT), can be visualized using a thin liquid film dispensed onto a lithium niobate (LiNbO3) substrate. The practical advantages of this visualization method are its rapid and simple implementation, with many potential applications including in characterising acoustic pumping within microfluidic channels. It also enables low-cost characterisation of IDT designs thereby allowing the determination of anisotropy and orientation of the piezoelectric substrate without the requirement for sophisticated and expensive equipment. Here, we show that the optical visibility of the sound path critically depends on the physical properties of the liquid film and identify heptane and methanol as most contrast rich solvents for visualization of SAW. We also provide a detailed theoretical description of this effect.

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