Numerical and Microfluidic-Based Cell-Sorting Devices

2007 ◽  
Author(s):  
Jay K. Taylor ◽  
Carolyn L. Ren ◽  
G. D. Stubley
Keyword(s):  
Flow Field ◽  
Flow Control ◽  
Cell Sorting ◽  
High Efficiency ◽  
Lab On A Chip ◽  
Polymeric Materials ◽  
Chip Design ◽  
Pressure Disturbance ◽  
Chip Technology ◽  
Channel Blockage

The development of Lab-on-a-Chip devices with integrated bio-analysis functions requires a complex network of microfluidic transport and processes. Many of these functions call for the isolation or separation of specific bio-particles or cells. The design of a miniaturized cell-sorting device for handheld operation must follow the strict parameters associated with Lab-on-a-Chip technology. The limitations include applied voltage, high efficiency of cell-separation, repeatability, size, flow control, and cost, among others. Currently used designs have achieved successful levels of cell-isolation. However, further improvements in the microfluidic chip design are important for incorporation into larger systems. This study evaluates specific design modifications that contribute to the reduction of required applied potential aiming for developing portable devices, improved operation reliability by minimizing induced pressure disturbance when electrokinetic pumping is employed and incorporating online filters to reduce channel blockage, and improved flow control by incorporating directing streams achieving dynamic sorting and counting. The chip designs fabricated in glass and polymeric materials include asymmetric channel widths for sample focusing, nonuniform channel depth for minimizing induced pressure disturbance, directing streams to assist particle flow control, and online filters for reducing channel blockage. Fluorescence-based visualization of electrokinetic focusing, flow field phenomena, and dynamic cell-sorting demonstrate the advantages of the chip design. Numerical simulations in COMSOL are validated by the experimental data and used to investigate the effects of channel geometry and fluid properties on the flow field.

Applications to Cancer Research of “Lab-on-a-chip” Devices Based on Dielectrophoresis (DEP)

2003 ◽  
Vol 2 (1) ◽  
pp. 31-39 ◽  
Author(s):  
Roberto Gambari ◽  
Monica Borgatti ◽  
Luigi Altomare ◽  
Nicolo Manaresi ◽  
Gianni Medoro ◽  
...  
Keyword(s):  
Cancer Research ◽  
High Efficiency ◽  
Drug Research ◽  
Lab On A Chip ◽  
Strategic Objectives ◽  
Analytical Instruments ◽  
Chip Technology ◽  
Analytical Procedures ◽  
Application Fields ◽  
New Generation

The recent development of advanced analytical and bioseparation methodologies based on microarrays and biosensors is one of the strategic objectives of the so-called post-genomic. In this field, the development of microfabricated devices could bring new opportunities in several application fields, such as predictive oncology, diagnostics and anti-tumor drug research. The so called “Laboratory-on-a-chip technology”, involving miniaturisation of analytical procedures, is expected to enable highly complex laboratory testing to move from the central laboratory into non-laboratory settings. The main advantages of Lab-on-a-chip devices are integration of multiple steps of different analytical procedures, large variety of applications, sub-microliter consumption of reagents and samples, and portability. One of the requirement for new generation Lab-on-a-chip devices is the possibility to be independent from additional preparative/analytical instruments. Ideally, Lab-on-a-chip devices should be able to perform with high efficiency and reproducibility both actuating and sensing procedures. In this review, we discuss applications of dielectrophoretic(DEP)-based Lab-on-a-chip devices to cancer research. The theory of dielectrophoresis as well as the description of several devices, based on spiral-shaped, parallel and arrayed electrodes are here presented. In addition, in this review we describe manipulation of cancer cells using advanced DEP-based Lab-on-a-chip devices in the absence of fluid flow and with the integration of both actuating and sensing procedures.

scholarly journals Recent Advancements in Polythiophene-Based Materials and Their Biomedical, Geno Sensor and DNA Detection

2021 ◽  
Vol 22 (13) ◽  
pp. 6850
Author(s):  
Seyyed Mojtaba Mousavi ◽  
Seyyed Alireza Hashemi ◽  
Sonia Bahrani ◽  
Khadije Yousefi ◽  
Gity Behbudi ◽  
...  
Keyword(s):  
Biomedical Engineering ◽  
High Efficiency ◽  
Polymeric Materials ◽  
The Novel ◽  
Electrode Coating ◽  
Effective Response ◽  
Hiv Drugs ◽  
New Generation ◽  
New Compounds ◽  
Anti Hiv

In this review, the unique properties of intrinsically conducting polymer (ICP) in biomedical engineering fields are summarized. Polythiophene and its valuable derivatives are known as potent materials that can broadly be applied in biosensors, DNA, and gene delivery applications. Moreover, this material plays a basic role in curing and promoting anti-HIV drugs. Some of the thiophene’s derivatives were chosen for different experiments and investigations to study their behavior and effects while binding with different materials and establishing new compounds. Many methods were considered for electrode coating and the conversion of thiophene to different monomers to improve their functions and to use them for a new generation of novel medical usages. It is believed that polythiophenes and their derivatives can be used in the future as a substitute for many old-fashioned ways of creating chemical biosensors polymeric materials and also drugs with lower side effects yet having a more effective response. It can be noted that syncing biochemistry with biomedical engineering will lead to a new generation of science, especially one that involves high-efficiency polymers. Therefore, since polythiophene can be customized with many derivatives, some of the novel combinations are covered in this review.

Flow-Field-Assisted Dielectrophoretic Microchips for High-Efficiency Sheathless Particle/Cell Separation with Dual Mode

2021 ◽  
Author(s):  
Shitao Shen ◽  
Zichuan Yi ◽  
Xing Li ◽  
Shuting Xie ◽  
Mingliang Jin ◽  
...  
Keyword(s):  
Flow Field ◽  
Cell Separation ◽  
High Efficiency ◽  
Dual Mode

scholarly journals Testing Lab-on-a-Chip Technology for Culturing Human Melanoma Cells under Simulated Microgravity

Cancers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 402
Author(s):  
Dawid Przystupski ◽  
Agata Górska ◽  
Olga Michel ◽  
Agnieszka Podwin ◽  
Patrycja Śniadek ◽  
...  
Keyword(s):  
Simulated Microgravity ◽  
Lab On A Chip ◽  
Human Keratinocytes ◽  
Melanoma Cells ◽  
Short Exposure ◽  
Biological Research ◽  
Cell Physiology ◽  
Caspase Activity ◽  
Chip Technology ◽  
Cells Cultured

The dynamic development of the space industry makes space flights more accessible and opens up new opportunities for biological research to better understand cell physiology under real microgravity. Whereas specialized studies in space remain out of our reach, preliminary experiments can be performed on Earth under simulated microgravity (sµg). Based on this concept, we used a 3D-clinostat (3D-C) to analyze the effect of short exposure to sµg on human keratinocytes HaCaT and melanoma cells A375 cultured on all-glass Lab-on-a-Chip (LOC). Our preliminary studies included viability evaluation, mitochondrial and caspase activity, and proliferation assay, enabling us to determine the effect of sµg on human cells. By comparing the results concerning cells cultured on LOCs and standard culture dishes, we were able to confirm the biocompatibility of all-glass LOCs and their potential application in microgravity research on selected human cell lines. Our studies revealed that HaCaT and A375 cells are susceptible to simulated microgravity; however, we observed an increased caspase activity and a decrease of proliferation in cancer cells cultured on LOCs in comparison to standard cell cultures. These results are an excellent basis to conduct further research on the possible application of LOCs systems in cancer research in space.

scholarly journals Model-Based Analysis of Flow Separation Control in a Curved Diffuser by a Vibration Wall

Energies ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1781
Author(s):  
Weiyu Lu ◽  
Xin Fu ◽  
Jinchun Wang ◽  
Yuanchi Zou
Keyword(s):  
Flow Field ◽  
Flow Control ◽  
Flow Separation ◽  
Vibration Frequency ◽  
Flow Instability ◽  
Control Technique ◽  
Simplified Model ◽  
Main Stream ◽  
Control Performance ◽  
Flow Separation Control

Vibration wall control is an important active flow control technique studied by many researchers. Although current researches have shown that the control performance is greatly affected by the frequency and amplitude of the vibration wall, the mechanism hiding behind the phenomena is still not clear, due to the complex interaction between the vibration wall and flow separation. To reveal the control mechanism of vibration walls, we propose a simplified model to help us understand the interaction between the forced excitation (from the vibration wall) and self-excitation (from flow instability). The simplified model can explain vibration wall flow control behaviors obtained by numerical simulation, which show that the control performance will be optimized at a certain reduced vibration frequency or amplitude. Also, it is shown by the analysis of maximal Lyapunov exponents that the vibration wall is able to change the flow field from a disordered one into an ordered one. Consistent with these phenomena and bringing more physical insight, the simplified model implies that the tuned vibration frequency and amplitude will lock in the unsteady flow separation, promote momentum transfer from the main stream to the separation zone, and make the flow field more orderly and less chaotic, resulting in a reduction of flow loss.

Experimental Investigations on the Efficiency of Active Flow Control in a Compressor Cascade With Periodic Non-Steady Outflow Conditions

2017 ◽  
Author(s):  
Marcel Staats ◽  
Wolfgang Nitsche
Keyword(s):  
Flow Field ◽  
Flow Control ◽  
Flow Separation ◽  
Active Flow Control ◽  
Experimental Investigations ◽  
Compressor Cascade ◽  
Steady Regime ◽  
Stator Blade ◽  
Active Flow ◽  
The Impact

We present results of experiments on a periodically unsteady compressor stator flow of the type which would be expected in consequence of pulsed combustion. A Reynolds number of Re = 600000 was used for the investigations. The experiments were conducted on the two-dimensional low-speed compressor testing facility in Berlin. A choking device downstream the trailing edges induced a periodic non-steady outflow condition to each stator vane which simulated the impact of a pressure gaining combuster downstream from the last stator. The Strouhal number of the periodic disturbance was Sr = 0.03 w.r.t. the stator chord length. Due to the periodic non-steady outflow condition, the flow-field suffers from periodic flow separation phenomena, which were managed by means of active flow control. In our case, active control of the corner separation was applied using fluidic actuators based on the principle of fluidic amplification. The flow separation on the centre region of the stator blade was suppressed by means of a fluidic blade actuator leading to an overall time-averaged loss reduction of 11.5%, increasing the static pressure recovery by 6.8% while operating in the non-steady regime. Pressure measurements on the stator blade and the wake as well as PIV data proved the beneficial effect of the active flow control application to the flow field and the improvement of the compressor characteristics. The actuation efficiency was evaluated by two figures of merit introduced in this contribution.

Fabrication and testing of hydrogel-based microvalves for flow control in flexible lab-on-a-chip systems

2012 ◽  
Author(s):  
Ang Li ◽  
Jonathan Lee ◽  
Bonnie L. Gray ◽  
Paul C. H. Li
Keyword(s):  
Flow Control ◽  
Lab On A Chip

scholarly journals Lab-on-a-chip technology and microfluidics

2019 ◽  
pp. 3-36 ◽  
Author(s):  
Antonio Francesko ◽  
Vanessa F. Cardoso ◽  
Senentxu Lanceros-Méndez
Keyword(s):  
Lab On A Chip ◽  
Chip Technology
Sign in / Sign up

Export Citation Format

Share Document