Nanoliters Discharge/Suction by Thermoresponsive Polymer Actuated Probe and Applied for Single Cell Manipulation

We propose the Thermoresponsive Polymer Actuated (TPA) probe which uses thermoresponsive polymer poly (N-isopropylacrylamide) (PNIPAAm) volume change as an actuator. The proposed probe is applicable to single cell analysis, especially single cell manipulation. The TPA probe can discharge and suck solution in several nanoliters (nl) using the volume change. Normally, it is difficult to realize solution discharge and suction less than several dozen nl by the conventional air- or oil-pressure-actuated probe. We designed the TPA probe for low-cost fabrication and disposable use. The probe also takes in and ejects on a nl order by simply switching a heater on and off. PNIPAAm solution volume change was evaluated in this paper. The manipulation of single microbead and the suction of target cell were also demonstrated by the TPA probe in the semi-closed microchip. It is considered that the TPA probe can contribute to the manipulation of single cell.

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Microfluidic Single-Cell Manipulation and Analysis: Methods and Applications

Micromachines ◽

10.3390/mi10020104 ◽

2019 ◽

Vol 10 (2) ◽

pp. 104 ◽

Cited By ~ 38

Author(s):

Tao Luo ◽

Lei Fan ◽

Rong Zhu ◽

Dong Sun

Keyword(s):

Single Cell ◽

Single Cell Analysis ◽

Single Cells ◽

Petri Dish ◽

Cell Manipulation ◽

Single Cell Level ◽

Cell Analysis ◽

Cell Level ◽

Advantages And Disadvantages ◽

Single Cell Manipulation

In a forest of a hundred thousand trees, no two leaves are alike. Similarly, no two cells in a genetically identical group are the same. This heterogeneity at the single-cell level has been recognized to be vital for the correct interpretation of diagnostic and therapeutic results of diseases, but has been masked for a long time by studying average responses from a population. To comprehensively understand cell heterogeneity, diverse manipulation and comprehensive analysis of cells at the single-cell level are demanded. However, using traditional biological tools, such as petri-dishes and well-plates, is technically challengeable for manipulating and analyzing single-cells with small size and low concentration of target biomolecules. With the development of microfluidics, which is a technology of manipulating and controlling fluids in the range of micro- to pico-liters in networks of channels with dimensions from tens to hundreds of microns, single-cell study has been blooming for almost two decades. Comparing to conventional petri-dish or well-plate experiments, microfluidic single-cell analysis offers advantages of higher throughput, smaller sample volume, automatic sample processing, and lower contamination risk, etc., which made microfluidics an ideal technology for conducting statically meaningful single-cell research. In this review, we will summarize the advances of microfluidics for single-cell manipulation and analysis from the aspects of methods and applications. First, various methods, such as hydrodynamic and electrical approaches, for microfluidic single-cell manipulation will be summarized. Second, single-cell analysis ranging from cellular to genetic level by using microfluidic technology is summarized. Last, we will also discuss the advantages and disadvantages of various microfluidic methods for single-cell manipulation, and then outlook the trend of microfluidic single-cell analysis.

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Microscale Oil-Covered Cell Array (MOCCA): A Droplet Array for High-Content Single-Cell Analysis and Imaging

ASME 2009 7th International Conference on Nanochannels, Microchannels and Minichannels ◽

10.1115/icnmm2009-82283 ◽

2009 ◽

Author(s):

Liang-I Lin ◽

Shih-Hui Chao ◽

Deirdre R. Meldrum

Keyword(s):

Single Cell ◽

Single Cell Analysis ◽

Low Cost ◽

Cell Number ◽

Cell Analysis ◽

Cell Array ◽

Flat Substrate ◽

Fabrication Procedure ◽

Droplet Array ◽

The Cost

A simple, low-cost technique for high throughput single-cell analysis, Microscale Oil-Covered Cell Array (MOCCA), is presented in this paper. Corresponding to recent research on single cell analysis, simple devices for isolated cell chambers are urgently needed and long sought-after. Instead of using microfabricated solid structures to capture cells, MOCCA isolates cells in discrete aqueous droplets that are separated by oil on the patterned hydrophilic areas on a relatively more hydrophobic flat substrate. In our pioneer study, we created an array of 700-picoliter droplets. The randomly seeded E. coli cell number in each discrete droplet approaches single-cell levels. The total time needed for MOCCA fabrication was no more than 10 minutes. Compared to traditional micro-fabrication techniques, MOCCA dramatically lowers the cost and enhances the efficiency for the fabrication procedure, while producing a microscale array as in those made using traditional methods.

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Dielectrophoresis Tweezers for Single Cell Manipulation Using Metal Coated Chemically Etched Fiber

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.625.678 ◽

2014 ◽

Vol 625 ◽

pp. 678-682

Author(s):

Kozo Taguchi ◽

Keishu Aritoshi ◽

Kyohei Nishimoto ◽

Shun Fukutomi

Keyword(s):

Single Cell ◽

Low Cost ◽

Yeast Cells ◽

Cell Manipulation ◽

Signal Frequency ◽

Experimental Investigations ◽

Target Cells ◽

Promising Tool ◽

Single Target ◽

Single Cell Manipulation

We proposed a simple and low cost dielectrophoretic device to trap and isolate single target cells. The device consisted of a metal coated chemically etched fiber and an AC signal generator. It did not require microfabrication technologies or sophisticated electronics. Using this system, we could easily trap and isolate yeast cells at will. Furthermore, our dielectrophoretic manipulator also could discriminate between live and dead cells by tuning of the applied signal frequency. From these experimental investigations, it was found that our proposed dielectrophoresis tweezers using metal coated chemically etched fiber was a promising tool for the single cell manipulation and isolation.

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An automated real-time microfluidic platform to probe single NK cell heterogeneity and cytotoxicity on-chip

Scientific Reports ◽

10.1038/s41598-021-96609-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Nikita Subedi ◽

Laura C. Van Eyndhoven ◽

Ayla M. Hokke ◽

Lars Houben ◽

Mark C. Van Turnhout ◽

...

Keyword(s):

Nk Cells ◽

Single Cell ◽

Real Time ◽

Target Cell ◽

Single Cell Analysis ◽

Nk Cell ◽

Cell Interactions ◽

Cellular Interaction ◽

Cell Analysis ◽

Microfluidic Platform

AbstractCytotoxicity is a vital effector mechanism used by immune cells to combat pathogens and cancer cells. While conventional cytotoxicity assays rely on averaged end-point measures, crucial insights on the dynamics and heterogeneity of effector and target cell interactions cannot be extracted, emphasizing the need for dynamic single-cell analysis. Here, we present a fully automated droplet-based microfluidic platform that allowed the real-time monitoring of effector-target cell interactions and killing, allowing the screening of over 60,000 droplets identifying 2000 individual cellular interactions monitored over 10 h. During the course of incubation, we observed that the dynamics of cytotoxicity within the Natural Killer (NK) cell population varies significantly over the time. Around 20% of the total NK cells in droplets showed positive cytotoxicity against paired K562 cells, most of which was exhibited within first 4 h of cellular interaction. Using our single cell analysis platform, we demonstrated that the population of NK cells is composed of individual cells with different strength in their effector functions, a behavior masked in conventional studies. Moreover, the versatility of our platform will allow the dynamic and resolved study of interactions between immune cell types and the finding and characterization of functional sub-populations, opening novel ways towards both fundamental and translational research.

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Development of an Inverted Epifluorescence Microscope for Long-Term Monitoring of Bacteria in Multiplexed Microfluidic Devices

Sensors ◽

10.3390/s20154140 ◽

2020 ◽

Vol 20 (15) ◽

pp. 4140

Author(s):

Amaro Torres-Simón ◽

María Henar Marino ◽

Clara Gómez-Cruz ◽

Marina Cañadas ◽

Miguel Marco ◽

...

Keyword(s):

Single Cell ◽

Bacterial Resistance ◽

Single Cell Analysis ◽

Low Cost ◽

Microfluidic Devices ◽

Cell Analysis ◽

Antibiotic Development ◽

Long Term Monitoring ◽

Term Monitoring

Developing more efficient methods for antibiotic susceptibility testing is a pressing issue in novel drug development as bacterial resistance to antibiotics becomes increasingly common. Microfluidic devices have been demonstrated to be powerful platforms that allow researchers to perform multiplexed antibiotic testing. However, the level of multiplexing within microdevices is limited, evidencing the need of creating simple, low-cost and high-resolution imaging systems that can be integrated in antibiotic development pipelines. This paper describes the design and development of an epifluorescence inverted microscope that enables long-term monitoring of bacteria inside multiplexed microfluidic devices. The goal of this work is to provide a simple microscope powerful enough to allow single-cell analysis of bacteria at a reduced cost. This facilitates increasing the number of microscopes that are simultaneously used for antibiotic testing. We prove that the designed system is able to accurately detect fluorescent beads of 100 nm, demonstrating comparable features to high-end commercial microscopes and effectively achieving the resolution required for single-cell analysis of bacteria. The proposed microscope could thus increase the efficiency in antibiotic testing while reducing cost, size, weight, and power requirements, contributing to the successful development of new antibiotic drugs.

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