Cell Assays in Microfluidics

Cell Assays in Microfluidics Cell Culture (2D and 3D) on Chip... 

Cell assays fall into four broad themes sorted as a function of the type of response to be measured intracellular biochemistry, extracellular biochemistry, mechanical properties, and electrical properties. Prior to discussing these kinds of assays, the basic methodology common to all forms of cell assays in microfluidics devices is described. 

Stimuli used for cell assays in microfluidic devices can be categorized into two main groups ... 

Cell assays in microfluidics can be classified into four themes intracellular biochemistry, extracellular biochemistry, mechaiucal properties, and electrical properties. 

Cell Assays in Microfluidics, Fig. 2 (a) Digital microfluidic cell assay In 150 nL droplets containing 525 Jurkat T-cells per droplet. Fluorescent images of cells show almost all cells live (top) when treated with 0 % surfactant Tween 20 and all cells dead bottom) when treated with 0.5 % Tween 20 (Image reproduced, with... 

Cell Adhesion and Detachment Cell Assays in Microfluidics Cell Patterning on Chip Droplet Microreactor... 

While an array of analytical techniques has been developed to study various aspects of cells (please see Cell Assays in Microfluidics), this entiy is focused on chemical cytometry. As mentioned above, chemical cytometry refers to methods in which intracellular constituents of a single cell are analyzed by means of a chemical separation. Such methods typically employ capillary electrophoresis for separations, combined with laser-induced fluorescence (LIF) or amperometry for detection. We refer readers to other entries for detailed descriptions of other methods used to evaluate the contents of cells ( Patch Clamp Measurements On-Chip, Mass Spectrometry on a Chip). 

Li and Harrison carried out the first cell assay in microchannels [2]. This seminal work made use of electrokinetically driven flow (electroosmosis and electrophoresis) to transport bacteria, yeast, and mammalian cells in channels and to implement low-volume chemical lysis (cell death). This theme of microfluidics-based cell transport, sorting, and lysis, has continued to be a popular application, as well as related work in using microfluidics to culture cells and to pattern them into structures. We acknowledge the utility of these methods (and note that they are featured in several good reviews - see El-Ali et al. [1] and other entries in the Encyclopedia), but focus here on describing microfluidics-based cell assays that fit the definition described above - application of a stimulus and measurement of a response. These assays fall into four broad themes sorted as a function of the t)fpe of response to be measured intracellular biochemistry, extracellular biochemistry, mechanical properties, and electrical properties. Prior to discussing these kinds of assays, we describe the basic methodology common to all forms of cell assays in microfluidics devices. 

Cell Assays in Microfluidics, Figure 1 (a) MFF11 cell line grown In microfluidic V-channels for monitoring intracellular reporter gene activity. (Image... 

Cell Assays in Microfluidics, Figure 3 (a) Schematic of a device for... 

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