Manipulating Cells, Techniques

Manipulating Cells, Techniques, Table 1 Classification of the techniques for manipulating cells by physical mechanisms employed... 

Genetic engineering techniques manipulate cells to express and/or alter cloned genes. 

Another way of regulating fluid flow for noncontact component manipulation was created by mechanical oscillation. Within a fluid environment, a tool capable of oscillating its tip at high frequencies would then create local streamlined flow. Tool oscillation parameters could be adjusted to define whether the local flow would repel, attract, or rotate components. For this technique, there was no contact between the tool and the manipulated component. This concept is attractive for manipulating cells and live organisms [5]. 

Different techniques for manipulating cells in microfluidic devices have been proposed for a wide variety of applications. The purpose of this essay is to systematize the techniques by the physical principles and forces used for controlling cell position. The reader is encouraged to follow the links to chapters describing in more detail how the interaction between cells and mechanical and biochemical entities or with electric, magnetic, or optical fields can be implemented at microscale for the handling of cells for various applications (Table 1). 

The implementation of physical mechanisms at the microscale for cell manipulation takes advantage of the scaling laws at sizes comparable to cells sizes. Some of the techniques are widely used and very well developed (see the entries on Cell Patterning on Chip, Dielectrophoretic Motion of Particles and Cells, Optical Tweezers for Manipulating Cells and Particles ). Other techniques are still emerging and our understanding of the practical aspects of these is still evolving. 

These optical methods, though, have been developed to include image projectors to manipulate cells using larger, patterned illumination areas. For example, virtual structures can be used to direct cells or can be alternatively used to pattern trapped cells. An investigation of optically induced dielectrophoresis for cellular manipulation is found in detail elsewhere [8]. This investigation characterizes the controllability of these optical techniques. This technique, though, should not be confused with opti-... 

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