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Biologically Inspired Robotics
as well as on retrieval of living cells into microfluidic devices and their
manipulation thereafter. Automated continuous individual cell transfer is
a critical step in single-cell applications using microfluidic devices. Cells
must be aspirated gently from a buffer before transferring to an operation
zone to avoid artificially perturbing their biostructures. Vision-based
manipulation is a key sensing technique that allows nondestructive
cell detection. In this chapter, we present a design for an automated single-cell transfer module that can be integrated with complex microfluidic
applications that examine or process one cell at a time such as the current
nuclear transplantation method. The aim of the system is to automatically transfer mammalian fibroblasts (~15 μm) or oocytes (~100 μm) one
by one from a container to a polydimethylsiloxane (PDMS) microchannel
and then transport them to other modules. The system consists of two
main parts: a single-cell suction module and a disposable PDMS-based
microfluidic chip controlled by external pumps. The desired number of
vacuumed cells can be directed into the microfluidic chip and stored in
a docking area. From the batch, they can be moved to the next module
by activating pneumatic pressure valves located on two sides of the chip.
The entire mechanism is combined with monitoring systems that perform the detection/tracking and control program.
7.1 Introduction
Microfluidic technology and its applications are extensive and have many
significant advantages, bringing the benefits of miniaturization, integration, and automation to biotechnology-related studies over the past several
decades (Jager, Inganäs, and LundstrÖm 2000; Vilkner, Janasek, and Manz
2004). Microfluidic-based technology offers a convenient platform for cellular analyses of biological systems, because the small scale of microchannels and devices allows producing scalable system architectures (Unger et
al. 2000; Walker, Zeringu, and Beebe 2004). Their inexpensive composition
makes them a potential candidate for large-scale production. Microfluidic
technology covers not only the material phenomena but also the technology
for manipulating and controlling the components as microsize particles in
microsize artificial capillaries. Therefore, the integration of these technologies with microrobotic applications could be useful in the automation of cell
manipulation for important areas such as single-cell analysis, manipulation,
and treatment, including nuclear transplantation (Cui et al. 2001; Lee et al.
2003; Ramesham and Ghaffarian 2000; Schwarz and Hauser 2001).
Integration of cell treatment steps is crucial to developing microfluidic
devices for analysis of cell constituents, cell lysis, and cell culture (Elfwing
et al. 2004; Schonholzer et al. 2002). For example, experimental results
show that microfluidic technology provides a significant advantage in the
Biologically Inspired Robotics
as well as on retrieval of living cells into microfluidic devices and their
manipulation thereafter. Automated continuous individual cell transfer is
a critical step in single-cell applications using microfluidic devices. Cells
must be aspirated gently from a buffer before transferring to an operation
zone to avoid artificially perturbing their biostructures. Vision-based
manipulation is a key sensing technique that allows nondestructive
cell detection. In this chapter, we present a design for an automated single-cell transfer module that can be integrated with complex microfluidic
applications that examine or process one cell at a time such as the current
nuclear transplantation method. The aim of the system is to automatically transfer mammalian fibroblasts (~15 μm) or oocytes (~100 μm) one
by one from a container to a polydimethylsiloxane (PDMS) microchannel
and then transport them to other modules. The system consists of two
main parts: a single-cell suction module and a disposable PDMS-based
microfluidic chip controlled by external pumps. The desired number of
vacuumed cells can be directed into the microfluidic chip and stored in
a docking area. From the batch, they can be moved to the next module
by activating pneumatic pressure valves located on two sides of the chip.
The entire mechanism is combined with monitoring systems that perform the detection/tracking and control program.
7.1 Introduction
Microfluidic technology and its applications are extensive and have many
significant advantages, bringing the benefits of miniaturization, integration, and automation to biotechnology-related studies over the past several
decades (Jager, Inganäs, and LundstrÖm 2000; Vilkner, Janasek, and Manz
2004). Microfluidic-based technology offers a convenient platform for cellular analyses of biological systems, because the small scale of microchannels and devices allows producing scalable system architectures (Unger et
al. 2000; Walker, Zeringu, and Beebe 2004). Their inexpensive composition
makes them a potential candidate for large-scale production. Microfluidic
technology covers not only the material phenomena but also the technology
for manipulating and controlling the components as microsize particles in
microsize artificial capillaries. Therefore, the integration of these technologies with microrobotic applications could be useful in the automation of cell
manipulation for important areas such as single-cell analysis, manipulation,
and treatment, including nuclear transplantation (Cui et al. 2001; Lee et al.
2003; Ramesham and Ghaffarian 2000; Schwarz and Hauser 2001).
Integration of cell treatment steps is crucial to developing microfluidic
devices for analysis of cell constituents, cell lysis, and cell culture (Elfwing
et al. 2004; Schonholzer et al. 2002). For example, experimental results
show that microfluidic technology provides a significant advantage in the