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Biologically Inspired Robotics
and fluorescent microscopy (Cookson et al. 2005), which are other popular
microfluidic methods that require manipulation of living cells one at a time.
To the best of our knowledge, there exists no successfully implemented nondestructive automated single-cell loading and supply system.
Our motivation in this study is to support on-chip cloning technology.
Gentle cell handling and supply into a microfluidic chip one by one is the first
part of a successful application, because any damage to the cells could cause
experimental failure. The cells must be aspirated precisely from a container,
which requires micromanipulation and accurate positioning while approaching the target cell with a glass micropipette (suction tip) attached to a micromanipulator. Secondly, the desired number of cells is stored in a dock. The
snake-shaped PDMS docking zone is designed for this purpose. Once cells
are sorted, they are transferred to the next module or operation zone. To do
this, a “Y” character microchannel is combined with the docking side and the
pneumatic pressure valves are formed at the intersection of the two. When
the external pump infuses air into the valves, the membrane between the
layers deflects, closing the fluidic flow. Finally, synchronization of the valves
and the suction tip are handled via monitoring systems, which provide full
automation and system integration. Because the intersection of PDMS chip
is monitored by a compact vision system, the suction tip is monitored by a
microscopic system. Instead of using two microscopic units, which requires
a long tube connection between the suction tip and the microfluidic chip, we
designed the compact vision system as a nondestructive sensing method in
order to enable high-throughput single-cell transfer.
This chapter is divided into three main sections according to the different
parts and functions of the systems: (1) materials and methods, (2) experimental results, and (3) discussion and conclusion. In the first section, the materials used to fabricate the microfluidic chip and methods for preparing cells
as well as a new design of a compact vision structure are briefly described.
Secondly, an automated cell detection/tracking and controlling algorithm is
presented along with its applications in microfluidic chips, micromanipulators, and pumps. In the final section, experimental results indicating the
efficiency and usability of the total mechanism are described.
7.2 Materials and Methods
The proposed system is able to singly pick cells from a container and transport
them to a microfluidic chip. The structure allows manipulating cells in microfluidic channels and docking them in desired locations in controllable numbers. However, due to the complex physical properties of oocyte and donor
cells, manipulating cells through a microfluidic chip poses certain challenges.
Biologically Inspired Robotics
and fluorescent microscopy (Cookson et al. 2005), which are other popular
microfluidic methods that require manipulation of living cells one at a time.
To the best of our knowledge, there exists no successfully implemented nondestructive automated single-cell loading and supply system.
Our motivation in this study is to support on-chip cloning technology.
Gentle cell handling and supply into a microfluidic chip one by one is the first
part of a successful application, because any damage to the cells could cause
experimental failure. The cells must be aspirated precisely from a container,
which requires micromanipulation and accurate positioning while approaching the target cell with a glass micropipette (suction tip) attached to a micromanipulator. Secondly, the desired number of cells is stored in a dock. The
snake-shaped PDMS docking zone is designed for this purpose. Once cells
are sorted, they are transferred to the next module or operation zone. To do
this, a “Y” character microchannel is combined with the docking side and the
pneumatic pressure valves are formed at the intersection of the two. When
the external pump infuses air into the valves, the membrane between the
layers deflects, closing the fluidic flow. Finally, synchronization of the valves
and the suction tip are handled via monitoring systems, which provide full
automation and system integration. Because the intersection of PDMS chip
is monitored by a compact vision system, the suction tip is monitored by a
microscopic system. Instead of using two microscopic units, which requires
a long tube connection between the suction tip and the microfluidic chip, we
designed the compact vision system as a nondestructive sensing method in
order to enable high-throughput single-cell transfer.
This chapter is divided into three main sections according to the different
parts and functions of the systems: (1) materials and methods, (2) experimental results, and (3) discussion and conclusion. In the first section, the materials used to fabricate the microfluidic chip and methods for preparing cells
as well as a new design of a compact vision structure are briefly described.
Secondly, an automated cell detection/tracking and controlling algorithm is
presented along with its applications in microfluidic chips, micromanipulators, and pumps. In the final section, experimental results indicating the
efficiency and usability of the total mechanism are described.
7.2 Materials and Methods
The proposed system is able to singly pick cells from a container and transport
them to a microfluidic chip. The structure allows manipulating cells in microfluidic channels and docking them in desired locations in controllable numbers. However, due to the complex physical properties of oocyte and donor
cells, manipulating cells through a microfluidic chip poses certain challenges.