New and Emerging Technologies from Skeletal Muscle Tissue Engineering: Insect Muscle Bioactuators for Robotic Applications.
Bioactuation involves using biological components, such as muscle cells, to generate
mechanical force. The applications for this technology include microelectromechanical
systems (MEMS), actuators in small robots, and moving parts in any meso-scaled device.
The advantages of fabricating an actuator from cells, rather than synthetic materials,
are their ability to self-assemble, be ... read morepowered by natural fuel sources such as sugar and
fat, operate silently over fast time scales, and biodegrade. Several studies have
investigated the feasibility of forming bioactuators from mammalian muscle, but their
stringent environmental requirements limit their applicability to real-world devices.
Therefore, we have investigated the use of insect cells toward a bioactuation system;
insect tissues are known to tolerate a wide range of temperature, pH and starvation
conditions. Manduca sexta cells were isolated from embryos staged for the presence of
myoblasts and, using insect hormone 20-hydroxyecdysone, differentiated into functional
muscle fibers. The cultures display cross-striations, are multinucleated, and survive
for periods of > 3 months without medium replenishment. We investigated the potential
cause for this and found that maternally-derived yolk cells were also present in our
cultures. In the embryo, these cells are responsible for the storage, breakdown and
delivery of carbohydrates, amino acids, and lipids to the developing embryo. We
hypothesized that this process could also be taking place in our cultures. We have
further developed these cells into scaffold-free 3-dimensional tissues, grown at high
density in PDMS chambers. Over periods of one week, the cells condense into contractile
structures; the presence of a mixture of cell types contributes to the ability of the
tissue to maintain its integrity without the need for an extracellular matrix or gel
support. The muscle tissues produce forces in the uN range spontaneously, which is
comparable to literature results for mammalian engineered tissues stimulated
electrically. Additionally, we have shown that these tissues are capable of exerting
force onto synthetic supports for robotic displacement. The results of our studies have
demonstrated that robotic and microsystem actuation may be achieved using contractile
insect muscle tissues generated in vitro.
Thesis (Ph.D.)--Tufts University, 2013.
Submitted to the Dept. of Biomedical Engineering.
Advisor: David Kaplan.
Committee: Barry Trimmer, Lauren Black, and George Christ.
Keywords: Biomedical engineering, Biology, and Robotics.read less