Micro-Spherical Heart Pump Powered by Cardiomyocytes Yo Tanaka1, Kae Sato1, Tatsuya Shimizu2, Masayuki Yamato2, Teruo Okano2, Takehiko Kitamori1 1The University of Tokyo, Bunkyo, Tokyo, 113-8656, Japan 2Tokyo Women’s Medical University, Shinjuku, Tokyo, 162-8666, Japan Ref: μTAS2006 報告者: 9633584 黃紫郁

Outline Introduction Materials and Methods Results and Discussion Other Micro-Pump This Group’s Micro-Pump Materials and Methods Results and Discussion Conclusions References

Introduction: Other Micro-Pump Electric Power Electric Powerless (Zengerle, et al. ,1995 IEEE) Jungyul Park, et al. , 2007 Lab Chip (J.H. Tsai, L. Lin, 2001 IEEE) (C. Cabuz, S.T. Lu , 2001 IEEE)

Introduction: This Group’s Micro-Pump Lab Chip, 2006, 6, 362–368 Lab Chip, 2007, 7, 207–212 Medium

Materials and Methods A hole (600 μm in diameter) in the center of sugar ball and edible silver was detached. Teflon capillary (200 μm in inside and 400 μm in outside diameters) was threaded through the hole and molten glucose by using a hotplate at 150 ℃ was applied around the hole.

Materials and Methods About 1 mL of PDMS prepolymer solidified at 100 ℃ for 1 hour above a hotplate under rotation (22 rpm). Drawing and insertion of capillaries, and the two capillaries were attached to sphere using epoxy glue.

Materials and Methods One capillary was connected to a syringe pump and dissolving sugar ball in water. A hollow sphere (about 5 mm in diameter, 250 μm in thickness) with connected capillaries was fabricated. The PDMS sphere was sterilized and immersed for 1 h in 50 μg mL-1 fibronectin solution in PBS at 37 ℃ to promote cardiomyocyte attachment.

Results and Discussion A cultured cardiomyocyte sheet produced periodic contractile-expansion motion of the PDMS micro spherical heart. Spherical polystyrene tracking particles (1 μm diameter) were dispersed in cell culture medium within the capillaries.

Results and Discussion Before transplantation After transplantation

Conclusions New fabrication methods to create a novel micro spherical heart-like pump prototype. Regular fluid motion in a capillary connected to the hollow pumping sphere, with the device working continuously over 5 days. This device is a fully integrated, wireless mechanochemical converter, driven with only chemical energy input from culture milieu. ，

Conclusions External control of both fluid motion and mechanical performance of the bio-actuator is possible using culture temperature. Possible applications: as an electric powerless bio-actuator to drive fluids in implanted micro-chemical or biochemical medical implant devices. as a component of a cardiovascular circulatory system micro- model to study mechanisms of circulatory physiology, pathology, and developmental biology.

References Y. Tanaka, K. Morishima, T. Shimizu, A. Kikuchi, M. Yamato, T. Okano, T. Kitamori, Lab Chip, 6, 362-368, (2006). Y. Tanaka, K. Sato, T. Shimizu, M. Yamato, T. Okano and T. Kitamori, Lab Chip, 2007, 7, 207–212. Y. Tanaka, K. Sato, T. Shimizu, M. Yamato, T. Okano, Ichiro Manabe, Ryozo Nagai and T. Kitamori, Lab Chip, 2008, 8, 58-61. Jungyul Park, Il Chaek Kim, Jeongeun Baek, Misun Cha, Jinseok Kim, Sukho Park, Junghoon Lee and Byungkyu Kime, Lab Chip, 2007, 7, 1367–1370