Column

Frontiers of Future MEMS Devices : “White Devices”
Shoji Takeuchi, Associate Professor, The University of Tokyo (Institute of Industrial Science)
The previous column introduced some of the future
devices being studied by the Micromachine Center. In thiscolumn, Dr. Takeuchi will provide an overview of the devices in
the field of health care and medicine.

sensors and actuators and the like are embedded in layers,
enabling the device to display data on the area inside the bodyat the location where the device is attached. The device canalso dispense medications inside the body, promote the healingof wounds and conduct other simple processes. For example,
thin ultrasonic sensor arrays might be integrated on the surfaceof the sheet, and the back of the sheet might have a flat-screen
flexible display. This would enable even a non-professional toobserve the acquired data on a large 2-dimensional display area.
Moreover, as the device is not invasive and is merely attachedto the outside of the body, it can be used to determine theblood flow and heart condition of even a healthy person,
enabling it to be used for health maintenance as well. Thedevice can also be used as a tool to allow doctors to easily
observe conditions inside the body during an operation. In
these ways, the device is expected to lead to the improvementof medical technology.

In the society of 20 years in the future, with its low
birthrate and aging population, the keyword will be “healthy till
the very end.” An environment in which everyone is able towork for a long time while continuing to maintain an
independent lifestyle will be indispensable.
However, chronic health disorders have reached epidemic
proportions. For example, there are said to be some 300 million
diabetics worldwide. It is clear that devices that can measure
blood sugar and other biological data 24 hours a day andconduct diagnosis and treatment, in such a way that theindividual is unaware that he or she is being monitored, areneeded even by healthy people. Fig. 1 shows the devices being
studied by the White Devices Working Group, which areexpected to support the health care and medical treatment
needs of people 20 years from now. A brief description of thesedevices is provided below. In addition, Table 1 shows theworking group members who conducted this study.

20 years from now, values are likely to have changed aswell. Trying to accurately predict such a future is probably
doomed from the start. Therefore, we decided to go all the way
and create a “wish-list” for the future. We were a bit hesitant at
first with regard to embedded devices, but we received support
from health care professionals who assured us that embedding
is commonplace in health care situations. So we went ahead andincluded those embedded devices to which MEMS could make acontribution. Regardless of whether or not these predictions
turn out to have been on target, they successfully reflect thedesire on the part of committee members regarding the devices
that should be built.
The future 20 years from now is a blank page, on which no
one can predict what will be written. In filling this empty white
page with our “wish list” of white device technologies, we hopeto start a dialogue about the future of medicine and health care.

(1) Ultra-miniature in vitro embedded devices
These ultra-miniature devices can be embedded in various
locations in the human body for extended periods of time.
They can reside in the abdominal cavity and digestive systemand operate autonomously to actively locate and treat tumors,
cancerous cells and so on. This will dramatically increase early
detection and cure rates. Capsule type devices that do not
require a power source may also be a possibility. These canreside in liver portals or in the veins of the arms, functioning as
the contrast medium in observations conducted from outside
the body, and they will be able to monitor blood sugar,
temperature, pressure and other data in the area around thecapsule 24 hours a day. In the case of diabetes or othercondition for which data from blood must be monitored
constantly, this type of ultra-miniature capsule will
dramatically reduce the burden on the patient.

Ultra-miniature in vitro embedded devices

Biomechanical hybrid devices

24-hour biological information
monitorUltra-high sensitivity examination and diagnosis chip(created from cells, membrane protein andother biomaterials)

Vein(2) Biomechanical hybrid devices

Bloodfloflow

These hybrid devices are created by fusing together
biomolecules, cells and so on. The use of biomaterials andfunctional high polymer materials enables these devices tosense information about the human body and the environment
with greater speed and sensitivity than conventional sensors.
As the devices are built from materials and mechanisms thatare compatible with the human body, they will be powerfultools for interfacing between the human body and machines(for example, the Brain Machine Interface or BMI). To cite one
example, a protein film or the like might be reformed on thetop of a manmade film as biomolecules with their active state
maintained, and the resulting mechanism might function as anultra-high sensitivity smell or taste sensor or otherstoichiometric sensor. Or nerve cells might be cultured on a
flexible substrate and these might be placed in contact withthe surface of the brain, enabling the cells to extend axial
fibers into the brain and connect to the desired cells. Suchcontrollable cultured cells are expected to make it possible tocreate a highly compatible and precise interface in the eventthat bioelectricity or chemical signals are detected or a
stimulus is applied.

Intravascular fixed position
continuous blood sugar measurement

Artificial organ
Brain-Machine Interface

Capsule embedded
in portal to control
blood sugar value

Sheet type health management devices

In vitro permanent self-operating
diagnostic and treatment machine

Fig. 1 Devices that will support health care and medical
technology 20 years from now
Table 1 White Device Working Group Members(in no particular order)
Shoji Takeuchi
Yoichi Haga
Satoshi Konishi
Akira Okitsu
Takafumi Suzuki
Souhei Matsumoto
Takuya Iwasaki
Tomoyasu Hasegawa
Yasuharu Hosono
Hiroyuki Fujita(3) Sheet type health monitoring devices
This device is attached to the surface of the body like apoultice to monitor the status of the patient’s health. Countless

10Institute of Industrial Science, The University of Tokyo
Biomedical Engineering Research Organization,
Tohoku University

College of Science & Technology, Ritsumeikan University
Kyoto University Hospital
Graduate School of Information Science and Technology,
The University of Tokyo
National Institute of Advanced Industrial Scienceand Technology (AIST)

Mizuho Information & Research Institute, Inc.
Olympus Corporation
Toshiba Corporation
Institute of Industrial Science, The University of Tokyo