Home | This Week's Contents  |  C&EN ClassifiedsSearch C&EN Online

Millennium Special Report
C&EN 75th Anniversary Issue
Related Stories
Let's Get Small
[C&EN, April 2, 2001]

Downsizing Chemistry
[C&EN, Feb. 22, 1999]

[C&EN Archieve]

Related People
Osaka University
E-mail this article to a friend
Print this article
E-mail the editor
ACS Seeks A Society Secretary

American Chemical Society Secretary Halley A. Merrell has announced his plans to retire at the end of this year. The society has opened a search to replace him. The position is advertised in this week's C&EN Classified section on page 80. (Applications must be received by Sept. 20). Merrell has been with ACS for 38 years; he became ACS secretary in 1998.

The society secretary is the secretary of the board of directors and the council and is the main liaison with the board and various governance units.

 Table of Contents
 C&EN Classifieds
 News of the Week
 Cover Story
 Editor's Page
 Government & Policy
  Government & Policy
 ACS News
 Digital Briefs
 ACS Comments
 Career & Employment
 Special Reports
 What's That Stuff?
 Pharmaceutical Century

 Hot Articles
 Safety  Letters

 Back Issues

 How to Subscribe
 Subscription Changes
 About C&EN
 Copyright Permission
 E-mail webmaster
August 20, 2001
Volume 79, Number 34
CENEAR 79 34 p. 14
ISSN 0009-2347
[Previous Story] [Next Story]

Working Microdevices Edge Closer To Reality


"Fantastic Voyage"--the film in which a miniaturized Raquel Welch and her colleagues venture through a patient's bloodstream in a tiny submarine--no longer seems so fantastical. Recent news reports have described a camera-containing pill that photographs the digestive tract. And Japanese researchers have now made microdevices that could proceed through the body "through even the smallest blood vessels, for example, to deliver clinical treatments" [Nature, 412, 697 (2001)].

Applied physics professor Satoshi Kawata and coworkers at Osaka University have crafted what they say are the smallest model animals and among the smallest functional micromechanical systems ever made. Their "micro-bulls" are 10 µm long and 7 µm high, about the size of a red blood cell. Their similarly sized "micro-oscillator system" consists of a bead fastened to a spring attached to a cubic anchor. The scientists employ laser-trapping force to catch hold of the bead and pull on it. When released, the bead moves as the spring contracts and relaxes.

The Japanese team uses "two-photon photopolymerization" to create the 3-D structures. An infrared laser is beamed into a liquid urethane-acrylate resin containing photoinitiators, and the resin solidifies wherever two photons are simultaneously absorbed. Movement of the laser's focal point location is managed by computer. After the pattern is completed, unreacted resin is washed away. The researchers bettered the technique's previous minimum feature size of 600 nm by controlling laser-pulse energy and exposure time to give a resolution of 120 nm.

DOWNSIZED The fine features of the bull and the functionality of the ball-on-a-spring device demonstrate the laser technique's capabilities.

Chemical & Engineering News
Copyright © 2001 American Chemical Society

Home | Table of Contents | News of the Week | Cover Story
Business | Government & Policy | Science/Technology
Chemical & Engineering News
Copyright © 2001 American Chemical Society - All Right Reserved
1155 16th Street NW • Washington DC 20036 • (202) 872-4600 • (800) 227-5558

CASChemPortChemCenterPubs Page