n e w s of t h e w e e k One of the key requirements for a "true nanotechnology revolution" in the information-technology hardware arena, Jasinski asserts, is coming up with a way to build billions of identical nanoscale structures cheaply and with atomic-scale precision. "Biology is very good at this," he says. "And a selfassembly method for inorganic semiconductor structures based on biological methods is very exciting." To find biomolecules with useful binding characteristics, Belcher and coworkers exposed the billion-member collection of peptides that were attached to a virus to five semiconductor surfaces. Strongly bound products were separated from the remainder of the group, amplified, and rescreened in a series of progressively more demanding binding tests. After several rounds, the few remaining candidates were analyzed using DNA sequencing and other methods. The group proposes that selective binding may be mediated by interactions between Lewis bases on the peptides and Lewis-acid sites on the semiconductor surfaces. In addition, charge polarity, atom size, and crystal structure play a role in substrate recognition, they say. In a commentary in the same issue of Nature, chemistry professor Chad A. Mirkin, Northwestern University, Evanston, 111., remarks that the UT method could be used with biomolecules that contain more than one binding site to selectively recognize and organize multiple inorganic building blocks creating structures with even greater spatial control. Mitch Jacoby
ACS Board Approves Task Force On Women In Chemistry Meeting last week at the Belmont Conference Center in Elkridge, Md., the American Chemical Society Board of Directors approved the formation of a joint Presidential-Board task force to study and make recommendations on issues related to women in the chemical professions. This action was catalyzed by board members Maureen G. Chan and E. Ann Nalley as well as the Board Committee on Professional & Member Relations (CPMR) on the ba14 JUNE 12, 2000 C&EN
sis of information gathered at the re- science, mathematics, engineering, cent National Research Council Chem- and technology education, and have ical Sciences Roundtable (CSR) con- supported legislation increasing federference on Women in the Chemical al funding of R&D. The awards will be presented at ceremonies later this Workforce. Much of the discussion at that CSR year. The board also selected Sarah E. meeting centered on the numbers and status of women in the academic sector. O'Connor as recipient of the 2000-02 Although much progress has been Irving Sigal Postdoctoral Fellowship. made in the past 50 years in terms of the O'Connor, under the direction of numbers of women completing degrees Christopher T. Walsh, will pursue in chemistry at all levels, there has been postdoctoral research at Harvard Medlittle change in the number of women ical School. The fellowship, which is who are tenured faculty at Ph.D.- administered by ACS, consists of granting institutions. CPMR stressed $35,000 per year for two years. It is that by forming the task force, the soci- named in memory of Sigal, a research ety has the opportunity to "provide chemist who, at 35, was one of the 270 strong leadership to create a brighter victims of the 1988 terrorist bombing future for women in the chemical of Pan Am flight 103 above Lockerbie, Scotland. professions." In other actions related to awards, In other business, the board selected Reps. Sherwood L. Boehlert (R- the board accepted Bruker Daltonics' N.Y.) and Vernon J. Ehlers (R-Mich.) offer to sponsor the Frank H. Field & to receive ACS Public Service Awards. Joe L. Franklin Award for Outstanding These awards honor those who have Achievement in Mass Spectrometry for made outstanding contributions to the the period 2001-05. Also announced at development of public policy that ben- the meeting was the approval by the efits chemistry and the sciences. Both Committee on Grants & Awards of 175 Boehlert and Ehlers are strong advo- Petroleum Research Fund grants-in-aid cates of the establishment and expan- totaling $6,758,973. sion of federal programs relating to Linda Raber
Gecko Bonding Whaf s behind the remarkable ability of geckos to dash up smooth vertical surfaces and even stick to a ceiling? Robert J. Full, professor of biology at the University of California, Berkeley; Kellar Autumn, assistant professor of biology at Lewis & Clark College, Portland, Ore.; and their colleagues noted that these lizards uncurl their toes like an inflating party favor when putting their feet down and peel the toes back up as if removing a piece of tape when they step away. This precise footwork may result from the fact that the adhesive force depends on how the hairs on the gecko's feet attach and detachfroma surface [Nature, 405,681 (2000)]. The foot of a Tokay gecko is cov-
Mark Moffett/ Minden Pictures
500,000finehairs, each tipped with hundreds of projections known as spatulae. Working with single hairs, the researchers found that the strongest attachment results from jamming a hair—and hence the pads on the end of the spatulae—into the surface and then pulling it slightly downward before attempting to detach it. If all the hairs on one foot were attached this way, the adhesive force would total about 100 newtons. The million hairs contained in a dime-sized spot could lift a child weighing 45 lb. The researchers believe that the adhesion is based on van der Waals interactions. The gecko's bonding capabilities maty provide the inspiration for a clean new adhesive. Sophie Wilkinson
