
A Close-Up Look at Cotton Fibers By Jill Lee May 21, 1997Its been 5,000 years since cotton
fiber was first woven in the Indus Valley in what is now Pakistan, so you might
think researchers in this era of DNA fingerprinting and genetic engineering
would have long since seen everything cotton has to show. But an atomic force microscope has made it possible for scientists with
USDAs Agricultural Research Service to
see cotton fibers magnified 170,000 times their actual size. This gave the
scientists their first three-dimensional look at the cellulose chains that make
up cottons fiber. These chains, called microfibrils, are so small that it
takes nearly 1,000 of these strands to make a single cotton fiber. Working with scientists at the University of
Southwestern Louisiana, the ARSresearchers were able to obtain high-resolution images of the cottons
primary and secondary cell walls, as well as pictures of the microfibrils. This
will help these researchers to fully explore how a fibers structure
dictates its strength and other properties. The new view of cotton could yield important secrets, such as how enzymes
interact with cotton. Enzymes are gaining favor with detergent manufacturers
and textile producers because they can remove stains and keep fabric looking
smooth. But some enzymes can cause fiber wear and interfere with the
cloths dyeability. The atomic force microscope could benefit future breeding efforts because it
lets researchers pinpoint subtle distinctions between good versus outstanding
cotton fiber. Another plus: With the AFM, fiber samples can be studied in their
natural state and dont have to be coated, stained or otherwise altered.
These pre-treatments can mask or destroy some surface characteristics of the
samples. Scientific contact: Barbara Triplett, ARS
Southern Regional
Research Center, New Orleans, La., phone (504) 286-4275,
[email protected];
Thomas C.
Pesacreta, University of Southwestern Louisiana, Lafayette, La., phone
(318) 482-5233, [email protected] Story contacts Barbara A Triplett U.S. Department of Agriculture | |