In this 21st Century Chemist profile, Purdue University analytical chemist Mary Wirth works with "nanomaterials" to improve the clarity and accuracy of tests for tiny "biomarker" proteins that indicate disease -- specifically, levels of PSAs, or Prostate Specific Antigens, that signal prostate cancer.

An FDA panel will weigh whether there is enough evidence of a connection between food dyes and hyperactive behavior in some children to either ban food dyes, or require manufacturers to put warning labels on products that use them.

Image array showing comparative size and diameters of several items -- DNA, a raindrop, a strand of hair, a house, an ant and the Indianapolis Motor Speedway, as measured in nanometers, micrometers, millimeters, meters and kilometers. Source: Lawrence Berkeley Laboratory, US Dept of Energy, National Center for Electron Microscopy

Pie chart showing breakdown of $1.8 billion in proposed federal funding for nanoscience, from research into processes to nanomaterials to nanomanufacturing. Source: National Science and Technology Council, 2011

This 2010 "Scientific American" article reports on identification of a possible genetic marker for an aggressive prostate cancer; prostate cancer is the second most common cancer in men after skin cancer. A new market could improve screening tests. Source: Scientific American, January 11, 2010

A sampling of purple shades of paint, with commercial names; from the offerings of U.S. paint company Benjamin Moore. Source: Benjamin Moore & Co. (2010)

A report by the New York Times raises questions about the effectiveness of widespread cancer screenings.

This 2009 "Scientific American" article reports on an archaeological find, in a cave in the Republic of Georgia, of ancient flax fibers spun and dyed, dating back 32,000 years -- older than previously-known oldest evidence of textile-making 28,000 years ago. Source: Scientific American, September 10, 2009

This 2009 "Scientific American" article reports on sources of two widely-used blue food dyes: Blue No. 1, a synthetic dye derived from coal tar, and Blue No. 2, a synthetic version of indigo from plants. Some research has linked both synthetic dyes to attention deficit disorder (ADD). Source: Scientific American, January 30, 2009

Graphic illustrates estimated new cancer cases and estimated cancer deaths, by site in body or type (lung, breast, prostate) among men and women in 2007. Source: American Cancer Society (2007)

Image array of "Things Natural" and "Things Manmade" with their measurements in millimeters, micrometers or nanometers; with scale ranging from 0.1 nm to 10 mm. Source: Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy

Thousands of hippies descend on a Detroit park for a "love-in," a recent social phenomenon that's sweeping the country.

This NBC Learn video, part of a series on "Chance Discoveries" in chemistry, tells the story of the discovery of the first synthetic dye, mauvine (or mauve) in 1856, by a teenaged British chemist trying to make a synthetic quinine to treat malaria in the expanding British colonies. (Images Courtesy of BASF Coorporate Archives, Science Museum London/SSPL, Williams Haynes Portrait Collections, from the collections of the Chemical Heritage Foundation; Gift of Herb Pratt, From the collections of the Chemical Heritage Foundation; Photograph by Gregory Tobias, Gift of American Cyanamid, from the collections of the Chemical Heritage Foundation; Dr. Morley Read / Photo Researchers, Inc.)