German Scioptric Ball Microscope (circa 1700s)

License Info
Image Use
Custom Photos
Site Info
Contact Us

The Galleries:

Photo Gallery
Silicon Zoo
Chip Shots
DNA Gallery
Amino Acids
Religion Collection
Cocktail Collection
Screen Savers
Win Wallpaper
Mac Wallpaper
Movie Gallery

Spike (M.I.) Walker

Vitamin C Quilt Patterns

English photomicrographer Spike (M.I.) Walker has been a consistent winner of the Nikon Small World competition for many years and has published many articles and a book about microscopy. Featured below is a photomicrograph of Vitamin C (cyan and red squares) recrystallized in a shape reminiscent of a quilt-like pattern.

Vitamin C Quilt Patterns

One of Spike Walker's most notable accomplishments in the field of polarized light microscopy is his ability to control the crystallization of vitamin C from evaporated aqueous solutions. The photomicrograph presented above is from a supersaturated solution placed on a microscope slide that was scratched into approximately 1.5-millimeter squares with a fine needle to provide 'windows' in which crystallization could proceed independently. The preparation was breathed on at 60-second intervals to alter the rate of crystal growth fronts. Illumination was provided by a 12-volt, 100-watt tungsten halide lamp with crossed polarizers. The microscope was a Zeiss Ultraphot III equipped with an automatic 35-millimeter photohead. The film was Fujichrome Velvia. (10x)

Ascorbic acid, also known by the chemical name L-ascorbic acid, is a water-soluble vitamin that functions as a powerful antioxidant. Although most animals can synthesize vitamin C, others -- such as humans, other primates, and guinea pigs -- obtain it only through their diets. Vitamin C is commonly found naturally in peppers, citrus fruits, tomatoes, melons, broccoli, and green leafy vegetables such as spinach, turnip, and mustard greens.

Vitamin C is known to be essential in a variety of metabolic functions, but the details of its mechanism aren't yet understood. It is necessary for synthesis of collagen (a protein important in the formation of healthy skin, tendons, bones, and supportive tissues and in wound healing); maintenance of the structural strength of the blood vessels; metabolism of certain amino acids; and the synthesis or release of hormones in the adrenal glands. Although some anecdotal evidence suggests that vitamin C plays a part in protecting the body against infection, that claim has not been scientifically proven yet.

Chemically, L-ascorbic acid occurs as a white or slightly yellow crystal or powder with a slight acidic taste and darkens on exposure to air and light. As a dry state, it is reasonably stable in air, but it rapidly oxidizes in solution. Ascorbic acid is freely soluble in water; sparingly soluble in alcohol; insoluble in chloroform, ether, and benzene.


Questions or comments? Send us an email.
Text and graphics for this article are
© 2000-2019 by Spike (M. I.) Walker.
All Rights Reserved under copyright law.
© 1995-2019 by Michael W. Davidson and The Florida State University. All Rights Reserved. No images, graphics, software, scripts, or applets may be reproduced or used in any manner without permission from the copyright holders. Use of this website means you agree to all of the Legal Terms and Conditions set forth by the owners.
This website is maintained by our
Graphics & Web Programming Team
in collaboration with Optical Microscopy at the
National High Magnetic Field Laboratory.
Last modification: Friday, Nov 13, 2015 at 01:18 PM
Access Count Since November 18, 2000: 10528
Microscopes provided by:
Visit the Nikon website. Visit the Olympus Microscopy Resource Center website.