NMR analysis for tiny samples

Using a refined version of nuclear magnetic resonance technology, or NMR, scientists have unlocked secrets hidden in tiny amounts of venom taken from harmless spindly insects. The study of the toxin from these insects, called common two-stripe walking sticks, could help in the search for natural substances to make medicines.

The analytical technique was devised by scientists at the McKnight Brain Institute of the University of Florida and the Center for Medical, Agricultural and Veterinary Entomology at the Gainesville US Department of Agriculture. It also shows that scientists can obtain volumes of information from very tiny samples, which could be useful in efforts to understand Alzheimer’s disease and other disorders.

Researchers at the McKnight Brain Institute’s Advanced Magnetic Resonance Imaging and Spectroscopy equipped a standard NMR spectrometer with an extremely sensitive probe to examine the venom.

Developed by scientists at the National High Magnetic Field Laboratory at UF and in Tallahassee, and a manufacturer of NMR equipment, the probe is only about 5cm in diameter, and the space for the sample itself is about 1 millimetre in diameter.

When in use, the probe is cooled to lower than 400 degrees Fahrenheit below zero to reduce electrical signals that would interfere with the analysis. But the sample area itself is kept warm to protect the specimen.

They discovered compounds in the samples not previously known to be present in these animals, as well as chemical differences in secretions from the same walking stick at different times. Notably, they found a high concentration of glucose, a simple sugar and vital cellular fuel.