2,2,6,6-Tetramethyl-4-amino [d₁₇]piperidine-¹⁵n-l-oxyl as a spin label for cell surface carbohydrates.

The first use of perdeuterated, ¹⁵N-Tempamine spin label to selectively monitor cell surface sialic acid of human erythrocyte membranes is reported. The molecular reasons for significantly increased sensitivity and significantly decreased scatter in the data over that of protonated, ¹⁴N-Tempamine are discussed. These advantages are illustrated by monitoring the effects of wheat-germ agglutinin on the motion of terminal sialic acid of membrane glycoconjugates.