Gilbert Ning Ling (December 26, 1919 – November 10, 2019) was a Chinese-born American cell physiologist, biochemist and scientific investigator.

In 1947 he co-developed the Gerard-Graham-Ling microelectrode, a device that allows scientists to more accurately measure the electrical potentials of living cells.

In 1948 he completed his Ph.D on the effects of metabolism, temperature and other factors on the membrane potential of single frog muscle fibers which was published in December 1949 in a series of 4 papers in the Journal of Cellular and Comparative Physiology, Volume 34, Issue 3.

In 1944, Ling won the only biology slot of the sixth nationwide Boxer Indemnity Fellowship, to study physiology in the United States, which he took up in January 1946.

[citation needed] John Eccles applied the microelectrode to studies of activity of individual units within the spinal cord and brain and Andrew Huxley used it in muscle cells.

In 1963, Hodgkin with Huxley, won the Nobel Prize in Physiology or Medicine for their work on the basis of nerve "action potentials," the electrical impulses which enable the activity of an organism to be coordinated by a central nervous system.

[21] Worldwide use of this new microelectrode spread rapidly after this[22] and has subsequently proven to be one of the most important devices applied to the study of cellular physiology.

In 1974, Lawrence G. Palmer and Jagdish Gulati tested one aspect of Ling's theories; namely, whether potassium ions within the cell are bound or free.

Contrary to Ling's prediction, they found that in fact potassium ions within frog skeletal muscle cells are free.