In 1920 A. E. Sharpenak worked under the direction of Alexei N. Bach) in the newly created Biochemical Institute.

In 1939, A. E. Sharpenak organized a biochemical department at the Moscow Stomatological Institute (MSI) (current name – Moscow State University of Medicine and Dentistry).

From 1959 to 1969, Head of the Biochemical Laboratory at the City Clinical Hospital named after S.P. Botkin (Botkin Hospital).A. E. Sharpenak died in January 1969 of complications from influenza.

Throughout the 1940s, under his leadership (V.R. Bobyleva, L.A. Gorozhankina, E.V. Aleksandrova, N.P. Dzichkovskaya, N.V. Nikolaeva, I.I. Grachev) a large amount of experimental work was carried out on the etiology of dental caries.

In 1949, after numerous experiments, Professor A.E. Sharpenak proposed the theory of dental caries due to lack of income in the organs and tissues protein, B vitamins and an excess of carbohydrates.