In 1912, the biologist Sergei Stepanovich Chakhotin (1883 – 1973) introduced an instrument for manipulating larger microorganisms, tissues, and small animals. It provided a means of attaching a microtool directly to the head of the microscope.
Chakhotin—”Tschachotin” is the German transliteration—developed this instrument while working at the Parasitology Department of the Institute for Experimental Cancer Research in Heidelberg, Germany, which had been founded in 1906 by the surgeon Vincenz Czerny (1842-1916).
Chakhotin’s instrument, which clamped directly to the tube of a microscope, was meant for operating on larger cells (amphibian eggs, for instance) as well as small organisms. The instrument would accept a variety of tool tips, from electrodes to glass needles. The tool tip was lowered into the specimen by means of a rack and pinion mechanism (T). The tip could then be manipulated using the mechanical stage holding the vessel containing the specimen. The illustration above shows the instrument used with a specialized container that Chakhtin had developed for his 1908 doctoral investigation of the statocyst of Pterotrachea at Heidelberg University.
The instrument was made according to Chakhotin’s instructions by an instrument maker (Präzisionsmechaniker) named Fr.[anz?] Runne who was located in the town of Rohrbach near Heidelberg. [Tshachotin 1912a, 188] Chakhotin does not seem to have had any commercial interest in its production or development—any information about its adoption by other researchers would be appreciated. Its operating principle is similar to other technologies which attached a tool directly to the head of the microscope, such as that introduced in 1922 by Jeppe Ørskov, a Danish bacteriologist, for producing single cell colonies.
The microsurgury device was Chakhotin’s second significant technological contribution. He had earlier introduced a method of ultraviolet micropuncture to selectively damage living cells using focused ultraviolet radiation. [Tshachotin 1912b] Chakhotin is perhaps best known for his work as a German Social Democrat and antifascist who opposed the Nazi movement during the interwar period.