Hans Fischer Biography

Hans Fischer was a medically-minded chemist who won the Nobel Prize for chemistry for his pioneering investigations into the chemical structure of pyrroles, molecular compounds which give the specific color to many important biological substances, including blood, bile, and the leaves of plants. Building on the foundations laid by his predecessors and colleagues, many of them from Fischer's homeland of Germany, he spearheaded a series of investigations lasting more than two decades that led to the synthesis of hemoglobin, bilirubin, and (more than 25 years after his death) chlorophyll. During the course of his investigations, Fischer developed and oversaw an extremely productive microanalytical approach to studying chemical compounds, especially the pigments that occur in nature. By overseeing specific laboratory procedures conducted simultaneously by several labs, Fischer was able to conduct more than 60,000 microanalyses of chemical substances. In 1930, he won the Nobel Prize, primarily for his work in elucidating the structure of and synthesizing the blood pigment hemin.

Fischer was born at Höchst am Main in Germany on July 27, 1881, to Eugen Fischer, a dye chemist, and Anna Herdegen Fischer. Through his father's work as laboratory director at the Kalle Dye works, Fischer developed an early interest in the chemical nature of pigments, or coloring matter. Interested in both chemistry and medicine, Fischer received his doctorate in chemistry in 1904 from the University of Marburgh and his M.D. in 1908 from the University of Munich. After working on chemical structure of peptides and sugars with Emil Fischer (no relation) in Berlin, Fischer went to the Physiological Institute in Munich, where he first began his study (under Freidrich von Müller) of pigments, an area that was to become the overriding focus of his scientific pursuits. Fischer's dual expertise in chemistry and medicine led him to become chair of medical chemistry at the University of Innsbruch in 1916. Although he published his first notable scientific paper (on the subject of bilirubin, or bile pigment) in 1915, his research efforts soon came to a standstill due to World War I and the following years of reconstruction after Germany's defeat. Fischer's ill health also impeded his research efforts. He contracted tuberculosis when he was 20 years of age and had a kidney removed in 1917 due to complications from the disease.

Lays Groundwork for Nobel Prize-winning Discovery

In 1921, Fischer's investigation of pigments began in earnest as he accepted an appointment as director of the Institute für Anoreganische Chemise at the Technische Hochschule, or Technical University, in Munich. It was there that Fischer would conduct his groundbreaking research into pyrrole chemistry for nearly a quarter of a century. Fischer immediately reinitiated his studies of bile pigments and organized a number of specialized laboratories to simultaneously conduct the specific tasks needed to determine their chemical structures. Using a process known as Gattermann aldehyde synthesis to systematically prepare the numerous compounds needed for pyrrole derivatives, Fischer organized teams of microanalysts, sometimes referred to as "Gattermann cooks." He also set up specific laboratories to work on individual segments of a chemical problem, such as making calorimetric determinations and developing X-ray diagrams. By segmenting the work, Fischer's laboratory turned out more new chemical compounds than any laboratory that had preceded it.

Fischer's first major advance was the discovery of porphyrin synthesis in 1926. Porphyrins are made up of pyrroles joined in a chemical ring and are the pigments that appear throughout nature. The accepted view in chemistry prior to Fischer's work was that a single basic porphyrin structure was the primary component for all pigments occurring in nature. Fischer began to unravel the fundamental chemical structure of the porphin (the nucleic core of porphyrins), which had been proposed by W. Küster in 1912. This accomplishment led to the discovery of specific molecular structures of individual porphyrin groups that make up certain pigments. Specifically, Fischer had found that porphyrins are made up of four pyrrole nuclei bound by methane groups into a ring structure. This led to the creation of porphyrin in a laboratory setting. With the ability to synthesize porphyrin, Fischer and his colleagues were able to further determine thousands of specific porphyrin structures. In Great Chemists, Heinrich Wieland, an organic chemist, describes Fischer's attempt to synthesize porphyrins. "Fischer began to put the pyrrole segments together in mosaiclike arrangements and then to weld together, by brilliant synthetic procedures, the semimolecules of the pyrrometheenes produced in this manner." Fischer soon recognized that porphyrins differed primarily through the components that made up the rings. He also discovered that bilirubin was derived from hemin and identified it as a porphyrin.

In 1929, Fischer successfully synthesized hemin, showing that its ring had a center atom of iron. Fischer received the Nobel Prize in chemistry in 1930 for his synthesis of hemin, which is one of two components of hemoglobin, the red respiratory protein of erythrocytes (red blood cells or corpuscles). During the Nobel Prize ceremonies, Fischer was also noted for his demonstration that hemin is related to chlorophyll, the light absorbing, green plant pigment. In 1944, Fischer finally worked out the chemical structure of and synthesized the pigment bilirubin, which he had first begun investigating during World War I. Over the years, Fischer's laboratory had synthesized approximately 130 porphyrins. He also conducted in-depth studies of the specific structure of chlorophyll and published 129 papers on the topic. He successfully identified chlorophyll's pyrrole rings, which had a center of magnesium rather than iron like hemin's pyrrole rings. The synthesis of chlorophyll, while based largely on Fischer's work, was not accomplished until 1960, 15 years after his death.

Obsession with Work Leads to Suicide

Fischer was a dedicated scientist who had few outside interests. He was also secretive and seldom discussed his work with other scientists outside of his laboratory. Fischer's lack of outside interests extended to politics as well. Although he privately expressed concern over the rise of dictator Adolf Hitler and Nazi Germany, he chose not to speak out publicly. In 1935, Fischer married Wiltrud Haufe. Despite being three decades older than his bride, Fischer was a happily married man and once confided to Wieland, who was a personal friend, that his wife had greatly enriched his life.

Despite Fischer's dedication to his work, which some colleagues called obsessive, he did enjoy taking long motoring vacations in his car. His other love was the outdoors. Although he constantly battled the debilitating effects of tuberculosis, Fischer was an expert skier, accomplished hiker, and an avid mountain climber, a passion he shared with his father until an accident claimed the elder Fischer's life. Germany's involvement in World War II added to Fischer's woes. Because of supply restrictions and frequent bombing raids made by Allied forces, his work was seriously restricted. When a bombing run destroyed Fischer's institute, the scientist gave in to despair. In 1945, Fischer committed suicide, despondent over what he viewed as the destruction of his life's work.

Although he was able to organize large scientific efforts and had an intuitive feel for the chemical structures involved in the field of pyrrole chemistry, Fischer was not noted for his ability to clearly write or lecture on such topics. Despite this fact, he published the definitive work on pyrrole chemistry in three volumes, Die Chemie des Pyrrols, which has remained a standard text on the subject. In addition to the Nobel Prize, Fischer received the Leibig Memorial Medal in 1929 and the Davy Medal in 1936. He also received an honorary degree from Harvard University in 1935.