Miller-Urey experiment organic compounds

Stanley Miller at the University of Chicago more than 50 years ago. This experiment (in fact, of course, many were carried out prior to the successful one) is probably as well known as the Wohler synthesis of urea Miller s doctoral supervisor, Harold Urey (winner of the Nobel Prize in 1934), had suggested to Miller that he simulate a reducing primeval Earth atmosphere (as required by the Oparin-Haldane hypothesis) to electrical discharges and see what happens . Urey apparently expected that such an experiment would lead to a huge variety of organic compounds. 

FIGURE 1-33 Abiotic production of biomolecules. Spark-discharge apparatus of the type used by Miller and Urey in experiments demonstrating abiotic formation of organic compounds under primitive atmospheric conditions. After subjection of the gaseous contents of the system to electrical sparks, products were collected by condensation. Biomolecules such as amino acids were among the products. 

Fig. 4.2. The Miller-Urey apparatus for abiotic synthesis of biochemicals from primordial gases is shown. Before each experiment the system was thoroughly evacuated, flushed with interstellar-type gases, and sealed. Water is brought to a boil and vapors rise through an electric discharge chamber and are re-condensed and led back into the boiling water reservoir. It took only a few weeks to produce a color change in the water which indicated an accumulation of organic compounds shown in Table 4.1. On the young earth, of course, this experiment would have been carried on for a few million years.

Figure 2.1. The Urey-Miller Experiment. An electric discharge (simulating lightning) passed through an atmosphere of CH4, NH3, H2O, and H2 leads to the generation of key organic compounds such as amino acids.

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