Researchers from Israel suggest that bubbles might have played an important role in the formation of basic organic chemicals, adding a new hypothesis to how the building blocks of life came to be.
The study, published in ACS Central Science, used a computer simulation to understand the effects of collapsing bubbles on different gasses rich in carbon and nitrogen. As a bubble collapses on itself, due to changes in the liquid, conditions inside can experience pressures and temperatures high enough to start chemical reactions.
The different scenarios show that depending on the type of gas you put in the bubbles, it is possible to form a large array of complex organic substances. The team made 12 models, with different configurations of methane, carbon monoxide, and carbon dioxide with the like of nitrogen, hydrogen cyanide, or ammonia. As the bubble collapses, the different mixes create transient “shocked” molecules that settle into eight specific ones as they cool down.
Once cooled, they begin to interact with the environment. This made them even more interesting. The molecules can easily become lipids, sugars, amino acids, and even nucleic acids – the bases of DNA and RNA. The model shows that methane bubbles were the most efficient way to produce amino acids.
The collapsing bubble theory, technically known as sonochemical synthesis, could be included in other widely discussed ideas. Bubbles are found in many places, from the ocean floor and volcanic vents to waterfalls and geysers. This might be an important contribution to the complex debate of just how life came to be on Earth.
While the model shows that biologically relevant molecules can be created in these bubbles, sonochemical synthesis remains exclusively theoretical. To be a serious contender among different theories, the researchers will have to produce experimental results that backup their simulated scenarios.
There is so much we don’t know about the formation of life on Earth. At some point almost 4 billion years ago, certain molecules became “alive”, but the path to that transition and the transition itself is unclear.
There is no certainty for the formation of life. Molecules might have been brought to Earth by a comet or an asteroid, after forming in the depth of space, or they might be the results of volcanism and other geological effects.
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