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Further, the ideal experiment does not involve any human intervention.A reaction or a reaction network is allowed to unfold, and the sample is only broken up when the experiment has been finished.Perhaps, samples are drawn, as in the famous Miller experiment, but there is no addition of new chemicals or an artificial change in conditions.This type of single-run experiment has worked well for simple processes, such as the formation of sugars in a formose reaction.When Diego Maradona was asked about having used his hand to score a goal in the quarter-finals of the 1986 soccer World Cup, he initially claimed that there had been divine intervention, and the term “Hand of God Goal” was coined.—There had been manual intervention, and there had been an understandable interest of the player not to admit it.—Organic chemists, if not all experimentalists in the field of prebiotic chemistry, are faced with a similar dilemma.We do our best to perform experiments that we believe re-enact possible steps of prebiotic evolution, but we know that we need to intervene manually to obtain meaningful results.For example, an elimination reaction needs other conditions than an addition reaction, and assuming that both will occur simultaneously in the same solution is unrealistic.
Often, if a reagent has already been found somewhere in the geosphere, it is considered plausible, and if it was taken from the catalog of a chemical supplier, it is not. Further, how likely it is that a series of transformations occurred that require vastly different conditions in a specific sequence, is not easy to gauge, even for the specialist.
Experimentalists in the field of prebiotic chemistry strive to re-enact what may have happened when life arose from inanimate material.
How often human intervention was needed to obtain a specific result in their studies is worth reporting.
Each enzyme creates a specific microenvironment for a reaction in its active site.
For potentially prebiotic, enzyme-free multistep syntheses, a chemical work-up at the end of a reaction is often required, involving steps such as precipitation, crystallization or other forms of handling and purification, and an often drastic change in chemical conditions from one synthetic transformation to the next.