Iron‐Silicate Chemical Garden Morphology and Silicate Reactivity with Alpha‐Keto Acids

Abstract

Chemical gardens, which are self‐organizing, abiotic, inorganic precipitates in far‐from‐equilibrium systems, are of interest for prebiotic chemistry/origin of life research and, under certain reaction systems, can be considered hydrothermal vent analogs. While the presence of different additives to chemical gardens, including phosphate and amino acids, have been explored, the reactivity of organic molecules in chemical garden systems is not well understood. Here we explored the reactivity of two metabolically important alpha‐keto acids (pyruvic acid and glyoxylic acid) and ammonia in the presence of iron‐silicate chemical gardens. While reactivity was not observed in the case of pyruvic acid, we found that glyoxylic acid formed alpha‐hydroxy acids and amino acids. We found that the observed organic reactivity can be attributed to the silicate in the exterior solution as opposed to the solid iron‐containing chemical garden structure. These results have implications for the reactivity of hydrothermal vent chimneys and their surrounding environments in iron‐ and silica‐rich systems.

Downward fingering accompanies upward tube growth in a chemical garden grown in a vertical confined geometry

“…Classical experiments of 3D gardens grown from a seed are still carried out by many scholars and have produced a lot of important results. [68][69][70][71][72] Typically, the procedure involves placing a seed crystal of metal salt at the bottom of the vessel and filling it with solution. Thereafter, precipitation occurs around the seed and forms a semi-permeable membrane, and we will then observe tubular filaments just like the upward-growing tubes reported in this paper.…”

Characteristic growth of chemical gardens from mixtures of two salts

“…[1][2][3][4][5] For the past four centuries, numerous studies of these fascinating precipitation patterns have been reported. These studies focused on various physicochemical factors [6][7][8][9][10][11][12][13][14][15] including oscillatory growth of hollow microtubes, 12 tube growth with a pinned bubble, 14 and spiral growth of the tube controlled by the application of magnetic force. 15 Recently, chemical gardens have received attention as biomimetic materials due to their ability to form a variety of self-assembled structures, [16][17][18][19][20][21][22][23][24][25][26][27] such as silica-rich biomimetic mineral 20 and self-assembled nanostructures.…”