Rate measurements of the hydrolysis of complex organic macromolecules in cold aqueous solutions: implications for prebiotic chemistry on the early Earth and Titan.
Organic macromolecules ("complex tholins") were synthesized from a 0.95 N(2)/0.05 CH(4) atmosphere in a high-voltage AC flow discharge reactor. When placed in liquid water, specific water soluble compounds in the macromolecules demonstrated Arrhenius type first order kinetics between 273 and 313 K and produced oxygenated organic species with activation energies in the range of approximately 60+/-10 kJ mol(-1). These reactions displayed half lives between 0.3 and 17 days at 273 K. Oxygen incorporation into such materials--a necessary step toward the formation of biological molecules--is therefore fast compared to processes that occur on geologic timescales, which include the freezing of impact melt pools and possible cryovolcanic sites on Saturn's organic-rich moon Titan.
Neish
C D
CD
Department of Planetary Sciences, University of Arizona, Tucson, Arizona 85721-0092, USA. cdneish@lpl.arizona.edu
Somogyi
A
A
Imanaka
H
H
Lunine
J I
JI
Smith
M A
MA
D002138:Calibration; D003080:Cold Temperature; D018534:Earth, Planet; D006868:Hydrolysis; D007700:Kinetics; D046911:Macromolecular Substances / Q000032:analysis*; D013058:Mass Spectrometry; D012015:Reference Standards; D018539:Saturn; D012996:Solutions; D014867:Water
D046911:Macromolecular Substances; D012996:Solutions; D014867:Water