Microfluidic Production of Pyrophosphate Catalyzed by Mineral Membranes with Steep pH Gradients. Issue 18 (27th February 2019)

• Record Type: Journal Article
• Authors: Wang, Qingpu; Barge, Laura M.; Steinbock, Oliver
• Is Part Of: Chemistry. Volume 25:Issue 18(2019)
• Page Start: 4732
• Page End: 4739
• Publication Date: 2019-02-27
• Subjects: catalysis -- microfluidics -- origins of life -- prebiotic chemistry -- pyrophosphate; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201805950
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: Pyrophosphate might have functioned as an energy storage/currency molecule on early Earth, essential for the emergence of life. Here we synthesized mineral membranes involving iron(II), iron(III), and other divalent metal cations (calcium, manganese, cobalt, copper, zinc, and nickel) and tested their ability to catalyze the formation of pyrophosphate from phosphate and acetyl phosphate across steep pH gradients in microfluidic devices. We studied the chemical compositions of the precipitate membranes (which included vivianite, goethite, and green rust) using in situ and ex situ micro‐Raman spectroscopy. The yields of pyrophosphate were determined by aqueous 31 P NMR spectroscopy. We found that Fe 2+ and Ca 2+ were the best catalysts for pyrophosphate synthesis among investigated ions; Fe 3+ and mixed‐valence iron membranes were also able to promote pyrophosphate formation. In addition, the pH gradients across the membranes affected the pyrophosphate yields and the smallest pH gradient resulted in the highest yield. These results suggest a possible route of substrate phosphorylation in prebiotic hydrothermal systems. Abstract : Mineral membranes, formed in microfluidic devices at the reactive interface between laminar streams of reactant solution, catalyze the production of pyrophosphate from phosphate and acetyl phosphate. The steep pH gradients across the membranes mimic alkaline hydrothermal vent conditions and were found to strongly affect pyrophosphate yields.