Adsorption of l-aspartate to rutile (α-TiO2): Experimental and theoretical surface complexation studies

Mineral Surfaces, Geochemical Complexities, and the Origins of Life

“…The work of Jonsson et al (2009Jonsson et al ( , 2010, who studied the adsorption of L-glutamate and L-aspartate on the surface of rutile (a-TiO 2 , pH PZC ¼ 5.4) in NaCl solutions using potentiometric titrations and batch adsorption experiments over a wide range of pH, ligandto-solid ratio, and ionic strength, illustrates the need for such integrated studies. Not only did they find that adsorption depends strongly on ionic strength and glutamate concentration, but the extended triple-layer surface complexation model of all the experimental results also indicated the existence of at least two surface glutamate complexes.…”

Catalytic peptide hydrolysis by mineral surface: Implications for prebiotic chemistry

“…Chang (1988) surveyed the potential of mineral surfaces to adsorb dilute monomers, and concluded that it was unlikely that this was the case. However, there are also more recent experiments that suggest that some amino acids are adsorbed very strongly to some mineral surfaces, especially under appropriate conditions of pH and ionic strength Jonsson et al, 2009Jonsson et al, , 2010Hazen and Sverjensky, 2010). Understanding the possible contributions of mineral surfaces to peptide oligomerization is thus central to several models for the origin of life (Orgel, 1998;Zaia, 2004).…”

“…Glycine is also one of the most chemically stable a-amino acids (Abelson, 1959;Vallentyne, 1964;Hare and Mitterer, 1969;Andersson and Holm, 2000;Snider and Wolfenden, 2000;Li and Brill, 2003a,b) and therefore the conclusions reached may be true of many amino acids . However, it is also clear that some amino acids, for example those with multiple negative or positive charges, such as aspartic and glutamic acids and lysine may form innersphere complexes with oppositely charged mineral surface sites mediated via their ionizable side chains Jonsson et al, 2009Jonsson et al, , 2010, which may be bound considerably more strongly than those formed by simple zwitterions like glycine. There may thus be significant differences between peptides composed of more complex charged amino acids and oligoglycines.…”

Stochastic Prebiotic Chemistry within Realistic Geological Systems

“…More recently, a series of studies by Hazen and collaborators have addressed the issue of chemistry at geological interfaces, proposing that crystal surfaces of Hadean eon-relevant minerals provide an effective substrate upon which the concentration of prebiotic molecules could have been achieved [17][18][19][20][21][22][23][24] . These works have demonstrated the pivotal role played by mineralwater interfaces in both concentration and catalysis processes.…”