Metal Binding Peptides for Separation and Concentration in Hydrometallurgy

Abstract

Strong solid binding peptides selected through biopanning methods sometimes show precipitating activity in solutions containing specific inorganic precursors. Material specificity of these peptides could offer selective precipitation as an alternative method in metal extraction and separation. While a majority of peptide guided biomineralization studies focus on improving molecular assembly and synthesis of nanoscale materials, few have considered the potential for selectively precipitating metals and compounds from complex solutions. The goal of this work is to explore relevant literature and investigate precipitation activity of two metal binding peptides l-AuBP1 and l-AgBP1 for Au and Ag particles in the absence of reducing agents. In triplicate UV-Vis studies at room temperature, l-AuBP1 triggered formation of solid Au, but not Ag particles while l-AgBP1 formed neither. Furthermore, oxidation of l-AuBP1, confirmed through mass spectrometry, indicates molecular degradation limiting its potential use in biomining applications.