title: Chemometric study of Maya Blue from the voltammetry of microparticles approach.
abstract: The use of the voltammetry of microparticles at paraffin-impregnated graphite electrodes allows for the characterization of different types of Maya Blue (MB) used in wall paintings from different archaeological sites of Campeche and YucatAn (Mexico). Using voltammetric signals for electron-transfer processes involving palygorskite-associated indigo and quinone functionalities generated by scratching the graphite surface, voltammograms provide information on the composition and texture of MB samples. Application of hierarchical cluster analysis and other chemometric methods allows us to characterize samples from different archaeological sites and to distinguish between samples proceeding from different chronological periods. Comparison between microscopic, spectroscopic, and electrochemical examination of genuine MB samples and synthetic specimens indicated that the preparation procedure of the pigment evolved in time via successive steps anticipating modern synthetic procedures, namely, hybrid organic-inorganic synthesis, temperature control of chemical reactivity, and template-like synthesis.
authors.affiliation: Departament de Química Analítica, Universitat de València, Dr. Moliner, 50, 46100 Burjassot, València, Spain. antonio.domenech@uv.es
authors.forename: Antonio
authors.initials: A
authors.lastname: Doménech
authors.forename: María Teresa
authors.initials: MT
authors.lastname: Doménech-Carbó
authors.forename: María Luisa Vazquez
authors.initials: ML
authors.lastname: de Agredos Pascual
mesh_terms: D001106:Archaeology; D004563:Electrochemistry; D004566:Electrodes; D006108:Graphite / Q000737:chemistry; D007203:Indigo Carmine; D007211:Indoles / Q000737:chemistry*; D008800:Mexico; D046529:Microscopy, Electron, Transmission / Q000379:methods; D015394:Molecular Structure; D053758:Nanoparticles / Q000737:chemistry*; D010151:Paintings; D010316:Particle Size; D010860:Pigments, Biological / Q000737:chemistry*; D012680:Sensitivity and Specificity
chemical_list: D007211:Indoles; D010860:Pigments, Biological; D006108:Graphite; D007203:Indigo Carmine