Abstract
Square-wave voltammetry of solid naphtho- quinone, anthraquinone, and flavone dyes, carmine, co- chineal red, indigo, and Prussian blue, was compared to microanalysis (sample consumption <1 mg) of tradi- tional painting pigments and dyes without their pre- liminary dissolution. Electrochemical analysis was also performed after the samples' hydrolysis simultaneously with thin-layer chromatography. Anthraquinone-based pigments and Prussian blue are reversibly reduced, co- chineal red and lac dyes are irreversibly reduced, flavones are mostly reversibly oxidized, dragon's blood is irre- versibly oxidized and reduced, and indigo yields both reversible oxidation and reduction. The potential window of these reactions is about 1.4 V wide. This variability permits identification of the kind of pigment or dye, and directly distinguishes, for example, alizarin and purpurin; luteolin and quercetin; or indigo and Prussian blue.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
