Analysis of diterpenoic compounds in natural resins applied as binders in museum objects by capillary electrophoresis.

The exudates of conifers consist mainly of diterpenoic acids of the abietane and pimarane type (abietic, neoabietic, dehydroabietic, palustric, pimaric, isopimaric, levopimaric and sandaracopimaric acid) and larixol acetate. These natural resins were used as adhesives, coatings, varnishes or plasticizers in artistic and historic works since ancient times. For the purpose of conservation and restoration and for art historic examination of such museum objects the identification of the binding media used is undoubtedly of paramount importance.

Animal glues in mixtures of natural binding media used in artistic and historic objects: identification by capillary zone electrophoresis.

Animal glues were often used in historic and artistic objects, e.g. as paint ground, as binders for pigments, or as adhesives.

Characterisation of natural polysaccharides (plant gums) used as binding media for artistic and historic works by capillary zone electrophoresis.

The monosaccharide constituents of plant gums were separated by capillary electrophoresis at pH 12.1 and detected with indirect UV absorbance. The plant gums investigated were gum arabic, gum acacia, gum tragacanth, cherry gum and locust bean gum (carob gum).

Characterisation and identification of proteinaceous binding media (animal glues) from their amino acid profile by capillary zone electrophoresis.

A capillary electrophoretic method for identifying different species of proteinaceous binders--collagen, egg white, and milk casein--is described. It allows characterisation of the proteins on the basis of the amino acid profiles obtained after their acidic hydrolysis. The profiles of the underivatised amino acids are recorded directly by capillary zone electrophoresis at pH 2.

Analysis of drying oils used as binding media for objects of art by capillary electrophoresis with indirect UV and conductivity detection.

Capillary electrophoresis (CE) was applied to analyse the long-chain fatty acid composition of vegetable oils, and their degradation products formed upon ageing when drying oils are used as binding media. The analytes were detected with contactless conductivity detection (CCD) and indirect UV absorption, both detectors positioned on-line at the separation capillary. The long-chain fatty acids were resolved in a background electrolyte (BGE) consisting of phosphate buffer (pH = 6.