Interference pigment

GC requires low molecular weight molecules, and the macromolecular nature of proteinaceous materials (made up of 21 amino acids covalently condensed) means that they are typically too large to be readily identifiable and time consuming pretreatments of the sample are required. In order to free the amino acids, hydrolysis is required. Subsequent steps of purification to eliminate pigment interferences are also often necessary. Consequently sample pretreatments must be carefully carried out to reduce the risk of loss and/or contamination of the sample. 

G. Gautier, M.P. Colomhini, GC MS Identification of Proteins in Wall Painting Samples A Fast Clean up Procedure to Remove Copper based Pigment Interferences, Talanta, 73,95 102 (2007). 

A third way to avoid pigment interference is to use a biological oxidizer. This specialized apparatus burns samples (dried onto pieces of filter paper) and collects the 3H and 14C directly into separate scintillation cocktails as water and CO2, respectively. 

Nonmetallic inorganic materials are widely used for optical purposes lenses, pigments, interference filters, laser hosts, luminescent coatings, displays, solar cells, fiber optics, lamp bulbs, and tubes. For optical applications use is made of the refractory index, light absorption, luminescence, and nonlinear optical behavior of materials. These are intrinsic but may depend on the concentration of impurities. Refraction index and optical absorptivity in insulators are atomic properties and are only indirectly related to the structure, but the structure affects the selection rules and the term splitting in the atomic chromophores. The coordination number determines the intensity and wavelength of absorption and... 

Gautier, G, Colombini, M.P. (2007) GC-MS identification of proteins in wall painting samples a fast clean-up procedure to remove copper-based pigment interferences. Talanta, 73,95-102. 

Pigmentation interferes somewhat with tenacity but, with reasonably low amounts of pigment, good physical properties of the fibers are attainable. 

Gisslen L, Scholz R (2009) Crystallochromy of perylene pigments interference between Frenkel excitons and charge-transfer states. Phys Rev B 80 23... 

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