Correcting Isobaric Peptide Mass Shifts in Proteomic Fiber Quantification
Correcting isobaric peptide mass shifts in proteomic fibre testing prevents false wool detections and protects cashmere customs declarations from penalties.
Intermediate Filament Keratins
Fiber Architecture
Structural proteins forming the primary mechanical scaffold within animal hair fibers determine the physical properties of wool and specialty hairs. These intermediate filament keratins are organized into long, alpha helical chains that provide elasticity and strength. They reside within the cortical cells of the fiber.
Hydrogen bonds and disulfide bridges hold these structures together to resist deformation.
Thermal Stability
Resistance to heat and environmental degradation stems from the tightly coiled nature of the protein chains. While the matrix surrounding them might soften, the intermediate filament keratins maintain the core integrity of the yarn. This stability allows wool to undergo scouring and dyeing without losing its shape.
Chemical Vulnerability
Exposure to strong alkalis or reducing agents can break the cross links within the protein structure. When intermediate filament keratins are damaged, the fiber becomes brittle and loses its natural crimp. Careful pH control during wet processing protects these structural components.
Species Identification
Variations in the amino acid sequence of these proteins allow for the differentiation between sheep wool and cashmere. Scientists use proteomic analysis to examine the specific intermediate filament keratins present in a blended textile. This verification prevents the fraudulent labeling of luxury fibers in the global market.
The ratio of different keratin types acts as a biological barcode for the origin of the material. Even after aggressive processing, these protein signatures remain detectable in the finished garment.