LASRA's pioneering work on collagen provides better understanding of leather
Using a fluorescence detector on the HPLC, LASRA researchers have a precision tool to determine the amino acid composition of biological materials to a very high degree of resolution. Photo: LASRA.
LASRA leather researchers have developed a novel method to quantify ‘collagen crosslinks’ using mass spectrometry and have established a super-sensitive method for amino acid analysis. They have found that collagen crosslinks have a strong correlation to skin and leather strength and that amino acids are excellent indicators for the monitoring and optimisation of established leather processing protocols.
Proteins are large biomolecules that consists of one or more long chains of amino acids found in different forms to achieve specific functions. Collagen is the most abundant protein in mammals making up 35% of the total whole-body protein. It is mostly found in connective tissues (tendons, ligaments, cartilage, and skin), making up 90 % of the skin structure.
Collagen itself is a triple-helical structured protein that consists primarily of glycine, proline, and hydroxyproline, and its structure is stabilised by different naturally-occurring crosslinking agents. The types and amount of crosslinking agent found in skin changes with age, significantly affecting the biomechanical properties of the skin matrix.
“We are the only research institute in the world that can quantify the nine collagen and elastin crosslinks in skin and leather without the need for derivatisation or the use of an ion-pairing agent for separation. These nine crosslinks are lysinonorleucine (LNL), hydroxylysinonorleucine (HLNL), dihydroxylysinonorleucine (DHLNL), histidinohydroxylysinonorleucine (HHL), pyridinoline (PYR), deoxypyridinoline (DPYR) desmosine (DES), isodesmosine (IDS) and histidinohydroxymerodesmosine (HHMD). Using a fluorescence detector on the HPLC, we have a precision tool to determine the amino acid composition of biological materials to a very high degree of resolution. Our technique provides a full separation of all the standard amino acids, including the two amino acids unique to collagen (hydroxyproline and hydroxylysine) as well as proteoglycans, elastin and keratin,” says LASRA’s Director, Geoff Holmes.
These methods have enabled LASRA researchers to quantify the removal of both amino acids and crosslinks in hides and skins during the different leather processing stages including soaking, liming and bating and even post-tanning. Currently, LASRA is working closely with industry to quantify their leather processing regimes to enable them to modify their processing methods to achieve improvements in leather quality.
LASRA’s collagen and biomaterials research group has recently begun work on a new MBIE-funded research project investigating across a number of interdisciplinary research areas in collaboration with their national and international partners, including the generation of novel collagen constructs.
For more information about LASRA please see: https://www.lasra.co.nz/
Date posted: 19 March 2018