The effect of aluminum ions and sorbitol on collagen and skin: A thermally stimulated current spectroscopy study

Abstract

The influence of aluminum ions introduced either directly or with sorbitol, in collagen and skin, has been investigated by Thermally Stimulated Current/TSC spectroscopy. The intramolecular mobility of collagen has been found to be significantly reduced by aluminum ions. The substitution of water molecules by aluminum ions on intramolecular hydrophilic sites is suggested to be responsible for this evolution. The presence of sorbitol minimizes this effect. The intermolecular mobility of collagen is decreased upon introduction of aluminum ions in presence of sorbitol. This result can be explained by the interaction of sorbitol-aluminum entities with the telopeptidic regions of collagen molecules. In skin samples, the intra- and intermolecular mobilities are restored due to the combined actions of sorbitol and noncollagenous proteins and other macromolecules.

ALS-like skin changes in mice on a chronic low-Ca/Mg high-Al diet

“…The interaction of collagen with Al ions was reported by NMR [29], which induced conformational changes in these molecules. The intramolecular mobility of collagen was significantly reduced by Al ions, probably through a substitution of water molecules by Al ions on intramolecular hydrophilic sites [26]. The collagen diameter is related to the specific interactions between proteoglycans and collagen fibrils [28].…”

“…Metal ions and divalent cations are involved in the collagen metabolism. Heavy metal ions are capable of inducing cross-linking between peptide chains of collagen, and improve the capacity of collagen to resist denaturation as well as the attack by enzymes, bacteria and chemical agents [26]. Ca 2 + and Mg 2 + regulated the integrindependent adhesion and de-adhesion of dermal fibroblasts and epidermal kerationcytes to various extracellular matrix proteins [27].…”

Reinforcement of collagen with covalently-functionalized single-walled carbon nanotube crosslinkers

“…13 Other chemical crosslinking methods using polyvalent cations, such as trivalent chromium 15,16 and aluminium, 17 have been used successfully to produce ionic crosslinks; however, these methods significantly interfere with the mobility of collagen in biomedical applications. 18 Other methods have involved reagents that covalently crosslink collagen to form a hydrogel matrix. Aldehydes, such as † Electronic supplementary information (ESI) available: Thermogravimetric analysis of the collagen hydrogels to determine the SWNT content within the collagen matrix; differential scanning calorimetry of collagen hydrogels crosslinked by PEI or PEI-SWNTs to examine the changes caused by crosslinking collagen; experimental details regarding general procedure for determination of primary amine content using a ninhydrin assay; syntheis of dimethyoxy poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (M108); preparation of M108-stabilized SWNT solution; exact recipes for different collagen preparations.…”

Pluronics as crosslinking agents for collagen: novel amphiphilic hydrogels

“…While these physical crosslinking methods are straightforward, they commonly yield insufficient degrees of crosslinking 13. Other chemical crosslinking methods using polyvalent cations, such as trivalent chromium15, 16 and aluminium,17 have been used successfully to produce ionic crosslinks; however, they have not been successful in biomedical applications 18…”