Biomaterials

Biography

Biography: Giuseppe Tronci

Abstract

The trends in diabetic occurrence and aging populations impose a heavy economic burden on healthcare providers worldwide [1]. Diabetic wounds suffer from delayed healing, and can soon become infected, chronic ulcers. If not treated timely, they can lead to gangrene, haemorrhage and lower-extremity amputations, potentially resulting in permanent disabilities and pain for patients. Advanced wound dressings have been commercialized to respond to the pressing needs of an increasing diabetic population. However, control of the wound microenvironment and matrix metalloproteinase (MMP) activity is still only partially accomplished, resulting in economically unaffordable healing times. Here, type I photoactive (atelo)collagen was synthesized and explored as a building block of factor-free advanced wound dressings with customisable macroscopic properties and integrated wound-regulating functionalities. Covalent functionalization of rat tail collagen with photoactive compounds, e.g. 4-vinylbenzyl chloride, was initially confirmed (by ¹H-NMR, TNBS colorimetric assay, and circular dichroism) to prompt the synthesis of UV-induced networks of collagen triple helices [2, 3]. The type and degree of collagen functionalization governed the structure-property relationships, whereby the averaged swelling ratios (SR: 707-1600 wt.%), bulk compressive (E_c: 15-129 kPa) and atomic force microscopy (AFM) elastic moduli (E_AFM: 16-387 kPa) could be adjusted [4]. Obtained network configurations proved key to control the activity of MMP-9 in vitro, with respect to a leading dressing product. This synthetic route was successfully transferred to minimally-antigenic, telopeptide-free type I collagen [5], resulting in comparable water-swollen atelocollagen networks. Preclinical investigations in a full-thickness wound model in diabetic mice proved the accelerated healing capability of this collagen system with respect to a commercial polyurethane dressing [6].