Study of bovine pericardium biochemical and biomechanical properties during collagenase degradation using fluorescence lifetime imaging (Conference Presentation)

Bovine pericardium (BP) exhibits distinct biochemical and biomechanical properties that are dominant by the structural protein collagen. The enzymatic degradation of collagen molecules is critical for in vivo incorporation and remodeling of BP in tissue engineering applications. A non-destructive method for monitoring BP during degradation would provide a valuable tool for quantifying functional changes initially in vitro and ultimately in vivo. In this study, we demonstrated the sensitivity of multi-spectral fluorescence lifetime imaging system (ms-FLIm) developed by our group to collagen content and compressive modulus of BP during collagenase degradation. A pairwise study was performed using bacterial collagenase to partially digest BP. We measured the biomaterials properties with ms-FLIm and destructive conventional measurements including collagen assay, compressive test and histology. A single factor study design was utilized. Test group samples were digested by bacterial collagenase for 0, 8, 16 and 24 hours, while control group samples were prepared in the Hank’s balanced salt solution to control for time in solution. Statistical analysis was performed using the Kendall τB correlation test. The results demonstrate that fluorescence parameters measured by ms-FLIm are significantly correlated with collagen content and compressive modulus (|τB| > 0.45, p < 0.05). Based on these findings, we aim to predict BP’s collagen content and mechanical properties using fluorescence metrics, and ultimately apply ms-FLIm for non-destructively monitoring of in vivo remodeling of BP.