FIG. 2.
Fluorescence spectroscopic data acquired from the major endogenous fluorophores in the cartilage samples, including collagen type II, GAG powder, aggrecan, and NADH in cells. The time-resolved fluorescence parameters were retrieved with bi-exponential deconvolution. (a) Plots of fluorescence spectrum, (b) normalized spectrum, (c) average lifetime, (d) fast decay constant τ1 (filled symbols) and slow decay constant τ2 (open symbols) for collagen, GAG, and aggrecan (since NADH has only one exponential component, NADH was not included here), and (e) the fractional contribution of the slow decay component A2. GAG, glycosaminoglycans; NADH, the reduced form of nicotinamide adenine dinucleotide. Color images available online at www.liebertonline.com/tec