Figure 2. NIR-images after intra-articular injection of (a) IR-780 dye alone, (b) NIR-HA, (c) NIR-M, or (d) HA/NIR-M into articular knee joints of RA animals (Scale bars = 50 mm), and (e) release time versus signal-to-background ratio (SBR) determined at each time point (a–d).