Fig. 4

Stable incorporation of P800SO3-PEG into the bone matrix. a Blood curve and pharmacokinetic parameters obtained from CD-1 mice retro-orbitally injected with 25 nmol of P800SO3-PEG. b Longitudinal biodistribution of P800SO3-PEG fluorophores in nude mice. 50 nmol (2.5 mg kg⁻¹) of P800SO3-PEG was injected intravenously to 20 g athymic NCr nu/nu mice and imaged for 14 d post-injection. Scale bars = 1 cm. SBR was calculated as the fluorescence intensity of each spine divided by the signal intensity of the neighboring skin as a background (n = 3, mean ± S.D). c Long-term signal integrity of P800SO3-PEG. 50 nmol of P800SO3-PEG was injected intravenously to 20 g CD-1 mice 1 d or 14 d prior to imaging (n = 3, mean ± S.D). Scale bars = 4 mm. d H&E and NIR imaging of resected bone tissues taken from mice 1 d and 14 d post-injection (c). Scale bars = 50 µm