Mice received an i.v. injection of saline or PLGA-b-HA particles encapsulating AF647-conjugated BSA (Dose: 16 mg/kg). At 2 h post injection, various organs were quickly dissected and imaged using IVIS. All images were taken with an excitation wavelength of 640 nm and an emission wavelength of 680 nm. (A) Representative ex vivo fluorescence images of the organs of 3–5-month-old wild-type mice receiving saline (n = 3 mice), 5-month-old young C57BL/6J mice receiving fluorescent PLGA-b-HA particles (n = 3 mice), 3–4-month-old young APP/PS1 mice receiving fluorescent PLGA-b-HA particles (n = 3 mice), 15–17-month-old APP/PS1 mice receiving fluorescent PLGA-b-HA particles (n = 3 mice), and 15–17-month-old non-carrier (NC) control littermates receiving fluorescent PLGA-b-HA particles (n = 3 mice). (B) Quantification of particle fluorescent intensity per unit area in brain and other organs. Data represents the mean ± SEM. One-way ANOVA with Tukey Post Hoc test results are shown (*p<0.05; ***p<0.001).