Figure 2

(A) Monitoring of saphenous vein signals after tail vein injections of 20-kDa PEG–IRDye800 conjugate (P20D800) or 40-kDa PEG–IRDye800 conjugate (P40D800) (25 μl of 40 μM each). n = 4 mice each tracer. (B) Schematic showing stepwise tail vein infusion setup to determine sensitivity of detection in blood of P40D800 tracer. (C) Plot showing saphenous vein signal enhancement during stepwise infusions of 10 μl of 1 μM P40D800. Representative of n = 3 independent experiments. (D) Plot showing saphenous vein signal during stepwise infusions of 10 μl of 0.1 μM P40D800. Representative of n = 4 independent experiments. Detection threshold indicates time point where signal increase is first detected after 3 infusions of 0.1 μM P40D800.