Fig. 2From: Penetration of CdSe/ZnS quantum dots into differentiated vs undifferentiated Caco-2 cellsFluorescence stability of QDs. Fluorescence intensity of QD-COOH and QD-NH2 dispersed in cell culture medium was measured for up to 7 days. Excitation wavelength was 380 nm. Emission was measured at 655 nmBack to article page