Penetration of CdSe/ZnS quantum dots into differentiated vs undifferentiated Caco-2 cells

Table 1 Physico-chemical properties of QDs used in the study

Sample	Hydrodynamic diameter [nm]			Height (TEM) [nm]	Zeta potential [mV]
	Water	DPBS	MEM+	Height (TEM) [nm]	Water	DPBS	MEM+
QD-COOH	17 ± 4 (21 %)	19 ± 4 (22 %)	10 ± 4 (37 %)^a	13 ± 1	−39 ± 3	−36 ± 2	−8 ± 3
QD-NH₂	ND	ND	34 ± 18 (53 %)	13 ± 1	−36 ± 1	−2 ± 0	−3 ± 1
QD-PEG	ND	38 ± 10 (25 %)	11 ± 4 (41 %)^a	14 ± 1	−25 ± 0	0 ± 2	−3 ± 1

^a Pure cell culture medium (MEM+) without QDs was measured as a reference and hydrodynamic diameters of 7 ± 2 nm were obtained representing the size of BSA, which is the most abundant protein in MEM+.The measured values therefore rather represent the hydrodynamic diameter of the proteins in the medium

ISSN: 1477-3155