TY - JOUR
T1 - Labeling nanoparticles: Dye leakage and altered cellular uptake
AU - Snipstad, S.
AU - Hak, S.
AU - Baghirov, H.
AU - Sulheim, E.
AU - Mørch, Ý.
AU - Lélu, S.
AU - von Haartman, E.
AU - Bäck, M.
AU - Nilsson, K.P.R.
AU - Klymchenko, A.S.
AU - de Lange Davies, C.
AU - Åslund, A.K.O.
PY - 2017
Y1 - 2017
N2 - In vitro and in vivo behavior of nanoparticles (NPs) is often studied by tracing the NPs with fluorescent dyes. This requires stable incorporation of dyes within the NPs, as dye leakage may give a wrong interpretation of NP biodistribution, cellular uptake, and intracellular distribution. Furthermore, NP labeling with trace amounts of dye should not alter NP properties such as interactions with cells or tissues. To allow for versatile NP studies with a variety of fluorescence-based assays, labeling of NPs with different dyes is desirable. Hence, when new dyes are introduced, simple and fast screening methods to assess labeling stability and NP-cell interactions are needed. For this purpose, we have used a previously described generic flow cytometry assay; incubation of cells with NPs at 4 and 37°C. Cell-NP interaction is confirmed by cellular fluorescence after 37°C incubation, and NP-dye retention is confirmed when no cellular fluorescence is detected at 4°C. Three different NP-platforms labeled with six different dyes were screened, and a great variability in dye retention was observed. Surprisingly, incorporation of trace amounts of certain dyes was found to reduce or even inhibit NP uptake. This work highlights the importance of thoroughly evaluating every dye-NP combination before pursuing NP-based applications.
AB - In vitro and in vivo behavior of nanoparticles (NPs) is often studied by tracing the NPs with fluorescent dyes. This requires stable incorporation of dyes within the NPs, as dye leakage may give a wrong interpretation of NP biodistribution, cellular uptake, and intracellular distribution. Furthermore, NP labeling with trace amounts of dye should not alter NP properties such as interactions with cells or tissues. To allow for versatile NP studies with a variety of fluorescence-based assays, labeling of NPs with different dyes is desirable. Hence, when new dyes are introduced, simple and fast screening methods to assess labeling stability and NP-cell interactions are needed. For this purpose, we have used a previously described generic flow cytometry assay; incubation of cells with NPs at 4 and 37°C. Cell-NP interaction is confirmed by cellular fluorescence after 37°C incubation, and NP-dye retention is confirmed when no cellular fluorescence is detected at 4°C. Three different NP-platforms labeled with six different dyes were screened, and a great variability in dye retention was observed. Surprisingly, incorporation of trace amounts of certain dyes was found to reduce or even inhibit NP uptake. This work highlights the importance of thoroughly evaluating every dye-NP combination before pursuing NP-based applications.
KW - Drug delivery
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-84963800614&partnerID=MN8TOARS
U2 - 10.1002/cyto.a.22853
DO - 10.1002/cyto.a.22853
M3 - Article
SN - 1552-4922
VL - 91
SP - 760
EP - 766
JO - Cytometry Part A
JF - Cytometry Part A
IS - 8
ER -