Figure 4. Uptake study by flow cytometry.

Conjugation of folate on to nanoparticle increases its uptake in Y79 (a). A suspension of curcumin and Cur-NPs, Fol-Cur-NPs (10 µg/ml) was incubated with folate receptor expressing Y79 and non-expressing A549 cells (100,000 cells) for 2 hrs, and uptake of NPs by the cells were determined with flowcytometer by measuring the mean fluorescence intensity value. Competitive inhibition of uptake of Fol-Cur-NPs by addition of free folate (b). Y79 cells were treated with 0–30 mM of free folate for 1 h prior to incubation with curcumin and Cur-NPs, Fol-Cur-NPs and then subjected to above protocol. Mean fluorescence intensity of curcumin fluorescence in the cells was measured (n = 3; mean±s.e.m, (*) p<0.05 drug in solution versus drug loaded NPs, (**) p<0.005 drug in solution versus Fol-Cur-NPs).