Hello Sachanandani,

You can use DMSO to dissolve the SLNs with and without Quercetin to evaluate its cytotoxicity using MTT assay. DMSO can easily dissolve the lipid-coated capsules.

Wish you good luck!

Dear Jagruti!

You also read this article:

Article Effects of Quercetin-Loaded Nanoparticles on MCF-7 Human Bre...

1. Preparation of QT-SLNs

The SLNs of QT were prepared using Compritol (as lipid, Gattefossé, Saint-Priest, France) and Tween 80 (as a surfactant) through a microemulsification technique [35,36]. Briefly, Compritol was heated to 70–75 °C, and 50 mg of QT (Sigma-Aldrich, St. Louis, MO, USA) was added to the molten lipid. Six mL of water and Tween 80 were mixed separately and heated to 70–75 °C. Then, the two solutions were mixed and stirred to produce a clear homogenous microemulsion. The homogenized microemulsion was added to the 100 mL of cold water and stirred (40 min) to get a fine dispersion of the SLNs. The QT-SLNs suspension was stored at 4 °C. Different formulations of QT-SLNs based on lipid-drug ratios were prepared (Table 1).

2.6. Cell Viability

MTT assay was used to compare the effect of QT-SLNs with QT on cell viability. Briefly, MCF-7 and MCF-10A cells (1 × 104 cells/well) were cultured in 96-well plates. After treatment, the MTT solution at a concentration of 0.5 mg/mL was added to each well and maintained at 37 °C for 4 h. After removing the supernatants, 100 µL of DMSO was added to each well. Using a microplate reader (BioRad, Hercules, CA, USA), absorbance at 570 nm was measured. To determine the toxic effect of QT-SLNs on the MCF-7 cells, IC50 values were measured by MTT assay, as previously described [38]. The IC50 values were calculated using SigmaPlot software.

I agree with Debasish Kumar Dey