1. Culture cells in their complete medium (growth medium with 10% FBS). Dissociate the cells with trypsin and wash with PBS once.

2. Incubate 0.2 million cells with fluorescently labeled RNA nanoparticles at a final concentration of 50 nM to 100 nM in their growth medium, at 37 °C for 1 to 2 hrs.

3. Wash cells with PBS, re-suspend cells in 200-300 ul of PBS buffer.

4. Assay the binding of RNA nanoparticles with cells by Flow Cytometry, decide excitation and mission spectrum based on the information from your product.

Reference:
1. Shu Y, Shu D, Haque F, Guo P. Fabrication of pRNA Nanoparticles to Deliver Therapeutic RNAs and Bioactive Compounds into Tumor Cells. Nature Protocols 2013;8:1635-1659. 

2. Shu D, Li H, Shu Y, Xiong G, Carson WE, Haque F, Xu R, Guo P. Systemic Delivery of Anti-miRNA for Suppression of Triple Negative Breast Cancer Utilizing RNA Nanotechnology. ACS Nano 2015; 9:9731-9740. 

3. Shu D, Shu Y, Haque F, Abdelmawla S, Guo P. Thermodynamically stable RNA three-way junction for constructing multifunctional nanoparticles for delivery of therapeutics. Nature Nanotechnology 2011; 6:658-67.