Cationic lipid transfection (CAT#: STEM-GT-0003-WXH)

Cationic lipid-based reagents spontaneously form condensed nucleic acid-cationic lipid complexes via electrostatic interactions between the negatively charged nucleic acid and the positively charged head group of the synthetic lipid.
The positive surface charge of the liposomes mediates the interaction of the nucleic acid and the cell membrane, allowing for fusion of the liposome/nucleic acid transfection complex with the negatively charged cell membrane. The transfection complex is thought to enter the cell through endocytosis. Transfected DNA is translocated to the nucleus to be expressed, while RNA or antisense oligonucleotides skip the translocation step and remain in the cytoplasm. Cationic lipids are thought to facilitate DNA transfection during the early steps of the process by mediating DNA condensation and DNA/cellular interactions.

1. Dilute RNA, siRNA, or oligonucleotides and the transfection reagent in separate tubes.
2. Combine nucleic acid and transfection reagent to form complexes.
3. Add nucleic-transfection reagent complexes to cells. Positive charge on cationic lipid helps bind complex to membrane.
4. Assay transfected cells for gene expression or silencing.