Buffer RPE is a essential for removing contaminants during Qiagen RNeasy RNA purification. Its correct use—particularly the addition of absolute ethanol, two full wash volumes, and a complete dry spin—directly impacts RNA purity and downstream application success.
Buffer RPE generally contains alcohol and may contain mild irritants. Standard laboratory personal protective equipment (PPE), including gloves and safety glasses, should be worn. Waste disposal should follow local regulations for organic solvent and chemical waste. buffer rpe qiagen
: According to its Safety Data Sheet (SDS) , Buffer RPE is not classified as a hazardous substance or mixture. Usage in Standard Protocols Buffer RPE is a essential for removing contaminants
After final RPE wash, a is essential to remove residual ethanol, which otherwise inhibits downstream applications (RT-PCR, sequencing). Usage in Standard Protocols After final RPE wash,
| Step | Function | Mechanism | |------|----------|------------| | | Remove chaotropic salts (e.g., guanidine thiocyanate) | Ethanol precipitates RNA; salt contaminants dissolve into ethanol/Tris buffer | | Second wash (RPE) | Remove residual ethanol-soluble inhibitors (e.g., phenol, proteins) | Further purification; low-ionic strength buffer prevents RNA elution prematurely |
The purification process involves three distinct phases where Buffer RPE acts in the second phase (Washing):
Commercial Buffer RPE is typically supplied as a concentrate. For laboratory use, it must be diluted with 96–100% ethanol before use. Failure to add the correct volume of ethanol results in a wash buffer with insufficient alcohol concentration, leading to the premature elution of nucleic acids and significantly reduced yields. Conversely, ensuring the correct ethanol concentration is critical for maintaining the precipitation state of the DNA/RNA.