How to deal with low yield of RNA & DNA co-prepared library?

√ If the sample is a co-extracted total nucleic acid, quantification of RNA and DNA should be performed separately using Qubit, and library amplification should be carried out according to the recommended cycles in the manual. 

√ During the experiment, RNase-free consumables must be used, and the operating environment should be free of RNase contamination, as this can affect the efficiency of RNA reverse transcription.

√ If the nucleic acid sample contains excessive amounts of chelating agents, guanidine salts, phenol, proteins, ethanol, or other impurities, it can impact the activity of RNA reverse transcriptase and the efficiency of DNA enzymatic digestion. It is recommended refer to purify the nucleic acid samples using 2X NadPrep SP Beads, replace the elution reagent with Nuclease Free Water, and then proceed with library preparation.

√ For samples of lower quality, consider increasing the number of PCR amplification cycles appropriately.