What are the most critical steps in the library generation?
First Strand cDNA Synthesis:
Do not cool the mastermix containing E1 (step 3).
Have the RNA / Custom Targeted Primer or RNA / FS/ DTT / dT samples at 42 – 50 °C when adding the E1-containing mastermix (step 4) to avoid mishybridization.
Mix properly by pipetting.
Do not forget to shortly spin down the samples at room temperature before and after adding the E1-containing mastermix.