Bioanalyzer results after IVT, bead purification, aRNA fragmentation and another bead purification: a) The aRNA has the correct size distribution of 300 – 700 nt but the adapter peak is extremely high (>600 FU), which can inhibit the library preparation. Extra rounds of aRNA bead purifications are recommended. b) The aRNA has the correct size distribution but the yield is low (<4 FU), possibly due to loss during bead purification. c) The aRNA has an increased size distribution of 500 – 2,000 nt indicating that fragmentation was not complete. In addition, the yield is low (<2.5 FU) indicating loss during bead purification. d) The aRNA has the correct size distribution and good yield (>20 FU) and can be used for library preparation.