Adapter titration in TruSeq stranded mRNA sample preparation

[chicken]

Hi,
I am doing transcriptome analysis and prepared some RNA libraries from total RNA. Allways using 500ng of total RNA. I always got the problem that I got a lot of adapter dimers in the end. I check it by loading sample on an agarose gel. I suspect that I somehow have to titarate the adapter but I do not know how since there are no suggestions in the prepration guide and I do not know the concetration of the adapter-mix is. Have anybody done a titration before with that certain preparation kit?? I would be really happy about a little hint.

Thanks in advance.

Used Kit: TruSeq stranded mRNA sample preparation by Illumina

[NGSeqer]

Hi Chicken,

The AMPure bead cleanup after adapter ligation should remove most adapter dimer. Things that can affect bead cleans up are: using incorrect bead to sample ratio, expired beads, and not using freshly made EtOH.