Question Re:Sequence Attachment to Illumina Flow Cell

[curran]

Does anyone know how sequences are actually attached to the Illumina flow cell prior to amplification? Is it a splint ligation? The only answer I can get out of Illumina is that there's a "covalent modification" which facilitates attachment. Is anyone aware of what this modification is?

Thanks for the help!

[james hadfield]

If you mean how are the primers attached to the surface of the flow cell then I am not sure, possibly as simple as silanisation or one of the other the methods used for microarray production.
If you mean how does the single DNA lbrary molecule get attached then it is a hybridisation to the oligo on the flow cell followed by Taq extension of this oligo to produce a covalently attached copy of the original molecule. When the first bridge-amplification happens the orgnainl library molecule gets melted off.