Hybridization to 1mer to 150mers. Test of the 5′ sequence fidelity of oligonucleotides up to 150 bases long. A custom array was designed to compare the hybridization characteristics of an 18mer probe sequence (5′-AGGTCATTACAGCGAGAG-3′) synthesized on the 5′ end (solution phase) of different length oligonucleotides. On the X-axis is the length of the total oligonucleotide including the 18mer sequence. The array was hybridized to a biotin-labeled target (5′-biotinCTCTCGCTGTAATGACCT-3′) that was complementary to the 18mer probe sequence. After hybridization, the array was stained with streptavidin-cy3.