Patent ID: 6844151

Claim:
An array comprising: (A) a support surface; and (B) a plurality of modified oligonucleotide compositions, each composition comprising a plurality of oligonucleotides stably associated with a distinct area of the support surface, wherein the oligonucleotides of each composition are characterized by: (1) independently having a length of from about 20 to about 300 nucleotides; (2) having internucleotide linkages selected from the group consisting of 2′-O-alkyl, 2′-O-alkyl-n(O-alkyl), combinations thereof; (3) having a binding affinity to a complementary sequence greater than the corresponding binding affinity of a non-modified oligonucleotide having the same sequence; and (4) having a pH stability of at least one hour at 37° C. at a pH in a range of about 0.5 to 6.