5'-Position Modifications

5'-Phosphate

The unmodified synthesis has only 3'- and 5'-hydroxy groups. 5'-Phosphate oligonucleotides for cloning are offered as a 5'-modification to the regular synthesis.

5'-Amino

5'-Amino modification is a primary amine linked to the carbon-5 of the 5'-ribose via a C3, C6, C12 or C₂OC₂-phosphate-linker. Amino-C4 and -CX are also possible (See “Amino groups and Carboxy-dT” under “Internal or 5'-positions”). Additionally different spacers are possible (See “Spacers” under “Internal or 5'-positions”). Please note that 5'-amino-C3 is not available with HPLC purification.

5'-Biotin

The standard coupling of a Biotin to the 5' end of an oligonucleotide is done including a C6 linker, but C4 or our CXS linker is also optional (See “Biotin” under “Internal or 5'-positions”). Additionally, different spacers are possible (See “Spacers” under “Internal or 5' positions”).

5'-Thiol

The 5'-Thiol modification is linked to the 5'-carbon of the ribose via a C6-phosphate-linker. 5'-Thiololigonucleotides are delivered dry and trityl-protected. Protocol for removal of the trityl-group prior to use is supplied. The Thiol modification can also be obtained from a disulfide (See “Miscellaneous” under “Internal or 5'-positions”). For more spacing different spacers are possible (See “Spacers” under “Internal or 5'-positions”).

5'-Fluorescent Dyes

Please refer to our dye selection chart for available 5’-fluorescent dyes modifications. 5' modification with dyes includes the fluoresceins ABI-dyes HEX, TET, 6-FAM and the VIC analog CAL Fluor® Orange, the Rhodamines TAMRA and ROX, the Texas Red analog CAL Fluor Red 610 and the LC Red 640 analog CAL Fluor Red 635.

Abs. coef.: Molar Extinction Coefficient x 1000 (cm-1M-1)