We are pleased to offer custom synthesis of affordable, high-quality non-vanilla oligonucleotides. Generally, we can make all modifications for those the corresponding phosphoramidites or NHS-esters are commercially available. Besides, we have a unique selection of “in-house” monomers (amino linkers, spacers, cleavable spacers, biotin containing, etc.)  that can be incorporated either at the 5′- or 3′-terminal ends and internally within the oligo. Our proprietary MOX/SUC chemistries assure maximum versatility in the design and overall physical properties of the linkers and spacers attached to the oligonucleotides. The oligonucleotides can be individually tailored to meet your requirements in terms of length, flexibility, hydrophobicity, charge density and multiplicity of the tethers. A full range of modifications and possible applications for custom oligonucleotides is outlined below.

Fimer Prep

We love to be challenged! Our laboratory is able to synthesize a wide variety of molecules for oligonucleotide modification, labeling and purification. We would be happy to hear about your specific desired use case and needs. Please fill out our contact form with the specifics of your project, and how we may assist you.


Fidelity Oligos LLC
7965 Cessna Ave
Gaithersburg, MD 20879



Phone: 301-527-0804
Fax: 301-527-8250