Integrated DNA Technologies
We synthesize our oligos using a home-built DNA synthesizer with the highest coupling efficiency (>99.6%) in the market. Every oligo is deprotected and desalted to remove small molecule impurities. Oligos are quantitated twice by UV spectrophotometry to provide an accurate measure of yield. This mass yield, as measured in Optical density (OD), varies with length and decreases for shorter oligos.
Since every synthesis is unique and quality is our highest priority, ALL our oligos are quality control (QC) checked by mass spectrometry. Enormous investments lead to the development of two innovative MS platforms to allow the most accurate measurements for oligonucleotides. Mass spectrometry is the only cost-effective method to QC for correct length of a sequence and although MALDI-TOF only is considered as ‘the standard’, it is only useful for compounds up to ~15 kDa, or about a 40-mer oligonucleotide. Samples >15 kDa do not ionize/fly effectively and, additionally, are outside the optimal resolution range of these instruments making the data less accurate. Electrospray Ionization (ESI-) MS is 12 to 15 times more sensitive than Maldi-TOF and can therefore resolve longer oligos. However this technique required a high-throughput setting which we obtained in collaboration with MS device developer Novatia.