Conjugates of PMO of Pip6a, Pip6b, Pip6e, and Pip6f were found to be predominantly stable and of similar stability to Pip5e-PMO in 100% serum for 2 hours at 37 °C, as seen by high-performance liquid chromatography and MALDI-TOF mass spectral analysis. The conjugates all showed similar degradation patterns, and intact conjugates were still observed up to 4 hours (data not shown).