Simultaneous analysis of multiple oligonucleotides by temperature-responsive chromatography using a poly(N-isopropylacrylamide)-based stationary phase.

Oligonucleotide therapeutics have contributed remarkably to healthcare, being well suited for the treatment of intractable diseases that are difficult to approach using conventional drug modalities. However, as common techniques of oligonucleotide analysis rely on reversed-phase or ion-exchange liquid chromatography and thus employ toxic organic solvents and/or ion-pairing reagents, better alternatives are highly sought after. Poly(N-isopropylacrylamide) (PNIPAAm) is widely used in temperature-responsive chromatography (TRC), which relies on column temperature variation to control the physical properties of the stationary phase and, unlike conventional reversed-phase liquid chromatography, avoids the use of toxic organic solvents and complicated gradient methods.