Abstract:

A thermal sensitive bonded stationary phase, poly(N-isopropylacrylamide) bonded silica gel stationary phase (SI-PNIPAM), was prepared by reacting silica gel with 3-mercaptopropyltrimethoxysilane (MPS). The characterization of the prepared packings was carried out with elemental analysis and Fourier transform infrared (FT-IR) spectroscopy. The chromatographic evaluations were carried out by testing with polycyclic aromatic hydrocarbons and basic compounds using methanol-water as a binary mobile phase. The applicable range of pH and stability of SI-PNIPAM were also evaluated. The results showed that the stationary phase has excellent chromatographic properties, thermal-responsibility and resistance to hydrolysis between pH 2.5 and 7.5. It can be used to separate basic solutes efficiently due to the existence of the special structure containing internal polar amide group contributing to restraining the activity of the residual silanol group below the lower-critical-solution temperature (LCST).

Key words: bonded stationary phase , reversed-phase high performance liquid chromatography （RP-HPLC）, silica gel, poly(N-isopropylacrylamide)