Improved chemical stabilities for end-capped high performance liquid chromatography stationary phases based on poly(methyloctadecylsiloxane) thermally immobilized onto metalized silicas

Permeation profiles of resveratrol cream delivered through porcine vaginal mucosa: Evaluation of different HPLC stationary phases

“…Although the commercial columns packed with octadecyl-bonded silica (C18) has traditionally been the most employed stationary phase (SP) for resveratrol analysis, our group has been utilizing silica-oxide materials (SiO 2 -Zr or SiO 2 -Ti) as chromatographic supports for SP in HPLC with considerable success [10][11][12]. Using this process, the primary objective of this work was to evaluate the possibility of vaginal creams to successfully deliver trans-resveratrol to the blood stream viaanex vivo permeation experiment.…”

“…Separation was achieved at 25°C using a ZORBAX Eclipse XDB-C18, 250 × 4.6 mm, 5 μmcolumn (Phenomenex Inc., Torrance, California); a 250 × 4.6 mm, 5 μm column containing Zr-PMODS as described by da Silva & Collins[10,11]; or a 250 × 4.6 mm, 5 μm column containing PMODS thermally immobilized onto the surface of porous titanized silica particles as described by da Silva & Collins[12]. The mobile phase entailed a mixture of acetonitrile and water (50:50, v/v) at a flow rate of 1.2 mL min -1 .…”

New stationary phase for capillary liquid chromatography based on polydimethylsiloxane immobilized onto a Monolithic Silica Support

“…The immobilization, especially of polysiloxanes, onto supports of particulate silica or silica modified with a metal, such as zirconium or titanium , has already been applied in HPLC employing different polymers: poly(methyloctylsiloxane) (PMOS), PDMS, poly(methyltetradecylsiloxane) (PMTDS), poly(methyloctadecylsiloxane) (PMODS), poly(methylphenylsiloxane) (PMPS), and polybutadiene (PBD). This process has the aim of improving the chemical stability of the stationary phase and of reducing silanol group activity, thus avoiding those groups that interact strongly with basic analytes and cause band broadening .…”