Abstract: | Phenolic compounds are one of the major compounds in Laminaria japonica Aresch. Solid-phase extraction was used to separate the two phenolic compounds (4-hydroxybenzoic acid and 4-hydroxybenzaldehyde). A new monolithic sorbent was developed and used successfully as a special sorbent in a solid-phase extraction process. The effects on different SPE cartridges using silica, C18, and monolithic were compared. Quantitative analysis was carried out using a C18 analysis column (5 µm, 150 × 4.6 mm). Good linearity was obtained for the two targets, ranging from 0.5 to 100 µg mL?1 (r 2 > 0.999), with relative standard deviations <4.7%. |