Selective isolation of in vitro phase II conjugates using a lipophilic anionic exchange solid phase extraction method

Quantitation of Gingerols in Human Plasma by Newly Developed Stable Isotope Dilution Assays and Assessment of Their Immunomodulatory Potential

“…For quantitation an aliquot (1 mL) was spiked with [ 2 H 4 ]-1 (60.4 nmol), [ 2 H 4 ]-2 (2.78 nmol), and [ 2 H 4 ]-3 (2.64 nmol) and equilibrated for 45 min at room temperature. Gingerols were isolated using solid phase extraction (SPE), according to the method of Gagné et al For this, tea samples (1 mL) were applied to a mixed phase anion exchange SPE cartridge (Oasis Max 500 mg, 6 cm 3 ) (Waters, Eschborn, Germany) conditioned with 4 × 5 mL of 2% formic acid in methanol, 4 × 5 mL of methanol, 3 × 5 mL of 5% aqueous ammonium hydroxide, and finally 3 × 5 mL of water. The samples were washed with 5% ammonium hydroxide solution (15 mL total) and dried for 10 min, before sequential elution with 4 × 5 mL of methanol.…”

Glucuronides from metabolites to medicines: a survey of the in vivo generation, chemical synthesis and properties of glucuronides

“…Due to the pK a differences between the parent compound, and the negatively charged glucuronide and/or sulfate metabolites, 17-ethynylestradiol-3-glucuronide 197 and 6-gingerol-4-glucuronide 198 have been successfully isolated in high purity. 241 Furthermore, in order to facilitate the trace enrichment of analytes, molecularly imprinted solid phase extraction (MISPE) has been utilized in the selective extraction of target compounds. 242 Additionally, in some cases when a low quantity of sample is available, microelution SPE plates (mSPE) that use an ultra-low elution volume become useful for the rapid isolation of analytes from complex matrices.…”

Current trends in environmental analysis of human metabolite conjugates of pharmaceuticals

“…Additionally, NMR lacks the sensitivity needed for environmental applications, as exemplified by the single reported LOD value of 150,000 ng/L [30] in analyzing EE2-3-glucuronide and 6-gingerol-4-glucuronide.…”

“…Other HPLC techniques such as capillary liquid chromatography [27], mixed phase anionic exchange lipophilic stationary phase liquid chromatography [30], and ZIC-HILIC [31,32] are also included. Of these, HILIC seems to be the most promising for future pharmaceutical analysis.…”

“…The majority of the eight studies employing Q-ToF qualitatively analyzed for unknown metabolites of pharmaceuticals [40], triclosan [38], lamotrigine [46], dextromethophan [3], estrogens [18,30], and steroids [34]. The latter three studies also quantified conjugates using Q-ToF.…”