Detection of phthalates migration from disposable tablewares to drinking water using hexafluoroisopropanol-induced catanionic surfactant coacervate extraction

Hexafluoroisopropanol(HFIP)-induced sodium dodecyl sulfate/dodecyltrimethylammonium bromide(SDS/DTAB) catanionic surfactant coacervate extraction method coupled with high performance liquid chromatography(HPLC) was used to detect the migration of phthalates from disposable tablewares to drinking water. The concentration factors are larger than 82 and extraction recoveries over 53% for water samples spiked with 100 or 200 ng/m L phthalates. Limit of detection is in the range of 1.0–2.6 ng/m L.Good linearity with correlation coefficients larger than 0.9985 is obtained in the concentration of20–1500 or 40–3000 ng/m L. Relative recoveries are from 82.4% to 123.6% for water samples spiked with30/60, 250/500, and 1500/3000 ng/m L phthalates, respectively. Relative standard deviations(RSDs) are0.4%–7.4% for intraday precision(n = 5) and 0.6%–7.8% for interday precision(n = 3). Four of studied phthalates are found in the drinking water samples prepared from four kinds of tablewares.

Long-chain alkanol-alkyl carboxylic acid-based low-viscosity hydrophobic deep eutectic solvents for one-pot extraction of anthraquinones from Rhei Radix et Rhizoma

Natural long-chain alkanol and alkyl carboxylic acid were used to prepare novel hydrophobic deep eutectic solvents(HDESs).These HDESs are liquid at room temperature and have low viscosity(<12.26 mPa·s),low polarity(lower than that of methanol,ChCl-based deep eutectic solvents and other reported HDESs),and low density(<0.928 g/mL).A simple one-pot method based on a novel HDES-water two-phase extraction system was constructed for the extraction of weak-polarity bioactive components,anthraquinones,from Rhei Radix et Rhizoma.This HDES-based new extraction method does not consume hazardous organic solvents and can obtain a total anthraquinone yield of 21.52 mg/g,which is close to that obtained by the Chinese pharmacopoeia method(21.22 mg/g)and considerably higher than those by other reported HDESs-based extraction methods(14.20-20.09 mg/g,p<0.01).The high extraction yield can be mainly attributed to the severe destruction of the RRR cell walls by the extraction system and the excellent dissolving ability of novel HDESs for anthraquinones.