Synthesis and evaluation of dummy molecularly imprinted microspheres for the specific solid‐phase extraction of six anthraquinones from slimming tea

Abstract

Dummy molecularly imprinted microspheres with danthron as template were synthesized and their performance was evaluated. Accelerated solvent extraction can rapidly and effectively remove template molecules from the microspheres. The microspheres were applied as a specific sorbent for solid-phase extraction of six anthraquinones from slimming tea, showing excellent affinity and high selectivity to danthron and the target analytes. The molecular recognition mechanisms were discussed by the experimental validation with IR spectroscopy. The sample was treated using accelerated solvent extraction followed by dummy molecularly imprinted microspheres solid-phase extraction. Under the optimized ultra high performance liquid chromatographic conditions, the six target analytes can be baseline separated in 8 min, and good linearity was obtained in a range of 0.1-40 μg/mL with the correlation coefficient (r(2)) of ≥0.9998. The method limit of quantification was in a range of 1-2 mg/kg, it can ensure analysis of anthraquinones at mg/kg level. The intra- and interday precision (RSD, n = 6) for the analysis of the six analytes in a slimming tea was less than 4.5 and 5.4%, respectively. The developed method can be applied for the selective extraction, effective separation, and rapid determination of six anthraquinones in slimming tea.

Residue investigation of some phenylureas and tebuthiuron herbicides in vegetables by ultra‐performance liquid chromatography coupled with integrated selective accelerated solvent extraction–clean up in situ

“…The MIP samples were degassed in a vacuum at 60 °C prior to adsorption measurements. Static adsorption experiment was carried out according to the literature . The free concentrations of diuron were determined by UV at 245 nm.…”

“…An MISPE column was prepared according to the procedure in the literature . Prior to each extraction, the cartridges were pretreated in turn with 5.0 mL methanol and 5 mL water, followed by loading 3.0 mL of the above extracts.…”

“…Static adsorption experiment was carried out according to the literature. 28 The free concentrations of diuron were determined by UV at 245 nm. The equilibrium adsorption capacity (Q) was calculated according to the equation…”

SPE-UHPLC-FLD Method for the Simultaneous Determination of Five Anthraquinones in Human Urine Using Mixed-Mode Bis(tetraoxacalix[2]arene[2]triazine) Modified Silica as Sorbent

“…Until now, there are many methods that have been conducted for the determination of anthraquinone compounds, such as capillary zone electrophoresis (CZE) [7], capillary electrochromatography (CE) [8], thin layer chromatography (TLC) [9], and micellar electrokinetic chromatography (MEKC) [10, 11]. However, due to its easy operation, high accuracy, and wide applicability, HPLC is still most widely used among these techniques [12–18]. On the other hand, many extraction methods, such as decocting or refluxing extraction [19, 20], liquid–liquid extraction [21], and ultrasonic extraction [22], have been widely applied for the enrichment and cleanup of trace anthraquinones in the complex biological and herbs samples.…”

Molecular Imprinting in Separation Science

“…The properties of magnetic polymers were studied , and the preparation and binding characteristics of several polymers have been included . A group of eight papers is mainly concerned with environmental issues, including analyses of water , food and other samples . Determination of drugs in various matrices is the third group of papers concerning mostly blood and urine.…”