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A method involving chitosan-assisted magnetic-stirring-enhanced mechanical amorphous dispersion extraction was developed and utilized to extract hydrophobic anthraquinones from Rhei Radix et Rhizoma prior to ultrahigh performance liquid chromatography analysis. Incorporating natural chitosan as a dispersant facilitated the extraction of hydrophobic anthraquinones using purified water, considerably enhancing the eco-friendliness of the extraction methodology. To optimize extraction efficiency, an extensive evaluation of the crucial parameters influencing rhubarb yield was conducted. Furthermore, a response surface methodology was applied to optimize the extraction conditions. Under these optimized conditions, the method exhibited linearity ranges of 0.1–100 µg/mL, with correlation coefficients between 0.9990 and 0.9998. The method's intraday (n = 6) and interday (n = 6) precision levels were maintained at ≤3.58%, which was considered to be within acceptable limits. The computed detection and quantification limits were 16.54–24.60 and 54.91–82.04 ng/mL, respectively. Consequently, this optimized method was effectively employed to extract five specific compounds (aloe-emodin, emodin, rhein, chrysophanol, and physcion) from Rhei Radix et Rhizoma, achieving recoveries ranging from 86.43% to 102.75%. [Display omitted] • Chitosan-assisted mechanical amorphous dispersion extraction method was developed. • The method shows good practicability for anthraquinone extraction. • Response surface methodology was employed to investigate the extraction conditions. • Water was used as extraction solvent with no environmental pollution. [ABSTRACT FROM AUTHOR]

[Display omitted] • The one-step admicelle to cyclodextrin sweeping method was established. • The approach was applied in the preconcentration of five toxic aristolochic acids. • The method showed low detection limit with 3–6 ng/mL. • The sensitivity enrichment factors of five aristolochic acids was enhanced to 30–68. One-step admicelle to cyclodextrin sweeping (ACDS) method in capillary electrophoresis (CE) has been developed for the separation and preconcentration of toxic aristolochic acids (AAs) by applying cetyltrimethylammonium chloride (CTAC) between the critical micelle concentration and critical surface aggregation concentration. The analytes were captured into the CTAC admicelles, after the more stable inclusion complexes were formed, the release and preconcentration of the analytes could be realized. The CE enrichment parameters, such as the types of cationic surfactants and cyclodextrins (CDs), the concentration of cationic surfactants, disodium tetraborate decahydrate (borax) and CDs, the volume ratio of acetonitrile (ACN) in background electrolyte (BGE) and the sample injection time were optimized systemically. The optimal BGE was composed of 20 mM borax, 10 mM γ-CD and 10 % (v/v) ACN, the sample matrix consisted of 0.2 mM CTAC, 20 mM borax and five analytes. The limit of detection of this method was 3–6 ng/mL, and good linearity values (R2) were obtained for five AAs in the range of 0.997–0.999. Applying optimized conditions, the enrichment efficiencies of five AAs were enhanced with the sensitivity enrichment factors of 30–68. The sweeping approach was successfully applied to the determination of A, B, Ⅶ a , C and D in Aristolochia and Asarum samples, which could provide a potential in the enrichment of the other toxic compounds. [ABSTRACT FROM AUTHOR]

• An on-line enrichment method using γ-CD encapsulated sweeping-MEKC was presented. • Monosaccharides were derivatized with 1-phenyl-3-methyl-5-pyrazolone. • The method can on-line preconcentrate trace monosaccharides in Jujube. • The SEFs ranged from 53 to 82 compared with typical injection. An on-line enrichment and separation of multiple derivatized monosaccharides with cyclodextrin-encapsulated sweeping (CDES) by micellar electrokinetic chromatography (MEKC) was presented. Five monosaccharides (L-(−)-Mannose, D-(+)-Glucose, D-(−)-Ribose, D-(+)-Xylose, and L-(+)-Rhamnose) were derivatized with 1-phenyl-3-methyl-5-pyrazolone, subsequently concentrated and separated by MEKC. The optimized conditions were as follows: 50 mM phosphoric acid (PA), 100 mM sodium dodecyl sulfate (SDS), and 30 % (v/v) methanol in background solution; 140 s injection of sample solution containing 50 mM CD and 100 mM PA, followed by 90 s injection of 40 mM SDS solution. Under the optimized conditions, the correlation coefficients ≥ 0.9953, and the limits of detection ranged from 4.2 to 7.4 ng/mL. Relative standard deviation values ranged from 0.24–4.23 %, and sensitivity enrichment factors were in the range of 53–82 compared with typical injection (50 mbar, 3 s). The CDES-MEKC method was successfully applied to Jujube with good recoveries of 84.22–104.33 %. The method provides new ideas for the on-line enrichment and detection of trace monosaccharides and even other target analytes in foods with complex matrices. [ABSTRACT FROM AUTHOR]