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To optimize the extraction process of fucoidan from Saccharina japonica, an orthogonal test with four factors and three levels was designed in the present experiment. The results showed that the highest extraction yield was obtained under the following conditions: extraction temperature, 90 °C; extraction time, 1.5 h; number of extractions, 3; and pH of the extraction solution, 2.5. Furthermore, a capillary zone electrophoresis method using a UV detector was established for the analysis of the monosaccharide composition of fucoidan via 1-phenyl-3-methyl-5-pyrazolone derivatization. The results showed that fucoidans found in the three different samples all consisted of xylose, rhamnose, fucose, mannose, galactose, and glucuronic acid, while the mole ratios of monosaccharide components revealed differently. Moreover, fucose and galactose were found to be the most abundant monosaccharides in the samples. The above results could be further used for in-depth study on the mechanism of biological activity of fucoidan from S. japonica. [ABSTRACT FROM AUTHOR]

Abstract: A simplified method for mobility determination of electroosmotic flow (EOF) of polymethyl methacrylate (PMMA) microfluidic chips is developed with indirect laser-induced fluorescence detection (IDLIFD). Based on the interval between the beginning of separation and the apex of converse peak, the present technique highlights in circumventing the great demand for sensitivity and baseline stability of routine methods. IDLIFD is performed by a home-made laser-induced fluorescence detector of confocal optical configuration, mainly composed of a 473nm laser diode double-pumped solid state laser (LD-DPSSL) and a 520nm band-pass interference filter. Amino acetate (NH4Ac) solution containing Vitamin B2 is used as the background fluorescent reagent (BFR) solution. The pre-treatment procedures of chip inter-surface and the voltage program of injection and separation are studied. Reasons for the low background fluorescent response during injection are also discussed. Even this phenomenon has a good effect on the accurate recording of the interval between the baseline starting of separation and the lowest point of the converse peak. The results demonstrate that the reciprocals of EOF mobility (υ eo) of PMMA microfluidic chip are in line with the ion strength of background electrolyte (BGE) solution. Furthermore, the υ eo of PMMA material is related to the pH of BGE solution. Compared with those results obtained from the Current-Monitoring method, no apparent difference has been found. [Copyright &y& Elsevier]

A new method lo separate and determine the contents of troxerutin in troxerutin tablets by monolithic capillary electrochromatography (MLCEC) was established. The composition of the mobile phase, pH, its type and concentration, differently influenced the peak efficiency and resolution, and selectively modulated the interaction of analytes with the stationary phase. In the method, a poly butyl methacrylate (PBMA) column (total length was 31.5 cm. effective length was 22.0cm) was used. A mixture of 35 mM horax and acetonitrile (50/50) was used as the mobile phase. A pressure injection of 12 bar × 0.1 min of test solutions followed by an 8 bar × 0.1 min of the mobile phase was employed. The capillary temperature was 35 C and the operational voltage was 16 kV, The detection wavelength was set at 254 nm. Thiourea was used as the inner standard. The calibration curve showed good linearity over the range of 0.2022 ∼ 0.8088 mg - mL-1 (r = 0.9991); three level average recoveries were 100.9%, 98.9%, and 97.4% with RSD being less than 4.0%. respectively; LOD was 2.2μg mL-1 and LOQ was 7.3μg mL-1. The method was simple, rapid, accurate. reproducible with low consumption, and could be applied to the quality control of troxerutin tablets. [ABSTRACT FROM AUTHOR]

Compound Chinese medicine preparation is a complex multi‐component system. The traditional methods such as physicochemical identification and quantification of several main index components cannot provide adequate quality evaluation for Compound Banlangen Granules. The objective of this work was to establish a characteristic degradation fingerprint of Compound Banlangen Granules polysaccharides, and the reference fingerprint was obtained from the model samples prepared using prescription medicinal herbs from different origins. The partial degradation products of Compound Banlangen Granules polysaccharides were profiled by capillary zone electrophoresis, and the quality difference of polysaccharides of these preparations was compared by cluster analysis and principal component analysis. It was found that the contents and the characteristic degradation fingerprints of the polysaccharides from 25 batches of Compound Banlangen Granules of 17 manufacturers were significantly different. The quality of Compound Banlangen Granules polysaccharides was evaluated by the characteristic degradation fingerprint tool with satisfactory results. The present method provides a reference for the quality control strategy development of polysaccharides in other compound Chinese medicine preparations. [ABSTRACT FROM AUTHOR]

Using orthogonal design, optimized conditions for the hydrolysis of the polysaccharide from Radix Asparagi were determined, as well as its monosaccharide composition. Optimized hydrolysis conditions were a temperature of 100°C in 1.5 M sulfuric acid solution for 5 h. The resulting monosaccharides were derivatized with 1-phenyl-3-methyl-5-pyrazolone, then separated by capillary zone electrophoresis in 40 mM sodium tetraborate buffer (pH 10.1), and detected by ultraviolet absorption at 245 nm. Results indicate that the polysaccharide from Radix Asparagi is composed of xylose, arabinose, glucose, rhamnose, mannose, galactose, glucuronic acid, and galacturonic acid, which differs from published findings. Moreover, xylose, glucuronic acid, and galacturonic acid have not been previously reported in Radix Asparagi polysaccharide. This method is simple, fast, and yields a highly efficient separation. As well, these findings can be applied to quality control of Radix Asparagi and for in-depth study of the biological activity of Radix Asparagi polysaccharide. [ABSTRACT FROM AUTHOR]

Natural glycosides widely distributed in medicinal plants are valuable sources of therapeutic agents, showing various pharmacological effects. The separation and purification of natural glycosides are meaningful for their pharmacological research, which face with great challenges due to the complex of medicinal plants samples. In this work, two kinds of functional monolithic separation mediums A and S were fabricated and fully applied in the online extraction, separation and purification of active glycoside components from medicinal plants with a simple-procedure closed-loop mode. Chrysophanol glucoside and physcion glucoside were detected and separated from Rhei Radix et Rhizoma using separation medium A as a solid-phase extraction adsorbent. Rhapontin was isolated and purified from Rheum hotaoense C. Y. Cheng et Kao using separation medium S as the stationary phase of high-performance liquid chromatography. Compared to the reported literatures, high yield of 5.68, 1.20 and 4.76 mg g−1 of these three products were obtained with high purity. These two online closed-loop mode methods were carried out using high-performance liquid chromatography system, in which the sample injection, isolation and purification procedures are all online mode, and reduced loss compared to offline extraction and purification procedures, thus achieving high recovery and high purity. [Display omitted] • Separation mediums were fabricated aiming to the structures of natural glycosides. • Separation were achieved via semi-preparative HPLC system based on the mediums. • The present method reduces production loss using an online closed-loop recovery mode. • The isolated products were obtained with a high yield and high purity. [ABSTRACT FROM AUTHOR]

Highlights • Diallyl maleate is introduced for the first time to prepare a polymer-based monolith. • The monolith presents a macroporous structure with a reversed-phase mechanism. • The interference of the three most abundant proteins in human plasma is avoided. • There is good correlation between the retention time and protein hydrophobicity. • Identification by LC/MS shows the method's importance in plasma proteomic research. Abstract A monolithic diallyl maleate-based column was developed and used to separate intact proteins from complex bio-samples with high-performance liquid chromatography. The resulting monolith exhibited a relatively uniform porous structure with macro-pores. A sample of standard proteins mixture was used to explore the reversed-phase mechanism for fast separation on the homemade monolithic column. The observed retention time increased with the values of the diameters, relative hydrophobicities and molecular weights of the standard proteins, which mainly depends on the relative hydrophobicity of the proteins. It is worth mentioning that the mask of the three most abundant proteins in human plasma can be avoided, thus providing an opportunity for the middle- and low-abundance proteins to be detected. According to this exploration, the fast separation of human plasma proteins on the diallyl maleate-based monolithic column was achieved in 15 min. The chromatographic fractions were identified by liquid chromatography-tandem mass spectrometry, and the results indicate that the present method is an outstanding method for the fast and efficient fractionation of human plasma that will be significant sense for plasma proteomics research, especially for exploring new disease marker and drug target. [ABSTRACT FROM AUTHOR]

Highlights • A polymer monolithic column was prepared by in-situ free radical polymerization. • The monolith was used for on-line enrichment and determination of β-sitosterol. • The maximum adsorption capacity was 12.69 mg/g, and the enrichment factor was 78. Abstract A novel monolithic column was prepared by in-situ free radical polymerization using N -methylolacrylamide (NMA) and N , N -diethylacrylamide (DEA) as co-monomers. The monolith was characterized by scanning electron microscopy (SEM) and its nitrogen adsorption-desorption isotherm, and it was used as a solid phase extraction (SPE) absorbent for the online enrichment of β-sitosterol by high performance liquid chromatography. The optimized method had good linearity, and the linear regression coefficient was 0.998. The limit of detection (LOD) and the limit of quantification (LOQ) were 0.006 mg/mL and 0.02 mg/mL, respectively. The interday and intraday accuracies were less than 7.28%. The spiked recoveries of β-sitosterol in the six plant oil were 90.96–103.56%. The maximum amount of β-sitosterol adsorbed on the monolithic column was 12.69 mg/g, and the enrichment factor of β-sitosterol was 78. The results showed that the monolith could be used as an online SPE absorbent for the determination of β-sitosterol in plant oil samples. [ABSTRACT FROM AUTHOR]

Abstract The fabrication of a monolithic allyl phenoxyacetate-based material was proposed via the in situ radical polymerization using ethylene dimethacrylate as the crosslinker and 2,2′-azobisisobutyronitrile as the initiator within a stainless steel column (50 mm × 4.6 mm i.d.). The effects of the porogen composition, the crosslinker amount and the monomer type on the resulting monoliths were investigated. The morphology of the monoliths was characterized using scanning electron microscopy and a nitrogen adsorption-desorption instrument, and the pore structure was characterized using mercury intrusion porosimetry. The results indicate that the optimized monolith has a micro-, meso- and macro- multi-sized pore structure with a high specific surface area of 260.66 m2 g−1. The resulting monoliths were used as stationary phases for the separation of proteins from bio-samples, including a mixture of six standard proteins, chicken egg whites, snailase and human plasma, using high-performance liquid chromatography. Compared to optimized glycidyl methacrylate-based and styrene-based monolithic columns, the allyl phenoxyacetate-based monolithic column exhibited improved selectivity in the separation of proteins. Furthermore, the present method avoids the masking of highly abundant proteins, such as human serum albumin, immunoglobulin G and human fibrinogen, in the detection of middle- or low-abundance proteins in human plasma. The protein identification results obtained from liquid chromatography/mass spectrometry indicate that the present method is an outstanding method for efficient fractionation of human plasma, which will be especially useful in future plasma proteomics research. Graphical abstract fx1 Highlights • Allyl phenoxyacetate is introduced for the first time to prepare a polymer-based monolith. • The monolith presents a multi-dimensional porous structure with high surface area. • Interference of three high-abundance proteins can be avoided using the monolith. • Identification by LC/MS shows this method's importance in plasma proteomic research. [ABSTRACT FROM AUTHOR]

Abstract In this work, a monolithic hydroxyethyl-based column was fabricated in a stainless-steel column (50 mm × 4.6 mm i.d.) via radical polymerization technique using hydroxyethyl methylacrylate as the monomer. The morphology and pore size distribution indicate that the optimized monolith has a relatively uniform structure with macro-pores. The homemade monolith was used as the stationary phase of high performance liquid chromatography for the separation of intact proteins from complex bio-samples, including human plasma, egg white and snailase. The resulting monolith shows excellent selectivity for intact proteins mainly depending on the different relative hydrophobicity of the objective proteins with reversed-phase liquid chromatographic mechanism. Besides, the hydrogen-bond interaction and electrostatic interaction were the additional interactions in the chromatographic separation owing to hydroxyl groups present in the surface of monolithic material. Graphical abstract Unlabelled Image Highlights • A polymer-based monolith containing hydroxyl groups has been prepared; • Masking of three highest-abundance proteins can be avoided by the present method; • Providing alternative and efficient method for proteins in complex bio-samples. [ABSTRACT FROM AUTHOR]

Highlights • Amino acid and ionic liquid modified POSS-based monolithic column was developed. • The column exhibited reduced hydrophobicity with introduction of polar L-cysteine. • Polar compounds could be efficiently separated under RPLC mode. • Intact proteins exhibited strong retention and good separation selectivity. Abstract In this study, a novel amino acid and ionic liquid dual organically functionalized reagents modified polyhedral oligomeric silsesquioxane methacryl substituted (POSS-MA) based hybrid monolithic column (POSS-VBI-Cys) was designed and reported. With amino acid L-cysteine and ionic liquid 1-vinyl-3-butylimidazolium bromide as dual monomers, POSS-MA as the crosslinker, the new POSS-VBI-Cys hybrid monolithic column could be facilely fabricated via the “one-pot” free radical copolymerization and thiol-ene click reaction. Because of the introduction of polar amino acid L-cysteine, the new POSS-VBI-Cys column exhibited attenuated hydrophobicity in reversed-phase liquid chromatography separation. Polar amides, nucleosides and nucleic acid bases displayed strong retention on the POSS-VBI-Cys column and could be successfully separated. Furthermore, the new POSS-VBI-Cys column displayed good separation selectivity for model glycoproteins and non-glycoproteins mixture and it was also successfully used for the purification and separation of TARG1 protein from its originally expressed sample. In the future research, we will further exploit its performances for separation of intact proteins and in-depth proteome applications. [ABSTRACT FROM AUTHOR]

• Porous organic cage was introduced to the preparation of a monolithic adsorbent. • The homemade adsorbent shows rich interaction sites and high surface area. • Efficient extraction of three terpenoids was achieved by an online SPE-HPLC method. • Fabricated a reusable monolithic cartridge, which can be used for at least 100 times. • Present method show good matrix-removal ability and good terpenoids-retention ability. A monolithic solid-phase extraction (SPE) cartridge packed with a composite adsorbent was fabricated via polymerization using dodecene as the monomer with the porous organic cage (POC) material doped, combing with an analytical column through a high-performance liquid chromatography (HPLC) instrument, which was used for the online extraction and separation of 23-acetyl alismol C, atractylodes lactone II and atractylodes lactone III from Zexie Decoction. The POC-doped adsorbent shows porous structure with a relatively high specific surface area of 85.50 m2/g, which was obtained from the characterizations of a scanning electron microscope and an automatic surface area and porosity analyser. Efficient extraction and separation of three target terpenoids was achieved by an online SPE-HPLC method based on the POC-doped cartridge, which exhibits strong matrix-removal ability and good terpenoids-retention ability with a high adsorption capacity, due to the interactions of hydrogen bond and hydrophobicity between the terpenoids and the POC-doped adsorbent. Method validation shows good linearity (r ≥ 0.9998) of the regression equation, and high accuracy with the spiked recovery in the range of 99.2 %-100.8 % of the proposed method. Compared to the generally disposable adsorbent, this work fabricated a reusable monolithic cartridge, which can be used for at least 100 times, with the RSD based on the peak area of the three terpenoids less than 6.6 %. [ABSTRACT FROM AUTHOR]

Abstract: The central composite design (CCD) was applied to optimize the water extraction of the polysaccharide from Adenophorae Radix in the paper. The three variables of extraction temperature (X 1), extraction time (X 2) and ratio of water to raw material (X 3) were investigated by single factor analysis first. Since the presence of active polysaccharides and the imperfect of its extraction, the purpose of the paper was to evaluate the effects of selected variables on the yield of polysaccharide, which was expected to obtain the maximum yield. By variance and regression analysis, the quadratic regression equation was established as a predicted model. The R 2 of 0.9825 indicated that the equation was well-fitted. The optimal conditions were 72.5°C, 133min, 1:35 (g/mL) and the predicted maximum yield of the polysaccharide was 5.78%. The predicted value was verified in triplicates under the optimum conditions, which was 5.68% and well matched with the predictive yield. [Copyright &y& Elsevier]