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Objective::To compare the adsorption characteristics of different macroporous adsorption resins for the total flavonoids in Epimedii Folium, clarify the adsorption mechanism, and screen the optimal resin for the purification of total flavonoids in Epimedii Folium. Method::Taking the adsorption and desorption capacities of the total flavonoids in Epimedii Folium and five representative flavonoids (epimedin A, epimendin B, epimendin C, icariin, baohuoside Ⅰ) as indexes, static adsorption and dynamic adsorption experiments were conducted to compare the adsorption characteristics of five macroporous including HPD100, HPD600, AB-8, X-5 and D101.The adsorption kinetics of the selected resin was studied by using the pseudo-first-order, pseudo-second-order kinetic models and intraparticle diffusion model, and the thermodynamic process was analyzed by using the Langmuir and Freundlich isothermal adsorption models, which explored the adsorption mechanism of resin from the perspective of physical chemistry. Result::HPD100 macroporous resin had a better adsorption and desorption properties than the others. The adsorption process of HPD100 macroporous resin for total flavonoids in Epimedii Folium and five representative flavonoids conformed to the pseudo-second-order kinetic model. The adsorption thermodynamic process of HPD100 resin for total flavonoids of Epimedii Folium conformed to the Freundlich model, and for the sum of five representative flavonoids conformed to the Langmuir model. The adsorption process of HPD100 resin for total flavonoids in Epimedii Folium was the exothermic process dominated by physical adsorption, and the optimal adsorption temperature was 25 ℃. Conclusion::HPD100 macroporous resin has large adsorption capacity, easy desorption and clear adsorption mechanism, it is suitable for isolation and purification of total flavonoids in Epimedii Folium.
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OBJECTIVE:To synthesize 4-hydroxyphenylacetic acid(PHPAA)molecular imprinted polymers(MIPs),and to provide reference for separation and enrichment of PHPAA in urine of cancer patients. METHODS:With PHPAA as template molecule and azobisisobutyronitrile as evocating agent,MIPs was synthesized by precipitation polymerization using 4-vinyl pyridine(4-V),acrylamide(AM),1-vinyl imidazole(1-V)and o-diaminobenzene as functional monomers,ethylene glycol dimethacrylate(EGDMA)and trimethylolpropane trimethacrylate(TRIM)as crosslinking agent. Using scanning electron microscope,infrared spectrum,static adsorption test and molecular recognition performance test used adopted to characterize the structure and performance of MIPs. RESULTS:MIPs1(4-V,EGDMA)microspheres adhered seriously,and MIPs2(AM, EGDMA)microspheres are aggregated. MIPs3(1-V,TRIM),MIPs4(o-diaminobenzene,TRIM)microspheresare were dispersed and had good sphericity. Characteristic absorption peak of PHPAA was not found in infrared spectrum of MIPs. The adsorption capacity of each MIPs was higher than that of blank imprinted polymer without the template molecule,and increased as the increase of template molecular concentration. The adsorption capacity of MIPs3 was significantly higher than that of other MIPs,and its static distribution coefficient(0.14)of PHPAA was higher than that of other structural analogues [PHPA(0.06),TA(0.01)],selective separation factors of PHPAA to PHPA,PHPAA to TA were 2.3,11.5,respectively. CONCLUSIONS:MIPs synthesized with 1-V as functional monomer and TRIM as crosslinking agent has the ability of specific adsorption and selective recognition. It can used as solid phase extractant to separate and enrich low content of PHPAA in the urine of tumor patients.
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Objective To prepare surface molecular imprinted polymers (MIP) of galangin by using surface molecular imprinting technique. Methods Galangin MIP was prepared by surface polymerization method at the surface of silica gel, which was modified with (3-aminopropyl) trimethoxysilane, by using galangin as the template molecule, methacrylic acid (MAA) as the functional monomer, and N,N′-methylenebisacrylamide (MBA) as crosslinking agent. The polymer was characterized by infrared spectroscopy and scanning electron microscopy. And its adsorption properties were studied by static and competitive adsorption method. Results The experimental research showed that the optimal preparation condition was that the molar ration of galangin to MAA was 1∶4, with molar ration of MAA to MBA 1∶7, reaction temperature 40 ℃ and reaction time 12 h. Infrared spectrum and scanning electron microscopy showed that MIP was successfully grafted on the surface of silica gel, and recognition holes and sites selectively appeared for galangin molecules. Adsorption experiments exhibited that MIP had specific recognition and good affinity for galangin molecules. Compared to the controls of breviscapine and luteolin, the selectivity coefficients of MIP to galangin were 11.2 and 5.3, respectively. Conclusion MIP has good recognition and high selectivity for galangin, which provides a new method for the separation and extraction of flavonoids from Chinese medicine.
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Objective To study the effect of humic acid (HA) and soil on dissolution performance of depleted uranium (DU).Methods Using the static dissolve-adsorption experiment and inductively coupled plasma-mass spectrometry(ICP-MS) to determine uranium concentration and 235U/238U isotope ratios of the samples at different time and study the dissolution of DU in water.Results The solubility of DU in water was reduced by 90％ by adding HA.Soil could increase the solubility of DU in water by nearly 25％,adding an appropriate amount of HA could play a supporting role on the dissolution of DU,in this experiment adding 5％ of HA was best.Conclusions Soil and HA could produce positive and negative impact on the solubility of DU in water,and the combined effect of the two relied on the complex absorption and complexation reactions of soil,HA and dissolved uranium ions.
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Objective: To research the adsortpion and separation function of ion-exchange resin on 5-hydroxytryptophan (5-HTP) in extract from the seeds of Griffonia simplicifolia and to screen the ion-exchange resin with high selective adsorption. Methods: The static adsorptive properties of eight different types of ion-exchange resins were evaluated using adsorptive content, desorption rate, adsorption rate, and adsorption temperature as indexes in order to optimize the resin. And the effects of different pH values, injection rates, injection concentration, eluent concentration, and elution rates on adsorptive properties of resins were investigated. Results: The 001 × 7 cation exchange resin showed the best comprehensive adsorption property. The loading solution concentration was 10.8 mg/mL, the pH value was 3.5, the flow rate of loading solution was 4.0 mL/min, and 3BV 7.0% ammonia water solution in 3.0 mL/min velocity was used to elute. In this process, the product was obtained with the 5-HTP purity of greater than 99.0% and the ash content of less than 1.0%, product average yield was 7.95% and the product quality could meet the market demand. Conclusion: The 001 × 7 cation exchange resin shows a better comprehensive adsorption property. It could be used to isolate and purify the 5-HTP for scale production.
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OBJECTIVE: To screen the best macroporous adsorptive resin for separation and purification of flower Elaeagnus angustifolia flavonoids and to establish the purification process parameters. METHODS: Using macroporous adsorption resin adsorption rate and desorption rate as the indexes, the best resin was screened out for enriching flower Elaeagnus angustifolia flavonoids. The optimal process conditions were investigated through single factor test. RESULTS: DA201 resin showed good adsorption and separation property for Elaeagnus angustifolia flavonoids. The detailed process conditions were as follows: the ratio of diameter to height of resin column was 1:8, sample loading rate was 0.5 mL·min-1, sample concentration was 20 mg·mL-1, pH was adjusted to 4, with elution rate of 0.5 mL·min-1, the largest sample load was 4.5 BV, eluent concentration was 80% and the dosage was 12 BV. CONCLUSION: DA201 type resin, showed good purification effect for flavonoids Elaeagnus angustifolia in the defined process conditions with a yield of 85.23%. The purity of total flavonoids achieved 14.95%, which was 3 times of that by coarse extraction (4.901%). Copyright 2012 by the Chinese Pharmaceutical Association.
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Objective: To optimize the technological parameters of separation and purification of cynarin from Cynara scolymus leaves. Methods: Seven different types of macroporous adsorption resins were evaluated on absorptive capacity, desorption rate, and adsorption rate in order to select the best resin and the conditions of the best resin to separate and purify cynarin were researched. Results: It was found that LSA-21 resin showed better comprehensive adsorption property, flow rate of sample loading was 2 BV/h, 3 BV/h 50% alcohol aqueous and 2 BV/h velocity was used to elute. In this process to obtain the product with purity of 5.63% cynarin, ash content of 0.61%, product yield 5.56%, the product quality could meet the market demand. Conclusion: The LSA-21 macroporous adsorption resin shows better comprehensive adsorption property. It could be used to isolate and purify the cynarin.
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AIM:To review the 10 kinds of macroporous resin's absorption of total flavnoids to screen out the one which could separate the Baicalin,Baicalein,Wogonoside,Wogonin simultaneously. METHODS: By HPLC,using the content of Baicalin,Baicalein,Wogonoside,wogonin as the marker,adopting a static adsorbtion in combination with dynamic state. RESULTS: The difference in adsorption and desorption among macroporous resins and adsorption condition arose from four kinds of flavonoids. CONCLUSION: At a comprehensive estimate SP-825 resin was regarded as the ideal for adsorption and desorption.
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AIM: To study the influencing factors of static adsorpting process of extract of Herba Artemisiae scopariae with macroporous resin,and determine the refinement process. METHODS: The absorbances and the adsorption quantity of caffeotannic acid were used as indexes,the adsorption effect of 9 kinds of macroporous resin and static adsorption curve of F resin;density and pH of the extract liquor were investigated by use of factorial experiment;HPLC fingerprint of extract of Herba Artemisiae scopariae were evaluated the adsorption effect.(RESULTS:) The adsorpting effect were different among types of macroporous resin,and the adsorpting equilibrium time was 6 h in the use of F resin;Density and pH of the extract liquor are important factors of adsorption;The experiment indicated that decreased liquor by this process were important factors of adsorption;The experiment indicated that this process decreased the yield of extract by 2.5%. CONCLUSION: The result can offer information about the determination of refinement process of extract of Herba Artemisiae scopariae with macroporous resin.