| Macroporous resin adsorption technology, first appearing in the 1960s, is widely used in the separation and purification of active ingredients for its unique advantages, such as simple operational procedures, single-solvent, low pollution, and high purity of the product. Numorous work has been conducted on the application of this techneque in traditional Chinese medicine analysis both from the theoretical and applied aspects. However, these researches are still not very systematic and too preliminary. In view of this, we will comprehensively explore the adsorption behavior of the total alkaloids on macroporous resin which may lay the foundation for the industrial production of alkaloids and provide a thread for separating other effective parts of traditional Chinese medicine. In this paper, Cortex Pheullodendri Chinensis is selected as reserch object. On the one side because it is cheap and easy to get,'on the other side, the material basic research is more mature. Finally, a lot of work has been done to this medicine.The studies are summarized as follows:(1)Using high performance liquid chromatography method to determine berberine hydrochloride, palmatine chloride and jatrorrhizine hydrochloride 's content simultaneously in Cortex Pheullodendri Chinensis. Chromatographic conditions are:Diamonsil 5μm C18 column (250 mm×4.6mm) is used, mobile phase is acetonitrile-lg/L phosphoric acid (50:50) (containing lg/L sodium dodecyl sulfate) with flow rate 1mL/min, detection wavelength is 265nm. Determination results are as follows:berberine hydrochloride is 11.4mg/g herbs, palmatine chloride is 5.85 mg/g herbs, jatrorrhizine hydrochloride is 0.82mg/g herbs. The quality of three kinds of berberine-type alkaloid is accounted for 39.28% to total alkaloids.(2) Using ultraviolet spectrophotometry to determine total alkaloid content in Cortex Pheullodendri Chinensis. Sample preparation is as follows: taking Cortex Pheullodendri Chinensis powder 1.OOg to Soxhlet extractor, 'then adding 90mL methanol and heating until extraction liquid is colorless. The extract liquid is transferred to container of 100mL, adding methanol to the scale volume. Selecting UV detection wavelength is 265nm. The total alkaloid content of Cortex Pheullodendri Chinens is counted as 46mg/g herbs.(3) Extraction process of total alkaloid in Cortex Pheullodendri Chinensis was optimized by orthogonal experiments. Better process conditions are:60% ethanol as extraction solvent with 8BV, distilling 3 times, 1h per time. Under these conditions, the extraction amount of total alkaloids was 38mg/g herbs. Transfering rate is 81.88%.(4) Nine kinds of macroporous resin was selected for screening. Three kinds of resin AB-8, HP20, LD605 have a good effect both in total alkaloid adsorption and desorption. This three kinds of resin were used for furthere selected, the desorption amount of berberine hydrochloride as an inspection-target. The result shows AB-8 is an ideal kind of resin for separating and purificating total alkaloids. AB-8 resin'performance parameters produced by different manufacturers vary in domestic. The AB-8 resin which produced by Ou Rui bio-technology Co., Ltd., Tianjin shows a good effect in absorpting total alkaloids in Cortex Pheullodendri Chinensis and will be served as study object for further research.(5)Adsorption kinetics and thermodynamics of total alkaloids and berberine hydrochloride on AB-8 resin were discussed. Both the dynamic and thermodynamic properties are very similar. The adsorption process of total alkaloids on AB-8 resin tends to be the first order kinetics process. At the conditions of starting concentration 0.686mg/mL, temperature 27℃, the adsorption rate constant k1=2.176 h-1. Process is controled both by film diffusion and in-particle diffusion. A lower temperature, pH, a higher initial concentration, oscillation speed are favourable to adsorp. Adsorption process of berberine hydrochloride on AB-8 resin also tends to be the first order kinetics process. But the adsorption rate is slower than the total alkaloid's. Process is controled both by film diffusion and in-particle diffusion. Adsorption rate rises with the decreasing of temperature and increasing of initial concentration, solution pH, oscillation speed. Experiment also found that the kinetics of berberine hydrochloride in Cortex Pheullodendri Chinensis extraction liquid and in bulk drug were significantly different. The latter fits well first order kinetics equation but the former not. In initial stage, the former's adsorption rate is much faster than the latter's, which indicates palmatine chloride and jatrorrhizine hydrochloride and other 'alkaloids'presence affecting and promoting berberine hydrochloride adsorption on AB-8 resin. Thermodynamic properties of the two are basically the same. The isotherm adsorption experiment shows that equilibrium adsorption capacity increases with the concentration. Lower temperature is more favorable to the adsorption. The isotherm adsorption data fits well Langmuir and Freundlich isotherm which indicate the two are monolayer adsorption on AB-resin.The adsorption is spontaneous exothermic process of physical characters.(6) On the base of dynamics and thermodynamics study, amplification model of macroporous resin column was established, which includes five parts:①mass balance equation (continuity equation);②kinetics equation;③equilibrium equation (isotherm adsorption equation);④boundary conditions;⑤initial conditions. Solving this model obtains numerical solutions and experiment was done to verificate whether the model is exact. The measured data and model simulated data are coincided, indicating the establishment of the mathematical model is accurate, reliable, and can be used for amplification of macroporous resin column.(7)The technical conditions of dynamic adsorption of total alkaloids and berberine hydrochloride on AB-8 resin were optimized. The former is:sample volume is 50mL samples/mL resin, sample concentration is 0.684mg/mL, flow rate is 2BV/h, the amount of impurities eluant is 3BV, eluant is 40% ethanol with 6BV. In these conditions, the purity of total alkaloids is 40.06% and increases 2.56-fold prior to before purification. Berberine hydrochloride adsorption conditions are: sample volume is 55mL samples/mL resin, concentration is 0.576mg/mL, eluant·is 40% ethanol with 6BV.
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