Preparation of total alkaloid of Rhizoma Corydalis decumbentis-resin complexes

Objective To prepare total alkaloid of Rhizoma Corydalis Decumbentis (traditional Chinese medicine)-resin complexes with effective ingredient extractive of Rhizoma Corydalis Decumbentis total alkaloids.Method A new type of excipient-strong acid cation exchange resin was selected as the drug carrier,and Rhizoma Corydalis Decumbentis total alkaloids as the model drug.Using protopine and tetrahydropalmatine as representative components,the drug-resin complexes were prepared by bath exchange method.The key factors influencing the exchange reaction rate and equilibrium of protopine and tetrahydropalmatine with ion exchange resin were investigated,including anion forms of cation exchange resin,ion concentration of the total alkaloids solution,particle size of the resin,initial drug concentration,and reaction temperature.The combination mechanism of total alkaloids-resin was investigated by differential scanning calorimetry as well.Result The optimal drug-resin complexes preparation conditions with static exchange method were as follows:After dissolving the total alkaloids in 0.1 mol·L-1 HCl,with the initial total alkaloids concentration in solution 8 g·L-1,the drug-resin complexes were prepared with 140 μm H+ cation exchange resin under 50 ℃.Conclusion The differential scanning calorimetry spectrogram showed that the combination force between total alkaloids and resin was ionic bond interaction instead of physical adsorption,and the reaction of protopine and tetrahydropalmatine with the ion exchange resin were ion exchange reaction.