氨基表面修饰磁性纳米粒子(MNP-NH_2)对黄酮类和有机酸类成分选择吸附研究

Preferential adsorption of flavonoids and organic acids by amino-modified Fe_3O_4 nanoparticles(MNP-NH_2)

目的制备氨基表面修饰磁性纳米粒子(amino-modified Fe_3O_4 nanoparticles,MNP-NH_2)并将其作为吸附剂,研究其对黄酮类及有机酸类成分的吸附性能。方法制备MNP-NH_2磁性纳米粒子,扫描/透射电镜、傅里叶红外光谱仪及振动样品磁强计对其结构进行表征;通过研究对12种单体成分吸附性能探讨MNP-NH_2的吸附规律;将其应用到金银花药材中,研究超声时间、温度、离子强度及p H值对吸附能力的影响,采用L9(34)正交试验考察MNP-NH_2对金银花5种成分的洗脱条件,并研究其循环利用性能。结果制备的MNP-NH_2结构稳定、分布均匀,有良好的磁性;其吸附量与黄酮类、有机酸类化合物邻位酚羟基存在和个数有关;离子浓度和温度对吸附过程几乎无影响,p H值对不同类化合物的吸附过程影响较大,最佳吸附条件为30℃下超声40 min,洗脱条件为5 m L 20%冰乙酸溶液(甲醇-水60∶40)的洗脱液,超声40 min。结论 MNP-NH_2可用于对金银花中有效成分提取,对其中黄酮类成分保持较高的吸附率,同时MNP-NH_2的循环使用与再生性良好,为复杂中药及天然药物有效成分提取应用提供新的研究思路。

Objective To synthesize amino-modified Fe3 O4 nanoparticles（MNP-NH2） and study the adsorption of flavonoids and organic acids by MNP-NH2.Methods MNP-NH2 were synthesized and characterized by transmission electron microscopy,scanning electron microscopy,Fourier transform infrared spectroscopy,and vibrating sample magnetometer analysis; The adsorption rule of MNP-NH2 was discussed by studying the adsorption properties of 12 monomers.The adsorption properties of MNP-NH2 were assessed under conditions of different ultrasonic time,temperature,ionic strength,and p H.The final elution conditions were determined by L9（34） orthogonal test and the recycling performance was also considered.Results MNP-NH2 synthesized in this study have stable structure,uniform distribution,and good magnetic properties.Adsorption of 12 monomers by MNP-NH2 showed that the mechanism of adsorption was related to the number of ortho-phenolic hydroxyl groups.Ions concentration and temperature had little effect on adsorption for different compounds except p H.The optimized adsorption conditions were extraction for 40 min at 30 ℃ and the final elution conditions were determined to be 5 m L of 20% glacialacetic acid（methanol-water 60∶40） and ultrasonication for 40 min.Conclusion MNP-NH2 can be utilized to extract the effective components of Lonicerae Japonicae Flos and maintain a high adsorption rate of flavonoids.Moreover,MNP-NH2 had great recycling and reproducibility,providing new ideas for the utilization of extracting chemical compounds from complex traditional Chinese medicine and natural medicines.