Preparation And Adsorption Properties Of Aristolochic Acid ? Molecularly Imprinted Material

Aristolochic acid I(AAI)is a nitrophenicarboxylic acid compound naturally produced in aristolochiaceae plants,which,has attracted many attentions due to its toxicity to the kidneys.The study on the effective separation and purification of aristolochic acid I in traditional Chinese medicine plants is of great practical significance to reduce the toxicity of traditional Chinese medicine plants.In this paper,a simple,direct and rapid method for specific adsorption of aristolochic acid I in Chinese medicinal plants was established.The MIPs were prepared by sol-gel molecular imprinting method with 1,10-phenanthroline-4-carboxylic acid as dummy template,(3-aminopropyl)triethoxysilane as functional monomer,tetraethoxysilane as crosslinker and hydrochloric acid as catalyst,which were applied to selectively remove aristolochic acid I from kaempfer dutchmanspipe root extract.The morphology,structure and properties of MIPs were analyzed by fourier transform infrared spectroscopy,scanning electron microscope and nitrogen adsorption/desorption analysis.The adsorption isotherm experiment showed MIPs had a high adsorption capacity to aristolochic acid I,Qmax was 8.12 mg g-1,while the Qmax of NIPs was only 1.92 mg g-1.The adsorption isotherm fitting results were consistent with the Langmuir isotherm model,indicating that MIPs imprinting sites were uniformly distributed.The adsorption kinetics showed that MIPs had fast binding kinetics,and the adsorption capacity within 1 min could reach 61.3%of the Qmax.The adsorption kinetics fitting results were consistent with Elovich kinetic model,indicating that the adsorption of aristolochic acid I by MIPs was heterogeneous.In addition,according to the fitting results of intra-particle diflfusion dynamics model,it is known that the adsorption process of MIPs is affected by multiple diffusion mechanisms.Selective experiments showed that MIPs for AAI exhibited superior specific recognition ability compared with AAII,2-nitroterephthalic acid,benzoic acid and p-nitrophenol,and the imprinting factor(IF)reached to 4.23,which is significantly higher than the other three kinds of structure analogue.In the actual sample experiment,MIPs were able to remove aristolochic acid I below the HPLC limit of detection from Kaempfer dutchmanspipe root extract.