Purification Synephrine Hydrochloride From The Extracts Of Citus Aurantium With The Graphene Oxide Molecularly Imprinted Membrane Technology

Treating with natural herbal has been populared with most people for a long time.However,due to its complex composition,it's important and difficult for many scientific research projects to extract active ingredient efficiently.As we can see,it has a great meaning to extract active ingredient of natural herbal efficiently for scientific research.Current advanced separating and purifying technology is membrane separation,and molecularly imprinted membrane(MIM)which is one kind of the membrane separation,is the most mature and advanced technology all over the world up to now.But it also has its own shortcomings,such as poor mechanical properties,which seriously affects the promotion and applied of MIM.Graphene oxide(GO),a derivative of carbon material,can disperse well in water because of its unique structure of two-dimensional single layer of carbon atoms and containing a large number of hydrophilic,hydroxyl and carboxyl groups.What's more,due to the large surface area of GO,it's convenient for other nanometer materials to disperse and adhere on it when they combine each other.In this study,molecularly imprinting membrane technology was combined with graphene oxide to prepare molecular imprinted membrane whose template molecule was synephrine hydrochloride and graphene oxide was added into the MIM to improve its mechanical properties as well as be applied in aqueous systems efficiently.A high degree oxidaton of graphene oxide was prepared by the improved Hummers easily and efficiently.Graphite as raw materials,sulfuric acid(98%),potassium permanganate and sodium nitrate as initial oxide oxidant,hydrogen peroxide as deep oxidation are used to modified graphite.Transmission electron microscopy(TEM),X-ray diffraction(XRD),Raman spectroscopy(RS)and infrared spectroscopy(IR)were used to characterize the graphene oxide.The characterization results show that the graphene oxide was successfully prepared and its oxidation degree was very high,the specific surface area was very large.Self-assembled cross-linked polymeric radical approach as polymerization method,synephrine hydrochloride as template molecule,acrylamide as functionalmonomer,homemade ionic liquids([Bmin] Br)and water as solvent,ammonium persulfate as initiator,N,N'-methylene-bis-acrylamide(MBA)as crosslinking agent,graphene oxide(GO)as the additive,N,N,N,N-tetramethylethylenediamine as catalyst were mixed together to successfully prepared the molecular imprinted membrane(MIM)which can be applied in aqueous system.And the effects of different amount of graphene oxide to MIM's mechanical,adsorption capacity and adsorption selectivity were analysed.Freundlich and Langmuir curve were used to study the binding characteristics of MIM to the template molecule,at the same time,Elcotromechanical Universal Testing Machine(EUTM)was used to test GO-MIM's mechanical ability.Successfully synthetizing GO-MIM layed the foundation of its promotion.