| Naringin,a natural flavonoid compound,widely exists in nature with cis-diol structure.Research shows that it possesses excellent biological activity,pharmacological effects and application value in the food industry.Currently,many methods for extracting NRG at home and abroad,although each has its advantages,there are still shortcomings that cannot meet the requirements of efficient NRG separation and purification.Therefore,exploring a new approach with independent intellectual property rights for selectively separating and purifying NRG and improving the yield of NRG in the product to make it be effectively and reasonably appliced presents extremely important scientific,economic,and social significance.In this paper,we designed and synthesized new Pickering particles,shuch as microporous organic polymers CDPs with β-cyclodextrin as the unit monomer,covalent organic frameworks COFs and RAFT functionalized cellulose nanocrystals,and adjusted their type,structure and functionalization to regulate the stability of emulsion droplets and explored the stability mechanism of emulison,and constructed flexible boronate affinity copolymers,hollow boronate affinity microcapsules and porous boronate affinity molecularly imprinted polymer microspheres adsorbents via emulsion interfacial polymerization droplet reactor.The morphology,structure,composition,and other properties of boronate affinity adsorbent materials were investigated using rational characterization methods.Utilizing the characteristic that the boric acid group in the phenylboronic acid monomer can form a reversible five/six-membered cyclic ester with cis-diols,NRG can be rapidly adsorption/desorption.And the selective separation and purification ability of NRG was evaluated through batch static adsorption experiments.The main contents are as follows:(1)Research on the construction of boronate affinity macroporous copolymers using microporous organic polymer CDPs as Pickering particles by self assembly at the emulison interface and their performance for the separation and purification of NRG.Firstly,microporous organic polymers CDPs were prepared with β-cyclodextrin(β-CD)as the unit monomer,followed by CDPs were used as emulsifiers to form the O/W Pickering emulsion and self-assembled with boric acid functionalized amantadine(Ad)derivative ABIB-BA at the emulsion interface.Boric acid functionalized copolymer(BCDPs-CPs-2)with cross-linked hydrogen bond network was prepared by emuslion interfacial polymerization employing MMP as aqueous phase and MEA as oil phase,and was utilized to separate and purify NRG.The steady macroporous structure and shape memory ability effectively improved the regeneration performance of BCDPs-CPs-2 under actual extraction conditions.Static adsorption experiments demonstrated that the adsorption of NRG by BCDPs-CPs-2 followed a pseudo-second-order kinetic model,reaching adsorption saturation within 360 minutes;the equilibrium adsorption capacity at 298 K was 3.14μmol/g;after five adsorption-desorption adsorption cycles,BCDPs-CPs-2 still maintained 94.66%of the initial adsorption capacity value;the purity of purified NRG is about 96.67%.(2)Research on the construction of boronate affinity microcapsules by two step emulsion interfacial polymerization of Pickering particles with covalent organic framework(COFs)and their performance for the separation and purification of NRG.Firstly,we designed and synthesized covalent organic frameworks(TAPB-BTCA-BPTA COFs)with TAPB,BTCA and BPTA as skeleton monomers,and stabilized W/O Pickering emulsion.Secondly,through the second emulsion interfacial polymerization,COFs competitors were introduced into emulsion system,and interfacial polymerization was carried out on the surface of droplets to successfully prepare microencapsulated(TAPB-BTCA-BPTA MC)with double COF shell.Using it as an anchoring device,boron affinity microcapsules BA-TAPB-BTCA-BPTA MC were prepared by modifying N3-PBA via azide-alkyne click reaction.The characterization results displayed that the structure was complete,the size was uniform,and the surface showed a COF shell layer with excellent mechanical properties.Based on the hollow structure and high-density boric acid recognition sites on the surface,the static adsorption experiment results inllustrated that the adsorption mechanism of BA-TAPB-BTCA-BPTA MC for NRG was chemical adsorption,reaching an adsorption equilibrium within 270 minutes;at 308 K,the adsorption equilibrium of BA-TAPB-BTCA-BPTA MC for NRG was better fitted by Langmuir equation and the equilibrium adsorption capacity was 38.12 μmol/g,resulting in better p H responsive adsorption performance and adsorption rate for NRG.(3)Research on the construction of porous boronate affinity imprinted microspheres by one step emulsion interfacial polymerization of Pickering particles using RAFT functionalized CNCs and their performance for separation and purification of NRG.Firstly,we prepared a RAFT functionalized CNCs(CNC@DDMAT)and then employed CNCs@DDMAT as collide particles to stable Pickering O/W emulsion,where deionized water and toluene were as the water phase and oil phase,respectively.Among them,porous boronate affinity imprinted polymer microspheres(BA-HPMIPs)were successfully fabricated by combining Pickering emulsion method with molecular imprinting technology,utilizing NRG as template molecule,APBA with low p Ka value as functional monomer,and EGDMA as cross-linking agent,and used BA-HPMIPs for selective enrichment of NRG.The adsorption kinetics,equilibrium,selectivity,regeneration performance,and actual sample purification were evaluated through static adsorption experiments.The results indicated that the adsorption of NRG by BA-HPMIPs reached equilibrium within 360 min;Langmuir model preferably described the adsorption equilibrium process,with an equilibrium adsorption capacity of118.32 μ mol/g at 308 K;selective test revealed imprinting factor IF=4.46;BA-HPMIPs also owned favourable regeneration performance;the purity of purified NRG could reach 96.75%. |
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