摘要：
Silybin, a hepatoprotective active natural ingredient, was used as the template, methyl acrylic acid (MAA) as the functional monomer, n-isopropyl acrylamide (NIPAm) as the thermal response monomer, magnetic core Fe3O4@CS@APTES@BiBB coated by biocompatible chitosan as the carrier, and a kind of silybin molecularly imprinted materials (MMIPs) based on pH/temperature dual responses were prepared by electron transfer activation regenerative catalyst atom transfer radical polymerization (ARGET ATRP). The synthesized material was characterized by FT-IR, TGA, SEM, XRD, VSM, and XPS, and the loading behavior of silybin in MMIPs could be explained by the pseudo-second-order kinetic model. The selectivity factor alpha (2.636) and the relative selectivity factor beta (2.468) indicated MMIPs had good specific recognition ability for silybin. In addition, a series of experimental data displayed MMIPs had many other excellent characteristics such as adsorption property, swelling performance, biocompatibility, degradability, stability, reproducibility and so on. The cumulative release rates of MMIPs could reach 29%, 23% and 25% in the media of pH 1.0, 7.4 and 8.2 at 37.5 degrees C, resepectively, and when the temperature was raised to 43 degrees C, the release rate of MMIPs in solution (pH 7.4) reached 49%, which indicated that the carrier material had good pH/temperature dual responses.
通讯机构：
[Tan, Ni] U;Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.
关键词：
Hollow;Magnetic;Molecularly imprinted polymer;Silybin;Sustained released agent
摘要：
In this study, a new type of drug delivery carrier, the hollow magnetic silybin molecularly imprinted polymer (HMMIP) with a unique core-shell structure where the hollow magnetic core Fe3O4 was wrapped by mesoporous silica and imprinted layer, was prepared from methacrylic acid (MAA, functional monomer), ethylene glycol dimethacrylate (EGDMA, cross-linker), and silybin (a drug template) by reverse atom radical transfer polymerization method (RATRP), and characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffractometer (XRD), vibrating sample magnetometer (VSM), thermo-gravimetric analysis (TGA), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller analysis (BET). Its adsorption performance was evaluated by the isotherm/kinetic models and the selectivity for silybin with 15.40mgg(-1) of adsorption capacity and 2.13 of selectivity factor alpha, respectively. The drug release experiment showed the prepared polymer had the properties of silybin sustained release agent, because it could last to release silybin for 36h in the medium of pH 2.0 at physiological temperature. In addition, the resuability experiment indicated the imprinted material had the good stability and reproducibility. So HMMIP should be of the potential value applied in drug delivery in the future.
摘要：
以护肝活性天然产物水飞蓟宾(silybin)为模板分子,甲基丙烯酸(methacrylic,MAA)为功能单体,N-异丙基丙烯酰胺(N-isopropyl acrylamide,NIPAm)为热响应单体,生物相容性壳聚糖包裹Fe3 O4磁核作为载体,运用电子转移活化再生催化剂原子转移自由基聚合(activator regenerated by electron transfer atom transfer rad-ical polymerization,ARGET ATRP)制备水飞蓟宾磁性分子印迹聚合物(molecularly imprinted polymers,MMIPs),并运用傅里叶变换红外光谱(fourier transform infrared spectroscopy,FT-IR)、(thermogravimetric analysis,TGA)、(scanning electron microscope,SEM)和(X-ray diffraction,XRD)对合成的磁性印迹材料进行了表征.MMIPs对水飞蓟宾的动态吸附行为可以通过准二级动力学模型解释说明.MMIP s的印迹因子γ为3.20、选择性因子α(2.636)及相对选择性因子β(2.468),反映了所合成的印迹材料对水飞蓟宾具有良好的特异性识别能力和选择性吸附能力.另外,通过八次循环利用实验,发现MMIP s的吸附量仅减少22％,这说明了所制备的印迹材料尚具有良好的稳定性.
期刊：
Journal of Polymer Research,2018年25(7):1-14 ISSN：1022-9760
通讯作者：
Tan, Ni
作者机构：
[Han, Jingwen; Ji, Kang; Tan, Ni; He, Dianxiong; Gao, Yang; Yan, Xueming; Wang, Juan] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Tan, Ni] U;Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Hunan, Peoples R China.
关键词：
Silybin;Magnetic molecularly imprinted polymer;Computer simulation;Selectivity recognition;Reverse atom transfer radical precipitation polymerization
摘要：
Using hepatoprotective component silybin as the template, MAA as the functional monomer, EGDMA as the cross linker, acetonitrile as the solvent, and Fe3O4 as the magnetic substrate, the silybin magnetic molecularly imprinted polymer(S-MIP) was successfully prepared by the reverse atom transfer radical precipitation polymerization(RATRP), and non-ion imprinted polymer(NIP) was also synthesized by the same procedure only in the absence of silybin. On the basis of computer simulation and L9(34) orthogonal array design matrix, the optimal preparation conditions were finally obtained as follows that the molar ratio of silybin, MAA, and EGDMA was 1:5:60. The prepared materials were respectively characterized by SEM, XRD, FT-IR, VSM and TGA, and the kinetic analyses explored that the adsorption process of S-MIP was better describled by the pseudo-second order kinetic equation, meanwhile, scatchard analysis illustrated that the heterogeneous binding sites existed in S-MIP. Both the selectivity factor α (2.232) and the relative selectivity factor β (2.201) of S-MIP showed the aim material had the excellent specific recognition capacity and selection adsorption property to silybin. Additionally, the recycling reuse experiments explored S-MIP was of a good stability and could be used repeatedly at least five times with only 15.8% decrease of adsorption capacity when applied in the fifth experiment, and the evaluation experiments by HPLC for silybin extraction from the medicinal herb milk thistle seeds indicated that S-MIP had the potential application in separating the natural hepatoprotective component silybin from the herbal plants.
摘要：
Fusarium sp. #ZZF51 was chemically treated by cetyltrimethyl ammonium bromide to explore its potential for the removal of uranium(VI). The experimental results showed that the biosorption capacity and the removal efficiency for the modified mycelium under optimal conditions were 400.10 mg g−1 and 96.02 %, respectively, which were more than those of the native biomass (21.42 mg g−1 and 61.89 %). Lagergren’s pseudo-second-order kinetic model and Langumir isotherm model showed the better agreement with the experimental data. SEM experiment indicated the mycelium could provide ready access and rich surface area for uranium binding, and FTIR analysis revealed that hydroxyl, carbonyl, especially for nitrogen groups played important roles in biosorption.
摘要：
Fusarium sp. #ZZF51, marine-derived mangrove endophytic fungus, was chemically modified by poly(amic acid) to enhance its potential of uranium(VI) biosorption in aqueous solution. Compared with uranium(VI) removal of the pristine biomass, the maximum uranium(VI) adsorption capacity of the modified biomass increased 9.5-fold under the optimal condition of pH 5.0, S/L 0.4, and equilibrium time 180 min. Kinetic study showed that the process follows the pseudo-second-order kinetic model, which indicates that chemical reaction controls the adsorption rate. The thermodynamic experimental data fit well with Langumir, Freundlich, and Temkin isotherms, and their R 2 values are 0.954, 0.963, and 0.986, respectively. FTIR spectroscopic analysis of the native, modified, and uranium-loaded biomass demonstrated the involvement of carboxyl, amide, and hydroxyl groups on the surface of fungus Fusarium sp. #ZZF51 cell wall in the adsorption of uranium(VI).
摘要：
Fusarium sp. #ZZF51, mangrove endophytic fungus originated from South China Sea coast, was chemically modified by formaldehyde, methanol and acetic acid to enhance its affinity of uranium(VI) from waste water. The influencing factors about uranium(VI) adsorption such as contact time, solution pH, the ratio of solid/liquid (S/L) and initial uranium(VI) concentration were investigated, and the suitable adsorption isotherm and kinetic models were determined. In addition, the biosorption mechanism was also discussed by FTIR analysis. Experimental results show that the maximum biosorption capacity of formaldehyde-treated biomass for uranium(VI) at the optimized condition of pH 6.0, S/L 0.6 and equilibrium time 90 min is 318.04 mg g−1, and those of methanol-treated and HAc-treated biomass are 311.95 and 351.67 mg g−1 at the same pH and S/L values but different equilibrium time of 60 and 90 min, respectively. Thus the maximum biosorption capacity of the three kind of modified biomass have greatly surpassed that of the raw biomass (21.42 mg g−1). The study of kinetic exhibits a high level of compliance with the Lagergren’s pseudo-second-order kinetic models. Langumir and Freundlich models have proved to be well able to explain the sorption equilibrium with the satisfactory correlation coefficients higher than 0.96. FTIR analysis reveals that the carboxyl, amino and hydroxyl groups on the cell wall of Fusarium sp. #ZZF51 play an important role in uranium(VI) biosorption process.
