氨基酸-纤维素复合材料的模拟酶对邻苯二甲酸酯塑化剂的降解

The Amino Acids and Cellulose Conjugation Based Enzyme Mimics for Degradation of Phthalic Acid Esters

以微晶纤维素为骨架材料,通过高碘酸钠氧化方法将其氧化为双醛基纤维素,再通过席夫碱反应连接活性氨基酸(丝氨酸、组氨酸、天冬氨酸),构建氨基酸-纤维素复合材料模拟酶,并利用红外光谱、X-射线衍射和扫描电子显微镜对模拟酶进行表征,证实成功制备氨基酸-纤维素复合材料模拟酶。通过检测对邻苯二甲酸二(2-乙基己)酯[di(2-ethylhexyl)phthalate,DEHP]的降解,发现在pH 9.0,温度40℃条件下48 h可以有效降解60.1%的DEHP;进一步比较对另外两种塑化剂邻苯二甲酸二甲酯(dimethyl phthalate,DMP)和邻苯二甲酸二丁酯(dibutyl phthalate,DBP)的降解效果,结果表明,模拟酶对DEHP降解率最高,其次是DBP和DMP。

An enzyme mimics was designed by combination with amino acids and microcrystalline cellulose.The microcrystalline cellulose was first functionalized by the NaIO4 oxidation method to form aldehyde groups and then conjugated with amino acids(serine,histidine and aspartate)via Schiff-base reaction.The enzyme mimics were characterized by Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XRD)and scanning electron microscopy(SEM).The enzyme mimics showed good performance in degradation of di(2-ethylhexyl)phthalate(DEHP),degraded as high as 60.1%of the initial DEHP within 48 h at pH 9.0 in 40℃.Besides,DEHP degradation efficiency was observed to be higher than those of dibutyl phthalate(DBP)and dimethyl phthalate(DMP)under optimal conditions.