双甘膦修饰磁性四氧化三铁纳米微球吸附DNA的研究

摘要

PMIDA Modified magnetic iron oxide nanospheres,which were chelated with Zn2+,were obtained.The effects of adsorption conditions including adsorption solution pH value,ionic strength,adsorption time and adsorption temperature on DNA adsorption were investigated.The results showed that the adsorption rate and the adsorption capacity could reach up to 80% and 21 mg·g-1,respectively,when the adsorbent dosage was 10 mg,the solution pH value was 5.0,ionic strength (NaCl concentration) was 2.0 mol·L-1,adsorption time was 20 min and adsorption temperature was 35 ℃.The adsorbed DNA could be completely eluted from the magentic nanospheres by 3.5% ammonia solution.When the modified microspheres were applied to extracting DNA from corn flour,the results were satisfactory with high-purified DNA.%用双甘膦(PMIDA)修饰磁性四氧化三铁纳米微球(MNP)并负载Zn2+制得了PMIDA-Zn2+修饰磁性微球吸附剂.考察了吸附溶液的pH值、离子强度、吸附时间、吸附温度等因素对DNA吸附的影响.结果表明,当吸附剂用量为10 mg、pH值为5.0、离子强度(NaCl浓度)为2.0 mol·L-1、吸附时间为20 min、吸附温度为35℃时,吸附率可达80％,吸附容量为21 mg·g-1.被吸附的DNA用3.5％的氨水能完全洗脱.将PMIDA-Zn2+修饰磁性微球用于玉米DNA的提取,所得DNA纯度较高,效果令人满意.