多孔磁性硅胶微球的制备及其在基因组脱氧核糖核酸提取中的应用

采用模板法制备了多孔磁性硅胶微球,用于生物样品中基因组脱氧核糖核酸(DNA)的分离纯化。以球形和无定型硅胶为对照,考察了吸附液组成和洗脱时间等实验参数对小牛胸腺基因组DNA在磁性硅胶固相载体上的提取回收率的影响。实验结果表明:20%(W/V)聚乙二醇和2 mol/L氯化钠,洗脱10 m in,DNA的回收率可达80%;采用简单的细胞裂解体系和合适的吸附液组成,磁性微球应用于酿酒酵母中基因组DNA的提取,得到了平均长度约为5 kb、A260/A280大于1.77的高纯度DNA片段。

Preparation of Porous Magnetic Silica Microspheres and Their Application for Genomic Deoxyribonucleic Acid Extraction

Porous magnetic silica microspheres with high magnetization,uniform particle size distribution and large surface area were prepared by a polymer templated method.The microspheres were used as solid-phase adsorbents for extraction of genomic deoxyribonucleic acid(DNA) from biological samples.Effects of experimental parameters including composition of capturing buffer and elution time on the yields of DNA isolated(using) the magnetic microspheres were examined and compared with those obtained with spherical and irregular silica particles.Results show that recovery yields of DNA up to 80% can be obtained on solid-phase adsorbents with a capturing buffer composed of 20% polyethylene glycol(PEG) and 2 mol/L NaCl and elution time of 10 min.The magnetic microspheres and silica particles were applied for isolation of genomic DNA from(Saccharomyces)cerevisiae after the cells were lysed and the genomic DNA fragments of about 5 kb were(obtained) with the A_(260)/A_(280) values in the range of 1.77-1.82.The magnetic microspheres are comparable with the silica particles in terms of yield and purity of DNA isolated.