Preparation and application of streptavidin magnetic particles  

作　　者：ZHANG ZhiFeng ZHU HongLi TANG YiTong CUI Ting GENG TingTing CHEN Chao CUI YaLi 

机构地区：[1]Biochip Research and Development Center,Northwest University(National Engineering Research Center for Miniaturized Detec-tion System),Xi’an 710069,China [2]Shaanxi Lifegen Co.,Ltd.,Xi’an 710069,China

出　　处：《Science China Chemistry》2007年第1期127-134,共8页中国科学（化学英文版）

基　　金：the National Natural Science Foundation of China(Grant No.20273050);the National High Technology Research and Development Programof China(Grant No.2005AA205220)

摘　　要：Two kinds of streptavidin magnetic particles,namely streptavidin GoldMag particles and streptavidin amino terminal particles were prepared by the methods of physical adsorption and covalent interaction respectively.The streptavidin coated on magnetic particle surface,crucial to many applications,was greatly influenced by the choice of the different buffer.Compared with DynalbeadsM-270 streptavidin, the binding capacity for biotin of different streptavidin magnetic particles was determined by enzyme inhibition method,and the coupling capacity and activity of biotinylated oligonucleotide on their sur- face were also analyzed.The results indicated that the streptavidin GoldMag particle prepared by physical adsorption was stable in STE(NaCl-Tris-EDTA)buffer that was frequently used in nucleic acid hybridization and detection.The streptavidin amino terminal particles prepared by covalent interaction could be used both in STE buffer and PBS(phosphate buffered saline)buffer.The biotin binding ca- pacity for 1 mg of streptavidin GoldMag particles and streptavidin amino terminal particles was 4950 and 5115 pmol respectively.The capacity of biotinylated oligonucleotide(24 bp)coupled on 1 mg of GoldMag and amino terminal magnetic particles was 2839 and 2978 pmol separately.These data were about 6-7 times higher than those of DynabeadsM-270 streptavidin.The hybridization results with FITC-labeled complementary probe on magnetic particle surface demonstrated that the oligonucleotide coupled on streptavidin magnetic particles had high biological activity.Two kinds of streptavidin magnetic particles, namely streptavidin GoldMag particles and streptavidin amino terminal particles were prepared by the methods of physical adsorption and covalent interaction respectively. The streptavidin coated on magnetic particle surface, crucial to many applications, was greatly influenced by the choice of the different buffer. Compared with Dynalbeads?M-270 streptavidin, the binding capacity for biotin of different streptavidin magnetic particles was determined by enzyme inhibition method, and the coupling capacity and activity of biotinylated oligonucleotide on their surface were also analyzed. The results indicated that the streptavidin GoldMag particle prepared by physical adsorption was stable in STE (NaCl-Tris-EDTA) buffer that was frequently used in nucleic acid hybridization and detection. The streptavidin amino terminal particles prepared by covalent interaction could be used both in STE buffer and PBS (phosphate buffered saline) buffer. The biotin binding capacity for 1 mg of streptavidin GoldMag particles and streptavidin amino terminal particles was 4950 and 5115 pmol respectively. The capacity of biotinylated oligonucleotide (24 bp) coupled on 1 mg of GoldMag and amino terminal magnetic particles was 2839 and 2978 pmol separately. These data were about 6–7 times higher than those of Dynabeads?M-270 streptavidin. The hybridization results with FITC-labeled complementary probe on magnetic particle surface demonstrated that the oligonucleotide coupled on streptavidin magnetic particles had high biological activity.

关 键 词：STREPTAVIDIN magnetic PARTICLES PREPARATION application 

分 类 号：Q939.9[生物学—微生物学]