硅烷法固定ssDNA制作的压电式DNA传感器

利用硅烷法将ssDNA固化T方向切割、3.58MHz和10MHz石英晶体金电极上,构建了压电DNA传感器,建立了快速检测葡萄球菌肠毒素B(SEB)基因的方法。优化了固定SEB基因的条件,并用动态法、静态法和斑点杂交法进行了固化效果观察。结果表明:该传感器2h后,有较好响应;对不同长度DNA探针固化效果进行比较,169bp(即169个碱基)SEB探针固定和杂交效果较好;利用0.5mol/LNaOH进行电极洗脱,时间为45min,电极可以再生,且传感器可以重复使用3次;利用1.2mol/LNaOH和1.2mol/LHCl洗涤电极,该电极可多次再利用;固化好的电极于4℃条件下可以保存三周之久。

Piezoelectric DNA sensor employing APTES immoboilized ssDNA method

?A rapid method has been developed to monitor Staphylococcal enterotoxin B(SEB) gene by using piezoeletric DNA sensor system.AT cut crystals,with a based resonant frequency of 3.58?MHz and 10?MHz,were modified by 3 aminopropyltriethoxysilane(3 APTES) treatment and then single stranded SEB gene probe was electro blotted onto the surface of crystal electrodes.The optimization condition of immobilization for piezoeletric DNA sensor was researched.Immobililzed efficiency was observed by active methods, passive methods and dot hybridization method.There is better response of the piezoelectric DNA sensor after DNA hybridization for 2?h.Hybridization effect of 169?bp SEB gene probe was better comparing with the other different length of SEB gene probe. The sensor could be repeatedly used,the complementary ssDNA of the SEB DNA probe could be removed from the crystal by washing with 0.5?mol/L NaOH denaturant.After the hybridized electrode was immersed in 1.2?mol/L NaOH and then 1.2?mol/L HCl,all substances could be removed from the crystal surface,and the quartz crystal could be reused for many times.The 3 APTES coated ssDNA electrode was stable for over three weeks when stored at 4?℃.