生物芯片表面氨基硅烷化修饰

Amino Silanization Modification of Biochip Surface

本文以无水乙醇为溶剂、3-氨基丙基三乙氧基硅烷(APTES)为修饰试剂、醋酸为催化剂,采用浸泡法,对生物芯片玻璃基片表面进行了氨基硅烷化修饰,得到了一种基片表面氨基修饰的制备方法。着重研究了制备过程中浸泡时间、APTES的浓度、酸处理的时间和羟基化的时间对基片噪声的影响。通过对以上工艺参数的逐步优化,基片噪声逐渐减小,最小值为193。通过对最佳修饰条件下得到的基片进行DNA点样和杂交测试可知,此方法制备得到的基片能够有效结合基因探针,且杂交清洗后信号强度可达17000以上,信噪比在110以上。由X射线光电子能谱分析可知,采用浸泡法可以获得表面氨基修饰的生物芯片基片。最后通过对修饰前后基片透过率的比较可知,修饰过程对透过率影响很小,且透过率在91%以上,从而保证了后续杂交信号与微阵列噪声检测的准确性。

Biochips with amino groups on the substrate surface were prepared through a special immersion method using absolute ethanol as the solvent, 3-aminopropyltriethoxysilane （APTES） as the modifying agent and acetic acid as the catalyst. The impacts of different process parameters in the preparation process on the substrate noise were mainly studied, including soaking time, APTES concentration, acid treatment time and hydroxylation time. Through stage-by-stage optimization of the process parameters above, the substrate noise decreased effectively, with the minimum value of 193 obtained. The results of the spotting test and hybridization test of the substrates pre-treated under the optimum modification condition show that the substrate prepared by this method could effectively connect the gene probe, with the hybridization signal intensity after cleaning up to 17 000 and the signal-to-noise ratio above 110. The X-ray photoelectron spectroscopy （XPS） analysis indicates a successful integration of amino group onto the surface of biochip substrate after modification. It was found that the modification process had little effect on the transmittance of substrates, all kept above 91%, and thus ensured the accuracy of the hybridization signal and microarray noise detection followed.