为了克服目前生物芯片荧光检测方法中诸如系统结构复杂、检测速度慢、灵敏度低、成本高等缺点,提出了一种新型生物芯片荧光检测方法——线扫描准共焦荧光成像法,并搭建了初步原理性装置。用线扫描代替共聚焦中的点扫描,将二维扫描变为一维扫描,在保持高灵敏度的同时,增加了探测速度,简化了系统,降低了成本。为了验证方法的可行性,使用搭建的原理性装置对手工点样的低密度DNA生物芯片进行了荧光成像检测。实验结果显示,系统的空间分辨率〈18μm,在使用像素平均法降噪后,测量浓度为0.03μmol/l的探针溶液所得信噪比为5.5×10^2。这项技术综合了面成像检测方法的低成本、结构简单的优势和点共焦方法具有的高分辨率的优点,适合在实验室中对生物芯片进行检测研究。
In order to overcome the drawbacks of traditional fluorescence imaging methods and to achieve a biochip fluorescence imaging technique with high sensitivity and low costs,a novel biochip fluorescence imaging technique,line-scanning quasi-confocal fluorescence imaging method,was proposed and a prototype system was set up.By using a line scanning to replace a point scanning and changing the 2-D scan into the 1-D scan,the system can provide higher sensing speeds,simpler structures and lower costs while maintaining the high sensitivity.To verify the feasibility of the method,the prototype system was used to sense the fluorescence image of a manually prepared low density DNA microarray.Experimental results indicate that the spatial resolution of the system is better than 18 μm,and the Signal to Noise Ratio(SNR) of the system is 5.5×10^2 by using the pixel-averaging method to reduce noises.By combining the low cost and simple structure of the area imaging method with the high sensitivity of the confocal point-scanning imaging method,the technique is suitable for the biochip study in laboratories.