基于微细加工技术的高精度荧光检测生物芯片

High Precision Fluorescent Detection Bio-Chip Based on the Microfabrication Technique

荧光检测生物芯片在生命科学研究及诸多相关领域已经得到了广泛应用。利用荧光修饰核酸探针可以在液相态中检测到c-fos mRNA致癌基因信息或病毒性核糖核酸(RNA)。通过微细加工技术分别制造了变深度微沟道和变宽度微沟道,目的是找到微生物荧光检测芯片中的最佳检测宽度和深度,并对检测装置中光学滤波片进行了优化。芯片采用最优尺寸和装置采用优化过的荧光滤波片,不仅大幅缩短了检测时间,节省了荧光探针试剂,而且还提高了芯片荧光检测灵敏度。实验结果表明:当荧光检测系统的微沟道深度为500μm、宽度为200μm,并使用(480±15)nm的带通滤波片时,荧光修饰核酸探针的探测灵敏度从通常的20 fmol(即2×10-14 mol)减低到50 amol(即5×10-17 mol),提高了约400倍,大大提高了系统的检测精度。

The fluorescent detection has been widely applied in life science and other related fields.By using the fluorescent mRNA probe,the cancer gene such as c-fos mRNA or virus RNA can be detected in the liquid phase.In order to find out the optimum detection depth and width in the microbial fluorescence detection chip,the micro channel with changeable depth and micro channel with changeable width were fabricated by the microfabrication technology respectively,and the optical filter of the detection setup for the fluorescent detection was optimized.Using the chip of optimum size and optimized fluorescence filter,a lot of detection time and fluorescent probe reagent are saved,the fluorescence detection sensitivity of the fluid chip is improved.The experiment result shows that the fluorescent detection system sensitivity is greatly improved by using a（480±15）nm band-pass filter and the micro channel with500μm in depth and200μm in width.The detection sensitivity resolution of the RNA molecule can reach 50 amol（50×10-18 mol）level,which is improved 400 times,compared with the normal level of 20 fmol（20×10-15 mol）.