DNA分析仪的研制及性能考查

Development and performance investigation of DNA analyzer

自行研制DNA分析仪,采用毛细管电泳分离DNA片段,激光诱导荧光技术进行检测。检测部分设计为共焦光路,488 nm的Ar+激光器激发DNA片段上标记的荧光染料,发射的荧光信号由光电倍增管收集检测,激发光路和收集光路可三维调节。优化毛细管电泳-激光诱导荧光检测装置的设计和分析参数,实现了高分辨率、高灵敏度的DNA样品分析。实验结果表明,对于分析标准DNA样品pGEM-3Zf(+)/HaeⅢMarkers和pBR322 DNA/HaeⅢMarker,标记的2种荧光染料分别为Thi- azole Orange(TO)和SYBR GreenⅠ,本分析仪均获得了高信噪比的毛细管电泳图谱,较好地实现了单碱基分辨,检测灵敏度为2.4×10^(-11)mol/L。

A DNA analyzer was developed. Capillary electrophoresis （CE） was adopted to separate different fragments of DNA with laser induced fluorescence detection （LIFD） system. LIFD is designed according to the confocal theory. The fluorescence dyes on the DNA fragments are excited by 488 nm Ar ＋ Laser and the fluorescence signal is collected by photomuhiplier tube （PMT）. The exciting and collecting light path can be adjusted in 3-D. The high resolution and high sensitivity analysis of DNA sample is realized. The standard samples pGEM-3Zf（ ＋ ）/Hae III Markers and pBR322 DNA/Hae Ⅲ Marker are analyzed using CE. Two fluorescence dyes Thiazole Orange （TO） and SYBR Green Ⅰ are compared and the high resolution CE patterns are both obtained. The single base pair can be distinguished in CE patterns. The detection sensitivity is 2.4 × 10^-11 moL/L.