一种双通道荧光扫描同步探测系统的设计

Design of dual-channel fluorescence synchronous detection system

目的:设计一种双通道荧光扫描同步探测系统,以实现对活/死菌的快速检测。方法:基于双色荧光染色技术,针对检测对象的荧光特性设计双光源同步激发的荧光探测系统;采用空间错位的共焦设计方法,解决双光源同步激发探测中互相干扰的问题;通过MATLAB编程编写阈值分割结合边缘检测的目标提取算法实现对细菌荧光信号的准确提取与计数。采用荧光探测性能测试、荧光显微镜对照试验和活/死菌混合样本扫描检测对系统的性能进行验证。结果:该系统能实现红绿荧光信号的同步扫描探测;与荧光显微镜检测获得的图像特征完全匹配,且扫描检测视野远大于荧光显微镜检测视野;测得的活/死菌比例值与已知样本的活菌含量的相关程度高(R2=0.9708)。结论:该系统可快速完成对活/死菌的准确识别和定量分析,在微生物活性检测和定量分析领域具有广阔的应用前景。

Objective To design a dual-channel fluorescence synchronous detection system to rapidly detect live and dead bacteria.Methods A fluorescence detection system was designed based on the two-color fluorescence staining technology to synchronize the excitation of two light sources according to the fluorescence characteristics of the detection object;confocal design method for misalignment was used to solve the problem of mutual interference in the synchronous excitation detection of dual light sources;the target extraction algorithm for threshold segmentation and edge detection was programmed with MATLAB to realize accurate extraction and counting of the fluorescence signal of bacteria.The system had its performances verified with fluorescence detection performance test,fluorescence microscope control test and mixed live/dead bacterial sample scanning.Results The system was capable of simultaneous scanning detection of red and green fluorescence signals;the system obtained the images consistent with those by the fluorescence microscope,while had a larger detection field than the latter;there was a high correlation(R^2=0.9708)between the ratio of live/dead bacteria obtained by the system and the live bacteria content of the known sample.Conclusion The system can quickly complete accurate identification and quantitative analysis of live/dead bacteria,and thus is worthy promoting for microbial activity detection and quantitative analysis.