Kwak Yeon Hwa, Lee Junhee, Lee Junghoon, Kwak Soo Hwan, Oh Sangwoo, Paek Se-Hwan, Ha Un-Hwan, Seo Sungkyu
Department of Electronics and Information Engineering, Korea University, Sejong 339-700, Republic of Korea.
J Microbiol Methods. 2014 Dec;107:150-6. doi: 10.1016/j.mimet.2014.10.004.
A novel biofilm detection platform, which consists of a cost-effective red, green, and blue light-emitting diode (RGB LED) as a light source and a lens-free CMOS image sensor as a detector, is designed. This system can measure the diffraction patterns of cells from their shadow images, and gather light absorbance information according to the concentration of biofilms through a simple image processing procedure. Compared to a bulky and expensive commercial spectrophotometer, this platform can provide accurate and reproducible biofilm concentration detection and is simple, compact, and inexpensive. Biofilms originating from various bacterial strains, including Pseudomonas aeruginosa (P. aeruginosa), were tested to demonstrate the efficacy of this new biofilm detection approach. The results were compared with the results obtained from a commercial spectrophotometer. To utilize a cost-effective light source (i.e., an LED) for biofilm detection, the illumination conditions were optimized. For accurate and reproducible biofilm detection, a simple, custom-coded image processing algorithm was developed and applied to a five-megapixel CMOS image sensor, which is a cost-effective detector. The concentration of biofilms formed by P. aeruginosa was detected and quantified by varying the indole concentration, and the results were compared with the results obtained from a commercial spectrophotometer. The correlation value of the results from those two systems was 0.981 (N = 9, P < 0.01) and the coefficients of variation (CVs) were approximately threefold lower at the CMOS image-sensor platform.
设计了一种新型生物膜检测平台，它由一个经济高效的红、绿、蓝发光二极管（RGB LED）作为光源和一个无透镜CMOS图像传感器作为探测器组成。该系统可以从细胞的阴影图像中测量其衍射图案，并通过简单的图像处理程序根据生物膜的浓度收集光吸收信息。与体积庞大且昂贵的商用分光光度计相比，该平台能够提供准确且可重复的生物膜浓度检测，并且简单、紧凑且成本低廉。对源自包括铜绿假单胞菌（P. aeruginosa）在内的各种细菌菌株的生物膜进行了测试，以证明这种新型生物膜检测方法的有效性。将结果与从商用分光光度计获得的结果进行了比较。为了将经济高效型光源（即LED）用于生物膜检测，对光照条件进行了优化。为了实现准确且可重复的生物膜检测，开发了一种简单的自定义编码图像处理算法，并将其应用于一个五百万像素的CMOS图像传感器，这是一种经济高效的探测器。通过改变吲哚浓度来检测和量化由铜绿假单胞菌形成的生物膜的浓度，并将结果与从商用分光光度计获得的结果进行比较。这两个系统结果的相关值为0.981（N = 9，P < 0.01），并且在CMOS图像传感器平台上变异系数（CVs）大约低三倍。
