Alam Mohammad Wajih, Wahid Khan A, Goel Raghuveera Kumar, Lukong Kiven Erique
Department of Electrical and Computer Engineering, University of Saskatchewan, Saskatoon, SK S7N 5A9, Saskatchewan, Canada.
Department of Biochemistry, College of Medicine, University of Saskatchewan, Saskatoon, SK S7N 5E5, Saskatchewan, Canada.
Biomed Opt Express. 2019 Jan 4;10(2):399-410. doi: 10.1364/BOE.10.000399. eCollection 2019 Feb 1.
Instruments that allow the detection of fluorescence signal are invaluable tools for biomedical and clinical researchers. The technique is widely used in cell biology to microscopically detect target proteins of interest in mammalian cells. Importantly, fluorescence microscopy finds major applications in cancer biology where cancer cells are chemically labelled for detection. However, conventional fluorescence detection instruments such as fluorescence imaging microscopes are expensive, not portable and entail potentially high maintenance costs. Here we describe the design, development and applicability of a low-cost and portable fluorometer for the detection of fluorescence signal emitted from a model breast cancer cell line, engineered to stably express the green fluorescent protein (GFP). This device utilizes a flashlight which works in the visible range as an excitation source and a photodiode as the detector. It also utilizes an emission filter to mainly allow the fluorescence signal to reach the detector while eliminating the use of an excitation filter and dichroic mirror, hence, making the device compact, low-cost, portable and lightweight. The custom-built sample chamber is fabricated with a 3D printer to house the detector circuitry. We demonstrate that the developed fluorometer is able to distinguish between the cancer cell expressing GFP and the control cell. The fluorometer we developed exhibits immense potential for future applicability in the selective detection of fluorescently-labelled breast cancer cells.
能够检测荧光信号的仪器对于生物医学和临床研究人员来说是非常宝贵的工具。该技术在细胞生物学中被广泛用于显微镜下检测哺乳动物细胞中感兴趣的目标蛋白。重要的是，荧光显微镜在癌症生物学中有主要应用，其中癌细胞被化学标记以便检测。然而，传统的荧光检测仪器，如荧光成像显微镜，价格昂贵、不可便携，且维护成本可能很高。在此，我们描述了一种低成本、便携式荧光计的设计、开发及其适用性，该荧光计用于检测从经过工程改造以稳定表达绿色荧光蛋白（GFP）的模型乳腺癌细胞系发出的荧光信号。该设备利用一个在可见光范围内工作的手电筒作为激发源，并使用一个光电二极管作为探测器。它还使用一个发射滤光片，主要让荧光信号到达探测器，同时省去了激发滤光片和二向色镜的使用，因此，使该设备紧凑、低成本、便于携带且重量轻。定制的样品室是用3D打印机制造的，用于容纳探测器电路。我们证明，所开发的荧光计能够区分表达GFP的癌细胞和对照细胞。我们开发的荧光计在未来选择性检测荧光标记的乳腺癌细胞方面具有巨大的应用潜力。
