Yao Bo, Luo Guoan, Wang Liduo, Gao Yudi, Lei Gangtie, Ren Kangning, Chen Lingxin, Wang Yiming, Hu Yan, Qiu Yong
Department of Chemistry, Tsinghua University, Beijing, 100084, China.
Lab Chip. 2005 Oct;5(10):1041-7. doi: 10.1039/b504959h. Epub 2005 Aug 5.
A simply fabricated microfluidic device using a green organic light emitting diode (OLED) and thin film interference filter as integrated excitation source is presented and applied to fluorescence detection of proteins. A layer-by-layer compact system consisting of glass/PDMS microchip, pinhole, excitation filter and OLED is designed and equipped with a coaxial optical fiber and for fluorescence detection a 300 microm thick excitation filter is employed for eliminating nearly 80% of the unwanted light emitted by OLEDs which has overlaped with the fluorescence spectrum of the dyes. The distance between OLED illuminant and microchannels is limited to approximately 1 mm for sensitive detection. The achieved fluorescence signal of 300 microM Rhodamine 6G is about 13 times as high as that without the excitation filter and 3.5 times the result of a perpendicular detection structure. This system has been used for fluorescence detection of Rhodamine 6G, Alexa 532 and BSA conjugates in 4% linear polyacrymide (LPA) buffer (in 1 x TBE, pH 8.3) and 1.4 fmol and 35 fmol mass detection limits at 0.7 nl injection volume for Alexa and Rhodamine dye have been obtained, respectively.
本文介绍了一种简单制造的微流控装置，该装置使用绿色有机发光二极管（OLED）和薄膜干涉滤光片作为集成激发源，并将其应用于蛋白质的荧光检测。设计了一种由玻璃/聚二甲基硅氧烷（PDMS）微芯片、针孔、激发滤光片和OLED组成的逐层紧凑系统，并配备了同轴光纤。为了进行荧光检测，采用了一个300微米厚的激发滤光片，以消除OLED发出的近80%与染料荧光光谱重叠的不需要的光。OLED光源与微通道之间的距离限制在约1毫米，以实现灵敏检测。对于300微摩尔的罗丹明6G，所获得的荧光信号比没有激发滤光片时高约13倍，是垂直检测结构结果的3.5倍。该系统已用于在4%线性聚丙烯酰胺（LPA）缓冲液（在1×TBE，pH 8.3中）中对罗丹明6G、Alexa 532和牛血清白蛋白（BSA）缀合物进行荧光检测，对于Alexa和罗丹明染料，在0.7纳升进样体积下分别获得了1.4飞摩尔和35飞摩尔的质量检测限。
