An ultra-small, multi-point, and multi-color photo-detection system with high sensitivity and high dynamic range

Abstract

Although multi-point, multi-color fluorescence-detection systems are widely used in various sciences, they would find wider applications if they are miniaturized. Accordingly, an ultra-small, four-emission-point and four-color fluorescence-detection system was developed. Its size (space between emission points and a detection plane) is 15 × 10 × 12 mm, which is three-orders-of-magnitude smaller than that of a conventional system. Fluorescence from four emission points with an interval of 1 mm on the same plane was respectively collimated by four lenses and split into four color fluxes by four dichroic mirrors. Then, a total of sixteen parallel color fluxes were directly input into an image sensor and simultaneously detected. The emission-point plane and the detection plane (the image-sensor surface) were parallel and separated by a distance of only 12 mm. The developed system was applied to four-capillary array electrophoresis and successfully achieved Sanger DNA sequencing. Moreover, compared with a conventional system, the developed system had equivalent high fluorescence-detection sensitivity (lower detection limit of 17 pM dROX) and 1.6-orders-of-magnitude higher dynamic range (4.3 orders of magnitude).

An ultra-small nine-color spectrometer with a two-layer biparted ten-dichroic-mirror array and an image sensor

“…The developed nine-color spectrometer was applied to four-capillary-array electrophoresis (refer to Supplementary Material for details) 31 , 34 , 35 . The four-capillary array consists of four capillaries (with outer diameters of 360 μm and inner diameters of 50 μm) arranged at 1-mm intervals at laser-irradiation positions.…”

“…Recently, an ultra-small seven-color spectrometer (using a seven-dichroic-mirror array and an image sensor for measuring four fluorescence fluxes) was developed 31 . The spectrometer is two to three orders of magnitude smaller than a conventional spectrometer using a grating or a prism 34 , 35 . However, it is difficult to array more than seven dichroic mirrors in a spectrometer and simultaneously measure more than seven colors 36 , 37 .…”

Sophisticated and precise: design and implementation of a real-time optical detection system for ultra-fast PCR

“…Due to the different number of detection targets required for different diseases and the lack of detection scalability of a single channel, the optical detection module designed in this study can complete six channels of fluorescence detection, which has great potential for detection. 15–17…”

Highly sensitive mutation quantification by high-dynamic-range capillary-array electrophoresis (HiDy CE)

“…The four-dichroic-mirror array shown in Fig. 1f, which is the same as that used in the previous system, 31 was mounted on an adapter as shown in Fig. 1g.…”

“…In the meantime, an ultra-small (three-orders-of-magnitude smaller than a conventional detection system) multicolorfluorescence detection system for capillary-array electrophoresis has been recently developed. 31 Moreover, as an unexpected but invaluable by-product of that development, dynamic range of more than four orders of magnitude was obtained. In this study, therefore, the system was applied to high-dynamic-range capillary-array electrophoresis, termed "HiDy CE," for highly sensitive quantification of mutations.…”