Citizen Science/Open Fluorometer Project/Resources/Yang 2009 Fluorometer

Bill of materials

 * Optics:
 * Concave blue LED (470nm)
 * LEDs were undergone continuous working under 20 mA current at least for 150 h to eliminate the initial low-frequency noise [1] W. Tong and E.S. Yeung, J. Chromatogr. A 718 (1995), p. 177. Abstract | PDF (607 K) | View Record in Scopus | Cited By in Scopus (28)[1].
 * lenses taken down from a waste DVD-ROM (Pioneer Electronic Co., Japan)
 * 25× ocular obtained from a pen microscope (Xiguang Technology Co., Xi’an, China)
 * 535-nm band-pass filter (10-nm band-pass, Shenyang HuiBo Optical Technology Co., Shenyang, China)
 * 1-mm pinhole
 * Photodiode (OPT301, Texas Instruments, Dallas, USA)
 * Electronics:
 * high gain amplifier AD620 (Analog Devices Instruments, Norwood, USA)
 * data collecting card (USB-6008, FanHua Measurement & Control Technology Co., Beijing, China)

Published performances

 * LOD 0.92 μM sodium fluorescein (S/N = 3)
 * Focusing spot diameter of 80 μm