A compact multi-channel fluorescence sensor with ambient light suppression

作者：Egly Dominik^*; Geoerg Daniel; Raedle Matthias; Beuermann Thomas

来源：Measurement Science and Technology, 2012, 23(3): 035702.

DOI：10.1088/0957-0233/23/3/035702

• multi-channel fluorescence sensor
• ambient light suppression
• bioprocess monitoring
• biofluorophores
• biomedical diagnostics

A multi-channel fluorescence sensor has been developed for process monitoring and fluorescence diagnostics. It comprises a fiber-optic set-up with an immersion probe and an intensity-modulated high power ultraviolet light-emitting diode as a light source for fluorescence excitation. By applying an electronic lock-in procedure, fluorescence signals are selectively detectable at ambient light levels of 1000 000 times higher intensity. The sensor was designed to be compact, low cost and easily adaptable to a wide field of application. The set-up was used to simultaneously monitor three important metabolic fluorophores: NAD(P)H, flavins and porphyrins during the cultivation of a baker%26apos;s yeast. Moreover, the accumulation and degradation kinetics of protoporphyrin IX induced by 5-aminolevulinic acid on the skin could be recorded by the sensor. The detection limit for protoporphyrin IX was determined to be 4 x 10(-11) mol L-1. The linear signal amplification of the sensor and time courses of fluorescence signals monitored during yeast fermentations were validated using a commercial CCD spectrometer. The robust and flexible set-up of the fiber-optic measurement system promises easy implementation of this non-invasive analytical tool to fluorescence monitoring and diagnostics in R%26D and production.

• 出版日期2012-3