Construction of a compact spectrofluorometer/spectrophotometer system using a flexible liquid core waveguide

A liquid-core waveguide made of Teflon AF-2400 has been used to construct a simple, sensitive and robust instrument capable of performing fluorimetric and spectrophotometric analyses on aqueous solutions. The instrument, which uses a CCD array detection system, is unique in that high performance is achieved for both measurement techniques with minimal changes in instrument configuration. The fluorimetric detection limits for quinine sulfate and chlorophyll-a are 0.06 nanomolar and 0.03 nanomolar, respectively. Absorbance measurements using the same instrument demonstrate nanomolar detection capacities for hydrogen sulfide and subnanomolar detection limits for methylene blue.