Development of a simple and low-cost device for fluorometric determination of selenium in water samples.

A portable spectrofluorometer device comprising an ultraviolet LED (380 nm) as a light source, an LED driver, a microsyringe as a cell, an optical fiber cable, a CCD spectrometer and a personal computer was used on-site. The device works on a battery for 3 h without the need to re-charge. The consumptions of reagents and sample solution can be reduced by using the device.

Development of a discrete flow system using a microsyringe as a cell for the photometric determination of iron.

A simple discrete flow system for the photometric determination of iron using a glass syringe as a mixer of a solution and as a sample cell has been developed. The system was assembled from a coupler combining a light source (a light-emitting diode, LED), a glass syringe, a photodiode detector (PD) and two plastic core fiber optics. The reagent and sample solutions were sucked into a syringe, and were then mixed by a reciprocating motion of a plunger, or simply turning the syringe upside down several times, manually.