A miniaturized detection system for chemiluminescence that is generated on a microfluidic paper-based analytical device (μPAD) was developed using optical fibers and was applied to the determination of Cr(iii).

Fluorescent polymer nanocomposites of silsesquioxane cage-based anthracene (An-PSQ) and pyrene (Py-PSQ) were obtained by cross-linked polymerization of octavinylsilsesquioxane (OVS) with 9,10-dibromoanthracene or 1,6-dibromopyrene, respectively. The fluorescent polymers are insoluble and were structurally characterized by FT-IR and NMR. Polyaromatic spacer groups incorporated into materials could tune and rigidify in both micro-and mesoporous structures with high surface area in comparison to silica-based materials in the range of 246−342 m 2 / g, and their XRD analyses also show the amorphous nature. Both An-PSQ and Py-PSQ exhibit solvent-polarity-dependent photophysical properties in both light absorption and emission, which were employed in the anion sensing (i.e., F − , CN − ) in high polarity organic media. Importantly, excimer natures of polyaromatic spacer groups among silsesquioxane cages play an important role in the selectivity of anions in recognition. An-PSQ gives spectral changes in the presence of both F − and CN − , whereas replacing anthracenyl to pyrenyl group in Py-PSQ could selectively detect only F − because of a stronger excimer feature. Moreover, strong fluoride−silsesquioxane interaction has provided another function to these materials as adsorbent for highly hydrophilic F − anion from organic media containing water up to 77%.

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This work exploited the well-known iodine-starch reaction for development of a simple flow-injection (FI) method for determination of iodide in pharmaceutical samples. Iodide in an injected zone was oxidized to iodine. A gas diffusion unit enables selective permeation of iodine through a hydrophobic membrane. Detection was made very selective for elemental iodine by employing formation of the I(3)(-)-starch complex. The detection limit (3 S/ N) of the system was 1 mg I L(-1). For a liquid patent medicine used for asthma treatment we suggested modification of the system. Direct injection of this sample, which contains a particularly high concentration level of iodide (ca. 9000 mg I L(-1)), can be achieved by coupling a dialysis unit to the FI system. This has increased the working range to 6000-10,000 mg I L(-1) without employing complicated nanoliter injection.