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This paper proposes the recycling of poly (methyl methacrylate) plates, formerly used in LCD monitors to produce polymer optical fibers without cladding for sensor systems and a discussion about the fabrication process of the fiber cladding is briefly presented. After disassembling LCD monitors the acrylic plate is cleaned and submitted to an extrusion process. Extrusion temperatures of 220°C, 230°C and 240°C were applied, and the produced polymer fibers were characterized by infrared and visible spectrometry, as well as evaluated for thermal analysis through differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Furthermore, a refractive index sensor was developed with the recycled fibers. Results show that the recycled fiber refractive index sensor is linear (R = 0.99) and presents a sensitivity of more than 4 times higher when compared to a sensor using a commercial POF.

Sulindac is a non-steroidal antiinflammatory drug (NSAID) known to inhibit cyclooxygenases (COX) 1 and 2, and at present of interest for cancer prevention. However, its therapeutic use has been limited by its toxicity to the gastrointestinal tract and liver. We address the effects of sulindac, of the pharmacologically inactive metabolite, sulindac sulfone, and of the pharmacologically active metabolite, sudindac sulfide, on isolated rat liver mitochondria and HepG2 cells. Sulindac sulfide, but not sulindac sulfone or sulindac itself, caused mitochondrial uncoupling, released preaccumulated Ca 2π from the organelle, and decreased Hep-G2 cell viability in apparent association with cell ATP depletion resulting from mitochondrial uncoupling-associated membrane potential dissipation.

Since phosphate is strongly related to eutrophication of environmental waters, several research groups quest for materials that can efficiently remove phosphate from wastewaters before it contaminates lakes and reservoirs. In the present work, a commercial clay mineral (K10 montmorillonite) modified with Fe 3þ polyhydroxy cations was investigated as an adsorbent for phosphate. The incorporation of the polycations did not alter the main conformational characteristics of the montmorillonite, as verified by specific surface area measurements, X-ray diffractometry, FTIR, electron microscopy, and zeta potential titrations. On the other hand, the materials supporting Fe 3þ polyhydroxy cations exhibited a significant enhancement of adsorption capacity, as determined by Langmuir-Freundlich isotherms, from 39 AE 2 to 104 AE 15 μmol g À1 . The different ratios of OH À to Fe 3þ did not affect the adsorption capacities. The adsorption kinetics was best described by the pseudo 2 nd order model, approaching the equilibrium after 120 min of contact time. A variation of pH between 4.6 and 8.5 did not affect the adsorption percentages. The adsorption capacities increased with the increase of the ionic strength, thus suggesting that the formation of inner-sphere complexes prevails over electrostatic interactions as the adsorption mechanism. The materials removed phosphate from three polluted water samples having phosphate concentrations between 0.0919 and 1.211 mg L À1 . The remaining phosphate concentration was below the limit of quantification of the analytical method (0.063 mg L À1 in P, or 2.0 μmol L À1 ). The presence of 10 mg L À1 humic of fulvic acid did not affect the performance of the materials. In conclusion, the modification of clay minerals with Fe 3þ polyhydroxy cations is useful in producing low-cost adsorbents for phosphate.

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