A disposable paper-based sensor (PBS) is described for the determination of Cu(II) in natural and waste waters at approximately 2 cents per measurement. The device makes use of a polymer inclusion membrane (PIM) to provide the selectivity for Cu(II). The PIM consists of 40 wt% di(2-ethlyhexyl) phosphoric acid (D2EHPA) as the carrier, 10 wt% dioctyl phthalate (DOP) as a plasticizer, 49.
View Article and Find Full Text PDFA general mathematical model of a flow-through optical chemical sensor prepared by the immobilization of 1-(2'-pyridylazo)-2-naphthol (PAN) into a commercial Nafion membrane was developed. The model takes into account the preparation of the optode membrane and in our opinion the most important chemical and physical processes involved in the generation of the analytical signal. The following model parameters were determined separately from the experimental verification of the model: aqueous diffusion coefficient of CuSO(4) - 8.
View Article and Find Full Text PDFA flow injection-column preconcentration-hydride generation atomic absorption spectrophotometric (FI-column-HGAAS) method was developed for determining mug/l levels of As(III) and As(V) in water samples, with simultaneous preconcentration and speciation. The speciation scheme involved determining As(V) at neutral pH and As(III+V) at pH 12, with As(III) obtained by difference. The enrichment factor (EF) increased with increase in sample loading volume from 2.
View Article and Find Full Text PDFAn optical chemical sensor responsive to selenium (SeO(3)(2-)) in water samples was developed. Its matrix was nafion membrane suffused with an organic ligand p-amino-p'-methoxydiphenylamine or variamine blue (VB). The method of analysis was flow injection (FI) where in the membrane was fixed in a flow-through demountable measuring cell and connected to a computer-controlled simple spectrophotometer.
View Article and Find Full Text PDFA copper-sensitive optical chemical sensor (optrode) is described. The optrode is based on a Nafion membrane and an immobilized organic ligand coupled with a flow injection (FI) system. The FI system includes a flow-through removable measuring cell and a simple spectrophotometer.
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