Biomedical subjects

B S Montenegro

Publications and source records attributed to B S Montenegro.

3 recordsLinked to original sources

PubMed1991

Vitamins B1 and B6 tubular electrodes as FIA detectors; their use in the analysis of pharmaceutical products.

Ion-selective electrodes without an inner reference solution and tubular potentiometric detectors for the determination of vitamins B1 and B6 in pharmaceutical preparations by flow injection analysis (FIA) are reported. The membranes were prepared with the vitamin tetra(2-chlorophenyl)borate (TCPB) dissolved in o-nitrophenyloctyl ether (o-NPOE) and immobilized on PVC. Intrinsic behaviour of the tubular detectors was assessed using a low-dispersion single-channel FIA manifold and was compared with conventionally-shaped electrodes using the same membrane. Data obtained in the determination of vitamins B1 and B6 in pharmaceutical preparations with a double channel flow injection manifold incorporating the tubular detectors are presented and compared with those obtained by the U.S. Pharmacopeia method and by direct potentiometry with conventionally-shaped electrodes.

Electrodes↗

PubMed1991

[Benzoate determination in medicinal syrups with a PVC membrane ion selective electrode without inner reference solution].

Two electrodes sensitives to benzoate ion, without inner reference solution, in which tetraoctylammonium benzoate in dibutylphtalate (type A) or 2-nitrophenyloctylether (type B) immobilized in PVC are used in membranes, applied on a conductive support, were prepared. The response characteristics and behaviour of this low-cost electrodes are presented. The analytical application possibilities are discussed and shown as practical examples on analyses of the ion in medicals syrups.

Benzoates↗

PubMed1989

Solid-state PVC flow-through benzoate electrode.

A general construction procedure for conventional shape ion-selective electrodes based on a conductive support prepared with a mixture of a non-conductive epoxy and graphite was used in the preparation of a flow-through benzoate electrode to be used as potentiometric detector in flow injection analysis manifolds. The membranes were prepared from tetraoctylammonium benzoate in o-nitrophenyloctylether immobilized on PVC. The results of the assessment of the tubular electrodes behaviour in low dispersion manifolds against that of conventional electrodes with the same membrane are reported. Data obtained with a double-channel flow injection manifold incorporating these tubular detectors for benzoate determinations in several commercially available pharmaceutical preparations are also presented.

Benzoates↗