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B Cañabate Díaz

Publications and source records attributed to B Cañabate Díaz.

4 recordsLinked to original sources

A fluorescence optosensor for analyzing naphazoline in pharmaceutical preparations. Comparison with other sensors.

We have developed an optical sensor for determining and quantifying naphazoline (NPZ) based on its inherent fluorescence property. We have placed a non-ionic-exchanger solid support (Amberlite XAD-7) in a flow cell in the light path of the excitation beam and the fluorescence signal for NPZ is continuously monitored at lambda(exc/nm)=294/306 nm. The response time for this sensor is acceptably fast, 80s, obtaining a detection limit of 2.6 ng mL(-1) with standard deviations of 2.0% at 125 ng mL(-1). This device has been satisfactorily applied to two commercial formulations and its selectivity has been demonstrated with an interference study. The advantages have been compared with the only published sensor for determining NPZ in pharmaceutical preparations and with other analytical methods in the literature.

Adrenergic alpha-Agonists↗

Simultaneous determination of the pesticides carbaryl and thiabendazole in environmental samples by a three-dimensional derivative variable-angle and a synchronous room-temperature phosphorescence spectroscopy.

A three-dimensional derivative variable-angle synchronous scanning (DVASS) and a synchronous scanning (SS) heavy-atom room-temperature phosphorimetry (HAI-RTP) method are reported, for the first time, to identify and quantify the spectral overlapping phosphorescent pesticides thiabendazole (TBZ) and carbaryl (CBL). These pesticides are widely used in agriculture. The phosphorescence emission of the two compounds was obtained using sodium sulfite as the O2 scavenger and an external heavy atom salt. A careful selection of these experimental variables has been carried out. The increase of selectivity afforded by the DVASS and the SS methodology permitted the demonstration of its applicability to the simultaneous determination of phosphorescent signals of these two pesticides with overlapping spectral profiles. Limits of detection ranged between 1.4 ng/mL for TBZ and 1.7 ng/mL for CBL. The proposed method has been satisfactorily applied to the analysis of both pesticides in different types of water samples.

Carbaryl↗

Simple determination of propranolol in pharmaceutical preparations by heavy atom induced room temperature phosphorescence.

The applicability of heavy atom induced room temperature phosphorescence in real samples is demonstrated in this work. In this methodology only two reagents, potassium iodide as heavy atom salt and sodium sulphite as oxygen scavenger, were used to obtain phosphorescent signal of propranolol in solution. Thus a new simple, rapid and selective phosphorimetric method is proposed for propranolol determination in pharmaceutical preparations. The phosphorescence intensity was measured at 492 nm exciting at 294 nm. Phosphorescence was fully developed instantly, obtaining a linear concentration range between 0 and 500 ng ml(-1) with a detection limit of 14.4 ng ml(-1), an analytical sensitivity of 6.7 ng ml(-1) and a standard deviation of 1.4% at a 300 ng ml(-1) concentration level. The method has been successfully applied to the analysis of propranolol in an antidepressive pharmaceutical preparation and it was validated using standard addition methodology.

Luminescent Measurements↗

Room-temperature phosphorimetric method for the determination of the drug naphazoline in pharmaceutical preparations.

A selective and sensitive micelle-stabilized room-temperature phosphorimetric (MS-RTP) method for the determination of naphazoline in pharmaceutical preparations is described. The method is based on obtaining a phosphorescence signal from naphazoline using a micellar agent (sodium dodecyl sulfate), a heavy atom salt (TINO3) and a deoxygenation agent (Na2SO3). Optimization of the various conditions permitted the establishment of an MS-RTP method for naphazoline determination with a detection limit of 64.2 ng ml-1 and a relative standard deviation of 3.74% at the 500 ng ml-1 level. The method was applied to the analysis of pharmaceutical preparations.

Adrenergic alpha-Agonists↗