Innovative design of a methodology for the simultaneous determination of compounds by kinetic-spectroscopy three-dimensional chemiluminescence.

This report presents a novel methodology based in the quickly acquisition of full UV-vis range spectra combined with the joint determination of kinetic parameters and chemiluminescence signals. Then this technique allows obtaining three-dimensional chemiluminescence spectra profiles containing kinetic and spectroscopic information. That is especially useful for resolving mixtures of luminophors because of more analytical information for each analyte is available increasing the selectivity relative to conventional chemiluminescence methods.

Development of a spectrofluorimetric method for the determination of ofloxacin in urine.

A simple, accurate, rapid, and sensitive spectrofluorimetric method for the determination of ofloxacin in urine was developed by means of first derivative matrix isopotential synchronous fluorescence spectrometry (MISF). The calibration curve was found to be linear in the concentration range 40-320 ng/mL. The method allows the determination of compound in samples with unknown background fluorescence without the need for tedious pre-separation.

Simultaneous determination of doxycycline and chlortetracycline in real samples by europium-sensitized luminescence.

A simple luminescent methodology for the simultaneous determination of doxycycline and chlortetracycline in pharmaceutical preparations and human urine is proposed. Since the native fluorescence of both analytes is negligible, this method takes advantage of the lanthanide-sensitized luminescence, which provides increased sensitivity. Due to the strong overlapping between the luminescence spectra of both europium complexes, the use of luminescence decay curves to resolve mixtures of the analytes is proposed, particularly as these curves are more selective.

Simultaneous determination of nabumetone and its principal metabolite in medicines and human urine by time-resolved fluorescence.

A simple fluorescent methodology for the simultaneous determination of nabumetone and its main metabolite, 6-methoxy-2-naphthylacetic acid (6-MNA), in pharmaceutical preparations and human urine is proposed. Due to the strong overlapping between the fluorescence spectra of both analytes, the use of fluorescence decay curves to resolve their mixture is proposed, since these curves are more selective. Values of dependent instrumental variables affecting the signal-to-noise ratio were fixed using a simplex optimization procedure.

Kinetic-spectrometric three-dimensional chemiluminescence as an effective analytical tool. Application to the determination of benzo(a)pyrene.

Kinetic and spectroscopic methods were used in combination in this work to develop a new analytical tool for use in chemiluminescence detection processes. Specifically, time-resolved chemiluminescence was used jointly with a stopped-flow assembly in order to monitor the chemiluminescence produced in the oxidation of bis(2,4-dinitrophenyl)oxalate (DNPO) by hydrogen peroxide in the presence of a polycyclic aromatic hydrocarbon. Recording of successive two-dimensional spectra during the emission process and treating the acquired spectral data with dedicated software allows the obtainment of three-dimensional chemiluminescence spectra, a result of the joint use of two analytical techniques.

Automatic chemiluminescence-based determination of carbaryl in various types of matrices.

Carbaryl, a modern pesticide widely used for both agricultural and non-agricultural purposes, was determined from the chemiluminescence produced in its reaction with Ce(IV) in a nitric acid medium containing rhodamine 6G as sensitizer, using flow-injection techniques. A straightforward automatic method based on measurements peak height and peak area, which are directly proportional to the carbaryl concentration, was thus developed. Calibration graphs are linear over the concentration range from 50 to 2000 ng mL(-1).