Flow-injection analysis for meloxicam based on tris(2,2'-bipyridine) ruthenium(II)-Ce(IV) chemiluminescent system.
It was found that meloxicam could enhance the chemiluminescence (CL) of the tris(2,2'-bipyridine) ruthenium(II)-Ce(IV) system in the medium of sulfate acid. Based on this phenomenon a new flow-injection system with chemiluminescent detection has been proposed for determination of meloxicam. Under optimum conditions, meloxicam had a good linear relationship with the CL intensity in the concentration range of 6.0 10(-4) to 1.0 microg/mL and the detection limit was 3.7 x 10(-4 )microg/mL. The proposed method was applied to detect meloxicam in tablets and a satisfactory recovery was obtained. The possible mechanism for this CL system is also discussed in this paper.
Flow-injection chemiluminescent determination of estrogen benzoate using the tris(1,10-phenanthroline) ruthenium(II)-permanganate system.
Chemiluminescence (CL) detection for the determination of estrogen benzoate, using the reaction of tris(1,10-phenanthroline)ruthenium(II)-Na(2)SO(3)-permanganate, is described. This method is based on the CL reaction of estrogen benzoate (EB) with acidic potassium permanganate and tris(1,10-phenanthroline)ruthenium(II). The CL intensity is greatly enhanced when Na(2)SO(3) is added. After optimization of the different experimental parameters, a calibration graph for estrogen benzoate is linear in the range 0.05-10 µg/mL. The 3 s limit of detection is 0.024 µg/mL and the relative standard deviation was 1.3% for 1.0 µg/mL estrogen benzoate (n = 11). This proposed method was successfully applied to commercial injection samples and emulsion cosmetics. The mechanism of CL reaction was also studied.
Separation of ibuprofen, codeine phosphate, their degradation products and impurities by capillary electrophoresis. II. Validation.
A micellar electrokinetic chromatography method for the determination of ibuprofen and codeine phosphate hemihydrate and their degradation products and impurities in a commercial tablet formulation has been validated. The validation has been performed according to the International Conference of Harmonisation's guidance on the validation of analytical methods, and selectivity, linearity, accuracy, precision, detection limit, quantitation limit, robustness and range test were performed to determine the suitability of the method. It was possible to use the fractional factorial design model from the optimisation of the method to draw conclusions about its robustness. The results confirm that the method is highly suitable for its intended purpose.