Simplex optimization of the variables affecting the micelle-stabilized room temperature phosphorescence of 6-methoxy-2-naphthylacetic acid and its kinetic determination in human urine.
This article reports the kinetic determination of 6-methoxy-2-naphthylacetic acid (6-MNA), the major metabolite of nabumetone, from micelle-stabilized room temperature phosphorescence (MS-RTP) measurements made by using the stopped-flow mixing technique. This methodology allows one to determine analytes in complex matrices without the need for a tedious separation process. It also shortens analysis times substantially. The proposed method uses simplex methodology to optimize the chemical and instrumental variables affecting the phosphorescence. It was applied to the determination of 6-MNA in human urine. The maximum phosphorescence signal is obtained within only 10 s after the sample is prepared. The maximum slope of the kinetic curve, which corresponds to the maximum rate of the phosphorescence development, is measured at lambda(ex)=273 nm and lambda(em)=516 nm. Least-squares regression was used to fit experimental data, and the detection limit, repeatability, and standard deviation for replicate samples were determined.
Pulgarín
J A Murillo
JA
Department of Analytical Chemistry and Foods Technology, University of Castilla-La Mancha, 13071, Ciudad Real, Spain. joseantonio.murillo@uclm.es
Molina
A Alañón
AA
Pardo
M T Alañón
MT
D004791:Enzyme Inhibitors / Q000652:urine*; D006801:Humans; D007700:Kinetics; D008163:Luminescent Measurements; D008823:Micelles; D009280:Naphthaleneacetic Acids / Q000652:urine*; D013696:Temperature
D004791:Enzyme Inhibitors; D008823:Micelles; D009280:Naphthaleneacetic Acids; C044612:6-methoxy-2-naphthylacetic acid