Novel Spectrofluorimetric Method For Determination Research Articles

A novel spectrofluorimetric method for determination of lomefloxacin adopting on zinc(II) chelation strategy: Application in human plasma.

A new sensitive and instantaneous spectrofluorimetric method for efficient determination of lomefloxacin (LMX) in its pure, dosage form and human plasma was designed. The developed method depends on formation of a metal-chelation compound of LMX as a ligand with zinc(II) in a buffer of acetate (pH5.5). The following parameters; type of metal, concentration of metal, pH, type of buffer and diluting solvent were optimized. After carefully investigation; 0.2mM zinc, 2.0ml acetate buffer (pH 5.5) and water as diluting solvent were set as optimum reaction conditions. Under these conditions, a large increase in the intensity of the fluorescence of LMX was attained at 450 after excitation at 284 nm. The limits of detection and quantification were 5.8 and 1.9 ng ml-1 , respectively, with linearity range of 10.0 to 500.0ng ml-1 . The binding mode of LMX and zinc(II) ion (Zn2+ ) was found to be 2:1, respectively, and confirmed by Job's plot method. Furthermore, it extended to the analysis of LMX in the spiked plasma of humans with percentage recovery (98.70 ±0.97 to 100.30 ±1.69%, n=3).

Resonance Rayleigh scattering technique-using erythrosine B, as novel spectrofluorimetric method for determination of anticancer agent nilotinib: Application for capsules and human plasma

A exceedingly touchy resonance Rayleigh scattering (RRS) strategy for the assurance of nilotinib (NILO) was introduced. In the pH 3.4 acetate buffer solution, NILO reacted with erythrosine B to produce an ion-association complex, which increased the RRS intensity of the studied system. The enhanced RRS intensity (ΔI) was linearly proportional to the concentration of NILO, the linear range of the method was 0.1–1.0 µg/mL and the detection limit (DL) was 0.025 µg/mL. In like manner, this test was connected to distinguish the concentration of NILO in capsules and human plasma with palatable comes about.

A novel spectrofluorimetric method for determination of imatinib in pure, pharmaceutical preparation, human plasma, and human urine.

The following paper represents a simple, highly sensitive, responsive validated and developed spectrofluorimetric method for estimation of imatinib (IMB) in its pure, commercial preparation, human urine and human blood plasma. The calibration curve was in the range 4-900ng ml-1 for pure form and urine and 8-900ng ml-1 for plasma in a medium contains carboxymethyl cellulose (CMC) and acetate buffer (pH5) with excitation wavelength (λex ) 230nm and emission wavelength (λem ) 307nm. The limit of detection (LOD) was 0.37ng ml-1 for the pure form, 0.64ng ml-1 for human urine, and 0.70ng ml-1 for human plasma, while the limit of quantitation (LOQ) was 1.2 for pure form, 1.91 for urine and 2.1 for plasma. The suggested method was successfully applied for evaluation of IMB in tablets within 99% mean percentage recovery. The excipients that are usually used as additives in pharmaceutical dosage form did not interfere with the suggested method. The method was efficiently used for estimation of IMB in human urine and human plasma. The effect of some cations that might be present in urine and plasma was also studied. The method was also focused on human volunteers and in vitro drug release.

Spectrofluorimetric study on the inclusion behavior of p-sulfonated calix arene with cetyltrimethylammonium bromide and analytical application

The characteristics of host–guest complexation between p-sulfonated calix [G. Arena, S. Gentile, F. G. Gulino, D. Sciotto, C. Sgarlata, Tetrahedron Lett. 45 (2004) 7091] arene (SC6A) and cationic surfactant cetyltrimethylammonium bromide (CTAB) were studied by fluorescence spectrometry. A 1:1 stoichiometry for the complexation was established and the complex constant was also calculated by a deduced equation. It was found the fluorescence of the complex could be remarkably quenched by an appropriate amount of ceftriaxone sodium (CTRX). Based on the results, a novel spectrofluorimetric method for determination of CTRX was developed with a linear range of 9.2×10 −7–8.5×10 −5 mol L −1 and a detection of 3.5×10 −7 mol L −1. The proposed method was used to determine CTRX in their commercial preparations with satisfactory results. Moreover, the probable interaction mechanisms of the systems were also discussed.

A novel spectrofluorimetric method for determination of lomefloxacin based on supramolecular inclusion complex between it and p-sulfonated calyx[4]arene

The characteristics of host–guest complexation between p-sulfonated calix[4]arene (SC4A) and lomefloxacin (LFLX) were investigated by fluorescence spectrometry. 1:1 stoichiometry for the complexation was established and their association constant at 25 °C was calculated by applying a deduced equation. The interaction mechanism of the inclusion complex was discussed. It was found that an appropriate amount of cationic surfactant cetyltrimethylammonium bromide (CTAB) could remarkably enhance the fluorescence intensity of the supramolecular complex system. Based on the obtained results, a novel sensitive spectrofluorimetric method for the determination of lomefloxacin was developed with a linear range of 0.01–3.0 μg ml −1 and a detection limit of 0.008 μg ml −1. The proposed method was applied satisfactorily to determine lomefloxacin in pharmaceutical preparations.

Micelle Enhanced Spectrofluorimetric Determination of L-ascorbic Acid Based on Laccase-linked Coupling Reaction Using Flow-injection Stopped-flow Technique.

A novel spectrofluorimetric method for determination of L-ascorbic acid is described. It is based on the inhibition of L-ascorbic acid on the formation of 2, 3-diaminophenazine, which is an oxidation product of o-phenylenediamine catalyzed by laccase, in the presence of Brij-35, which shows strong enhancement on the fluorescence(at λem/λex=530nm/430nm) of the product, while no effect on the laccase-catalyzed reaction. The mechanism of o-phenylenediamine oxidation reaction catalyzed by laccase in the presence of L-ascorbic acid is discussed. L-ascorbic acid is determined in the range of O.02-2.Oμg/ml with a detection limit of 0.014μg/ml. The method is applied to the determination of L-ascorbic acid in pharmaceuticals, the results agree well with the nominal values and those obtained by the reference method.