A new chromophoric reagent, 2-ketobutyric acid thiosemicarbazone (KBAT) has been used for the simultaneous determination of iron, copper and vanadium. KBAT forms yellowish-green and blue complexes with iron (II) and copper (II) respectively at pH 6.5 and a yellow complex with vanadium (V) at pH 5.5. Calibration graphs for the individual determinations by second derivative spectrophotometry were...

Solid-phase extraction method followed by direct UV spectrophotometry at 264 nm was developed and applied for the selective ibuprofen determination in two-component formulation of ibuprofen and pseudoephedrine-HCl, combined powder which contains ibuprofen in the form of salt with L-arginine and 10% ibuprofen cream. Procedures for ibuprofen determination in complex pharmaceutical preparations by...

Ricin is a toxic lectin which presents a potential security threat. Its rapid detection is highly desirable. Here we present a colorimetric bioassay based on the aggregation of carbohydrate-stabilised gold nanoparticles which has been used to detect Ricinus communis Agglutinin 120 (RCA(120)) - a ricin surrogate. To achieve a stable and robust sensing system the anchor chain length and the densi...

BACKGROUND Analysis of complex mixture containing three or more components represented a challenge for analysts. New smart spectrophotometric methods have been recently evolved with no limitation. A study of different novel and smart spectrophotometric techniques for resolution of severely overlapping spectra were presented in this work utilizing isosbestic points present in different absorptio...

1. Kronholm V, Lintrup J. Spectrophotometric investigation of the cerebrospinal fluid in the near-ultraviolet region. Acta Psychiatr Neurol Scand 1960;35: 314–29. 2. Buruma OJS, Janson HLF, van den Bergh FAJTM, Bots GTAM. Blood stained cerebrospinal fluid: traumatic puncture or haemorrhage? J Neurol Neurosurg Psychiatr 1981;44:144–7. 3. Vermeulen M, Gijn van J, Bleijenberg BG. Spectrophotometri...

Three new, simple, sensitive and selective spectrofluorimetric and spectrophotometric methods were developed for the determination of the γ-amino-n-butyric acid derivative, pregabalin. Pregabalin as a primary amine reacts with fluorescamine to yield a fluorescent product (Method I), with 2,4-dinitrofluorobenzene (Method II) and 2,3,5,6-tetrachloro-1,4-benzoquinone (Method III) in aqueous alkali...

Three sensitive, selective and reproducible stability-indicating methods are presented for determination of nitazoxanide (NTZ), a new anti-protozoal drug, in presence of its degradation products. Method A utilizes the first derivative of ratio spectra spectrophotometry by measurement of the amplitude at 364.4 nm using one of the degradation products as a divisor. Method B is a chemometric-assis...

The reaction of hydrogen peroxide and certain aromatic aldehydes with cytochrome P450BM3-F87G results in the covalent modification of the heme cofactor of this monooxygenase. Analysis of the resulting heme by electronic absorption spectrophotometry indicates that the reaction in the BM3 isoform is analogous to that in P450(2B4), which apparently occurs via a peroxyhemiacetal intermediate [Kuo e...

The affinity of the psychotropic benzodiazepine drugs diazepam (DZ) and flurazepam (FZ) to phosphatidylserine (PS) was examined since PS is abundantly contained in brain membranes. The effect of PS content on the partition coefficients (K(p)s) of these drugs between phosphatidylcholine (PC)-PS bilayer membranes of small unilamellar vesicles (SUV) and water was measured using second derivative s...

Abstract: Background: An anti-diabetic formulation consisting of vildagliptin and remogliflozin was prescribed for better glycemic control. In the present study a simple, rapid derivative spectrophotometric methods were evolved to analyze these two analytes from formulations. Methods: Two processed UV established by measuring peak amplitude at zero-crossing second spectra analytes. The procedur...