A green methodology was developed for the extraction and determination of lauryl ether sulfate in raw materials commercial liquid soap shower gel samples. The method avoids use organic solvents, offering a simple, cheap, safe analysis. is based on sorption an ionic pair consisting cationic dye anionic surfactant onto polyurethane foam. experimental variables were optimized by chemometry to obta...

The acid-base equilibrium of lorazepam was studied by means of potentiometry andmultiwavelengths spectrophotometry. The stoichiometric equilibrium constants were determinedat 25 °C and constant ionic strength 0.1 mol L-1 (NaCl). The acidity constants pK1=1.58±0.05and pK2=11.67±0.07 were found by potentiometry, and pK1=1.54±0.02 and pK2=11.61±0.03 bymulti-wavelengths spectrophotometry. Potentiom...

BACKGROUND Paraquat (PQ) is a world-wide used herbicide and also a type of common poison for suicide and accidental poisoning. Numerous studies have proved that the concentration of serum PQ plays an important role in prognosis. Spectrophotometry, including common spectrophotometry and second-derivative spectrophotometry, is commonly used for PQ detection in primary hospitals. So far, lack of s...

In this study, zero-, first-, secondand third-order derivative spectrophotometric methods were developed for quantitave determination of atenolol in pharmaceutical preparation. In zero order spectrophotometry, absorbance values were measured at 276 nm in zero order spectra of solution of atenolol in methanol in the range of 245-310 nm. In first derivative spectrophotometry, absorbance values we...

Measurements ~t 1.2, 1.~, and 2.2 μm have been combined with visual spectrophotometry o~ 21 quasai:s havmg. redshifts z ;:;: 2.66. T~e primary result of this study is that the rest frame vism~.l/ultravIC?let contmua of the high-redshift quasars are well described by a sum of a power-law contmuum with slope -.-0.~ ~nd a 3000 A bump. The rest frame visual/ultraviolet continua of these quasars are...

A rapid, simple and direct assay procedure based on first-derivative spectrophotometry, using a zero-crossing and peak-to-base measurement at 234 and 324 nm, respectively, has been developed for the specific determination of dextromethorphan HBr and bromhexine HCl in tablets. Calibration graphs were linear with the correlation coefficients of 0.9999 for both analytes. The limit of detections we...

Spectrophotometry has been the conventional technique for measuring optical density of irradiated gels [1]. Later, magnetic resonance imaging (MRI) was found to be capable of imaging radiation dose patterns in 3D [2]. Optical methods are still under investigation in the form of optical tomography [3– 6]. They promise to give three dimensional dose distributions without the cost attached to MRI....