a method based on the ultrasound-assisted solidification of floating drop microextraction technique was developed for the spectrophotometric and spectrofluorimetric determination of curcumin in turmeric powder. in this work a small volume of an organic solvent was floated on the surface of an aqueous solution. after sonication the organic solvent is solidified and separated. the effect of extra...

a simple, sensitive and accurate method for spectrophotometric determination of dalacinphosphatehas been established. the method is based on the reduction of atomic absorptioncalcium ion by phosphate. because, there is a phosphate mole in every dalacin mole structureand with measurement of phosphate, dalacin is beyond measurement too. therefore, the reactionbetween acidic hydrolysis products of...

A simple, sensitive and accurate method for spectrophotometric determination of Dalacinphosphatehas been established. The method is based on the reduction of atomic absorptioncalcium ion by phosphate. Because, there is a phosphate mole in every Dalacin mole structureand with measurement of phosphate, Dalacin is beyond measurement too. Therefore, the reactionbetween acidic hydrolysis products of...

We describe a liquid-chromatographic procedure for detection in urine of all thiazide drugs currently used clinically. Urine is treated initially with NaBH4 to convert any chlorothiazide present to hydrochlorothiazide. The urine is acidified with NaH2PO4 (1.0 mol/L, pH 5), and thiazides are extracted with ethyl acetate. Interfering substances are then removed in two washes with 0.1 mol/L Na2HPO...

Incorporation of a liquid waveguide capillary flow cell into a flow injection instrument enhances the sensitivity of flow injection analysis with spectrophotometric detection by two orders of magnitude. Nitrite determination at nM levels has been used to demonstrate the feasibility of this novel technique for trace analysis. Combining the long pathlength spectrophotometry with flow injection an...

The spectrophotometric methods of determination the active pharmaceutical ingredients meloxicam and nimesulide were reviewed a simple UV-spectrophotometric method for these in industrial equipment cleaning validation samples was proposed. based on extraction residual quantities from manufacturing surface by concentrated sodium carbonate solution subsequent basic forms drugs at wavelength 362 nm...

The most commonly used technique for water content determination is Karl-Fischer titration with electrometric detection, requiring specialized equipment. When appropriate equipment is not available, the method can be performed through visual detection of a titration endpoint, which does not enable an analysis of colored samples. Here, we developed a method with spectrophotometric detection of a...

Formaldehyde in small quantities is commonly analyzed by spectrophotometric methods. One of the most-commonly used spectrophotometric techniques for this purpose is based on the reaction with chromotropic acid. Because of its simplicity, sensitivity, selectivity and its low cost, it is still widely used. Investigations for replacing the concentrated sulfuric acid with other acids or using more ...

formaldehyde in small quantities is commonly analyzed by spectrophotometric methods. one of the most-commonly used spectrophotometric techniques for this purpose is based on the reaction with chromotropic acid. because of its simplicity, sensitivity, selectivity and its low cost, it is still widely used. investigations for replacing the concentrated sulfuric acid with other acids or using more ...