the possibility of application of 4-nitrocatechol (4-nc) - tetrazolium salt - organic solventsystems for liquid-liquid extraction-spectrophotometric vanadium (iv and v) speciation wasstudied. six commercially available tetrazolium salts (2,3,5-triphenyltetrazolium chloride (ttc),3-(2-naphtyl)-2,5-diphenyltetrazolium chloride (tetrazolium violet, tv); 3-(4,5-dimethyl-2-thiazol)-2,5-diphenyltetra...

a simple and reproducible hplc method with spectrophotometric detection was developed for determination of rivastigmine in human plasma. liquid-liquid extraction of rivastigmine and donepezil (as internal standard) from plasma samples was performed with 1-butanol/n-hexane (2:98 v/v) in alkaline condition followed by back-extraction into diluted acetic acid. chromatography was carried out using ...

BACKGROUND AND AIMS Oncosurgeries may incur massive blood loss demanding frequent blood sampling to assess blood loss and the need for intraoperative blood transfusions. Accuracy of non-invasive spectrophotometric haemoglobin (hereafter to be referred as SpHb) monitoring has been studied in various perioperative settings. The intraoperative use of Radical-7®, Masimo Corp., (Radical-7®) for SpHb...

a sensitive and selective extraction - spectrophotometric method for the determination of trace amounts of palladium is reported. the method is based on quantitative extraction of brownish tetrabutylammoium tetraiodopalladium (ii) ion pair into a small valume of chloroform at ph 1.3-12.0, followed by spectrophotometric measurements. the beer's law is obeyed over the range 0.02-1.09 mgml-1 at 44...

naphthol isomers were simultaneously and spectrophotometrically determined in wastewater, using a model based on net analyte signal (nas). the calibration method used is a variation of the original hybrid linear analysis method as proposed by goicoechea and olivieri (hla/go). owing to spectral interferences, the simultaneous determination of mixtures of naphthol isomers, using a spectrophotomet...

BACKGROUND & OBJECTIVES Simple and reliable methods to estimate drugs in pharmaceutical products are needed. In most cases, antiretroviral drug estimations are performed using a HPLC method, requiring expensive equipment and trained technicians. A relatively simple and accurate method to estimate antiretroviral drugs in pharmaceutical preparations is by spectrophotometric method, which is cheap...

A novel spectrophotometric method for the estimation of carbon monoxide at levels from 2 to 250 ppm is presented. The method is empirical and based on formation of a carbonyl complex of ruthenium(II) octaethylporphyrin and measurement of the difference in absorbance at 393.5 nm between this complex and the porphyrin reagent. Oxygen and nitrogen do not interfere and up to 300 ppm of sulphur diox...

Aim to develop a methodology for quantitative spectrophotometric analysis of carvedilol in the "Carvedilosol" medication based on aquacomplex titanium glycerosolvate.
 Material and methods. During we used pharmaceutical substance "Carvedilol", gel "Tizol", ointment consisting 0.5% beta-blocker glycerohydrogel. The spectrophotometry was applied, registration optical density electron spectra...

We evaluated four spectrophotometric methods for suitability in determining total protein in human milk samples. Results were compared with those by an established method for the determination of total nitrogen (micro-Kjeldahl). Values for total protein by all four methods significantly correlated with micro-Kjeldahl. For the biuret assay, Lowry-Peterson assay, Bio-Rad Coomassie Blue assay, and...