scholarly journals Spectrophotometric determination of pyridoxal and pyridoxal 5′-phosphate with 3-methyl-2-benzothiazolone hydrazone hydrochloride, and their selective assay

1969 ◽  
Vol 114 (3) ◽  
pp. 629-633 ◽  
Author(s):  
Kenji Soda ◽  
Takamitsu Yorifuji ◽  
Haruo Misono ◽  
Mitsuaki Moriguchi

A spectrophotometric method with 3-methyl-2-benzothiazolone hydrazone hydrochloride was developed for the determination of pyridoxal and pyridoxal 5′-phosphate, and for the selective determination of each in the presence of the other. Pyridoxal and pyridoxal 5′-phosphate react with the reagent to yield the azine derivatives, which give characteristic absorption spectra. The highest extinction values are obtained when pyridoxal and pyridoxal 5′-phosphate are incubated at pH values of about 3·4 and 8·0 respectively; their maxima are at 430nm. (∈ 2·74×104) and 380nm. (∈ 2·24×104) respectively. The azine of pyridoxal is only slightly soluble under the neutral and alkaline conditions, whereas that of pyridoxal 5′-phosphate is substantially insoluble in the acid pH range. This difference in solubility of the azines made possible the selective determination of pyridoxal and pyridoxal 5′-phosphate. α-Oxoglutarate and pyruvate are among the substances shown not to interfere with the assay of pyridoxal; their derivatives absorb appreciably only at wavelengths below 420nm. For the assay of pyridoxal 5′-phosphate in the presence of these compounds measurement at 390nm. is necessary.

1970 ◽  
Vol 23 ◽  
pp. 93-101 ◽  
Author(s):  
T. P. Dhungana ◽  
P. N. Yadav

Spectrophotometric method using diphenylcarbazide as a colour developing reagent has been used to analyze the chromium content in tannery effluent located in Bara and Parsa districts of Nepal and Sirsiya River which is an ultimate drainage of these waste water streams. The adsorption of hexavalent chromium from aqueous solution onto formaldehyde treated sawdust and charcoal of sugarcane begasses has been investigated at various Cr(VI) concentrations of 5-40 mg/L and pH values. From the experimental observations, it has been found that chromium can be removed quantitatively at the equilibrium pH range of around 1 and the adsorption behavior revealed to follow Langmuir and Freundlich adsorption isotherms.Keywords : chromium, diphenylcarbazide, adsorption.DOI: 10.3126/jncs.v23i0.2102Journal of Nepal Chemical Society, Vol. 23, 2008/2009 Page; 93-101


2018 ◽  
Vol 33 (2) ◽  
pp. 41
Author(s):  
Chand Pasha ◽  
Badiadka Narayana

A simple spectrophotometric method for the determination of cefotaxime, ceftriaxone, cefadroxil and cephalexin with variamine blue is presented. The determination is based on the hydrolysis of β-lactam ring of cephalosporins with sodium hydroxide which subsequently reacts with iodate to liberate iodine in acidic medium. The liberated iodine oxidizes variamine blue to violet colored species of maximum absorption at 556 nm. The absorbance is measured within the pH range of 4.0-4.2. Beer’s law is obeyed in the range of 0.5-5.8 μg mL–1, 0.2-7.0 μg mL–1, 0.2-5.0 μg mL–1 and 0.5-8.5 μg mL–1 for cefotaxime, ceftriaxone, cefadroxil and cephalexin respectively. The analytical parameters were optimized and the method is successfully applied for the determination of cefotaxime, ceftriaxone, cefadroxil and cephalexin in pharmaceuticals.


2015 ◽  
Vol 1134 ◽  
pp. 28-33
Author(s):  
Mashri Ahmad Yahia ◽  
Musa Ahmad ◽  
Che Wan Zanariah Che Wan Ngah ◽  
Lee Yook Heng

Spectrophotometric determination of hydroxymethylfurfural (HMF) based on p-toluidine as a reagent has been studied. The absorption intensities were measured at a wavelength range of 250 to 500 nm to record the absorption spectra before and after reaction with the HMF. The solution response was obtained at pH 3. The concentration of HMF was 5 × 10-3M, whereas for p-toluidine was 8 × 10-3M .The relative standard deviation (R.S.D.) of reproducibility was 3.33% when concentration of p-toluidine 3 × 10-3M was used .The photostability was found to be good with 1.9 %. M was used . The photostability was found to be good with 1.9 %.


2010 ◽  
Vol 75 (5) ◽  
pp. 563-575 ◽  
Author(s):  
Moslem Mohammadi ◽  
Mehdi Khodadadian ◽  
Mohammad K. Rofouei

A plasticized poly(vinyl chloride) membrane electrode based on 4-[(5-mercapto-1,3,4-thiadiazol-2-ylimino)methyl]benzene-1,3-diol (L) for highly selective determination of palladium(II) (in PdCl42– form) is developed. The electrode showed a good Nernstian response (29.6 ± 0.4 mV per decade) over a wide concentration range (3.1 × 10–7 to 1.0 × 10–2 mol l–1). The limit of detection was 1.5 × 10–7 mol l–1. The electrode has a response time of about 20 s, and it can be used for at least 2 months without observing any considerable deviation from Nernstian response. The proposed electrode could be used in the pH range of 2.5–5.5. The practical utility of the electrode has been demonstrated by its use for the estimation of palladium content in aqueous samples.


1976 ◽  
Vol 59 (4) ◽  
pp. 807-810
Author(s):  
Jeffrey C Hamm

Abstract The USP analysis for procainamide HCl is titrimetric and relatively nonspecific, capsule and tablet dyes may interfere, and the method is not applicable to coated tablets. In the spectrophotofluorometric method the sample deteriorates when exposed to a xenon source. In the ultraviolet spectrophotometric method reported here, the sample is dispersed in acid medium, possible interferences are extracted in chloroform, base is added, procainamide is extracted in chloroform, the residue is dissolved in sodium hydroxide, and the compound is measured by absorption at 272 nm and comparison with a standard. Recoveries of standards added to capsule, tablet, and injection composites ranged from 99.3 to 102%. Twelve collaborators reported duplicate assay results for all 3 dosage forms with per cent standard deviations for 5 samples ranging from 1.01 to 1.27%. The method has been adopted as official first action.


1985 ◽  
Vol 68 (2) ◽  
pp. 205-208 ◽  
Author(s):  
Jois R Rangaswamy ◽  
Mysore Muthu

Abstract Phosphine residues were determined in 2 types of rice samples, raw polished and parboiled. The yellow chromophore due to phosphine from raw polished rice had 2 absorption maxima, a strong one at 370- 380 nm and a weaker one at 400-410 nm. The chromophore from parboiled rice also had 2, one at 390-400 nm and the other at 410-420 nm. A closed system containing rice and a phosphine tablet or powder yielded 93-99% recovery of fortified phosphine. At any given dose of phosphine, parboiled rice retained a higher amount of residue after aeration than did raw polished rice.


2010 ◽  
Vol 9 (2) ◽  
pp. 254-260
Author(s):  
Choirul Amri ◽  
Dwi Siswanta ◽  
Mudasir Mudasir

A study of extraction-spectrophotometric method for the determination of trace nitrite as 4-(4-nitrobenzenazo)-1-aminonaphthalene complex using n-amylalcohol and chloroform as organic solvents has been done. Results of the study showed that extraction-spectrophotometric determination of nitrite using n-amylalcohol or chloroform was very sensitive and had low limit of detection. Extraction-spectrophotometric method of nitrite using n-amylalcohol gave range of linear concentration 0.000-0.054 mg/L NO2--N, detection limit of 2.09x10-4 mg/L NO2--N, and sensitivity of 34.514 ± 0.398 absorbance unit per mg/L of NO2--N. Meanwhile, extraction-spectrophotometric of nitrite using chloroform had range of linear concentration of 0.000-0.100 mg/L NO2--N, detection limit of 8.99x10-4 mg/L NO2--N, and sensitivity of 18.353 ± 0.456 absorbance unit per mg/L NO2--N.   Keywords: Nitrite Trace, 4-(4-Nitrobenzenazo)-1-Aminonaphthalene, Extraction-Spectrophotometry


2021 ◽  
Vol 9 (2) ◽  
pp. 64-71
Author(s):  
Mykola Blazheyevskiy ◽  
◽  
Valeriy Moroz ◽  
Olena Mozgova ◽  
◽  
...  

The oxidative derivatization method using potassium hydrogenperoxomonosulfate for the indirect spectrophotometric determination of Fluphenazine hydrochloride is presented. Potassium hydrogenperoxomonosulfate is introduced as a derivatizing agent for Fluphenazine hydrochloride, yielding the sulfoxide. This reaction product was successfully used for the spectrophotometric determination of the Fluphenazine hydrochloride. The UV spectroscopic detection of the sulfoxide proved to be a more robust and sensitive method. The elaborated method allowed the determination of Fluphenazine hydrochloride in the concentration range of 0.2-30 µg mL-1. The molar absorptivity at 349 nm is 5.6×103 (dm3cm-1mol-1). The limit of quantification, LOQ (10S) is 0.24 µg/mL. A new spectrophotometric technique was developed and the possibility of quantitative determination of Fluphenazine hydrochloride in tablets 5.0 mg was demonstrated. The present method is precise, accurate and excipients did not interfere. RSD for Fluphenazine Hydrochloride 5.0 mg tablets was 1.37 %.


2011 ◽  
Vol 8 (1) ◽  
pp. 110-117 ◽  
Author(s):  
Baghdad Science Journal

A simple, accurate and sensitive spectrophotometric method for the determinaion of epinephrine is described . The method is based on the coordination of Pr (III) with epinephrine at pH 6. Absorbance of the resulting orange yellow complex is measured at 482 nm . A graph of absorbance versus concentrations shows that beer 's low is obeyed over the concentration range (1-50)mg.ml-1 of epinephrine with molar absorpitivity of ( 2.180x103 L.mol-1.cm-1 ), a sandell sensitivity of (0.084 mg.cm-2 ), a relative error of (-2.83%) , a corrolation coffecient (r= 0.9989) and recovery % ( 97.03 ± 0.75 ) depending on the concentration.This method is applied to analyse EP in several commercially available pharmaceutical preparations using direct methods .All statistical calculations are implemented via a Minitab software version 11.


1938 ◽  
Vol 21 (4) ◽  
pp. 411-430 ◽  
Author(s):  
Aurin M. Chase ◽  
Charles Haig

The absorption spectra of visual purple solutions extracted by various means were measured with a sensitive photoelectric spectrophotometer and compared with the classical visual purple absorption spectrum. Hardening the retinas in alum before extraction yielded visual purple solutions of much higher light transmission in the blue and violet, probably because of the removal of light-dispersing substances. Re-extraction indicated that visual purple is more soluble in the extractive than are the other colored retinal components. However, the concentration of the extractive did not affect the color purity of the extraction but did influence the keeping power. This suggests a chemical combination between the extractive and visual purple. The pH of the extractive affected the color purity of the resulting solution. Over the pH range from 5.5 to 10.0, the visual purple color purity was greatest at the low pH. Temperature during extraction was also effective, the color purity being greater the higher the temperature, up to 40°C. Drying and subsequent re-dissolving of visual purple solutions extracted with digitalin freed the solution of some protein impurities and increased its keeping power. Dialysis against distilled water seemed to precipitate visual purple from solution irreversibly. None of the treatments described improved the symmetry of the unbleached visual purple absorption spectrum sufficiently for it to resemble the classical absorption spectrum. Therefore it is very likely that the classical absorption spectrum is that of the light-sensitive group only and that the absorption spectra of our purest unbleached visual purple solutions represent the molecule as a whole.


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