Spectrophotometric analysis of the reaction of cellulose xanthate acid decomposition

1975 ◽  
Vol 6 (3) ◽  
pp. 351-352
Author(s):  
N. A. Mazur ◽  
V. G. Makeeva ◽  
K. A. Malyshevskaya ◽  
O. D. Chanchikova
1965 ◽  
Vol 9 (3) ◽  
pp. 1067-1072 ◽  
Author(s):  
Lyle H. Phifer ◽  
James P. Dux ◽  
Leland B. Ticknor ◽  
M. Thomas O'shaughnessy

2017 ◽  
Vol 63 (2) ◽  
pp. 1647-1652
Author(s):  
Sara Telyani ◽  
Esam Osman ◽  
Mohammad Rayyan ◽  
Ehab Farghaly ◽  
Ghada Hamza

1984 ◽  
Vol 49 (3) ◽  
pp. 673-679 ◽  
Author(s):  
Pavel Lederer ◽  
Eva Mácová ◽  
Josef Vepřek-Šiška

The decomposition of peroxobenzoic acid in benzene was studied, and catalytic effects of Fe(III), Mn(III), Co(II), Co(III), and Cr(III) on the reaction rate and the composition of the reaction mixture were investigated. An analogous experiment carried out in perdeuterobenzene and determination of the distribution of deuterium in the reaction products provided evidence for the participation of the solvent in peroxobenzoic acid decomposition.


2020 ◽  
Vol 17 (1) ◽  
pp. 29-33
Author(s):  
Kudirat B. Mustapha ◽  
Marlene D. Ekpo ◽  
Isa H. Galadima ◽  
Rukaiyatu A. Kirim ◽  
Olubukola A. Odeniran ◽  
...  

Erythromycin is one of the most frequently prescribed antibiotics. With the increasing number of pharmaceutical industries, the possibility of  purchasing a substandard product is on the high side. This makes it necessary to subject various commercially produced brands of erythromycin to quality evaluation in order to ascertain the quality. In this quality assessment study, six (6) brands of erythromycin tablets were subjected to physicochemical assay using standard physical methods and UV/VIS spectrophotometric analysis at 480 nm. The calibration curve for reference erythromycin was linear over a concentration range of 10-100 μg/ml with a correlation coefficient (R2) of 0.999. All the brands had standard deviation of weight greater than ±5 for the weight uniformity test. 66.67% of the brands passed the test for content of active ingredient. 83.33% of the brands examined passed the hardness test. All the brands failed the friability test because the percentage weight loss are greater than 1% as specified in the official book. Keywords: Erythromycin stearate; Tablets; Brands; Pharmaceutical Industries


Author(s):  
SACHIN A. YANJANE ◽  
SHRISHAIL M. GHURGHURE ◽  
VINOD K. MATOLE

Objective: A new, simple, economical, precise, sensitive, linear, accurate, rapid UV spectrophotometric method has been developed for the estimation of Oseltamivir Phosphate in pure form and pharmaceutical formulation. Methods: This UV method was developed using Methanol as a solvent. In the present method, the wavelength selected for analysis was 218 nm. UV-Visible double beam spectrophotometer (Systronic 2201) was used to carry out spectral analysis. The ICH guidelines were used to validate the method. Results: The method was validated for linearity, range, accuracy, precision, robustness, LOD and LOQ. Linearity was found in the range of 10-50µg/ml. Accuracy was performed by using a recovery study. The amount of drug recovered was found to be in the range of 99.01-100.1%. The % RSD value was found to be less than 2. Conclusion: The developed UV spectrophotometric method was found to be simple, economic, sensitive, easy, accurate, linear, specific and highly sensitive and can be used for routine estimation of Oseltamivir Phosphate.


Author(s):  
Ertan Kucuksayan ◽  
Serkan Ozben ◽  
Selma Topaloglu Tuac ◽  
Mesrure Koseoglu ◽  
Ozcan Erel ◽  
...  

Abstract Objectives Restless legs syndrome (RLS) is a common neurological condition. Oxidative stress plays an important role in its pathogenesis. Thiol-disulphide homeostasis (TDH) is a new biomarker of oxidative stress. We studied plasma TDH to determine whether TDH could be used as a new biomarker for RLS and evaluated correlations between TDH and various disease severity rating scales. Methods A total of 25 RLS patients and 25 healthy controls were included into the study. TDH status was determined using an automated spectrophotometric analysis method and correlations were analyzed between the TDH status and various disease rating scales in the RLS patients. Results Plasma total (401 ± 27 μmol/L) and native thiol (354 ± 30 μmol/L) levels were significantly lower, but disulphide level (24 ± 6 μmol/L) was significantly (<0.0001) higher in the RLS patients compared to the controls (455 ± 36, 424 ± 37, 15 ± 5 μmol/L, respectively). The disulphide/native thiol and disulphide/total thiol ratios increased, in contrast, native thiol/total thiol ratio decreased significantly in the RLS patients compared to the healthy controls (<0.0001). The disulphide levels correlated positively with age and various rating scores of the RLS patients. International Restless Legs Syndrome Study Group (IRLSSG) rating score and age correlated negatively with the total and native thiol levels. Conclusions Our findings indicate increased oxidative stress in the RLS patients reflected by decreased native and total thiol, and increased disulphide levels and positive correlations between the disulphide levels and various rating scores. We suggest dynamic TDH status to be used as a novel biomarker for the diagnosis and follow-up of the RLS patients.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 746
Author(s):  
Magdalena Turk ◽  
Rok Šibanc ◽  
Rok Dreu ◽  
Maja Frankiewicz ◽  
Małgorzata Sznitowska

This study concerned the quality of mini-tablets’ coating uniformity obtained by either the bottom spray chamber with a classical Wurster distributor (CW) or a swirl distributor (SW). Mini-tablets with a diameter of 2.0, 2.5, and 3.0 mm were coated with hypromellose using two different inlet air distributors as well as inlet airflow rates (130 and 156 m3/h). Tartrazine was used as a colorant in the coating layer and the coating uniformity was assessed by spectrophotometric analysis of solutions obtained after disintegration of the mini-tablets (n = 100). Higher uniformity of coating material distribution among the mini-tablets was observed in the case of SW distributor, even for the biggest mini-tablets (d = 3.0 mm), with an RSD no larger than 5.0%. Additionally, coating thickness was evaluated by colorimetric analysis (n = 1000), using a scanner method, and expressed as a hue value. A high correlation (R = 0.993) between inter-tablet variability of hue and UV-Vis results was obtained. Mini-tablets were successfully coated in a fluid bed system using both a classical Wurster distributor as well as a swirl generator. However, regardless of the mini-tablets’ diameter, better film uniformity was achieved in the case of a distributor with a swirl generator.


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