Chromatographic and Surfactant Based Potentiometric Determination of Aqueous Dissociation Constant of Mupirocin

2020 ◽  
Vol 16 (2) ◽  
pp. 158-165 ◽  
Author(s):  
Natalija Nakov ◽  
Katerina Brezovska ◽  
Vasil Karchev ◽  
Jelena Acevska ◽  
Aneta Dimitrovska
Keyword(s):  
Linear Relationship ◽  
Dissociation Constant ◽  
Spectrophotometric Method ◽  
Tween 80 ◽  
Potentiometric Determination ◽  
Chromatography Method ◽  
Pka Values ◽  
Pka Value ◽  
Aqueous Pka

Background: The available data concerning aqueous dissociation constant of mupirocin (sparingly soluble drug) are scarce. In this study, chromatographic, surfactant based potentiometric concept and spectrophotometric method were used for determination of the aqueous pKa value of mupirocin. Methods: Different approaches were used for estimation of the aqueous pKa value from the apparent pKa values obtained at four ACN concentrations, ranging from 22% to 30%. The potentiometric determination of the pKa value of mupirocin was performed using different concentration of Tween 80 as a surfactant. Results: The aqueous pKa value of mupirocin, determined for the first time by reverse-phase liquid chromatography method, was found to be 4.76. The obtained value was confirmed by potentiometric method (4.85). It was found that Tween 80 increases the pKa values. The linear relationship between the apparent pKa values and the surfactant concentrations was used as an approach for estimation of the aqueous pKa value. Both methods gave similar values for aqueous pKa which correspond with the theoretically obtained pKa value (4.88) using Pallas computer program. It was found that mupirocin gives pH-indipendent spectra, thus spectrophotometric method is not applicable for determination of pKa of this compound. Conclusion: This comprehensive approach used for the pKa determination enable us to obtained reliable results for the aqueous pKa value of mupirocin. The linear relationship between the pKa values and the nonionic surfactant concentrations could be used as a reliable and simple approach for determination of aqueous pKa value of sparingly soluble drugs.

Chromatographic Determination of Thermodynamic Acid Dissociation Constants of Tetracycline Antibiotics and Their Epimers

2019 ◽  
Vol 57 (8) ◽  
pp. 745-750
Author(s):  
İlkay Konçe ◽  
Ebru Çubuk Demiralay ◽  
Hülya Yılmaz Ortak
Keyword(s):  
Experimental Data ◽  
Dissociation Constant ◽  
Binary Mixtures ◽  
Dissociation Constants ◽  
Reversed Phase ◽  
Acid Dissociation ◽  
Acid Dissociation Constant ◽  
Chromatography Method ◽  
Ph Values

Abstract The presented study describes the development of reversed-phase liquid chromatography method using a core-shell particle column with a pentafluorophenyl stationary phase for the dissociation constant (pKa) determination of the tetracycline group antibiotics (tetracycline, oxytetracycline, chlortetracycline) and their epimers (4-epitetracycline, 4-epioxytetracycline, 4-epichlortetracycline). The pH values were measured in the acetonitrile (ACN)–water binary mixtures, used as mobile phases, instead of in water and take into account the effect of the activity coefficients. Thermodynamic acid dissociation constant (pKa1) values of studied antibiotics and their epimers were calculated using retention factor (k) at different mobile phase pH values in studied binary mixtures with ACN percentages of 20, 25, 30 and 35% (v/v). Experimental data were analyzed by using an Origin 7.0 program to fit experimental data to the nonlinear expression derived. From calculated pKa1 values, the aqueous pKa values of studied compounds were calculated by different approaches and these values were compared.

scholarly journals IDENTIFICATION, QUANTIFICATION AND VALIDATION OF STIGMASTEROL FROM ALPINIA CALCARATA USING HIGH-PERFORMANCE THIN LAYER CHROMATOGRAPHY METHOD

2017 ◽  
Vol 9 (9) ◽  
pp. 126
Author(s):  
Pratheema Philomindoss
Keyword(s):  
Linear Regression ◽  
Thin Layer ◽  
Linear Relationship ◽  
High Performance ◽  
Retention Factor ◽  
Chromatography Method ◽  
Ich Guidelines ◽  
Layer Chromatography ◽  
Hptlc Method

Objective: The present study is designed to develop a new simple, precise, rapid and selective high‐performance thin‐layer chromatographic (HPTLC) method for the determination of stigmasterol in methanolic rhizomes extract of Alpinia calcarata.Methods: As per International Conference on Harmonization (ICH) guidelines we have applied different concentrations of stigmasterol as standard on HPTLC plates for the quantification of stigmasterol from the Alpinia calcarata rhizomes. The concentration of standard stigmasterol is 1 mg/ml.Results: The retention factor of stigmasterol was 0.58. Linearity was obtained in the range of 50 ng‐250 ng for stigmasterol. The developed and validated HPTLC method was employed for stigmasterol in methanolic rhizomes extract of Alpinia calcarata for standardization of the content of the marker. The linear regression data for the calibration plots showed a good linear relationship with r=0.99977 for stigmasterol, respectively Satisfactory recoveries of 99.77 % were obtained for stigmasterol.Conclusion: The results obtained in validation assays indicate the accuracy and reliability of the developed HPTLC method for the quantification of stigmasterol in methanolic rhizomes extract of Alpinia calcarata

scholarly journals Coulometric-potentiometric determination of pKA of several organic bases in propylene carbonate

2008 ◽  
Vol 73 (6) ◽  
pp. 655-659
Author(s):  
Ljiljana Jaksic ◽  
Radmila Dzudovic
Keyword(s):  
Propylene Carbonate ◽  
Supporting Electrolyte ◽  
Sodium Perchlorate ◽  
Potentiometric Method ◽  
Potentiometric Determination ◽  
Pka Values ◽  
Reference Base ◽  
Organic Bases ◽  
Standard Base

The pKA values of protonated triethylamine, pyridine and 2,2'-dipyridyl in propylene carbonate (PC) were determined by applying the coulometric-potentiometric method and a hydrogen/palladium generator anode (H2/Pd). The investigated and reference base were titrated to 50 % with protons electro-generated from hydrogen-saturated palladium, in the presence of sodium perchlorate as the supporting electrolyte. The half-neutralization potentials E1/2(x) and E1/2(st.) of the investigated and standard base, respectively, were measured using a glass-SCE pair. The obtained pKA values were compared with those reported in the literature.

scholarly journals A Sensitive Spectrophotometric Method for the Determination of Desloratadine in Tablets

2007 ◽  
Vol 90 (2) ◽  
pp. 372-375 ◽  
Author(s):  
Sena Çğalar ◽  
Aysel Öztun
Keyword(s):  
Spectrophotometric Method ◽  
Control Analysis ◽  
Optimum Conditions ◽  
Chromatography Method ◽  
Deep Blue ◽  
Quality Control Analysis ◽  
Significant Difference ◽  
Liquid Chromatography Method ◽  
First Time

Abstract A simple, rapid, and sensitive visible spectrophotometric method was developed, for the first time, for analysis of desloratadine (DE) in tablets. The method is based on the deep-blue colored TCNQ- radical anion formed by interaction of the drug (n-donor) with 7,7,8,8-tetracyanoquinodimethane (TCNQ, π-acceptor) in acetonitrile at ambient temperature. Optimum conditions for the reaction were investigated, absorbances were read at 843 nm, and the linearity range for concentrations of DE was found to be 1.5-13 μg/mL. The reaction product remains stable up to 8 h when kept at room temperature in the dark. The developed method was validated and successfully applied to the determination of DE in tablets. The tablets were also analyzed with a column liquid chromatography method reported in literature. The results from both methods were statistically compared by t- and F-tests. No significant difference was found for the means and standard deviations at 95% confidence level. Accuracy was examined through recovery studies. Being very simple and reliable, the method can be recommended for routine quality control analysis of DE in tablets.

scholarly journals NOVEL UV SPECTROPHOTOMETRIC METHOD FOR THE DETERMINATION OF TERIFLUNOMIDE IN TABLET DOSAGE FORM

2019 ◽  
pp. 81-84
Author(s):  
VISHWAS T. S. ◽  
GURUPADAYYA B. M.
Keyword(s):  
Linear Relationship ◽  
Spectrophotometric Method ◽  
Calibration Curve ◽  
Dosage Form ◽  
Current Work ◽  
Validation Parameters ◽  
Line Equation ◽  
Tablet Dosage ◽  
Ich Guideline

Objective: The current work is intended towards the development of a novel, simple, and precise UV spectrophotometric method for the estimation of teriflunomide (TEF) present in the marketed formulation. Methods: Acetonitrile was used as asolvent and the absorbance of the drug was measured at the absorbance maxima of TEF, UV 284 nm. Results: Calibration curve plotted in concentration range 5-10 µg /ml exhibited excellent linear relationship with line equation y = 0.0858x-0.0223 and r2 value of 0.9996. The method was found to comply all the validation parameters as per the ICH guideline indicating the sensitivity of the method towards analyte. Conclusion: The method can be used satisfactorily for the routine analysis of TEF present in marketed formulation.

Quantum Chemical Investigation on Indole: Vibrational Force Field and Theoretical Determination of Its Aqueous pKa Value

2013 ◽  
Vol 117 (31) ◽  
pp. 6846-6858 ◽  
Author(s):  
Andrea Pietropolli Charmet ◽  
Giuseppe Quartarone ◽  
Lucio Ronchin ◽  
Claudio Tortato ◽  
Andrea Vavasori
Keyword(s):  
Force Field ◽  
Quantum Chemical ◽  
Chemical Investigation ◽  
Theoretical Determination ◽  
Quantum Chemical Investigation ◽  
Pka Value ◽  
Aqueous Pka

Determination of Thiocyanate in Desulfurization Waste Solution by Spectrophotometry

2013 ◽  
Vol 634-638 ◽  
pp. 209-212
Author(s):  
Zhen Zhen Li ◽  
Guo Qiang Li ◽  
Yong Fa Zhang ◽  
Lin Wang ◽  
Yu Liang Shi ◽  
...  
Keyword(s):  
Linear Relationship ◽  
Spectrophotometric Method ◽  
Correlation Coefficients ◽  
Strong Absorption ◽  
Waste Solution ◽  
The Impact

Affects of thiosulfate (S2O32-) and sulfate (SO42-) on determination of thiocyanate (SCN-) in desulfurization waste solution (DWS) by spectrophotometry were investigated. The experiment results suggested that S2O32-and Fe3+ generated purple compound [Fe(S2O3)2]-which has a strong absorption at 450nm, but the purple soon fades in this process. As long as the reacting time is longer than 120s, the impact of S2O32-can be eliminated. In addition, sulfate has no effect. At 450nm wavelength, linear relationship between concentration of SCN-and absorbance was C=19.7272A-0.2774, which conformed to the Beer Law in the range of 2.00 ~ 19.45μg•ml-1, the correlation coefficients was 0.9996. The Fe3+-SCN-spectrophotometric method of monitoring SCN- in desulfurization waste solution was feasible.

Sign in / Sign up

Export Citation Format

Share Document