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Andrade ÂL, Cardoso TD, Thomasi SS, Alvarenga ME, da Silva MAN, Magalhães EJ, Duarte HA, de Almeida KJ. A simple and efficient method for simultaneous quantification of levodopa and carbidopa based on controlled oxidation process. CHEMICAL PAPERS 2021. [DOI: 10.1007/s11696-021-01532-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Stojanović J, Krmar J, Protić A, Svrkota B, Đajić N, Otašević B. Experimental design in HPLC separation of pharmaceuticals. ARHIV ZA FARMACIJU 2021. [DOI: 10.5937/arhfarm71-32480] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Design of Experiments (DoE) is an indispensable tool in contemporary drug analysis as it simultaneously balances a number of chromatographic parameters to ensure optimal separation in High Pressure Liquid Chromatography (HPLC). This manuscript briefly outlines the theoretical background of the DOE and provides step-by-step instruction for its implementation in HPLC pharmaceutical practice. It particularly discusses the classification of various design types and their possibilities to rationalize the different stages of HPLC method development workflow, such as the selection of the most influential factors, factors optimization and assessment of the method robustness. Additionally, the application of the DOE-based Analytical Quality by Design (AQbD) concept in the LC method development has been summarized. Recent achievements in the use of DOE in the development of stability-indicating LC and hyphenated LC-MS methods have also been briefly reported. Performing of Quantitative structure retention relationship (QSRR) study enhanced with DOE-based data collection was recomended as a future perspective in description of retention in HPLC system.
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Burmaoğlu RE, Sağlık Aslan S. A rapid liquid chromatography/tandem mass spectrometry method for simultaneous determination of levodopa, carbidopa, entacapone and their six related compounds in film-coated tablets. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2020; 34:e8782. [PMID: 32170976 DOI: 10.1002/rcm.8782] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 03/10/2020] [Accepted: 03/10/2020] [Indexed: 06/10/2023]
Abstract
RATIONALE A liquid chromatography/tandem mass spectrometry (LC/MS/MS) method has been developed and validated to determine levodopa, carbidopa, entacapone, and corresponding six related substances - levodopa impurity B, levodopa impurity C, methyldopa, methylcarbidopa, entacapone impurity C, and entacapone impurity A - in film-coated tablets for the first time. METHODS Chromatographic separation was achieved with a gradient elution by using a C18 column, a mobile phase containing 0.5% formic acid in water and 0.5% formic acid in methanol. The mobile phase flow rate was 0.5 mL min-1 . The UV detector was set at 280 nm and the triple quadrupole mass spectrometer was used in multiple reaction monitoring (MRM) mode. RESULTS The limit of detection (LOD) and limit of quantification (LOQ) results were 1.3 and 3.94 ng mL-1 for levodopa impurity B; 5.26 and 15.9 ng mL-1 for levodopa impurity C; 0.833 and 2.53 ng mL-1 for methyldopa; 3.31 and 10.0 ng mL-1 for methylcarbidopa; 1.67 and 5.06 ng mL-1 for entacapone impurity C; and 0.61 and 1.86 ng mL-1 for entacapone impurity A. CONCLUSIONS The method was rapid, linear, accurate, and reproducible. The LC/MS/MS method that was developed to determine the related substances and assay of levodopa, carbidopa, and entacapone can be used to evaluate the quality of regular samples in the pharmaceutical industry. It can be also used to test the stability of samples.
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Affiliation(s)
- Rıfat Emre Burmaoğlu
- Faculty of Pharmacy, Department of Analytical Chemistry, Istanbul University, 34116 Beyazıt, Istanbul, Turkey
| | - Serap Sağlık Aslan
- Faculty of Pharmacy, Department of Analytical Chemistry, Istanbul University, 34116 Beyazıt, Istanbul, Turkey
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Đajić N, Krmar J, Malenović A, Otašević B, Protić A. Chaotropic effect of trifluoroacetic and perchloric acid on B-cyclodextrin inclusion complexation process with risperidone, olanzapine and their selected impurities. ARHIV ZA FARMACIJU 2020. [DOI: 10.5937/arhfarm70-28865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Effective method development together with method`s eco-friendly character are gaining importance in drug analyses nowadays. One of the strategies often applied to improve the efficacy of separation methods, especially in the case of basic ionizable analytes is adding chaotropic salts into the mobile phases. Moreover, the development of the green liquid chromatography method could also be achieved with certain mobile phase additives such as cyclodextrin (CD). The study aims to investigate whether adding chaotropic agents could improve the complexation process by disrupting the analytes' water solvation shell. The model mixture consisted of risperidone, olanzapine, and their related impurities. Method development was aided with experimental design methodology, while optimal separation conditions were selected using Derringer's desirability function. Mathematical models obtained for each of the examined responses enabled the explanation of the single and simultaneous influence of b-CD concentration, chaotropic agents type, and content, as well as the content of acetonitrile in the mobile phase. Retention factors appeared to be the most influenced by acetonitrile content in the mobile phase. The type of chaotropic agent as well as its concentration lead to retention prolongation, but if acetonitrile content in the mobile phase is high, the effect of chaotropic agent becomes negligible. Interaction between analyte and b-CD are relatively weak in comparison to the interaction of analyte form with either chaotropic agent or acetonitrile. Interaction leading to complexation are outperformed by other analyte related interactions in this complicated system, so complexation based retention reduction is not fully exposed. However, increasing b-CD concentration shows a positive effect on the resolution between critical peak pairs. Optimal separation conditions were selected based on 3D plots of Derringer's desirability function. For olanzapine and its impurity, they included the following: acetonitrile content 16% (v/v), trifluoroacetic acid as a chaotropic agent with 0.95% (v/v) content, and 9 mM b-CD concentration. Further, optimal separation conditions for risperidone and its impurity were 25% (v/v) acetonitrile content in the mobile phase, trifluoroacetic acid as chaotrope agent with 0.27% (v/v) content and 5mM b-CD concentration.
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Shelke M, Deshpande SS, Sharma S. Quinquennial Review of Progress in Degradation Studies and Impurity Profiling: An Instrumental Perspective Statistics. Crit Rev Anal Chem 2019; 50:226-253. [DOI: 10.1080/10408347.2019.1615863] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Madhav Shelke
- School of Pharmacy & Technology Management, SVKM's NMIMS, Shirpur, Maharashtra, India
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Robust Optimization of Chaotropic Chromatography Assay for Lamotrigine and its Two Impurities in Tablets. Chromatographia 2018. [DOI: 10.1007/s10337-018-3661-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Beitollahi H, Salimi H, Ganjali MR. Selective Determination of Levodopa in the Presence of Vitamin B 6, Theophylline and Guaifenesin Using a Glassy Carbon Electrode Modified with a Composite of Hematoxylin and Graphene/ZnO. ANAL SCI 2018; 34:867-873. [PMID: 30101879 DOI: 10.2116/analsci.17p526] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
An electrode has been developed based on using a composite of hematoxylin/graphene/ZnO nanocomposite to modify a glassy carbon electrode (GCE). The electrode (HGGCE) was tested and found to be applicable for the voltammetric analysis of levodopa in the presence of vitamin B6, theophylline and guaifenesin using a 0.1 M phosphate buffer solution (PBS) pH 7 as the solvent. The HGGCE was used as the working electrode in cyclic voltammetry (CV) and square wave voltammetry (SWV) studies on the electrochemical behavior of levodopa at its surface. The results showed a dramatic enhancement in the oxidation current of levodopa and a shift in its oxidation potential towards more negative potentials as opposed to identical tests using bare GCE as the working electrode. The studies showed that the increase in the oxidation current has two linear profiles in two concentration ranges of 0.05 - 90.0 and 90.0 - 1000.0 μM. The detection limit of SWV analysis using the modified electrode was determined to be 0.03 μM (S/N = 3). Further advantages of the methods based on HGGCE include the simple modification procedure of the electrode, as well as its excellent sensitivity and reproducibility. The modified electrode was eventually found to be applicable to the determination of mixtures of levodopa, vitamin B6, theophylline and guaifenesin in real samples.
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Affiliation(s)
- Hadi Beitollahi
- Environment Department, Institute of Science and High Technology and Environmental Sciences, Graduate University of Advanced Technology
| | - Hadiseh Salimi
- Department of Chemistry, Graduate University of Advanced Technology
| | - Mohammad Reza Ganjali
- Center of Excellence in Electrochemistry, University of Tehran.,Biosensor Research Center, Endocrinology & Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Sciences
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Čolović J, Kalinić M, Vemić A, Erić S, Malenović A. Influence of the mobile phase and molecular structure parameters on the retention behavior of protonated basic solutes in chaotropic chromatography. J Chromatogr A 2017; 1511:68-76. [PMID: 28697932 DOI: 10.1016/j.chroma.2017.06.069] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 06/26/2017] [Accepted: 06/27/2017] [Indexed: 11/17/2022]
Abstract
In this study, we present novel insights into the pH-dependent retention behavior of protonated basic solutes in chaotropic chromatography. To this end, two sets of experiments were performed to distinguish between mobile phase pH and ionic strength effects. In the first set, the ionic strength (I) was varied with the concentration of NaPF6 and additives that adjusted the mobile phase pH, while in the second set, I was kept constant by adding the appropriate amount of NaCl. In each set, the retention behavior of 13 analytes was qualitatively examined in 21 chromatographic systems, which were defined by the NaPF6 concentration in their aqueous phases (1-50mM) and the pH of their mobile phases (2, 3 or 4); the acetonitrile content was fixed at 40%. The addition of NaCl significantly reduced the differences among retention factors at studied pH values due to the effect of the Na+ ions on PF6-adsorption to the stationary phase and the magnitude of the consequential development of the surface potential. A quantitative description of the observed phenomenon was obtained by an extended thermodynamic approach. The contribution of ion-pair formation in the stationary phase to the retention of the solutes was confirmed across models at the studied pH values in the set with varying I. In the systems with a constant I, the shielding effect of the Na+ ions on the surface charge lowered the attractive surface potential and diminished the aforementioned interactions and hence the effect of the mobile phase pH on analyte retention. Eventually, we developed a readily interpretable empirical retention model that simultaneously takes into account analyte molecular structures and the most relevant chromatographic factors. Its coefficients have clear physical meaning, and owing to its good predictive capabilities, the model could be successfully used to clarify the contributions of analyte molecular structures and chromatographic factors to the specific processes underlying separation in chaotropic chromatography.
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Affiliation(s)
- Jelena Čolović
- University of Belgrade - Faculty of Pharmacy, Department of Drug Analysis, Vojvode Stepe 450, Belgrade, Serbia
| | - Marko Kalinić
- University of Belgrade - Faculty of Pharmacy, Department of Pharmaceutical Chemistry, VojvodeStepe 450, Belgrade, Serbia
| | - Ana Vemić
- Slaviamed, Bulevar oslobođenja 177, Belgrade, Serbia
| | - Slavica Erić
- University of Belgrade - Faculty of Pharmacy, Department of Pharmaceutical Chemistry, VojvodeStepe 450, Belgrade, Serbia
| | - Anđelija Malenović
- University of Belgrade - Faculty of Pharmacy, Department of Drug Analysis, Vojvode Stepe 450, Belgrade, Serbia.
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Design of Experiments–Design Space Approach for Development of Chaotropic Chromatography Method for Determination of Trimetazidine Dihydrochloride and Two Impurities. Chromatographia 2017. [DOI: 10.1007/s10337-017-3275-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Abdel-Ghany MF, Hussein LA, Ayad MF, Youssef MM. Investigation of different spectrophotometric and chemometric methods for determination of entacapone, levodopa and carbidopa in ternary mixture. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2017; 171:236-245. [PMID: 27541796 DOI: 10.1016/j.saa.2016.07.053] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 07/24/2016] [Accepted: 07/31/2016] [Indexed: 06/06/2023]
Abstract
New, simple, accurate and sensitive UV spectrophotometric and chemometric methods have been developed and validated for determination of Entacapone (ENT), Levodopa (LD) and Carbidopa (CD) in ternary mixture. Method A is a derivative ratio spectra zero-crossing spectrophotometric method which allows the determination of ENT in the presence of both LD and CD by measuring the peak amplitude at 249.9nm in the range of 1-20μgmL-1. Method B is a double divisor-first derivative of ratio spectra method, used for determination of ENT, LD and CD at 245, 239 and 293nm, respectively. Method C is a mean centering of ratio spectra which allows their determination at 241, 241.6 and 257.1nm, respectively. Methods B and C could successfully determine the studied drugs in concentration ranges of 1-20μgmL-1 for ENT and 10-90μgmL-1 for both LD and CD. Methods D and E are principal component regression and partial least-squares, respectively, used for the simultaneous determination of the studied drugs by using seventeen mixtures as calibration set and eight mixtures as validation set. The developed methods have the advantage of simultaneous determination of the cited components without any pre-treatment. All the results were statistically compared with the reported methods, where no significant difference was observed. The developed methods were satisfactorily applied to the analysis of the investigated drugs in their pure form and in pharmaceutical dosage forms.
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Affiliation(s)
- Maha F Abdel-Ghany
- Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Ain-Shams University, Abbassia, Cairo 11566, Egypt
| | - Lobna A Hussein
- Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Ain-Shams University, Abbassia, Cairo 11566, Egypt
| | - Miriam F Ayad
- Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Ain-Shams University, Abbassia, Cairo 11566, Egypt
| | - Menatallah M Youssef
- Pharmaceutical Analytical Chemistry Department, Faculty of Pharmacy, Ain-Shams University, Abbassia, Cairo 11566, Egypt.
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Purnachand D, Veerareddy A, Ramadevi B, Kameswarrao CVSL, Madhusudhanreddy B. Development and Validation of a RP-HPLC Method for Determination of Related Substances and Degradants in Entacapone. J Chromatogr Sci 2016; 54:1310-23. [PMID: 27165569 DOI: 10.1093/chromsci/bmw083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2015] [Indexed: 11/13/2022]
Abstract
A new reverse phase-liquid chromatography (RP-HPLC) method has been developed for simultaneous determination of entacapone and its pharmacopoeia impurities, in-house impurities and degradation impurities (total 17 analytes). Chromatographic separation was achieved on a C18 column (size: 250 × 4.6 mm; 5 µm particle size) at a flow rate of 1.0 mL/min with 210 nm detection. The mobile phase (MP) consists of 1.361 g of potassium di-hydrogen phosphate and 1.742 g of di-potassium phosphate in 1.0 L water, pH adjusted to 2.5 with ortho phosphoric acid (MP-A) and acetonitrile (MP-B) through gradient elution. The product was subjected to stress conditions such as acid, base, peroxide, thermal and photolytic degradation. Two new impurities above 2% level were observed and isolated through preparative HPLC and well characterized. However, no interference observed due to degradation impurities and entacapone and its EP impurities, in-house impurities. As part of the method validation, specificity, limit of detection, limit of quantitation (LOQ), linearity, accuracy, precision, robustness and ruggedness were determined. LOQ values were achieved between 0.01 and 0.04%. Good linearity (r(2) > 0.99) was obtained ranging from LOQ to 150%. Recovery was verified for all impurities at concentrations ranging from LOQ to 150%. Hence, a newly developed RP-HPLC method was capable for well separation of all analytes with acceptable resolution and tailing factor.
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Affiliation(s)
- Dasari Purnachand
- Research and Development Centre, Suven Life Sciences Limited, Plot No.: 18, Phase-3; IDA, Jeedimetla, Hyderabad 500055, India
| | - Arava Veerareddy
- Research and Development Centre, Suven Life Sciences Limited, Plot No.: 18, Phase-3; IDA, Jeedimetla, Hyderabad 500055, India
| | | | - Ch V S L Kameswarrao
- Research and Development Centre, Suven Life Sciences Limited, Plot No.: 18, Phase-3; IDA, Jeedimetla, Hyderabad 500055, India
| | - Bethi Madhusudhanreddy
- Research and Development Centre, Suven Life Sciences Limited, Plot No.: 18, Phase-3; IDA, Jeedimetla, Hyderabad 500055, India
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Čolović J, Kalinić M, Vemić A, Erić S, Malenović A. Investigation into the phenomena affecting the retention behavior of basic analytes in chaotropic chromatography: Joint effects of the most relevant chromatographic factors and analytes’ molecular properties. J Chromatogr A 2015; 1425:150-7. [DOI: 10.1016/j.chroma.2015.11.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 11/06/2015] [Accepted: 11/08/2015] [Indexed: 11/17/2022]
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Zhong JJ, Liao N, Ding T, Ye X, Liu DH. Liquid chromatographic method for toxic biogenic amines in foods using a chaotropic salt. J Chromatogr A 2015; 1406:331-6. [DOI: 10.1016/j.chroma.2015.06.048] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 06/06/2015] [Accepted: 06/14/2015] [Indexed: 11/16/2022]
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Prediction of partition coefficients of guanidine hydrochloride in PEG–phosphate systems using neural networks developed with differential evolution algorithm. J IND ENG CHEM 2015. [DOI: 10.1016/j.jiec.2015.01.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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The influence of salt chaotropicity, column hydrophobicity and analytes’ molecular properties on the retention of pramipexole and its impurities. J Chromatogr A 2015; 1386:39-46. [DOI: 10.1016/j.chroma.2015.01.078] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 01/26/2015] [Accepted: 01/27/2015] [Indexed: 10/24/2022]
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Vemić A, Rakić T, Malenović A, Medenica M. Chaotropic salts in liquid chromatographic method development for the determination of pramipexole and its impurities following quality-by-design principles. J Pharm Biomed Anal 2015; 102:314-20. [DOI: 10.1016/j.jpba.2014.09.031] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 09/22/2014] [Accepted: 09/23/2014] [Indexed: 11/28/2022]
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Gumustas M, Uslu B, Ozkan SA, Aboul-Enein HY. Validated Stability-Indicating HPLC and UPLC Assay Methods for the Determination of Entacapone in Pharmaceutical Dosage Forms. Chromatographia 2014. [DOI: 10.1007/s10337-014-2758-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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The influence of inorganic salts with chaotropic properties on the chromatographic behavior of ropinirole and its two impurities. Talanta 2014; 123:122-7. [DOI: 10.1016/j.talanta.2014.02.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 01/29/2014] [Accepted: 02/04/2014] [Indexed: 11/24/2022]
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Colović J, Vemić A, Kostić N, Malenović A, Medenica M. Testing the capability of a polynomial-modified gaussian model in the description and simulation of chromatographic peaks of amlodipine and its impurity in ion-interaction chromatography. J Sep Sci 2014; 37:1797-804. [PMID: 24798430 DOI: 10.1002/jssc.201400206] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2014] [Revised: 04/17/2014] [Accepted: 04/21/2014] [Indexed: 11/07/2022]
Abstract
In this paper, the capability of a polynomial-modified Gaussian model to relate the peak shape of basic analytes, amlodipine, and its impurity A, with the change of chromatographic conditions was tested. For the accurate simulation of real chromatographic peaks the authors proposed the three-step procedure based on indirect modeling of peak width at 10% of peak height (W0.1), individual values of left-half width (A) and right-half width (B), number of theoretical plates (N), and tailing factor (Tf). The values of retention factors corresponding to the peak beginning (k(B)), peak apex (k(A)), peak ending (k(E)), and peak heights (H0) of the analytes were directly modeled. Then, the investigated experimental domain was divided to acquire a grid of appropriate density, which allowed the subsequent calculation of W0.1, A, B, N, and Tf. On the basis of the predicted results for Tf and N, as well as the defined criteria for the simulation the following conditions were selected: 33% acetonitrile/67% aqueous phase (55 mM perchloric acid, pH 2.2) at 40°C column temperature. Perfect agreement between predicted and experimental values was obtained confirming the ability of polynomial modified Gaussian model and three-step procedure to successfully simulate the real chromatograms in ion-interaction chromatography.
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Affiliation(s)
- Jelena Colović
- Department of Drug Analysis, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia
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