Practical Approach for the Determination of Response Factors of Impurities in Drugs by HPLC

For the determination of accurate quantity of impurities in the samples authentic impurity standards or response factors at a given wavelength must be known. In the presented work a convenient method for determination of relative response factors of impurities has been described without using an authentic impurities standard. An approach for the determination of response factors of the impurities where impurity standard is physically not available was developed and verified using different approaches. One such method was developed and verified by RP-HPLC using Cosmosil C18 MS-II column at UV 238 nm. Two different approaches were employed and the verification of correctness of approach was done using a known related substance of known response factor.

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Determination of relative response factors for chromatographic investigations using NMR spectrometry

Journal of Pharmaceutical and Biomedical Analysis ◽

10.1016/j.jpba.2009.02.027 ◽

2009 ◽

Vol 49 (5) ◽

pp. 1261-1265 ◽

Cited By ~ 29

Author(s):

Gregory K. Webster ◽

Ian Marsden ◽

Cynthia A. Pommerening ◽

Christina M. Tyrakowski ◽

Brian Tobias

Keyword(s):

Response Factors ◽

Relative Response ◽

Nmr Spectrometry

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Determination of individual nonylphenol isomers in water samples by using relative response factor method

BUNSEKI KAGAKU ◽

10.2116/bunsekikagaku.53.1139 ◽

2004 ◽

Vol 53 (10) ◽

pp. 1139-1147 ◽

Cited By ~ 7

Author(s):

Yuichi HORII ◽

Takao KATASE ◽

Yun-Seok KIM ◽

Nobuyoshi YAMASHITA

Keyword(s):

Water Samples ◽

Response Factor ◽

Relative Response Factor ◽

Factor Method ◽

Relative Response

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Characterization and relative response factor determination of process related impurity in Naproxen by nuclear magnetic resonance spectroscopy

Journal of Pharmaceutical and Biomedical Analysis ◽

10.1016/j.jpba.2011.06.003 ◽

2011 ◽

Vol 56 (3) ◽

pp. 484-490 ◽

Cited By ~ 15

Author(s):

Md. Yakub Iqbal ◽

K.M.V. Narayana Rao ◽

G. Sridhar ◽

P. Padmanabha Raju ◽

Girish R. Deshpande ◽

...

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Magnetic Resonance Spectroscopy ◽

Nuclear Magnetic Resonance Spectroscopy ◽

Resonance Spectroscopy ◽

Response Factor ◽

Relative Response Factor ◽

Relative Response ◽

Nuclear Magnetic

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Determination of Triacylglycerols by HTGC-FID as a Sensitive Tool for the Identification of Rapeseed and Olive Oil Adulteration

Molecules ◽

10.3390/molecules25173881 ◽

2020 ◽

Vol 25 (17) ◽

pp. 3881

Author(s):

Ying Qian ◽

Magdalena Rudzińska ◽

Anna Grygier ◽

Roman Przybylski

Keyword(s):

Olive Oil ◽

Rapeseed Oil ◽

Edible Oils ◽

Response Factor ◽

Limits Of Detection ◽

Relative Response Factor ◽

Relative Response ◽

Sensitive Tool

Triacylglycerols (TGs) are the most common compounds in food lipids, accounting for 95% of the weight of edible oils. The aim of this study was to scrutinize a procedure for quantitatively assessing possible adulteration of olive and rapeseed oil through GC-FID analysis of TGs. The recovery of TG standards ranged from 21% to 148%, and the relative response factor (RRF) ranged from 0.42 to 2.28. The limits of detection were in the range of 0.001 to 0.330 µg/mL, and the limits of quantitation from 0.001 to 1.000 µg/mL. The validated method was used to determine the TGs in olive oil (OO), refined rapeseed oil (RRO), and their blends. Eight TGs were detected in refined rapeseed oil, and 10 in olive oil. The addition of 1% of olive oil to rapeseed oil or vice versa can be detected using this method. Three triacylglycerols were pinpointed as indicators of adulteration of rapeseed oil with olive oil (PPO, PPL, PSO). The method described here can be used for controlling the quality of these oils.

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Determination of relative response factors of the opium alkaloids with HPLC-DAD

Macedonian Pharmaceutical Bulletin ◽

10.33320/maced.pharm.bull.2011.57.004 ◽

2011 ◽

Vol 57 ◽

pp. 37-41

Author(s):

Jelena Acevska ◽

Gjoshe Stefkov ◽

Natalija Nakov ◽

Marija Karapandzova ◽

Svetlana Kulevanova ◽

...

Keyword(s):

Regression Analysis ◽

High Performance ◽

Ph Value ◽

Gradient Elution ◽

Reversed Phase ◽

Array Detector ◽

Response Factors ◽

Opium Alkaloids ◽

Relative Response

In this work, a convenient method for determination of relative UV response factors (RRFs) of morphine, codeine, thebaine, oripavine, noscapine and papaverine by high performance liquid chromatography (HPLC) equipped with a diode array detector (DAD) was presented. Pholcodine was selected as the reference compound for calculating the relative response factors of the alkaloids. The separation of all seven compounds was obtained with optimized gradient elution with high pH value of the mobile phase on a reversed phase column with bidentate C18-C18 bonding technology. The RRFs of the alkaloids were determinate by three different approaches: ‘regression analysis/mass concentration’, ‘regression analysis/molar concentration’and ‘detector sensitivity’ approaches. The ‘regression analysis/molar concentration’ approach gave the accurate approximation of the exact amount of the substance that enters in the detector and the statistically relevant calculation includes several points of different concentrations (at least five), which makes this approach most advantageous one. This method is suitable for quality assessment of the standardised opium dry extract, raw opium and standardised opium tincture by quantitative analysis of not only morphine and codeine as indicated in the respective European Pharmacopoeia monographs, but as well as the major impurities that originate from opium poppy Papaver somniferum L. (Papaveraceae).

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