Determination of Attapulgite and Nifuroxazide in Pharmaceutical Formulations by Sequential Digital Derivative Spectrophotometry

Abstract A new method for the sequential determination of attapulgite and nifuroxazide in pharmaceutical formulations by first-and second-derivative spectrophotometry, respectively, has been developed. In order to obtain the optimal conditions for nifuroxazide stability, studies of solvent, light, and temperature effects were performed. The results show that a previous hydrolysis of 2 h in 1.0 × 10–1M NaOH solution is necessary in order to obtain stable compounds for analytical purposes. Subsequently, the first-and second-derivative spectra were evaluated directly in the same samples. The sequential determination of the drugs can be performed using the zero-crossing method; the attapulgite determination was carried out using the first derivative at 278.0 nm and the nifuroxazide determination, using the second derivative at 282.0 nm. The determination ranges were 5.7 × 10–6–1.0 × 10–4 and 3.7 × 10–8 –1.2 × 10–4M for attapulgite and nifuroxazide, respectively. Repeatability (relative standard deviation) values of 1.2 and 3.0% were observed for attapulgite and nifuroxazide, respectively. The ingredients commonly found in commercial pharmaceutical formulations do not interfere. The proposed method was applied to the determination of these drugs in tablets. Further, infrared spectroscopy and cyclic voltammetry studies were carried out in order to obtain knowledge of the decomposition products of nifuroxazide.

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Simultaneous Determination of Estradiol and Medroxyprogesterone Acetate in Pharmaceutical Formulations by Second-Derivative Spectrophotometry

Journal of AOAC International ◽

10.1093/jaoac/85.4.883 ◽

2002 ◽

Vol 85 (4) ◽

pp. 883-888 ◽

Cited By ~ 6

Author(s):

M Inés Toral ◽

César Soto ◽

Pablo Richter ◽

Ana E Tapai

Keyword(s):

Simultaneous Determination ◽

Medroxyprogesterone Acetate ◽

Signal To Noise Ratio ◽

Pharmaceutical Formulations ◽

Derivative Spectrophotometry ◽

Fast Method ◽

Second Derivative ◽

Zero Crossing ◽

Relative Standard

Abstract This paper reports a simple and fast method for the simultaneous determination of estradiol (ED) and medroxyprogesterone acetate (MP) in pharmaceutical formulations by second-derivative spectrophotometry. Methanol was used to extract the drugs from formulations, and subsequently the extracts were evaluated directly by derivative spectrophotometry. The drugs were determined simultaneously by using the graphic method at 297.4 nm for ED and the zero-crossing method at 273.4 nm for MP. If both compounds are present together in a sample, it is possible to quantitate one in the presence of the other. The best signal-to-noise ratio was found when the second derivative of the spectrum was used. The linear ranges for determination of the drugs were 4.7 × 10−6 to 1.6 × 10−4 and 7.2 × 10−6 to 2.0 × 10−4 mol/L for ED and MP, respectively. The ingredients commonly found in commercial pharmaceutical formulations do not interfere with the determination. Chemical and spectral variables were optimized for the determination of both analytes. Good levels of repeatability (relative standard deviation), 1.4 and 1.9%, were obtained for ED and MP, respectively. The proposed method was applied to the determination of these drugs in pharmaceutical formulations.

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Simultaneous Determination of N-Butylscopolamine and Oxazepam in Pharmaceutical Formulations by First-Order Digital Derivative Spectrophotometry

Journal of AOAC International ◽

10.1093/jaoac/88.4.1173 ◽

2005 ◽

Vol 88 (4) ◽

pp. 1173-1178 ◽

Cited By ~ 10

Author(s):

Maria Inés Toral ◽

Marcelo A Muñoz ◽

Sandra L Orellana

Keyword(s):

Standard Deviation ◽

Simultaneous Determination ◽

Relative Standard Deviation ◽

Pharmaceutical Formulations ◽

Derivative Spectrophotometry ◽

Simple Method ◽

Zero Crossing ◽

First Order ◽

Relative Standard

Abstract A simple method has been developed for the simultaneous determination of N-butylscopolamine bromide and oxazepam in pharmaceutical formulations using first-order digital derivative spectrophotometry. Acetonitrile was selected as the solvent in which both compounds showed well-defined bands. Both analytes showed good stability in this solvent when solutions of the analytes were exposed to light and temperatures between 20° and 80°C. The simultaneous determination of both drugs was performed by the zero-crossing method at 226.0 and 257.0 nm for N-butylscopolamine and oxazepam, respectively. The linear range of determination was found to be 2.5 × 10−7 to 8.0 × 10−5 mol/L for N-butylscopolamine and 7.1 × 10−8 to 8.0 × 10−5 mol/L for oxazepam. A very good level of repeatability (relative standard deviation) of 0.2% was observed for N-butylscopolamine and oxazepam. The ingredients commonly found in pharmaceutical formulations do not interfere. The proposed method was applied to the determination of these drugs in pharmaceutical formulations (capsules).

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Simultaneous Determination of Metoprolol-Hydrochlorothiazide and Propranolol-Hydrochlorothiazide in Combined Formulations by Derivative Spectroscopy

Journal of AOAC International ◽

10.1093/jaoac/80.2.325 ◽

1997 ◽

Vol 80 (2) ◽

pp. 325-330 ◽

Cited By ~ 14

Author(s):

Challapalli V N Prasad ◽

Vipin Bharadwaj ◽

Vidya Narsimhan ◽

Rama T Chowdhary ◽

Pyare Parimoo

Keyword(s):

Simultaneous Determination ◽

Second Derivative ◽

Zero Crossing ◽

Derivative Spectra ◽

Derivative Spectroscopy ◽

Naoh Solution ◽

Compensation Technique ◽

Second Derivative Spectra ◽

Crossing Point

Abstract A derivative spectrophotometric procedure was established for simultaneous determination of propranolol HCI (PP) with hydrochlorothiazide (HTZ) and metoprolol tartrate (MTP) with HTZ in tablet preparations. The method uses first- and second-derivative spectra of tablet extract in 0.01 N NaOH solution. Ratios of analyte concentrations in the mixture were determined by the compensation technique. The zero-crossing point (ZCP) was also used to estimate the amounts of PP and HTZ in the formulations, and results were compared with those from the compensation technique. The results were found to be precise and free from interferences.

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Application of Derivative Spectrophotometry for Simultaneous Determination of Quinapril and Hydrochlorothiazide in the Combination Tablets

Journal of AOAC International ◽

10.1093/jaoac/87.4.847 ◽

2004 ◽

Vol 87 (4) ◽

pp. 847-851 ◽

Cited By ~ 2

Author(s):

Dorota Kowalczuk ◽

Hanna Hopkała

Keyword(s):

Standard Deviation ◽

Simultaneous Determination ◽

Relative Standard Deviation ◽

Spectrophotometric Method ◽

Derivative Spectrophotometry ◽

Order Derivative ◽

Zero Crossing ◽

Relative Standard ◽

Separation Of Components

Abstract A new second-order-derivative spectrophotometric method using zero-crossing technique measures quinapril (QUI) and hydrochlorothiazide (HYD) in 2-component mixtures. The procedure does not require prior separation of components from the sample. QUI was determined at a wavelength of 211.6 nm (zero-crossing wavelength point of HYD). Similarly, HYD was measured at 270.8 nm (zero-crossing wavelength point of QUI). Calibration graphs were constructed over the concentration range of 4.0 to 24.0 μ/mL for QUI and 2.5 to 15.0 μg/mL for HYD. Detection and quantitation limits were 0.85 and 2.5 μg/mL for QUI and 0.12 and 0.4 μg/mL for HYD, respectively. The accuracy (recovery 100.5–102%), precision (relative standard deviation less than 3.5% for QUI and 1.5% for HYD), selectivity, and sensitivity of the elaborated methods were satisfactory. The proposed method was applied successfully for the determination of both drugs in QUI-HYD tablets.

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Simultaneous Determination of Dapsone and Pyrimethamine by Derivative Spectrophotometry in Pharmaceutical Formulations

Journal of AOAC International ◽

10.1093/jaoac/86.2.241 ◽

2003 ◽

Vol 86 (2) ◽

pp. 241-245 ◽

Cited By ~ 2

Author(s):

M Inés Toral ◽

Andrés Tassara ◽

César Soto ◽

Pablo Richter

Keyword(s):

Simultaneous Determination ◽

Signal To Noise Ratio ◽

Pharmaceutical Formulations ◽

Derivative Spectrophotometry ◽

Fast Method ◽

Signal To Noise ◽

Zero Crossing ◽

First Order ◽

First Derivative

Abstract A simple and fast method was developed for the simultaneous determination of dapsone and pyrimethamine by first-order digital derivative spectrophotometry. Acetonitrile was used as a solvent to extract the drugs from the pharmaceutical formulations, and the samples were subsequently evaluated directly by digital derivative spectrophotometry. The simultaneous determination of both drugs was performed by the zero-crossing method at 249.4 and 231.4 nm for dapsone and pyrimethamine, respectively. The best signal-to-noise ratio was obtained when the first derivative of the spectrum was used. The linear range of determination for the drugs was from 6.6 × 10−7 to 2.0 × 10−4 and from 2.5 × 10−6 to 2.0 × 10−4 mol/L for dapsone and pyrimethamine, respectively. The excipients of commercial pharmaceutical formulations did not interfere in the analysis. Chemical and spectral variables were optimized for determination of both analytes. A good level of repeatability, 0.6 and 1.7% for dapsone and pyrimethamine, respectively, was observed. The proposed method was applied for the simultaneous determination of both drugs in pharmaceutical formulations.

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Determination of Metformin Hydrochloride and Glyburide in an Antihyperglycemic Binary Mixture Using High-Performance Liquid Chromatographic-UV and Spectrometric Methods

Journal of AOAC International ◽

10.1093/jaoac/93.1.133 ◽

2010 ◽

Vol 93 (1) ◽

pp. 133-140 ◽

Cited By ~ 4

Author(s):

Hesham Salem

Keyword(s):

Binary Mixture ◽

High Performance ◽

Pharmaceutical Formulations ◽

High Performance Liquid Chromatographic ◽

Reversed Phase ◽

Metformin Hydrochloride ◽

Second Derivative ◽

Zero Crossing ◽

First Derivative

Abstract Three methods were developed for simultaneous determination of metformin hydrochloride and glyburide in an antihyperglycemic binary mixture without previous separation. In the first method, a reversed-phase HPLC column with acetonitrilewater (60 + 40, v/v) mobile phase at 0.9 mL/min flow rate was used to separate both compounds, with UV detection at 254 nm. Linearity was obtained in the concentration range of 0.060.24 µg/mL for glyburide and 1.56.0 µg/mL for metformin hydrochloride. The second method depended on first- and second-derivative UV spectrometry with zero-crossing measurements. The first-derivative amplitude at 261 nm was selected for the assay of glyburide, and the second-derivative amplitude at 235 nm was selected for the assay of metformin hydrochloride. The third method depended on measuring the first derivative of the ratio-spectra at 241 nm for glyburide and 227 nm for metformin hydrochloride. For the second and third methods, Beer's law was obeyed in the range of 1055 µg/mL for glyburide and 20200 µg/mL for metformin. The proposed methods were extensively validated and applied for the analysis of some pharmaceutical formulations containing binary mixtures of the mentioned drugs.

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Simultaneous Determination of Cu(II) and Ag(I) on SP Sephadex C25 as Complexes with 1-Phenyl-1,2-Propanedione-2-Oximethiosemicarbazone by Derivative Spectrophotometry

Journal of AOAC International ◽

10.1093/jaoac/90.6.1695 ◽

2007 ◽

Vol 90 (6) ◽

pp. 1695-1700 ◽

Cited By ~ 2

Author(s):

Libby Morales ◽

M Inés Toral

Keyword(s):

Simultaneous Determination ◽

Inductively Coupled Plasma ◽

Solid Phase ◽

Industrial Effluents ◽

Derivative Spectrophotometry ◽

Zero Crossing ◽

Inductively Coupled ◽

Relative Standard ◽

Stirring Time

Abstract The proposed method was based on retention and preconcentration of the complexes Cu(II)PPDOT and Ag(I)PPDOT on a solid phase in acid medium. The complexes were quantitatively retained in the cation exchanger SP Sephadex C25, and the analytical measurements were executed directly in the solid phase by derivative spectrophotometry. In this simultaneous determination, the second derivative and the zero crossing method were used. The determination of copper and silver was carried out to 321.0 and 427.0 nm, respectively. In order to obtain quantitative recoveries of the metal ions, various experimental analytical parameters, such as pH, stirring time, volume, and amount of solid phase, were optimized. The effect of interfering ions on the determination was described. The recovery values for Cu(II) and Ag(I) were found to be >98, and the relative standard deviation was 2. The detection limits (3 criterion) for Cu(II) and Ag(I) were found to be 0.9 108 and 13 108 M, respectively. The developed method was utilized for preconcentration and determination of Cu(II) and Ag(I) in industrial effluents and natural water samples. The results were consistent with those provided by inductively coupled plasma/mass spectrometry.

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Simultaneous determination of compounds in Septalen® pellets by derivative spectrophotometry

Journal of the Serbian Chemical Society ◽

10.2298/jsc0006339m ◽

2000 ◽

Vol 65 (5-6) ◽

pp. 339-344 ◽

Cited By ~ 6

Author(s):

Mirjana Medenica ◽

Darko Ivanovic ◽

Andjelija Malenovic

Keyword(s):

Simultaneous Determination ◽

Regression Coefficient ◽

Correlation Coefficients ◽

The Other ◽

Second Derivative ◽

Zero Crossing ◽

Derivative Spectra ◽

Second Derivative Spectra ◽

Cetrimonium Bromide

In this paper, a second-derivative spectrophotometric method of assaying Septalen ? pellets (Krka, Novo Mesto, Slovenia), which contain lidocaine 1 mg, and cetrimoniumbromide 2mg, is described. Lidocaine, 2-(diethylamino)-N-(2,6-dimethyl- phenyl)-acetamide, is a local anesthetic with pronounced antiarhythmic and anticonvulsant properties. Cetrimoniumbromide, N,N,N-trimethyl-l-hexadecanaminium bromide, is a topical antiseptic and cleansing agent. Lidocaine was determined at 250 nm using the "zero crossing" technique because the signals of centrimonium bromide and the colour ingredient are zero at this wavelength. Cetrimonium bromide was determined by correction of the peak amplitude at 215 nm according to lidocaine. In choosing the optimal magnitudes for the simultaneous determination of both drugs, the following criteria were considered: (1) the linearity of the calibration graphs as given by the correlation coefficients, (2) the intercept, (3) the sensitivity as given by the regression coefficient, (4) the degree of interference in the derivative measurement by the presence of the other compound, as given by the relative percent error and by the relative recovery, and (5) the reproducibility, as given by the coefficient of variation, calculated by recording the second-derivative spectra.

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Second-derivative spectrophotometry for the analysis of simvastatin in polymeric nanocapsules

Drug Analytical Research ◽

10.22456/2527-2616.98057 ◽

2019 ◽

Vol 3 (2) ◽

pp. 12-17

Author(s):

Patrícia Gomes ◽

Carla M. U. Negretto ◽

Zanandria B. Naisinger ◽

Ricardo Lorenzoni ◽

Nathalie Ribeiro Wingert ◽

...

Keyword(s):

Derivative Spectrophotometry ◽

Sample Analysis ◽

Zero Crossing ◽

Standard Curve ◽

Adequate Response ◽

Specificity Test ◽

Relative Standard ◽

Double Beam ◽

Polymeric Nanocapsules

Conventional spectrophotometry methods are very susceptible to the presence of interferences in complex mixtures such as nanoparticules, requiring prior treatment or extraction of the analyte, and not always providing an adequate response. Derivative spectrophotometry method is capable to eliminate its interference; it is an alternative method for drugs determination in complex matrices. This work investigated the utility of derivate spectrophotometry in assay of simvastatin in polymeric nanocapsules (SIVNC). Shimadzu® UV-1650 double-beam spectrophotometer with 1.0 cm quartz cells was used in this study. The second-order derivative spectrum was obtained employing Δλ=20,000 nm and scaling factor=9.0. The determinations were made at 239 nm (2D239) by zero-crossing method. 2D239 method was validated employing the parameters: specificity, linearity, robustness, precision and accuracy. Results: The specificity test showed there was no interference of constituents commonly found in SIVNC formulation in 2D239. The standard curve showed a correlation coefficient of 0.994. The robustness was evaluated by small changes in the conditions of sample analysis and however, no significant changes were observed regarding drug quantitation. The precision was demonstrated by relative standard deviation (RSD) of intra-day (RSD=1.61-3.76) and inter-day studies (RSD=2.32). The recovery test resulted in an average of 100.66%, which confirmed the accuracy of the method. The procedure was simple and rapid; therefore this technique offers an alternative for determination of SIVNC without interferences.

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Determination of phenylephrine hydrochloride and Amoxicillin in binary mixture using Derivative Spectrophotometry methods

International Journal of Pharmaceutical Quality Assurance ◽

10.25258/ijpqa.10.3.10 ◽

2019 ◽

Vol 10 (03) ◽

Author(s):

Aseel M Aljeboree ◽

Abbas Noor Alshirifi

Keyword(s):

Binary Mixture ◽

Pharmaceutical Formulations ◽

Mutual Interference ◽

Derivative Spectrophotometry ◽

Simultaneous Estimation ◽

Second Derivative ◽

Derivative Spectrum ◽

Phenylephrine Hydrochloride ◽

First Derivative

A simple, precise and economical procedure for the simultaneous estimation of Phenylephrine Hydrochloride (PHE) and Amoxicillin (AMX) in formulation has been developed. The absorbance values of first derivative spectrum 228,258 nm andm 241 nm and second derivative spectrum 238, 277 nm and 226 nm was used for the estimation of PHE and AMX, respectively without mutual interference. This method obeyed beerand#39;s law in the concentration range mixing of 2-150mgL -1 PHE with 0,20,100 mgL -1 AMX and 2-240 mgL -1 AMX with 0,20,100 mgL -1 PHE and the second derivative depends on first derivative of the ratios spectra. The proposed methods are extensively validated. All the described methods can be readily utilized for analysis of pharmaceutical formulations.

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