Accurate and sensitive spectrofluorimetric method was developed for determination of diiodohydrox... more Accurate and sensitive spectrofluorimetric method was developed for determination of diiodohydroxyquinoline in presence of metronidazole. In this method the native fluorescence of diiodohydroxyquinoline in water solvent at λ =495 nm when excitation was at 250 nm is used for its determination. Linear correlation was obtained in theconcentration range of 400 to 900 ng mL-1. The proposed method was successfully applied for determination ofdiiodohydroxyquinoline in bulk powder with mean accuracy of 100.21±1.13 or in spiked human plasma with mean accuracy of 100.53±1.42 without interference of metronidazole. Keywords: spectrofluorimetry, Diiodohydroxyquinoline and Metronidazole.
Two robust and selective stability-indicating chromatographic methods were developed and validate... more Two robust and selective stability-indicating chromatographic methods were developed and validated for the determination of metolazone in drug substance and pharmaceutical dosage form in the presence of its degradation products. The HPLC method employed a Kromasil C18 (250 × 4.6,5 μm) column and a mobile phase of acetonitrile: 0.2% orthophosphoric acid (32:68 v/v) at a flow rate 2 mL/min and detection at 238 nm. The separation was performed in HPLC isocratic mode. The robustness of the suggested method was assessed using the Plackett–Burman design, parameters affecting system suitability were established and non-significant intervals for the significant parameters were considered. The HPTLC method employed Nano-SIL-20 UV254 HPTLC plates as adsorbent, ethyl acetate: toluene: acetic acid solution (4:4:0.5, v/v/v), as a developing solvent system and densitometric detection at 238 nm. Metolazone was exposed to different stress conditions, including acid and alkaline hydrolysis and oxida...
Four sensitive, selective and precise stability indicating methods for the determination of isopr... more Four sensitive, selective and precise stability indicating methods for the determination of isopropamide iodide (ISO) and trifluoperazine hydrochloride (TPZ) in their binary mixture and in presence of trifluoperazine oxidative degradate (OXD). Method A is a derivative spectrophotometric one, where ISO was determined by first derivative (D1) at 226.4 nm while TPZ was determined by second derivative (D2) at 270.2 nm. Method B is the first derivative of the ratio spectra (DD1) spectrophotometric method, ISO can be determined by measuring the peak amplitude at 227.4 nm using 5 µg mL−1 of OXD as a divisor, while TPZ can be determined by measuring the peak amplitude at 249.2 and 261.4 nm using 15 µg mL−1 of ISO as a divisor. Method C is the isoabsorptive spectrophotometric method. This method allows determination of ISO and TPZ in their binary mixture by measuring total concentration of ISO and TPZ at their isoabsorptive point at λ229.8 nm (Aiso1) while TPZ concentration alone can be dete...
Five simple, accurate, precise, and economical spectrophotometric methods have been developed for... more Five simple, accurate, precise, and economical spectrophotometric methods have been developed for thedetermination of cefixime trihydrate (CFX) in the presence of its acid and alkali degradation products without prior separation. In the first method, secondderivative (2D) and first derivative (1D) spectrophotometry was applied to the absorption spectra of CFX and its acid (2D) or alkali (1D) degradation products by measuring the amplitude at 289 and 308 nm, respectively. The second method was a first derivative (1DD) ratio spectrophotometric method where the peak amplitudes were measured at 311 nm in presence of the acid degradation product, and 273 and 306 nm in presence of its alkali degradation product. The third method was ratio subtraction spectrophotometry where the drug is determined at 286 nm in laboratory-prepared mixtures of CFX and its acid or alkali degradation product. The fourth method was based on dualwavelength analysis; two wavelengths were selected at which the abs...
Ophthalmic pharmaceutical preparation containing antazoline (ANT) and tetryzoline (TET) is pres... more Ophthalmic pharmaceutical preparation containing antazoline (ANT) and tetryzoline (TET) is prescribed widely as an over the counter medication for allergic conjunctivitis treatment. Development of a selective, simple and environmentally friendly thin-layer chromatographic method established to determine both ANT and TET in their pure forms, pharmaceutical formulation and spiked aqueous humor samples. By using silica gel plates and means of a developing system consists of ethyl acetate:ethanol (5:5, by volume), the studied drugs separation was achieved, and scanning was carried out at 220.0 nm for the separated bands with a 0.2–18.0 μg/band concentration range for each of ANT and TET. Standard addition technique application was carried out to determine the proposed method validity. Statistical comparison was made between the proposed method and the official methods ANT and TET showing no significant difference concerning accuracy and precision. Furthermore, greenness profile assess...
Three sensitive, selective and precise stability-indicating methods for the determination of the ... more Three sensitive, selective and precise stability-indicating methods for the determination of the anti-Alzheimer's drug, rivastigmine hydrogen tartrate (RIV) in the presence of its alkaline degradation product (major metabolite, NAP 226-90) and in pharmaceutical formulation were developed and validated. The first method is a second derivative (D(2)) spectrophotometric one, which allows the determination of RIV in the presence of its degradate at 262 nm (corresponding to zero crossing of the degradate) over a concentration range of 50-500 microg/ml with mean percentage recovery 100.18 +/- 0.628. The second method is the first derivative of the ratio spectra (DD(1)) by measuring the peak amplitude at 272 nm over the same concentration range as (D(2)) spectrophotometric method, with mean percentage recovery 99.97 +/- 0.641. The third method is a TLC-densitometric one, where RIV was separated from its degradate on silica gel plates using methanol:butanol:H(2)O:ammonia (5:4:1:0.01 v:v:v) as a developing system. This method depends on the quantitative densitometric evaluation of thin layer chromatogram of RIV at 263 nm over a concentration range of 20-160 microg/spot, with mean percentage recovery 100.19 +/- 1.344. The selectivity of the proposed methods was tested using laboratory-prepared mixtures. The proposed methods have been successfully applied to the analysis of RIV in pharmaceutical dosage forms without interference from other dosage form additives and the results were statistically compared with reference method.
Accurate and sensitive spectrofluorimetric method was developed for determination of diiodohydrox... more Accurate and sensitive spectrofluorimetric method was developed for determination of diiodohydroxyquinoline in presence of metronidazole. In this method the native fluorescence of diiodohydroxyquinoline in water solvent at λ =495 nm when excitation was at 250 nm is used for its determination. Linear correlation was obtained in theconcentration range of 400 to 900 ng mL-1. The proposed method was successfully applied for determination ofdiiodohydroxyquinoline in bulk powder with mean accuracy of 100.21±1.13 or in spiked human plasma with mean accuracy of 100.53±1.42 without interference of metronidazole. Keywords: spectrofluorimetry, Diiodohydroxyquinoline and Metronidazole.
Two robust and selective stability-indicating chromatographic methods were developed and validate... more Two robust and selective stability-indicating chromatographic methods were developed and validated for the determination of metolazone in drug substance and pharmaceutical dosage form in the presence of its degradation products. The HPLC method employed a Kromasil C18 (250 × 4.6,5 μm) column and a mobile phase of acetonitrile: 0.2% orthophosphoric acid (32:68 v/v) at a flow rate 2 mL/min and detection at 238 nm. The separation was performed in HPLC isocratic mode. The robustness of the suggested method was assessed using the Plackett–Burman design, parameters affecting system suitability were established and non-significant intervals for the significant parameters were considered. The HPTLC method employed Nano-SIL-20 UV254 HPTLC plates as adsorbent, ethyl acetate: toluene: acetic acid solution (4:4:0.5, v/v/v), as a developing solvent system and densitometric detection at 238 nm. Metolazone was exposed to different stress conditions, including acid and alkaline hydrolysis and oxida...
Four sensitive, selective and precise stability indicating methods for the determination of isopr... more Four sensitive, selective and precise stability indicating methods for the determination of isopropamide iodide (ISO) and trifluoperazine hydrochloride (TPZ) in their binary mixture and in presence of trifluoperazine oxidative degradate (OXD). Method A is a derivative spectrophotometric one, where ISO was determined by first derivative (D1) at 226.4 nm while TPZ was determined by second derivative (D2) at 270.2 nm. Method B is the first derivative of the ratio spectra (DD1) spectrophotometric method, ISO can be determined by measuring the peak amplitude at 227.4 nm using 5 µg mL−1 of OXD as a divisor, while TPZ can be determined by measuring the peak amplitude at 249.2 and 261.4 nm using 15 µg mL−1 of ISO as a divisor. Method C is the isoabsorptive spectrophotometric method. This method allows determination of ISO and TPZ in their binary mixture by measuring total concentration of ISO and TPZ at their isoabsorptive point at λ229.8 nm (Aiso1) while TPZ concentration alone can be dete...
Five simple, accurate, precise, and economical spectrophotometric methods have been developed for... more Five simple, accurate, precise, and economical spectrophotometric methods have been developed for thedetermination of cefixime trihydrate (CFX) in the presence of its acid and alkali degradation products without prior separation. In the first method, secondderivative (2D) and first derivative (1D) spectrophotometry was applied to the absorption spectra of CFX and its acid (2D) or alkali (1D) degradation products by measuring the amplitude at 289 and 308 nm, respectively. The second method was a first derivative (1DD) ratio spectrophotometric method where the peak amplitudes were measured at 311 nm in presence of the acid degradation product, and 273 and 306 nm in presence of its alkali degradation product. The third method was ratio subtraction spectrophotometry where the drug is determined at 286 nm in laboratory-prepared mixtures of CFX and its acid or alkali degradation product. The fourth method was based on dualwavelength analysis; two wavelengths were selected at which the abs...
Ophthalmic pharmaceutical preparation containing antazoline (ANT) and tetryzoline (TET) is pres... more Ophthalmic pharmaceutical preparation containing antazoline (ANT) and tetryzoline (TET) is prescribed widely as an over the counter medication for allergic conjunctivitis treatment. Development of a selective, simple and environmentally friendly thin-layer chromatographic method established to determine both ANT and TET in their pure forms, pharmaceutical formulation and spiked aqueous humor samples. By using silica gel plates and means of a developing system consists of ethyl acetate:ethanol (5:5, by volume), the studied drugs separation was achieved, and scanning was carried out at 220.0 nm for the separated bands with a 0.2–18.0 μg/band concentration range for each of ANT and TET. Standard addition technique application was carried out to determine the proposed method validity. Statistical comparison was made between the proposed method and the official methods ANT and TET showing no significant difference concerning accuracy and precision. Furthermore, greenness profile assess...
Three sensitive, selective and precise stability-indicating methods for the determination of the ... more Three sensitive, selective and precise stability-indicating methods for the determination of the anti-Alzheimer's drug, rivastigmine hydrogen tartrate (RIV) in the presence of its alkaline degradation product (major metabolite, NAP 226-90) and in pharmaceutical formulation were developed and validated. The first method is a second derivative (D(2)) spectrophotometric one, which allows the determination of RIV in the presence of its degradate at 262 nm (corresponding to zero crossing of the degradate) over a concentration range of 50-500 microg/ml with mean percentage recovery 100.18 +/- 0.628. The second method is the first derivative of the ratio spectra (DD(1)) by measuring the peak amplitude at 272 nm over the same concentration range as (D(2)) spectrophotometric method, with mean percentage recovery 99.97 +/- 0.641. The third method is a TLC-densitometric one, where RIV was separated from its degradate on silica gel plates using methanol:butanol:H(2)O:ammonia (5:4:1:0.01 v:v:v) as a developing system. This method depends on the quantitative densitometric evaluation of thin layer chromatogram of RIV at 263 nm over a concentration range of 20-160 microg/spot, with mean percentage recovery 100.19 +/- 1.344. The selectivity of the proposed methods was tested using laboratory-prepared mixtures. The proposed methods have been successfully applied to the analysis of RIV in pharmaceutical dosage forms without interference from other dosage form additives and the results were statistically compared with reference method.
Uploads
Papers by Mohamed AbdelKawy