Spectrophotometry Determination of Amitriptyline-HCl in Pure and Pharmaceutical Preparations.

ABSTRACT

Amitriptyline-HCl reacts with ammonium molybdate in concentrated sulphuric acid after heating for 20 min. at 100°C to give a green colour having maximum absorbance at 660 nm. The reaction is selective for amitriptyline with 0.01 mg/10ml as visual limit of identification and provides a basis for a new spectrophotometric determination. The reaction obeys Beer's law from 0.01 mg to 1.4 mg/10ml of amitriptyline-HCl and the relative standard deviation is 0.35%. The quantitative assessment of tolerable amount of other drags is also studied.     

气相色谱法与高效液相色谱法测定琥珀酸索利那新原料药中的残留溶剂

建立了测定琥珀酸索利那新原料药中残留溶剂甲醇、乙醇、丙酮、叔丁醇、乙酸乙酯、正庚烷、石油醚、甲苯的气相色谱法和测定吡啶的高效液相色谱法。气相色谱法中以N,N-二甲基甲酰胺为溶剂,以TR-5毛细管柱为分离柱,采用氢火焰离子化检测器。高效液相色谱法中以AQC18色谱柱为分离柱,以50mmol·L-1磷酸氢二钠水溶液(含0.1%三乙胺,pH为7.6)-乙腈(1+1)为流动相,检测波长为254nm。9种溶剂的质量浓度在一定范围内呈线性,吡啶的检出限为0.01mg·L-1,其余8种溶剂的检出限在1.17~5.00 mg·L-1之间,加标回收率在86.3%~101%之间,相对标准偏差(n=6)在2.4%~6.3%之间。     

Determination of Bretylium in Pharmaceutical Dosage Forms

Abstract

A simple, high-pressure liquid chromatographic method for determination of bretylium in pharmaceutical dosage forms is described. The sensitivity of the method is 50 ng with high reproducibility. Exogenous additives from injection, infusion or tablet dosage forms do not interfere with the assay. An increase in the pH of the sample, however, caused a decrease in the peak height of bretylium. Bretylium is a chemically stable compound. Under conditions of either 1.5 N hydrochloric acid, nitric acid, or sodium hydroxide at 25°C and 100°C for a period of up to 48 hours did not influence the outcome of the assay.     

间接分光光度法测定药物中的抗坏血酸

利用抗坏血酸对铁（Ⅲ）－４－（２－苯并噻唑偶氮）邻苯二酚－乳化剂ＯＰ络合物的还原作用生成铁（Ⅱ）－４－（２－苯并噻唑偶氮）邻苯二酚－乳化剂ＯＰ络合物,分光光度法间接测定抗坏血酸,同时测定了反应比,试验表明拟定方法方便快捷,准确可靠     

Determination of Acetylcysteine in Pharmaceutical Samples by Silicomolybdenum Blue Spectrophotometry

An accurate and fast spectrophotometric method for the determination of acetylcysteine by silicomolybdenum blue has been established. The various effect factors on the determination of acetylcysteine by silicomolybdenum blue spectrophotometry are investigated in detail. The results show that under the optimum reaction conditions, SiO₃^2‐ reacts with Mo₇O₂₄^6‐ to form silicon molybdenum heteropoly acid (H₄Si(Mo₃O₁₀)₄). Then H₄Si(Mo₃O₁₀)₄ is reduced by hydrosulfuryl (‐SH) in acetylcysteine to form silicomolybdenum blue (H₄Si(Mo₃O₁₀)₂(Mo₃O₉)₂). The absorbance of silicomolybdenum blue is measured at the maximal absorption wavelength of 735 nm, and the content of acetylcysteine can be calculated based on this absorbance. A good linear relationship is obtained between the absorbance of silicomolybdenum blue and the concentration of acetylcysteine in the range of 5.040∼25.20 μg⋅mL^‐1. The linear regression equation is A = 0.0272 + 21.484C (mg⋅mL^‐1), with a linear correlation coefficient of 0.9995. This proposed method has been successfully applied to the determination of acetylcysteine in pharmaceutical samples, and the results agree well with those obtained by pharmacopoeial method.     

Indirect Determination of Organic Compounds by Atomic Absorption Spectrophotometry: The Study of Vitamin B12 in Pharmaceutical Dosage Forms

Abstract

A method for the determination of vitamin B₁₂ in pharmaceutical dosage forms is presented. The method involves, dissolution of the vitamin B₁₂ and subsequent determination of the complexed cobalt by atomic absorption spectrophotometry. The method is both rapid and sensitive giving applications to quality, control of this type of formulation.     

Determination of Cinnarizine in Pure and Pharmaceutical Formulations

Two simple, rapid and sensitive extractive spectrophotometric methods have been developed for the assay of cinnarizine (CNR) in pure and pharmaceutical formulations. The methods are based on the formation of chloroform soluble ion‐association complexes of CNR with thymol blue (TB) and with cresol red (CR) inNaOAc‐AcOH buffer of pH 3.6 for TB and in KCl‐HCl buffer of pH 1.6 for CR with absorption maxima at 405 nm and at 403 nm for TB and CR, respectively. Reaction conditions were optimized to obtain the maximum color intensity. The systems obeyed Beer's law in the range of 0.6–15.8 and 0.8–16.6 μg mL^?1 for TB and CR, respectively. Various analytical parameters have been evaluated and the results have been validated by statistical data.     

Determination of Ranitidine Hydrochloride in Pharmaceutical Preparations by Ultraviolet and Visible Spectrophotometry

Abstract

Ranitidine hydrochloride in tablets (T) and injections (I) was determined by ultraviolet spectrophotometry (UVS) at 313 nm and visible spectrophotometry (VISS) at 615 nm, after reaction with 3-methyl-2-benzothiazolinone hydrazone hydrochloride (MBTH) and ferric chloride. For UVS, Beer's law was obeyed in the range 5.0 – 18.0 μg/mL. The coefficients of variation (CV) for the samples T were 0.36% and 0.71% and for the samples I were 0.51% and 0.24%. The recovery average (RA) was 99.88%. For UVS, Beer's law was observed in the range 1.44 – 5.76 μg/mL. The CV for T were 0.72% and 0.59%, and for I were 0.53% and 0.61%. The RA was 99.39%. The precision and accuracy of the two methods were compared.     

LC-DAD Determination of Fleroxacin in Bulk and Pharmaceutical Dosage Forms

Fleroxacin is a third generation fluoroquinolone with broad spectrum antibacterial activity. In this work an LC-DAD method for the analysis of fleroxacin was developed and validated using UV detection at 286 nm. The method was validated for linearity, precision, robustness, LOD, LOQ, specificity and accuracy at concentrations of 0.2–20.0 μg mL⁻¹ and r ² = 1. The LOD and LOQ were 0.059 and 0.197 μg, respectively, the recoveries were 99.92–102.0% and the CV was less than 2.0%. The LC-DAD validated method provided analytical sensitivity, specificity and reproducibility suitable for quality control analysis.

     

Spectrophotometric Determination of Methyldopa in Pure and Pharmaceutical Preparations

Abstract

Methyldopa reacts with barbituric acid to give a red colour having maximum absorbance at 540 nm. The reaction is selective for methyldopa with 0.01 mg/ml as visual limit of quantitation and provides a basis for a new spectrophotometric determination. The colour reaction obeys Beer's Law from 0.1 mg to 2.5 mg/10 ml of methyldopa and the relative standard deviation is 1.1%. The quantitative assessment of tolerable amount of other drugs is also studied.     

Spectrophotometric Determination of Lisinopril in Pure and Pharmaceutical Formulations

An accurate, simple, fast, and cheap spectrophotometric method has been developed for the determination of lisinopril in pharmaceutical pure and dosage forms. The method is based on the reaction of ninhydrin with primary amine present in the lisinopril in the presence of DMF. This reaction produces a greenish blue colored product which absorbs maximally at 600 nm. Beer's law was obeyed in the range of 10–150 μg/mL with molar absorptivity of 4.083 × 10³ L mole^?1 cm^?1. The effects of variables such as temperature, heating time, concentration of color producing reagent, and stability of color were investigated to optimize the procedure. The results are validated statistically. The proposed method was applied to commercially available tablets, and the results were statistically compared with the official potentiometric method.     

Spectrophotometric Determination of Naproxen in Pure and Pharmaceutical Preparations

ABSTRACT

Naproxen reacts with 1-naphthylamine and sodium nitrite to give an orangish red colour having maximum absorbance at 460-480 nm (working wavelength 480 nm). The reaction is selective for naproxen with 0.001 mg/ml as visual limit of quantitation and provides a basis for a new spectrophotometric determination. The reaction obeys Beer's law from 0.01mg to 6.5 mg/10ml of naproxen and the relative standard deviation is 1.5%. The quantitative assessment of tolerable amount of other drugs is also studied.     

Determination of Carbamazepine in Pharmaceutical Dosage Form Using GC-FID

The present work describes the methodology and validation of gas chromatography with flame ionization detection (GC-FID) for the determination of carbamazepine with internal standard (diazepam) in pharmaceutical preparations. The method was linear from 2–30 μg mL⁻¹. The RSD values for precision was less than 9%, accuracy (relative error) was better than 11% (n = 6). The developed method was successfully applied for the assay of pharmaceutical dosage forms which do not require any preliminary separation or treatment of the samples. The RSD values for Tegretol^® tablets (200 mg) and Karberol^® tablets (200 mg) was found to be 4.03 and 3.25%, respectively. The results obtained from this method were compared with the reference method (LC) reported in literature and no significant difference was found statistically.

     

LC-DAD Determination of Fleroxacin in Bulk and Pharmaceutical Dosage Forms

Fleroxacin is a third generation fluoroquinolone with broad spectrum antibacterial activity. In this work an LC-DAD method for the analysis of fleroxacin was developed and validated using UV detection at 286 nm. The method was validated for linearity, precision, robustness, LOD, LOQ, specificity and accuracy at concentrations of 0.2–20.0 μg mL⁻¹ and r ² = 1. The LOD and LOQ were 0.059 and 0.197 μg, respectively, the recoveries were 99.92–102.0% and the CV was less than 2.0%. The LC-DAD validated method provided analytical sensitivity, specificity and reproducibility suitable for quality control analysis.     

手性固定相高效液相色谱法同时测定琥珀酸索利那新原料药中对映异构体和非对映异构体

以手性填料色谱柱为固定相,建立了同时测定琥珀酸索利那新原料药中对映异构体和非对映异构体的高效液相色谱法。分别以Daicel CHIRALPAKAD-H手性色谱柱、Daicel CHIRALCELOJ-H手性色谱柱、研创SCDP52546手性色谱柱、研创RC-OD52546手性色谱柱为分离柱,进行色谱柱筛选,并考察了不同检测波长、柱温及流动相体系对对映异构体和非对映异构体分离检测的影响。优化后的色谱条件为:以Daicel CHIRALPAKAD-H手性色谱柱为分离柱,正己烷-乙醇-二乙胺(900∶100∶1)为流动相;检测波长为220 nm;流速为1 mL/min;柱温为30℃。该色谱条件专属性良好(分离度≥2.0);精密度良好(RSD≤2.0%);对映异构体、非对映异构体Ⅰ、非对映异构体Ⅱ分别在0.240 5~10.822 5,0.186 8~8.406 0,0.196 1~8.824 5μg/mL范围内线性关系良好(r≥0.999);检出限为0.062 25~0.080 13μg/mL,定量下限为0.186 8~0.240 5μg/mL;加标回收率为94.4%~95.7%,相对标准偏差为2.5%~3.1%。该方法简便、有效,可用于生产中琥珀酸索利那新原料药中对映异构体和非对映异构体的含量检测。     

Determination of Amoxycillin and Clavulanic Acid in Some Pharmaceutical Preparations by Derivative Spectrophotometry

 Derivative spectrophotometry was applied for the simultaneous determination of amoxycillin and clavulanic acid in pharmaceutical preparations: “Augmentin” inj. and tablets and “Amoksiklav” drops and tablets, in solutions after hydrolysis with sodium hydroxide. As the absorption spectra overlap strongly (amoxycillin λ_max = 247 nm and 290 nm, clavulanic acid λ_max = 258 nm) the first and the second derivative spectrophotometric procedure was elaborated for their determination. Amoxycillin was determined at λ = 257.9 nm (1-st derivative spectra) or λ = 273 nm (2-nd derivative) while clavulanic acid at λ = 280.3 nm (1-st derivative) or λ = 285 nm (2-nd derivative spectra). The Beer’s law is obeyed in the range of 0.004–0.04 mg/ml for amoxycillin and 0.002–0.02 mg/ml for clavulanic acid. Received December 6, 1999. Revision August 1, 2000.     

Determination of Oxazepam in Pharmaceutical Formulation by HPTLC UV-Densitometric and UV-Derivative Spectrophotometry Methods

Abstract

Methods for determination of oxazepam in pharmaceutical formulation by derivative ultraviolet (UV) spectrophotometry as well as high-performance thin-layer chromatography (HPTLC) UV densitometry were described. For UV-derivative spectrophotometry, some derivatives and wavelengths may be recommended for routine quality control of the drug of interest. On the other hand, HPTLC provided good results, but only when the calibration curve was estimated using nonlinear regression analysis. The HPTLC method was developed with silica F₂₅₄ plates, a mobile phase of benzene/ethanol (5:1, v/v), and densitometric detection at 204 nm receiving R _f  = 0.47. Developed methods were validated and found to be sufficiently precise and reproducible for established conditions.     

Determination of Piribedil in Human Serum, Urine and Pharmaceutical Dosage Form by LC-DAD

A rapid, selective and sensitive reversed-phase liquid chromatographic (LC) method was developed for the determination of piribedil in human serum, urine and pharmaceutical dosage form. LC analysis was carried out using reversed-phase isocratic elution with a C₁₈ column and a mobile phase of 0.01 M phosphate buffer-acetonitrile (50:50, v/v). The chromatograms showed good resolution and sensitivity with no interference of human serum and urine. Piribedil concentrations were determined using diode array detection at 240 nm. Sildenafil citrate was used as internal standard. The limit of quantification (LOQ) and limit of detection (LOD) concentrations were 107.2 and 321.6 pg mL^?1, 96.6 and 290.4 pg mL^?1, 161.7 and 53.9 pg mL^?1 for urine, serum and pharmaceutical dosage forms, respectively. The method was validated for its linearity, precision and accuracy and applied to the tablets, urine and human serum. In addition, the results were compared to those obtained from UV-spectrophotometry.     

Simultaneous Determination of Enalapril and Losartan in Pharmaceutical Preparations by UV Spectrophotometry and LC

The simultaneous determination of enalapril (Ena) and losartan (Los) in solid dosage forms were done by two methods. The first method involves spectrophotometric determination using the simultaneous equation method at 222 and 250 nm for Ena and Los, respectively. The second method involved an RP-LC method of analysis using methanol:water:acetonitrile (45:35:20% v/v) as the mobile phase. Both methods were satisfactorily validated as per ICH guidelines.