ABSTRACT
A Simple, rapid, specific, accurate, economical and precise UV spectrophotometric and RP-HPLC methods (inaccordance with ICH guidelines) were developed and validated for determination of Nortriptyline hydrochlorideand Pregabalin in tablet dosage form. The first method was based on Q - absorbance ratio, and absorbances ofboth drugs were determined at 239 nm (λmax of Nortriptyline Hydrochloride) and 235 nm (Iso-absorptive Point)when dissolved in methanol. It is found that Pregabalin does not have chromophoric group. To be UV-sensitive,it was compulsory to introduce chromophoric group in Pregabalin structure and make it UV-sensitive. This wasachieved by converting the primary amine group of Pregabalin through reaction with benzoyl chloride to formbenzoylated derivative of Pregabalin. Benzoylated Pregabalin was determined at 225 nm using UV-visiblespectrophotometer. The second method was based on RP-HPLC. The chromatographic separation was performedon an Inertsil ODS C18 column (250 x 4.6mmx 5 μm) with a mobile phase of 0.56 %w/v Sodium hexane sulphonicacid dissolved in water acetonitrile (50:50 %v/v, pH 4.5 adjusted with Glacial Acetic Acid) at flow rate of 1.0mL/min with DAD detection wavelength at 210 nm. Retention times of Nortriptyline Hydrochloride andPregabalin were 7.3894 min and 4.0506 min, respectively. Beer-Lambert’s law obeyed the concentration rangeof 2-12 μg/mL for Nortriptyline Hydrochloride and 10-60 μg/mL for Pregabalin. The results indicated that bothspectrophotometric and RP-HPLC methods were linear, accurate, precise and robust with RSD values less than0.2% and % recovery was within the standard limits (99 - 102%).
ABSTRACT
Three new UV spectrophotometric methods namely simultaneous equation, absorbance ratio and first derivative (zero crossing) spectroscopic methods were developed and validated for simultaneous estimation of teneligliptin hydrobromide hydrate and metformin hydrochloride in tablet formulation which were simple, sensitive, precise and accurate. In simultaneous equation method, absorbance was measured at 237 and 246 nm for both the drugs. Teneligliptin hydrobromide hydrate and metformin hydrochloride was estimated using 237 and 247.5 nm in absorbance ratio method. First derivative (zero crossing) method was based on the transformation of UV spectra in to first derivative spectra followed by measurement of first derivative signal at 237 and 246 nm for teneligliptin hydrobromide hydrate and metformin hydrochloride, respectively using 2 nm as wavelength interval (Δλ) and 1 as scaling factor. Developed methods were validated according to ICH guidelines including parameters viz., specificity, linearity and range, precision, accuracy, limit of detection and quantification. All the three methods showed linear response in the concentration range of 1-20 µg/ml for both the drugs. Results of method validation parameters follows ICH guideline acceptable limits. Based on the assay results obtained, methods were compared using one-way ANOVA followed by Bonferroni multiple comparison tests (95% confidence level) using computer based fitting program (Prism, Graphpad version 5, Graphpad Software Inc). Outcome of the statistical analysis proved that there was no considerable dissimilarity between all the developed methods. Methods were found to be simple, fast, highly sensitive, cost effective and hence can be useful for simultaneous estimation of teneligliptin hydrobromide hydrate and metformin hydrochloride in commercial tablet formulation for routine quality control analysis.
ABSTRACT
Three simple, sensitive, precise and accurate UV-spectroscopic methods namely simultaneous equation, absorbance ratio and first derivative (zero crossing) spectroscopic methods were developed and validated for simultaneous determination of aliskiren hemifumarate and hydrochlorothiazide in tablet dosage form. Simultaneous equation method was based on the measurement of absorbance at 271 and 280 nm for both the drugs. In absorbance ratio method 255 and 271 nm was used for the quantification of aliskiren hemifumarate and hydrochlorothiazide. First derivative method was involved in the conversion of UV-spectra in to first derivative spectra and measurement of first derivative signal at 241 and 280.2 nm for aliskiren hemifumarate and hydrochlorothiazide, respectively using 2 nm as wavelength interval (Δλ) and 1 as scaling factor. Methods were validated as per ICH guidelines including parameters viz., specificity, linearity and range, precision, accuracy, limit of detection and quantification. All the methods were found to be linear in the concentration range of 6-300 μg/ml for aliskiren hemifumarate and 0.5-25 μg/ml for hydrochlorothiazide. Results of validation studies follows ICH guideline acceptable limits. Methods were compared based on the assay results obtained using one-way ANOVA followed by Bonferroni multiple comparison tests (95% confidence level) as appropriate using computer based fitting program (Prism, Graphpad version 5, Graphpad Software Inc). Results of statistical analysis revealed that there was no significant difference between simultaneous equation, absorbance ratio and first derivative method. Developed methods were simple, rapid, highly sensitive and cost effective as compared to existing methods and can be useful for simultaneous estimation of aliskiren hemifumarate and hydrochlorothiazide in commercial tablet formulation for routine quality control.
ABSTRACT
The present manuscript describe simple, sensitive, rapid, accurate, precise and economical Q-absorbance ratio method for the simultaneous determination of Rifampicin and Piperine in combined capsule dosage form. Absorbance ratio method uses the ratio of absorbances at two selected wavelengths, one which is an isoabsorptive point and other being the λ-max of one of the two components. Rifampicin and Piperine show an isoabsorptive point at 387 nm in methanol. The second wavelength used is 337 nm, which is the λ-max of Piperine in methanol. The linearity was obtained in the concentration range of 5-40 μg/ml for Rifampicin and 2-20 μg/ml for Piperine. The concentrations of the drugs were determined by using ratio of absorbances at isoabsorptive point and at the λ-max of Rifampicin. The method was successfully applied to pharmaceutical dosage form because no interference from the capsule excipients was found. The results of analysis have been validated statistically and by recovery studies.
ABSTRACT
The present manuscript describe simple, sensitive, rapid, accurate, precise and economical Q-absorbance ratio method for the simultaneous determination of cefpodoxime proxetil and ofloxacin in combined tablet dosage form. Absorbance ratio method uses the ratio of absorbances at two selected wavelengths, one which is an isoabsorptive point and other being the λ-max of one of the two components. Cefpodoxime proxetil and ofloxacin show an isoabsorptive point at 273.2 nm in methanol. The second wavelength used is 297 nm, which is the λ-max of ofloxacin in methanol. The linearity was obtained in the concentration range of 2-14 μg/ml for both cefpodoxime proxetil and ofloxacin. The concentrations of the drugs were determined by using ratio of absorbances at isoabsorptive point and at the λ-max of ofloxacin. The method was successfully applied to pharmaceutical dosage form because no interference from the tablet excipients was found. The results of analysis have been validated statistically and by recovery studies.