Performance characteristics of high performance liquid chromatography, first order derivative UV spectrophotometry and bioassay for fluconazole determination in capsules

The bioassay, first order derivative UV spectrophotometry and chromatographic methods for assaying fluconazole capsules were compared. They have shown great advantages over the earlier published methods. Using the first order derivative, the UV spectrophotometry method does not suffer interference of excipients. Validation parameters such as linearity, precision, accuracy, limit of detection and limit of quantitation were determined. All methods were linear and reliable within acceptable limits for antibiotic pharmaceutical preparations being accurate, precise and reproducible. The application of each method as a routine analysis should be investigated considering cost, simplicity, equipment, solvents, speed, and application to large or small workloads.

Performance characteristics of bioassay UV-spectrophotometry and high perfomance liquid chromatographic determination of gatifloxacin in tablets

The microbiological bioassay, UV-spectrophotometry and HPLC methods for assaying gatifloxacin in tablets were compared. Validation parameters such as linearity, precision, accuracy, limit of detection and limit of quantitation were determined. Beer's law was obeyed in the ranges 4.0-14.0 μg/mL for HPLC and UV-spectrophotometric method, and 4.0-16.0 μg/mL for bioassay. All methods were reliable within acceptable limits for antibiotic pharmaceutical preparations being accurate, precise and reproducible. The bioassay and HPLC are more specific than UV-spectrophotometric analysis. The application of each method as a routine analysis should be investigated considering cost, simplicity, equipment, solvents, speed, and application to large or small workloads.

Losartan potassium dissolution test for drug release evaluation in pharmaceutical capsules using HPLC and UV spectrophotometry

This work describes the development and validation of a dissolution test for 50 mg losartan potassium capsules using HPLC and UV spectrophotometry. A 2(4) full factorial design was carried out to optimize dissolution conditions and potassium phosphate buffer, pH 6.8 as dissolution medium, basket as apparatus at the stirring speed of 50 rpm and time of 30 min were considered adequate. Both dissolution procedure and analytical methods were validated and a statistical analysis showed that there are no significant differences between HPLC and spectrophotometry. Since there is no official monograph, this dissolution test could be applied for quality control routine.

UV derivative spectrophotometric method for determination of estradiol valerate in tablets

A derivative UV spectrophotometric method for determination of estradiol valerate in tablets was validated. The parameters specificity, linearity, precision, accuracy, limit of detection and limit of quantitation were studied according to validation guidelines. The first-order derivative spectra were obtained at N = 5, Δλ = 4.0 nm, and determinations were made at 270 nm. The method showed specificity and linearity in the concentration range of 0.20 to 0.40 mg mL-1. The intra and interday precision data demonstrated the method has good reproducibility. Accuracy was also evaluated and results were satisfactory. The proposed method was successfully applied to a pharmaceutical formulation.

Derivative spectrophotometric method for determination of acyclovir in polymeric nanoparticles

A derivative spectrophotometric method was validated for quantification of acyclovir in poly (n-butylcyanoacrylate) (PBCA) nanoparticles. Specificity, linearity, precision, accuracy, recovery, detection (LOD) and quantification (LOQ) limits were established for method validation. First-derivative at 295.2 nm eliminated interferences from nanoparticle ingredients and presented linearity for acyclovir concentrations ranging from 1.25 to 40.0 µg/mL (r = 0.9999). Precision and accuracy data demonstrated good reproducibility. Recovery ranged from 99.3 to 101.2. LOD was 0.08 µg/mL and LOQ, 0.25 µg/mL. Thus, the proposed method proved to be easy, low cost, and accurate, and therefore, an useful alternative to quantify acyclovir in nanoparticles.

Espectrofotometria derivativa: uma estratégia simples para a determinação simultânea de corantes em alimentos

A very simple spectrophotometric method is described for resolving binary mixture of the food colorants Sunset Yellow (INS 110) and Tartrazine Yellow (INS 102) by using the first derivative spectra with measurements at zero-crossing wavelengths. Before the spectrophotometric measurements, the dyes were sorbed onto polyurethane foam and recovered in N,N-dimethilformamide. Commercial food products (gelatine and juice powder) were analysed by using the proposed method and the HPLC technique. The results are in very good agreement and the differences between the methods is not statistically important. Therefore, the first-order derivative spectrophotometric method is accurate, precise, reliable and could be applied to the routine analysis of food samples.

Dissolution test for glibenclamide tablets

The aim of this work is to develop and validate a dissolution test for glibenclamide tablets. Optimal conditions to carry out the dissolution test are 500 mL of phosphate buffer at pH 8.0, paddles at 75 rpm stirring speed, time test set to 60 min and using equipment with six vessels. The derivative UV spectrophotometric method for determination of glibenclamide released was developed, validated and compared with the HPLC method. The UVDS method presents linearity (r² = 0.9999) in the concentration range of 5-14 µg/mL. Precision and recoveries were 0.42% and 100.25%, respectively. The method was applied to three products commercially available on the Brazilian market.

Validation of a simple and rapid UV spectrophotometric method for dexamethasone assay in tablets

This work reports the validation of an analytical UV spectrophotometric method to assay dexamethasone in tablets (assay and dissolution studies). The method was linear in the range between 1 and 30 µg mL-1 presenting a good correlation coefficient (r = 0.9998, n = 7). Precision and accuracy analysis showed low relative standard deviation (< 2.00%) and good percentual recoveries (95-105%). The procedure was linear, accurate, precise, and robust. The method is simple, and it has low cost. It does not use polluting reagents and can be applied in dissolution studies, being an adequate alternative to assay dexamethasone in tablets.

Determinação de olanzapina em formulações farmacêuticas por espectrofotometria: desenvolvimento e validação

Spectrophotometric methods of zero order, first and second derived order had been developed for olanzapine determination in tablets using ethanol and isopropanol as solvent. The two solvents revealed to be adequate. For the three methods the calibration curve coefficient of correlation had been greater than 0.9998 with limit of detection varying from 0.068 to 0.190 mg L-1, in ethanol, and 0.026 to 0.205 mg L-1, in isopropanol. The inter-day precision was inferior to 1.1 and 1.9 mg L-1 for ethanol and isopropanol, respectively. The average recoveries varied from 98 to 101%, in ethanol and 99 to 103% in isopropanol.

Desenvolvimento e validação de um método analítico simples e rápido por espectroscopia UV para quantificação de aciclovir em matrizes hidrofílicas de liberação prolongada

This work reports the validation of an analytical UV spectrophotometric method to assay acyclovir in hydrophilic matrices (assay and dissolution studies). The method was linear in the range between 2.5-20 µg mL-1, presenting a good correlation coefficient ( r = 0,9999). Precision and accuracy analysis showed low relative standart deviation (< 2.0 %) and a good recoveries percentual (98.9-100 %). The procedure was linear, accurate, and robust. The method is simple and cheap. It does not use polluting reagents and can be applied in dissolution studies, being an adequate alternative to assay acyclovir in hydrophilic matrices tablets.

Development and validation of UV spectrophotometric method for determination of levofloxacin in pharmaceutical dosage forms

The objective of this research was to develop and validate an alternative analytical method for quantitative determination of levofloxacin in tablets and injection preparations. The calibration curves were linear over a concentration range from 3.0 to 8.0 μg mL-1. The relative standard deviation was below 1.0% for both formulations and average recovery was 101.42 ± 0.45% and 100.34 ± 0.85% for tablets and injection formulations, respectively. The limit of detection and limit of quantitation were 0.08 and 0.25 μg mL-1, respectively. It was concluded that the developed method is suitable for the quality control of levofloxacin in pharmaceuticals formulations.

Development and validation of an UV spectrophotometric method for the determination of aliskiren in tablets

For determination of aliskiren in commercial samples, an analytical UV spectrophotometric method was developed and validate according to ICH guideline. The method was linear in the range between 40 and 100 μg mL-1 (r² = 0.9997, n = 7) and exhibited suitable specificity, accuracy, precision, and robustness. It is simple, it has low cost, and it has low use polluting reagents. Therefore, the proposed method was successfully applied for the assay and dissolution studies of aliskiren in tablet dosage forms, and the results were compared to a validated RP-LC method, showing non-significant difference (P > 0.05).

Validação de método espectrofotométrico na região do UV para quantificação de famotidina em cápsulas

This work describes the validation of a method for quantification of famotidine in capsules by UV spectrophotometry using as solvents buffer solution at pH 2.5 and buffer solution at pH 4.5. The results show that the method is practical, selective, accurate, precise and linear from 10.0 to 25.0 µg/mL of famotidine in both solvents. However, a variance analysis showed a lower mean percentage of famotidine when buffer at pH 2.5 is used. This effect was attributed to the instability of famotidine in acidic media. Therefore, the use of pH 4.5 buffer was considered suitable for analysis of famotidine in capsules.

Simultaneous spectrophotometric determination of lamivudine and zidovudine in fixed dose combinations using multivariate calibration

The simultaneous determination of two or more active components in pharmaceutical preparations, without previous chemical separation, is a common analytical problem. Published works describe the determination of AZT and 3TC separately, as raw material or in different pharmaceutical preparations. In this work, a method using UV spectroscopy and multivariate calibration is described for the simultaneous measurement of 3TC and AZT in fixed dose combinations. The methodology was validated and applied to determine the AZT+3TC contents in tablets from five different manufacturers, as well as their dissolution profile. The results obtained employing the proposed methodology was similar to methods using first derivative technique and HPLC.

Desenvolvimento e validação de um método analítico por espectrofotometria UV para quantificação de carvedilol

This paper reports the development and validation of a new analytical method using UV spectrophotometry to quantify carvedilol (CRV) in hydrophilic matrices and raw material. This method was shown to be linear, accurate, precise, robust and to have adequate limits of quantification and detection (LQ and LD, respectively), allowing its use in the dissolution test of hydrophilic matrices. The content of CRV determined through this method was compared with two previously validated methods based on the reference techniques of High Performance Liquid Chromatography (HPLC) and Potentiometric Titrations (PT). ANOVA confirmed the equivalence of these methods, showing no significant differences.