Development and validation of a GC-FID assay for determination of fluvastatin in pharmaceutical preparations

A gas chromatographic method has been developed for the assay of fluvastatin sodium (FLU). FLU was silylated with N,O-bis(trimethylsilyl)trifluoroacetamide-1% trimethylchlorosilane at 90 ºC for 30 min and analysed in a DB-1 column by capillary gas chromatograph with a flame ionization detector. The method was validated. The assay was linear over the concentration range at 10.0 to 50.0 µg mL-1. The limit of detection and the limit of quantitation were 1.0 and 3.0 µg mL-1, respectively. The recoveries of FLU derivatives were in the range of 99.25-99.80%. In inter-day and intra-day analysis, the values of relative standard deviation (%) and the relative mean error (%) were found between 0.20-0.80% and -0.20-0.75%, respectively. The developed method was succesfully applied to analyze the FLU content in tablet formulation. The results were statistically compared with those obtained by the official method, and no significant difference was found between the two methods. Therefore, it can be recommended for the quality control assay of FLU in pharmaceutical industry

Spectro photo metric and spectrofluorimetric methods for the determination of pregabalin in bulk and pharmaceutical preparation

Two new, sensitive and selective spectrofluorimetric and spectrophotometric methods have been developed for the determination of the gamma-amino-n-butyric acid derivative pregabalin (PGB) in bulk drug and capsule. Pregabalin, as a primary amine compound, reacts with 7-chloro-4-nitrobenzofurazon (NBD-Cl) which is a highly sensitive fluorogenic and chromogenic reagent used in many investigations. According to this fact, spectrophotometric and spectrofluorimetric methods for the determination of pregabalin in capsules were developed for the first time. The relation between the absorbance at 460 nm and the concentration is rectilinear over the range 0.5-7.0 mu g mL(-1). The reaction product was also measured spectrofluorimetrically at 558 nm afterexcitation at 460 nm. The fluorescence intensity was directly proportional to the concentration over the range 40-400 ng mL(-1). The method was applied successfully to the determination of this drug in pharmaceutical dosage form. The mean recovery for the commercial capsules was 99.93% and 99.96% for spectrophotometric and spectrofluorimetric study, respectively. The suggested procedures could be used for the determination of PGB in pure and capsules being sensitive, simple and selective. (C) 2008 Elsevier B.V. All rights reserved

Determination of Gemifloxacin in Human Serum by Online Heart-Cutting Liquid Chromatography: Application to Pharmacokinetic Study

Introduction: In this assay, a new selective online heart-cutting Liquid Chromatographic method was developed for the quantification of gemifloxacin in serum samples

Determination of Ciprofloxacin in Human Serum by Online Heart-Cutting Liquid Chromatography

In this study, a very simple, selective and sensitive new online heart-cutting liquid chromatographic method was developed for the determination of ciprofloxacin in human serum. The proposed method allows the determination of ciprofloxacin in human serum without complex sample preparation. The samples were mixed with methanol and filtered before analysis. Separations were performed with the following systems: the first dimension consisted of a biphenyl (50 mm x 2.1 mm) pre-separation column and the mobile phase of 25 % methanol: 75 % 30 mM ortho-phosphoric acid solution mixture, and the second dimension consisted of a C18 (150 mm x 4.6 mm) separating column and the mobile phase of 15 % acetonitrile: 85 % 50 mM ortho-phosphoric acid (pH 3.5, 100 mM triethylamine) solution mixture. The two systems were connected with a six-port valve including a 200-mu L sample loop and separations were performed continuously through injections. Detection wavelength was selected as 279 nm for both systems. The calibration curve was linear over a concentration range of 0.05-5 mu g mL(-1). The accuracy and precision of the method were determined to be 1.32-4.00 and 1.70-4.27 % ranges for RSD and RME, respectively. The absolute recovery of the drug was found to be 94.97 %. The developed method was successfully applied for the determination of ciprofloxacin in serum samples collected from a volunteer who had received 500 mg ciprofloxacin orally

DEVELOPMENT AND VALIDATION OF A GC-FID ASSAY FOR DETERMINATION OF FLUVASTATIN IN PHARMACEUTICAL PREPARATIONS

A gas chromatographic method has been developed for the assay of fluvastatin sodium (FLU). FLU was silylated with N,O-bis(trimethylsilyl)trifluoroacetamide-1% trimethylchlorosilane at 90 degrees C for 30 min and analysed in a DB-1 column by capillary gas chromatograph with a flame ionization detector. The method was validated. The assay was linear over the concentration range at 10.0 to 50.0 mu g mL(-1). The limit of detection and the limit of quantitation were 1.0 and 3.0 mu g mL(-1), respectively. The recoveries of FLU derivatives were in the range of 99.25-99.80%. In inter-day and intra-day analysis, the values of relative standard deviation (%) and the relative mean error (%) were found between 0.20-0.80% and -0.20-0.75%, respectively. The developed method was succesfully applied to analyze the FLU content in tablet formulation. The results were statistically compared with those obtained by the official method, and no significant difference was found between the two methods. Therefore, it can be recommended for the quality control assay of FLU in pharmaceutical industry

A very simple high-performance liquid chromatographic method with fluorescence detection for the determination of gemifloxacin in human breast milk

A high-performance liquid chromatographic method with fluorescence detection was developed and validated for the determination of gemifloxacin in human breast milk. The proposed method allows the determination of gemifloxacin in breast milk samples without complex sample preparation. The samples were mixed with a mobile phase and filtered with a 0.45 mu m polytetrafluoroethylene filter before analysis. Chromatographic separation was carried out on a C18 column (150 x 4.6mm, 5 mu m I.D.) usingmethanol:50 mM ortho-phosphoric acid solution (40:60) as the mobile phasewith a 1.0 mL/min flow rate. Quantitation was performed using fluorescence detection with an excitation wavelength at 272 nm and an emission wavelength at 395 nm. The linear range was found to be 0.1-2.5 mu g/mL. The method was applied successfully for the determination of gemifloxacin in breast milk obtained from a breastfeeding mother after oral administration of a single tablet that included 320 mg gemifloxacin per gemifloxacin tablet. Copyright (C) 2015 John Wiley & Sons, Ltd

Online Heart-Cutting Liquid Chromatographic Analysis of Linezolid in Human Serum

In this assay, a selective, simplistic and sensitive new online heart-cutting Liquid Chromatographic analysis method was developed for the quantification of linezolid in human serum. The new method allows to the quantification of linezolid in serum without complicated sample preparation. Before analysis, the samples were mixed with methanol and filtered. Separations were carried out with following systems; 1st dimension is a system consisting of 2.1 x 50 mm Biphenyl pre-separation column with acetonitrile and 0.03 M o-phosphoric acid solution mixture (15: 85) as mobile phase and the 2nd dimension is a system consisting of 4.6 x 150 mm Pentafluorophenyl propyl separating column with acetonitrile and 0.03 M o-phosphoric acid solution mixture (25:75) as mobile phase. Two systems were connected via a 6-port valve having 0.2 mL loop and separations were carried out continuously during injections. For both systems, 250 nm has been selected as detection wavelength. The concentration range of 0.5-20 mu g/mL was found as linear calibration curve. The new method was successfully applied for the quantification of linezolid in human serum samples collected from a volunteer who has received 600 mg linezolid orally

Determination of levofloxacin by HPLC with fluorescence detection in human breast milk

Aim: A new HPLC method with fluorescence detection has been developed and validated for the determination of levofloxacin, one of the fluoroquinolone class antibiotics, in breast milk. Materials & methods: Chromatographic separation was carried out on a reversed phase C18 column with acetonitrile and 10 mM o-phosphoric acid (25:75,v/v) mobile phase composition. Moxifloxacin was used as internal standard and the peaks were detected by fluorescence detection. Results & conclusion: Calibration graph was found linearly within the range of 2.5-500 ng/ml. Limit of detection and limit of quantification were found to be 0.63 and 2.11 ng/ml, respectively. Mean absolute recovery was 96.18%. The developed method has been successfully applied to the determination of levofloxacin in human breast milk taken from two healthy volunteers

LC assay of eletriptan in tablets and in vitro dissolution studies

Eletriptan (ELT) is a new selective serotonin agonist approved for the treatment of acute migraine headaches. A simple and rapid liquid chromatographic method was developed and validated for the assay of ELT in tablets. Chromatography was carried out on a 250 mm x 4.6 mm C(18) column at 30 C. Acetonitrile-15 mM triethylamine solution (adjusted to pH 7.0 using concentrated o-phosphoric acid) (60:40, v/v) mixture was used as mobile phase at 1.0 mL min(-1) flow rate and UV detector was set at 225 nm. A linear response (r(2) = 0.9999) was observed in the range of 0.1-1.6 mu g mL(-1). The method showed good recoveries (100.08 %) and the RSD values for intra- and inter-day precision were 0.78-1.93 and 1.10-2.15%, respectively. The method can be used for quality control assays and in vitro dissolution studies of ELT in tablets

Development of sensitive spectrofluorimetric and spectrophotometric methods for the determination of duloxetine in capsule and spiked human plasma

A new, sensitive and selective spectrofluorimetric method has been developed for the determination of duloxetine (DLX) in capsule and spiked human plasma. DLX, as a secondary amine compound, reacts with 7-chloro-4-nitrobenzofurazon (NBD-Cl), a highly sensitive fluorogenic and chromogenic reagent used in many investigations. The method is based on the reaction between the drug and NBD-Cl in borate buffer at pH8.5 to yield a highly fluorescent derivative that is measured at 523nm after excitation at 478nm. The fluorescence intensity was directly proportional to the concentration over the range 50-250ng/mL. The reaction product was also measured spectrophotometrically. The relation between the absorbance at 478nm and the concentration is rectilinear over the range 1.0-12.0 mu g/mL. The methods were successfully applied for the determination of this drug in pharmaceutical dosage form. The spectrofluorimetric method was also successfully applied to the determination of duloxetine in spiked human plasma. The suggested procedures could be used for the determination of DLX in pure form, capsules and human plasma being sensitive, simple and selective. Copyright (c) 2014 John Wiley & Sons, Ltd