Determination Of Gemfibrozil Research Articles

Determination of Gemfibrozil in Drug Matrix and Human Biological Fluid by Dispersive Liquid-Liquid Microextraction with High Performance Liquid Chromatography

A simple and rapid dispersive liquid-liquid microextraction technique coupled with high performance liquid chromatography (HPLC) was developed for the extraction and analysis of gemfibrozil in drug matrix and biological fluids like human plasma and urine samples. In this method, carbon tetrachloride at microliter volume level and methanol were used as extraction and disperser solvents, respectively. The effects of factors including the type and volume of disperser and extraction solvents, pH and extraction time on the performance of the sample preparation were carefully evaluated. Under optimum conditions, the obtained enrichment factors were between 9.2 - 9.3 and extraction recoveries were high and ranged between 91.2 - 93.2%. The calibration curve was linear in the range of 0.1 - 100 mg/L with a detection limit of 12.3 µg/L. The relative standard deviation (RSD) for ten replicate measurements of gemfibrozil was 1.3%. The performance of the method was checked by the analysis of the gemfibrozil in presence of other drugs in water samples.

Determination of Gemfibrozil (Lipitor and Lopid) in Water, Biological Fluids and Drug Matrix by Dispersive Liquid-Liquid micro Extraction (DLLME) and Liquid Chromatography

In this study Dispersive liquid-liquid micro extraction (DLLME) coupled with High performance liquid chromatography was applied for the determination of Gemfibrozil in water, drug`s matrix and biological liquids (human plasma and urine). In this method, the appropriate mixture of extraction solvent (200 μl chlorophorm) and disperser solvent (1 ml methanol) are injected rapidly into the aqueous sample (10.0 ml) by syringe, cloudy solution is formed that consisted of fine particles of extraction solvent which is dispersed entirely into aqueous phase. The mixture was centrifuged and the extraction solvent is sedimented on the bottom of the conical test tube. 50 μl of the sedimented phase is puted in a vial and it`s solvent is evaporated. Then 1ml methanol injected to vial and 20 μL of it injected into the HPLC for separation and determination of Gemfibrozil. Some important parameters, such as kind of extraction and disperser solvent, volume of them, extraction time, pH and ionic strength of the aqueous feed solution were optimized. Under the optimum conditions, the enrichment factors and extraction recoveries were 10 and 93.64%. The linear range was (0.1-100.0 mgl-1 ), limit of detection was 12.3 mgl-1 . The relative standard deviations (RSD) for 2 mgl-1 of Gemfibrozil in water were 1.3%, (n=10).

CYCLIC VOLTAMMETRIC STUDIES OF GEMFIBROZIL AT POLY (GABAPENTIN) FILM MODIFIED GLASSY CARBON ELECTRODE

A polymerized film of gabapentin was prepared on the surface of a glassy carbon electrode (GCE) in phosphate buffer solution by electropolymerisation method using cyclic voltammetric technique. The poly (gabapentin) film modified glassy carbon electrode was calibrated with standard potassium ferrocyanide solution in 1 M KCl as a supporting electrolyte. This modified electrode used to study the electrochemical behavior of gemfibrozil, a lipid lowering drug in aqueous alcohol medium by cyclic voltammetric technique. It was found that the oxidation peak current of gemfibrozil at the modified GCE was greatly improved compared with that at the bare GCE. The effects of scan rate, pH, supporting electrolyte concentration, % of solvent and concentration of gemfibrozil were examined. With high sensitivity and selectivity, micro molar detection limit, high reproducibility together with ease of preparation and regeneration of the electrode surface make the electrode very stable for the determination of gemfibrozil in pharmaceutical and clinical preparations.

LC Determination and Pharmacokinetic Study of Gemfibrozil in Human Plasma

A simple and sensitive LC method for the quantitative determination of gemfibrozil in human plasma samples is described. Mometasone furoate was used as the internal standard. Plasma samples were pretreated by protein precipitation using methanol. Separation was performed at 40 °C on a YMC® ODS-A reverse phase column (5 μm particle size, 150 mm × 4.6 mm i.d.) using 0.2% (v/v) triethylamine in water (adjusting to pH 4.0 with phosphoric acid) and acetonitrile (45:55, v/v) as mobile phase which was delivered at 1.5 mL min−1. Ultraviolet detection was performed at 230 nm. The linear concentration range for gemfibrozil was 0.25–50 μg mL−1. The detection limit of this method was 0.1 μg mL−1. Intra- and inter-assay RSD ranged from 0.63 to 2.04% and 1.37 to 4.27%, respectively. The method was sensitive, simple and repeatable enough to be used in pharmacokinetic studies.

Development of a new analytical spectroscopic methodology based on the competitive aggregation in a dye–surfactant–drug system: Application to the determination of gemfibrozil

A new analytical methodology based on the competitive aggregation in a dye–surfactant–drug system is developed for the determination of gemfibrozil. Eriochrome Blue Black R (EBBR) and Didodecyldimethylammonium bromide (DDABr) were the dye and surfactant used, respectively. In the proposed method, the anions of the dye bind to the cationic surfactant molecules to form dye–surfactant aggregates, which are monitored from changes in UV-Vis absorption features of the dye. In the ternary EBBR–DDABr–drug mixtures, the drug competes with the dye to interact with the surfactant, which results in a decrease in dye–surfactant aggregates formation. This, again, causes a change in absorption properties of the dye. The measurement parameter is the difference between the absorption of the dye in the presence and absence of the drug. In the appropriate experimental conditions the absorbance differences are directly proportional to the drug concentration. The influence of several experimental variables such as pH, concentrations of buffer, EBBR and DDABr on the measurement parameter were studied. Under the optimum conditions, the calibration graph was linear up to 6.0 μg ml−1with the correlation coefficient of 0.998. The limit of detection and quantification were found to be 0.044 and 0.15 μg ml−1, respectively. The method was validated and applied to the determination of gemfibrozil in pharmaceutical preparations.

Simple and Sensitive HPLC Method for Determination of Gemfibrozil in Human Plasma with Fluorescence Detection

A sensitive and simple high performance liquid chromatography (HPLC) with fluorescence detection was developed for the determination of gemfibrozil in a small plasma sample. The plasma sample was analyzed by a deproteination method that had very simple pretreatment steps. Ibuprofen was used as an internal standard. The analysis of gemfibrozil in the plasma sample was carried out using a reverse phase C18 column with fluorescence detection (a maximum excitation at 242 nm and a minimum emission at 300 nm). A mixture of acetonitrile–0.4% phosphoric acid solution (53∶47, v/v) was used as a mobile phase. The detection limit of this method was 10 ng/mL using only 100 µL of plasma sample. The standard curve was an excellent linear fit over a range of 0.05–15 µg/mL of gemfibrozil in human plasma (r2=1). The inter‐ and intra‐day precision (coefficient of variation, CV%) did not exceed 15%. This simple, sensitive, and rapid method was successfully applied for the pharmacokinetic study following a single oral administration of 300 mg gemfibrozil.

Validated Flow Injection Spectrophotometric Assay for the Quality and Stability Control of Gemfibrozil Tablets

A validated flow injection spectrophotometric assay has been developed and optimized for the determination of gemfibrozil in pharmaceutical formulations. The method is based on the direct measurement of the absorbance of the analyte—under flow conditions—in basic medium, at 276 nm. The assay was optimized in terms of sample injection volume and flow rate and validated in terms of linearity, repeatability, detection limit, accuracy, and selectivity. Linear calibration curve was obtained in the range of 20–100 mg l−1, while the detection limit (1.4 mg l−1), the repeatability (s r <1.0%, n=12) and the sampling rate (30 h−1) were satisfactory. The method was applied successfully to the quality control of one batch (batch no. 052) and the stability control of three batches (batches no. 049–051) of a gemfibrozil‐containing formulation (Prelisin®, Cosmopharm Ltd, Greece).

Determination of gemfibrozil by HPLC in pharmacokinetic studies

Determination of gemfibrozil by HPLC in pharmacokinetic studies