A simple, accurate and precise spectrophotometric method has been proposed for the determination of Mefenamic acid(MA) in dosage forms. Proposed  method based on the reaction of cited drug with 1,2-Naphthoquinone-4-Sulfonic sodium (NQS). The optimum experimental condition have been studied. Beer's Law is obeyed in the concentration range 0.5-10.0 µg/mL at 450nm with detection limit of 0.189µg/mL.  Effect of pH, reaction time, and volume of NQS on the determination of Mefenamic acid, have been examined. The proposed method has been successfully applied for the determination of  Mefenamic acid in pharmaceutical preparations.
 

A simple, economical and selective method employing ion pair dispersive liquid−liquid microextraction (DLLME) coupled with spectrophotometric determination of carbamazepine (CBZ) in pharmaceutical preparations and biological samples was developed. The method is based on reduction of Mo(VI) to Mo(V) using a combination of ammonium thiocyanate and ascorbic acid in acidic medium to form a red binary Mo(V) thiocyanate complex. After addition of CBZ to the complex, extraction of the formed CBZ−Mo(V)−(SCN)6 was performed using a mixture of methylene chloride and methanol. Then, the measurement of target complex was performed at the wavelength of 470 nm. The important extraction parameters affecting the efficiency of DLLME were studied and o

A simple, rapid and environmentally friendly dispersive liquid–liquid microextraction method-based spectrophotometric method for the trace determination of folic acid has been developed. The proposed method is based on the formation of a deep yellow product via reaction of folic acid and 1,2-naphthoquine-4-sulfonate at pH = 9. The formed complex was extracted using a mixture of chloroform and ethanol. Then, the tiny organic droplets were measured at λ = 520 nm. At the optimum conditions, linearity was ranged from 0.05 to 1.5 μg/mL for the standard and samples, with a linear correlation coefficient of 0.9996. The detection limits were 0.02, 0.027, 0.03, 0.02 and 0.04 μg/mL for standard, tablet (5 mg), tablet (1 mg), syrup and fl

The current work is characterized by simplicity, accuracy and high sensitivity Dispersive liquid - Liquid Micro Extraction (DLLME). The method was developed to determine Telmesartan (TEL) and Irbesartan (IRB) in the standard and pharmaceutical composition. Telmesartan and Irbesartan are separated prior to treatment with Eriochrom black T as a reagent and formation ion pair reaction dye. The analytical results of DLLME method for linearity range (0.2- 6.0) mg /L for both drugs, molar absorptivity were (1.67 × 105-    5.6 × 105) L/ mole. cm, limit of detection were (0.0242and0.0238), Limit of quantification were (0.0821and0.0711), the Distribution coefficient were

A simple and novel method was developed by combination of dispersive liquid-liquid microextraction with UV spectrophotometry for the preconcentartion and determination of trace amount of malathion. The presented method is based on using a small volume of ethylenechloride as the extraction solvent was dissolved in ethanol as the dispersive solvent, then the binary solution was rapidly injected by a syringe into the water sample containing malathion. The important parameters, such the type and volume of extraction solvent and disperser solvent, the effect of extraction time and rate, the effect of salt addition and reaction conditions were studied. At the optimum conditions, the calibration graph was linear in the range of 2-100 ng mL-1 of ma

Mefenamic acid belongs to non-steroidal anti-inflammatory drugs that are used widely for the treatment of analgesia. Our aim from this study is to establish a new assay for the quantitative determination of mefenamic acid (MFA) in the pharmaceutical sample by two sensitive and rapid flow injection-fluorometric methods. A homemade fluorometer was used in fluorescence measurements, which using solid-state laser diode 405 and 532 nm as a source, combined with a continuous flow injection technique. The first method depends on the effect of MFA on calcein blue (CLB) fluorescence at 405 nm. Another method is a study of rhodamine-6G (Rh-6G) fluorescence after adding MFA, and recording at 532 nm. Optimum parameters as fluorescent dye concen

Determination of vitamin B₆ (pyridoxine hydrochloride) was described using high performance liquid chromatographic method. The analysis was achieved by cosmos IL 5C₁₈-MS-II column (250 mm x 4.6 mm i. d., 5µm particle size) at room temperature. The mobile phase used was Acetonitrile, buffer solution (Citric acid, Na₂HPO₄ pH4) buffer solution in the ratio (70:30) (V: V). the flow rate was set to 1.25 mL.min^-1 and the retention time 1.82 min with UV-detection at 282 nm. Beer's law was obeyed over the concentration range 10-1250 µg.mL^-1. The method was accurate (relative error % less than 0.05%), precise (RSD better than ±1.05%), average recovery 100.

Amiodarone hydrochloride (AH) has been determined spectrophotometrically Using methyl orange (MO).  In our previous researches MO was used for determination of Mexiletine Hydrochloride [1]. The method based on complexation between MO and AH.  After shaking and diluting the complex solution with D.W, the pH was adjusted with NaOH and HCl to pH 3. The colored complex formed between AH and the reagent were transferred into separating funnels and extracted using 5.5ml CH2Cl2 and were shaken for (5 minutes).  The extracted organic layer was used for preparation of the calibration curves for spectrophotometric measurements of AH at 434nm.  The blanks were carried out in exactly the same way throughout the whole procedure.&n

A new, Simple, sensitive and accurate spectrophotometric methods have been developed for the determination of sulfamethoxazole (SMZ) drug in pure and dosage forms. This method based on the reaction of sulfamethoxazole (SMZ) with 1,2-napthoquinone-4-sulphonic acid (NQS) to form Nalkylamono naphthoquinone by replacement of the sulphonate group of the naphthoquinone sulphonic acid by an amino group. The colored chromogen shows absorption maximum at 460 nm. The optimum conditions of condensation reaction forms were investigated by (1) univariable method, by optimizing the effect of experimental variables (different bases, reagent concentration, borax concentration and reaction time), (2) central composite design (CCD) including the effect of

Verapamil Hydrochloride (VH) has been determined spectrophotometrically by using Methyl Orange (MO).  In our previous researches MO was used for determination of Mexiletine Hydrochloride [1]. The method was based on complexation between (MO and VH).  After shaking and diluting the complex solution with D.W, the pH was adjusted with NaOH and HCl to pH 4. The colored complex formed between VH and the reagents were transferred into separating funnels and extracted using 4.5 ml CH2Cl2 and were shaken for (4 minutes).  The extracted organic layer was used for the preparation of the calibration curves for spectrophotometric measurements of VH at 437nm.  The blanks were carried out in exactly the same way throughout the whol