Simultaneous Determination of Rofecoxib and Tizanidine by HPTLC

Abstract: An innovative high performance thin layer chromatography method was developed and validated for simultaneous determination of rofecoxib and tizanidine from tablet dosage form. Rosiglitazone maleate was used as an internal standard. The separation was achieved using HPTLC plates (Merck #5548) precoated with silica gel 60F 254 on aluminum sheets and a mobile phase comprising of toluene: ethyl acetate: methanol: triethyl amine in volume ratio of 6:3:0.5:0.1 (v/v/v/v), with chamber saturation of 15 min. The plate was developed up to 8 cm and air dried. The plate was then scanned and quantified at 235 nm. The linearity of rofecoxib and tizanidine were in the range of 3.75 µg/spot to 11.25 µg/spot and 0.30 µg/spot to 0.90 µg/spot respectively. The limit of detection for rofecoxib and tizanidine was found to be 45.00 ng/spot and 30.00 ng/spot respectively. The limit of quantification for rofecoxib and tizanidine was found to be 135.00 ng/spot and 90.00 ng/spot respectively. The percentage assay was found between the range of 99.58% to 103.21% for rofecoxib and 98.73% to 101.55% for tizanidine respectively, whereas recovery was found between 99.97% to 100.43% for rofecoxib and 100.00% to 101.00% for tizanidine by standard addition method. The proposed method is accurate, precise and rapid for the simultaneous determination of rofecoxib and tizanidine in dosage form

Simultaneous Determination of Aceclofenac, Paracetamol and Chlorzoxazone by HPLC in Tablet Dose Form

A simple, fast and precise reversed phase high performance liquid chromatographic method is developed for the simultaneous determination of aceclofenac, paracetamol and chlorzoxazone. Chromatographic separation of the three drugs was performed on an Intersil C18 column (250 mm × 4.6 mm, 5µm) as stationary phase with a mobile phase comprising of 10 mM potassium dihydrogen phosphate (pH adjusted to 5.55 with ammonia): acetonitrile in the ratio 60:40 (v/v) at a flow rate of 1.0 mL/min and UV detection at 205 nm. The linearity of aceclofenac, paracetamol and chlorzoxazone were in the range of 5.00-15.00 µg/µL, 25.00-75.00 µg/µL and 25.00-75.00 µg/µL respectively. The limit of detection for aceclofenac, paracetamol and chlorzoxazone was found to be 18.0 ng/mL, 22.0 ng/mL and 9.0 ng/mL respectively whereas, the limit of quantification was found to be 55 ng/mL, 65 ng/mL and 27.0 ng/mL respectively. The recovery was calculated by standard addition method. The average recovery was found to be 99.04%, 99.57% and 101.63% for aceclofenac, paracetamol and chlorzoxazone respectively. The proposed method was found to be accurate, precise and rapid for the simultaneous determination of aceclofenac, paracetamol and chlorzoxazon

Simultaneous Determination of Aceclofenac, Paracetamol and Chlorzoxazone by HPLC in Tablet Dose Form

A simple, fast and precise reversed phase high performance liquid chromatographic method is developed for the simultaneous determination of aceclofenac, paracetamol and chlorzoxazone. Chromatographic separation of the three drugs was performed on an Intersil C18 column (250 mm × 4.6 mm, 5µm) as stationary phase with a mobile phase comprising of 10 mM potassium dihydrogen phosphate (pH adjusted to 5.55 with ammonia): acetonitrile in the ratio 60:40 (v/v) at a flow rate of 1.0 mL/min and UV detection at 205 nm. The linearity of aceclofenac, paracetamol and chlorzoxazone were in the range of 5.00-15.00 µg/µL, 25.00-75.00 µg/µL and 25.00-75.00 µg/µL respectively. The limit of detection for aceclofenac, paracetamol and chlorzoxazone was found to be 18.0 ng/mL, 22.0 ng/mL and 9.0 ng/mL respectively whereas, the limit of quantification was found to be 55 ng/mL, 65 ng/mL and 27.0 ng/mL respectively. The recovery was calculated by standard addition method. The average recovery was found to be 99.04%, 99.57% and 101.63% for aceclofenac, paracetamol and chlorzoxazone respectively. The proposed method was found to be accurate, precise and rapid for the simultaneous determination of aceclofenac, paracetamol and chlorzoxazon