Objective: The compatibility of four binary active substances combinations adapalene – levofloxacin (ADP-LFX), adapalene – miconazole nitrate (ADP-MCZ), levofloxacin – meloxicam (LFX-MLX) and levofloxacin – miconazole nitrate (LFX-MCZ) was analysed to be comprised in new transdermal therapeutic systems. Also, the compatibility of selected active substances and four polymeric excipients (hydroxypropyl methylcellulose – HPMC 15000, hydroxypropyl methylcellulose – HPMC E5, ethyl cellulose – EC 10, and hydroxyethyl cellulose – HEC) was studied.
Methods: Thin layer chromatographic method (TLC) and four selected mobile phases were used. On the plate (in situ) were obtained the binary combinations (active substances and active substance-polymer).
Results: A good compatibility of ADP-LFX was found using ammonia : methanol : acetonitrile : methylene chloride 2:4:1:4 mobile phase. Using chloroform : acetone : glacial acetic acid 34:4:3 on the chromatogram of ADP-MCZ, only ADP spots appeared but without changes in the shape of the spots and Rf values. Any modifications of LFX and MLX spots (from LFX-MLX mixture) had been observed using toluene : glacial acetic acid : methanol 11:1:0.5 mobile phase, although LFX spots have remained on the baseline. Only LFX spots were visible from LFX-MLX and LFX-MCZ mixtures (ammonia : methanol : acetonitrile : methylene chloride 2:4:1:4 mobile phase). Distinctive spots were observed for ADP, LFX and MLX with variable results from no chemical interactions to limited chemical interactions when the compatibility with polymers was verified.
Conclusions: ADP-LFX and LFX-MLX mixtures were found to be compatible. ADP with HPMC polymers and LFX with HPMC E5 and HEC had presented excellent compatibility; for the other binary combinations, different analytical methods will be necessary.
Tag Archives: meloxicam
Validation of High Performance Liquid Chromatography Methods for Determination of Meloxicam and Tenoxicam from Transdermal Therapeutic Systems
Objective: The aim of this study was to develop and validate two HPLC methods for the quantification of meloxicam and tenoxicam from transdermal therapeutic systems.
Methods: Based on 1.0% hydroxypropyl methylcellulose 15000, transdermal patches containing meloxicam or tenoxicam were prepared by solvent evaporation technique. Analytical performances of the HPLC methods for the quantification of meloxicam and tenoxicam from such systems were assessed in terms of specificity, linearity, detection limit, quantification limit, recovery and precision.
Results and discussion: The linearity of the method was assessed through a calibration curve in the 1.0 – 75.0 μg∙mL-¹ concentration range, with a regression coefficient higher than 0.999. The detection limit and the quantification limit were found to be 0.46 μg∙mL-¹ and 1.39 μg∙mL-¹, for meloxicam; and 0.88 μg∙mL-¹, respectively 2.64 μg∙mL-¹ for tenoxicam. According to the European Pharmacopeia 5.0 the mean recovery was found to be between 75% and 125%. As performance criteria for precision was used the RSD% which were lower than 2.0% for both methods.
Conclusions: The proposed liquid chromatography methods provide selective, linear and precise results for the quantification of meloxicam and tenoxicam from transdermal therapeutic systems. The presence of a single peak in the chromatograms of the analyzed transdermal patches with meloxicam or tenoxicam, certify the successful determination of the active pharmaceutical ingredient in the prepared patches.
Development of a HPLC-UV Method for Determination of Meloxicam in Human Plasma and Pharmaceutical Dosage Forms
Objectives: A simple, quick and low cost HPLC-UV method for assay of meloxicam in plasma and pharmaceutical dosage forms was developed.
Methods: Separation and assay of meloxicam, using a simple reverse phase HPLC-UV method was achieved using an Agilent Zorbax SB C18 column, with methanol and 1% aqueous solution of glacial acetic acid as mobile phase. Elution was performed with composition gradient, meloxicam being detected at 355 nm with a 5 minutes analysis time. The method was tested on human plasma and pharmaceutical dosage forms.
Results: The retention time of the meloxicam was 3,7 minutes. Regression analysis showed good linearity, with correlation coefficient R= 0,9997; linear regression equation: y = 206,1x –77,5 over the 20-2000 ng/ml concentration range. Limit of detection was determined to be 5 ng/ml and limit of quantification was set at 15 ng/ml. The recovery of the analyte in human plasma was low: 30,50%, however it was reproducible, with a coefficient of variation of 4,83%. The analysis of the tablets resulted in a 85,82% of meloxicam compared to the declared concentration.
Conclusions: The method proposed is quick, simple and adequate for detecting the meloxicam in human plasma. Although the recovery rate was low, it was reproducible, which leads to the fact, that improving extraction procedure can optimize the method.