Objectives: The aim of the study was to propose a new UHPLC method for the determination of cannabidiol (CBD) from supplements and drugs available on the Romanian market. Materials and methods: The HPLC assay of CBD was achieved by using a Phenomenex Gemini NX-C18 column. The mobile phase consisted of 70% acetonitrile and 30% water. Elution was performed in isocratic mode and the detection was done at 208 nm. The method was tested on hard capsules containing 150 mg of CBD.
Results and discussions: The retention time of CBD was 2.8 minutes. Regression analysis showed good linearity over the 1-100 ug/ml concentration range. The lowest limit of quantification was established at 1 µg/ml. The method was developed by using reconstituted capsules. The substance proved low stability in solution at room temperature and stability at temperatures between 2-8ºC. The recovery of reconstituted samples was 96.77%. The commercial capsules had a very low content of 15-20% from declared content.
Conclusions: The proposed method can be used for CBD determination in different pharmaceutical formulations – hard and soft capsules with coconut oil as excipient.
Tag Archives: assay
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.