The identification and the quantitative determination of loratadine by the HPLC method

Abstract

Aim. To develop the unified method of the HPLC analysis of loratadine, which can allow obtaining reliable and reproducible results of the studies of pharmaceuticals and biological matrices for monitoring the treatment effectiveness. Materials and methods. The HPLC analysis was performed on a “Milichrome A-02” microcolumn liquid chromatograph under the following conditions: a reversed-phase variant, 2×75 mm column filled with a non-polar sorbent Prontosil 120-5 C18 AQ, 5 μm; the mobile phase in the mode of a linear gradient – from eluent А (5% of acetonitrile and 95% of a buffer solution) to eluent B (100% of acetonitrile) for 40 min. The flow rate of the mobile phase was 100 μL/min; the injection volume was 4 μL. The multichannel detection of the substance was carried out using an UV-detector at 210, 220, 230, 240, 250, 260, 280 and 300 nm; the optimal value of the column temperature was 37–40 °С, and the pump pressure was 2.8–3.2 MPa. Results and discussion. As a result of the studies performed, the retention parameters of loratadine and spectral relationships were determined using the unified HPLC method. This made it possible to include the results obtained in the database for the identification of antihistamines in the therapeutic monitoring of the treatment with an individual drug or in the complex treatment of allergic reactions. The development of the quantitative determination of loratadine by HPLC on model solutions using various concentrations of the drug was carried out. The content of loratadine was determined by the equation S = 1.14 × 10^(-3)C – 0.50 × 10^(-4); the correlation coefficient was 0.9998. It was found that the relative standard deviation RSD did not exceed 0.93 % when analyzing loratadine in the model solutions by HPLC. Conclusions. The identification and the quantitative determination of loratadine by the unified HPLC method have been conducted. The method allows obtaining reliable and reproducible research results. The results of the studies can be recommended for implementation in the practice of forensic bureaus, toxicological centers, and clinical laboratories.

Keywords

• loratadine
• identification
• quantitative determination
• high-performance liquid chromatography