Hitesh Patel, Nikunj Patel, Priyanka Shah, Rohit Gajera
A novel, rapid and an accurate
reversed phase high-performance liquid chromatography (RP-HPLC) method was
developed and validated for the simultaneous quantification of emtricitabine
and tenofovir related impurities namely emtricitabine s-oxide (emtricitabine impurity-A)
and tenofovir (S)-propanol (tenofovir impurity-A), respectively in the combined
pharmaceutical dosage form of emtricitabine, dolutegravir and tenofovir alafenamide.
The separation was accomplished on Inertsil ODS C18 (250 ´ 4.6 mm, 5μ) column using 0.5 M
potassium dihydrogen phosphate buffer: acetonitrile (80: 20, v/v), pH 4.5 ± 0.1
maintained by 0.1 % o-phosphoric acid as mobile phase delivered at a flow rate of 1.0
mL/min. Detection was carried out at 260 nm. Emtricitabine impurity-A and
tenofovir impurity-A
analytes were eluted at retention times of 10.5 and 16.6 min, respectively. The
developed method was successfully validated for various parameters like system
suitability, linearity, accuracy, precision, robustness, limit of detection and
quantification in accordance with ICH guidelines. The calibration curves were
linear over the concentration range of 0.125-7.500 μg/ml for emtricitabine impurity-A
and tenofovir impurity-A with correlation coefficients ³ 0.998. The validated method was
successfully applied for the simultaneous estimation of emtricitabine s-oxide
(emtricitabine impurity-A) and tenofovir (S)-propanol (tenofovir impurity-A) in
fixed-dose combination comprising of emtricitabine,
dolutegravir and tenofovir alafenamide.
Emtricitabine,
Dolutegravir, Tenofovir Alafenamide, RP-HPLC, Method validation, Related
substances, Pharmaceutical tablets
VOL.13, ISSUE No.3, September 2021