Research paper description Dr. SVG
                     Research paper of Dr. Santosh V. Gandhi for the month of July 2021
Title:  Development of Validated Stability-indicating RP-HPLC Method for Determination of 
Novel Directly Acting Antiviral agent and Characterization of its Degradants by LC–ESI–MS.
Authors: Babita Agarwal, Santosh Gandhi
Journal Details:  Indian Journal of Pharmaceutical Education and Research | Vol 54 | Issue 4 | 
Oct-Dec, 2020 1159-1168
Publisher: Association of Pharmaceutical Teachers of India.
Description:
The current study was performed to develop and validate stability indicating high performance
liquid chromatography method (RP-HPLC) for determination of ledipasvir  (LPR); to identify
and characterize its major degradants by liquid chromatographic– tandem mass spectrometric
method  (LC-ESI-MS).  The  method  was  developed  using  reverse  phase  gradient  elution  and
validated  for  standard  ICH  parameters.  The  optimized  mobile  phase  comprised  of
acetonitrile:water with 0.2 % formic acid (70:30% v/v) at 1 ml/min flow rate with satisfactory
retention time (tR), theoretical plates and good resolution of LPR and its degradants. Further,
forced  degradation  under  acid,  base,  thermal,  photolytic  and oxidative  stress  conditions  was
studied as per ICH guidelines. LC-ESI-MS with time of flight analyser was used to characterize
the degradants. The degradation pathways for major degradants were proposed. The developed
method had retention time of 6 mins. The RSD for system was found to be less than 2% whereas
mean recovery was obtained 97.2 – 102.5%. Linearity range of 5-30 μg/ml with 0.998 regression
coefficient (R2) was observed. Detection and quantification limits were obtained as 0.010 μg/mL
and 0.032 μg/mL, respectively. LPR was stable in photolytic and thermal environments whereas
degraded  in  acid,  base  and  oxidative  states.  LC–ESI–MS  was  used  effectively  for
characterization and structural elucidation of degradants. The results indicated that validated RP-
HPLC technique can be employed for routine analysis of LPR in bulk and dosage formulas and
also would be capable of separating degradants from analyte peak.
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