LC-MS-MS Characterization of Forced Degradation Products of Fidarestat, a Novel Aldose Reductase Inhibitor: Development and Validation of a Stability-Indicating RP-HPLC Method.

An accurate, precise, robust and selective stability-indicating liquid chromatographic (LC) method has been developed for the monitoring of fidarestat in the presence of its forced degradants. The drug was subjected to hydrolysis (acid, alkali and neutral degradation), oxidation, photolysis and thermal stress conditions. The drug degraded significantly under hydrolytic (basic, acidic and neutral) and oxidative stress conditions, whereas it was found to be stable in photolytic and thermal conditions. The chromatographic separation was achieved on a Grace C18, (250 mm × 4.6 mm × 5 μm) column using gradient mobile phase system consisting of 10 mM of ammonium acetate buffer at pH 4 and acetonitrile at a flow rate of 1 mL/min with UV detection at 283 nm. The developed method was extended to liquid chromatography quadrupole time-of-flight tandem mass spectrometry (LC-QTOF-MS-MS) for characterization of all the degradation products. A total of five new degradation products were identified and characterized by LC-QTOF-MS-MS. The developed LC method was validated as per ICH guideline Q2 (R1). The proposed method was found to be successively applied for the quality control of fidarestat in bulk drug analysis.

Talluri MV ，Khatoon L ，Kalariya PD ，Chavan BB ，Ragampeta S ... -  《-》

Validated stability indicating assay method of olaparib: LC-ESI-Q-TOF-MS/MS and NMR studies for characterization of its new hydrolytic and oxidative forced degradation products.

Olaparib (OLA) is a poly ADP ribose polymerase (PARP) enzyme inhibitor used to treat prostate, ovarian and breast cancer. The drug substance OLA was subjected to forced degradation as per ICH prescribed guidelines. It was degraded in hydrolytic (acidic and basic) and oxidative stress conditions and yielded four degradation products (DPs) while it remained stable in neutral hydrolytic, dry heat and photolytic stress conditions. A stability indicating assay method was developed to separate OLA and its DPs using InertSustain C18 column (250 × 4.6 mm, 5 μm) with a gradient mobile phase of 10 mM ammonium acetate (pH 4.5) and acetonitrile (ACN) at a flow rate of 1 mL min-1. The characterization of DPs was carried out by using liquid chromatography-electrospray ionization-quadrupole-time of flight tandem mass spectrometry (LC-ESI-Q-TOF-MS/MS). Major degradation products (DP-1 and DP-2) were isolated by using preparative HPLC and structures were further confirmed by using NMR spectroscopy. All the obtained DPs were new and not reported previously. The developed chromatographic method was validated as per ICH Q2 (R1) guideline and USP general chapter on method validation.

Thummar M ，Kuswah BS ，Samanthula G ，Bulbake U ，Gour J ，Khan W ... -  《-》

Structural characterization of alkaline and oxidative stressed degradation products of lurasidone using LC/ESI/QTOF/MS/MS.

A selective, accurate, precise and robust stability indicating liquid chromatography assay method was developed for the monitoring of a novel antipsychotic drug, lurasidone, in the presence of its degradation products (DPs). Also, we investigated degradation behavior of the drug under various stressed conditions such as hydrolytic (acidic, basic and neutral), oxidation, photolytic and thermal. The drug was found to be degraded under base hydrolytic and oxidative conditions, while it was stable in acid and neutral hydrolytic, photolytic and thermal conditions. The method showed adequate separation of lurasidone and its DPs on Xterra C18 (150 mm × 4.6 mm i.d., 3.5 μm) column using 20 mM ammonium formate (pH 3.0): acetonitrile as a mobile phase in gradient elution mode at a flow rate of 0.6 mL/min. This method was extended to liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (LC/ESI/QTOF/MS/MS) for structural characterization of DPs. A total of five DPs were characterized by LC/ESI/QTOF/MS/MS studies. Most probable mechanisms for the formation of DPs were proposed. The developed method was validated in terms of specificity, linearity, accuracy, precision, and robustness as per International Conference on Harmonization Guideline Q2 (R1).

Kumar Talluri MVN ，Dharavath S ，Kalariya PD ，Prasanth B ，Srinivas R ... -  《-》

Identification and characterization of stressed degradation products of prulifloxacin using LC-ESI-MS/Q-TOF, MSn experiments: development of a validated specific stability-indicating LC-MS method.

A rapid, specific and novel gradient LC-MS method has been developed and validated for the identification and characterization of stressed degradation products (DPs) of prulifloxacin (PF) using liquid chromatography combined with quadrupole time-of-flight electrospray ionization tandem mass spectrometry (LC/Q-TOF-ESI-MS/MS). PF was subjected to hydrolytic (acidic, alkaline and neutral), oxidation, photolytic and thermal stress, as per ICH guidelines Q1A (R2). The drug showed extensive degradation in hydrolytic and oxidative, while it was stable to thermal and photolytic stress conditions. In total, 13 DPs were formed and the chromatographic separation of drug and its DPs was achieved on a C-18 column (4.6 × 250 mm, 5 μm) using gradient elution method. All the DPs have been identified and characterized using MS(n) experiments and accurate mass measurements. The LC-MS method was validated with respect to specificity, linearity, accuracy, precision and robustness.

Raju B ，Ramesh M ，Srinivas R ，Raju SS ，Venkateswarlu Y ... -  《-》

Characterization of degradation products of ivabradine by LC-HR-MS/MS: a typical case of exhibition of different degradation behaviour in HCl and H2SO4 acid hydrolysis.

A validated stability-indicating HPLC method was established, and comprehensive stress testing of ivabradine, a cardiotonic drug, was carried out as per ICH guidelines. Ivabradine was subjected to acidic, basic and neutral hydrolysis, oxidation, photolysis and thermal stress conditions, and the resulting degradation products were investigated by LC-PDA and LC-HR-MS/MS. The drug was found to degrade in acid and base hydrolysis. An efficient and selective stability assay method was developed on Phenomenex Luna C18 (250 × 4.6 mm, 5.0 µm) column using ammonium formate (10 mM, pH 3.0) and acetonitrile as mobile phase at 30 °C in gradient elution mode. The flow rate was 0.7 ml/min and detection wavelength was 286 nm. A total of five degradation products (I-1 to I-5) were identified and characterized by LC-HR-MS/MS in combination with accurate mass measurements. The drug exhibited different degradation behaviour in HCl and H2SO4 hydrolysis conditions. It is a unique example where two of the five degradation products in HCl hydrolysis were absent in H2SO4 acid hydrolysis. The present study provides guidance to revise the stress test for the determination of inherent stability of drugs containing lactam moiety under hydrolytic conditions. Most probable mechanisms for the formation of degradation products have been proposed on the basis of a comparison of the fragmentation pattern of the drug and its degradation products. In silico toxicity revealed that the degradation products (I-2 to I-5) were found to be severe irritants in case of ocular irritancy. The analytical assay method was validated with respect to specificity, linearity, range, precision, accuracy and robustness.

Patel PN ，Borkar RM ，Kalariya PD ，Gangwal RP ，Sangamwar AT ，Samanthula G ，Ragampeta S ... -  《-》