New synergistic benzoquinone scaffolds as inhibitors of mycobacterial cytochrome bc1 complex to treat multi-drug resistant tuberculosis.

Through a comprehensive molecular docking study, a unique series of naphthoquinones clubbed azetidinone scaffolds was arrived with promising binding affinity to Mycobacterial Cytbc1 complex, a drug target chosen to kill multi-drug resistant Mycobacterium tuberculosis (MDR-Mtb). Five compounds from series-2, 2a, 2c, 2g, 2h, and 2j, showcased significant in vitro anti-tubercular activities against Mtb H37Rv and MDR clinical isolates. Further, synergistic studies of these compounds in combination with INH and RIF revealed a potent bactericidal effect of compound 2a at concentration of 0.39 µg/mL, and remaining (2c, 2g, 2h, and 2j) at 0.78 µg/mL. Exploration into the mechanism study through chemo-stress assay and proteome profiling uncovered the down-regulation of key proteins of electron-transport chain and Cytbc1 inhibition pathway. Metabolomics corroborated these proteome findings, and heightened further understanding of the underlying mechanism. Notably, in vitro and in vivo animal toxicity studies demonstrated minimal toxicity, thus underscoring the potential of these compounds as promising anti-TB agents in combination with RIF and INH. These active compounds adhered to Lipinski's Rule of Five, indicating the suitability of these compounds for drug development. Particular significance of molecules NQ02, 2a, and 2h, which have been patented (Published 202141033473).

Development and validation of high-performance liquid chromatography-Orbitrap mass spectrometric method for quantification of NDMA in ranitidine drug products and evaluation of antioxidants as inhibitors of classical nitrosation reaction.

RATIONALE: N-Nitroso dimethylamine (NDMA) is a mutagenic impurity detected in several ranitidine products. The amino functional group of ranitidine is a risk factor for classical nitrosation-induced NDMA formation in ranitidine drug products during storage conditions. The United States Food and Drug Administration (US FDA) recommended the use of antioxidants to control NDMA in drug products. Considering the need for sensitive analytics, a liquid chromatography/high-resolution mass spectrometry (LC-HRMS) method was developed and validated to detect NDMA in this pilot study to demonstrate the antioxidants as inhibitors of nitrosation reactions. METHODS: The method, utilizing an EC-C18 column and tuned to atmospheric pressure chemical ionization/selected ion monitoring (APCI/SIM) mode, separated NDMA (m/z: 75.0553; tR: 3.71 min) and ranitidine (m/z: 315.1485; tR: 8.61 min). APCI mode exhibited four times higher sensitivity to NDMA than electrospray ionization (ESI) mode. Classical nitrosation of the dimethyl amino group of ranitidine was studied with sodium nitrite in solid pellets. Antioxidants (alpha-tocopherol, ascorbic acid, and trolox) were evaluated as NDMA attenuators in ranitidine pellets under vulnerable storage conditions. The developed method quantified NDMA levels in samples, extracted with methanol through vortex shaking for 45 min. RESULTS: The method achieved a limit of detection (LOD) and limit of quantitation (LOQ) of 0.01 and 0.05 ng/mL, respectively, with linearity within 1-5000 ng/mL (R1: 0.9995). It demonstrated good intra-day and inter-day precision (% RSD [relative standard deviation]: <2) and accuracy (96.83%-101.72%). Nitrosation of ranitidine induced by nitrite was significant (p < 0.001; R2 = 0.9579) at various sodium nitrite levels. All antioxidants efficiently attenuated NDMA formation during ranitidine nitrosation. Ascorbic acid exhibited the highest NDMA attenuation (96.98%), followed by trolox (90.58%). This study recommends 1% ascorbic acid and trolox as potent NDMA attenuators in ranitidine drug products. CONCLUSIONS: This study compared the effectiveness of antioxidants as NDMA attenuators in ranitidine under storage conditions susceptible to NDMA generation. The study concluded that ascorbic acid and trolox are potent inhibitors of NDMA formation and nitrosation attenuators in ranitidine drug products.

Indigenous wisdom of a Kwatha to treat NASH: An insight into the mechanism.

ETHNOPHARMACOLOGICAL RELEVANCE: Nonalcoholic fatty liver disease (NAFLD) is the most common severe liver disease globally, progressing further into nonalcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC). Vasaguduchyadi Kwatha (VK) is an Ayurvedic formulation traditionally used to treat liver diseases and other metabolic complications. This study is an ethnopharmacological approach to unravel this indigenous remedy. AIM OF THE STUDY: We aimed to discover the probable mechanism of action of VK against NASH in this study, using network pharmacology, molecular docking, in vitro study, and preclinical investigation. METHODS AND RESULTS: Among the 55 components identified, 10 were confirmed based on mass, elution charecteristics, MS/MS analysis data, and fragmentation rules. Computational study indicated 92 targets involved in the central pathways of NASH, out of which only 15 targets and 9 VK constituents have significant docking scores. In vitro and in vivo analysis results showed that VK significantly reduces weight gain and improves insulin sensitivity, dyslipidemia, steatohepatitis and overall histological features of NASH compared to saroglitazar (SGZR). CONCLUSION: Our detailed study yielded three signalling pathways related to NASH on which VK has maximum effect, bringing up a probable alternative treatment for NASH.

Discovery and development of COVID-19 vaccine from laboratory to clinic.

The world has recently experienced one of the biggest and most severe public health disasters with severe acute respiratory syndrome coronavirus (SARS-CoV-2). SARS-CoV-2 is responsible for the coronavirus disease of 2019 (COVID-19) which is one of the most widespread and powerful infections affecting human lungs. Current figures show that the epidemic had reached 216 nations, where it had killed about 6,438,926 individuals and infected 590,405,710. WHO proclaimed the outbreak of the Ebola virus disease (EVD), in 2014 that killed hundreds of people in West Africa. The development of vaccines for SARS-CoV-2 becomes more difficult due to the viral mutation in its non-structural proteins (NSPs) especially NSP2 and NSP3, S protein, and RNA-dependent RNA polymerase (RdRp). Continuous monitoring of SARS-CoV-2, dynamics of the genomic sequence, and spike protein mutations are very important for the successful development of vaccines with good efficacy. Hence, the vaccine development for SARS-CoV-2 faces specific challenges starting from viral mutation. The requirement of long-term immunity development, safety, efficacy, stability, vaccine allocation, distribution, and finally, its cost is discussed in detail. Currently, 169 vaccines are in the clinical development stage, while 198 vaccines are in the preclinical development stage. The majority of these vaccines belong to the Ps-Protein subunit type which has 54, and the minor BacAg-SPV (Bacterial antigen-spore expression vector) type, at least 1 vaccination. The use of computational methods and models for vaccine development has revolutionized the traditional methods of vaccine development. Further, this updated review highlights the upcoming vaccine development strategies in response to the current pandemic and post-pandemic era, in the field of vaccine development.

Pentacyclic triterpenoids from the stem of Grewia bracteata Roth demonstrate promising inhibition on tumour cells.

Grewia bracteata Roth stem was investigated for its anticancer potential for the first time. Initially, polarity-guided extracts from three solvents were screened on HeLa, HCT- 116 and MCF-7 tumours cells. The results revealed that ethyl acetate extract (GSE) significantly (p < 0.05) inhibited HeLa, HCT- 116 and MCF-7 cells with respective IC50 values of 30.58, 14.26 and 22.91 µg/mL. GSE inhibited HCT-116 cells with 6- and 21-folds higher than hexane (GSN) and methanol (GSM) extracts, respectively. Hence, column chromatography of GSE was performed and fractionated to 18 fractions. The obtained fractions were further tested on HCT-116 cells. Amongst, the fractions HF6 and DF1 were active with the respective IC50 values of 25.35 and 31.28, µg/mL (p < 0.05). These active fractions were profiled using H1-NMR, C13-NMR and LC-MS/MS analysis, and found the presence of pentacyclic triterpenoids like betulin diacetate and ursolic acid.

Anticancer effect of polyphenolic acid enriched fractions from Grewia bracteata Roth on tumor cells and their p53 gene independent ROS mediated apoptosis in colon cancer cells.

It is the first report on leaves of Grewia bracteata Roth for its anticancer effect. In this study, three polarity-guided solvent extracts of Grewia bracteata leaves from n-hexane (GLH), ethyl acetate (GLE), and methanol (GLM) were screened for anticancer effects on HeLa, HCT-116, MCF-7, HCT-116 p53-/- and PC-3 cells via methyl thiazoldiphenyltetrazolium bromide (MTT) assay. Based on the results, GLM was fractionated, and the obtained fractions were tested on HCT-116 cells. Further, FT-IR, HPLC analysis, clonogenic assay, wound healing assay, DCFDA, and cell cycle experiments were conducted on HCT-116 cells. The extracts from methanol (GLM) and ethyl-acetate (GLE) demonstrated a more selective and promising inhibition on HCT-116 cells than others. Notably, GLM recorded superior inhibition on HCT-116 p53-/- than GLE. Amongst, the methanol column fraction (GMCF) showed prominent inhibition on HCT-116 (IC50:63.55 ± 0.61 µg/ml) and HCT-116 p53-/- (IC50: 84.51 ± 0.58 µg/ml) cells. Further, the test on normal cells (NKE) revealed minimal toxicity of GMCF. The phytochemical test, FT-IR, HPLC, and LC-HRMS analyses confirmed the high abundance of polyphenolic acid/polyphenols in GMCF. Further, the clonogenic and wound healing assays on HCT-116 cells were also performed. Later, the probable cell death mechanism was identified using DCFDA and cell cycle experiments. These experiments disclosed that GMCF induced HCT-116 cell death was probably due to reactive oxygen species (ROS) upregulation and cells cycle arrest at SubG0 phase. It inferred that the activity is most probably p53 independent, a tumor suppressor gene responsible for drug resistance in colon cancer.

Deuterated driven new chemical entities: An optimistic way to improve therapeutic efficacy.

In organic chemistry, the use of deuterium exchange as a tool to study the mechanism of chemical reaction has been well explored. Since two decades, the research focus on deuterated bioactive molecules has been gaining attention for investigating the therapeutic potential of deuterium replacement in a chemical structure. Recently, Food Drug Administration (FDA) approved the first deuterium-labeled drug "deutetrabenazine", and notified the deuterated drugs as new chemical entities (NCEs). Henceforth, the deuterium substitution driven structure activity relationship, preclinical pharmacokinetics, and toxicity studies were much initiated. Deuteration of a bioactive molecule often results in improved therapeutic efficacy due to the altered pharmacokinetic profile. This review provides a conceptual framework on the importance of deuterium atom in chemical structure of a drug, and its biological value in improved physiochemical properties, pharmacokinetics, biological target interaction, diagnosis, and toxicity. In addition, this review concisely updated the recent deuteration methods, chemical stability, challenges in drug development, deuterium-based imaging in diagnosis, and selected synthetic scheme of deuterated molecules.

Tinospora sinensis (Lour.) Merr alkaloid rich extract induces colon cancer cell death via ROS mediated, mTOR dependent apoptosis pathway: "an in-vitro study".

BACKGROUND: Colorectal cancer (CRC) is the second most mortality rate causing disease after lung cancer. Though there is a significant improvement in the treatment schedule offered to CRC. However, there is no notable decrease in terms of cases as well as death rate. Hence, there is an urgent need to discover novel cancer therapeutics to treat CRC. Since ancient times, the use of phytochemicals has drawn huge attention as chemo-preventive and chemotherapeutic agents. Earlier studies on Tinospora sinensis (TS) revealed the cytotoxic effect on human colorectal carcinoma (HCT-116) cells, yet the mechanism is to be uncovered. Therefore, the present study was designed to study the cell death mechanism of TS in HCT-116 cells. METHOD: Different extracts such as n-hexane, ethyl acetate, and ethanol extracts from the root part of TS were prepared using a cold maceration process. The extracts were screened against cancer cell lines by methyl thiazoldiphenyltetrazolium bromide (MTT) assay. From the result, the most active extract was subjected to gas chromatography-mass spectrometry (GC-MS) and Fourier-Transform infrared spectroscopy (FTIR) analyses to identify the major constituents. Finally, the mechanism of cytotoxicity to cancer cells for the most active extract was evaluated using various experiments such as cell cycle analysis, Annexin-V assay, and Western blot. RESULTS: The results from the MTT assay indicated that the n-hexane extract of TS inhibits the growth of HCT-116 cells more effectively than other cancer cells like Henrietta Lacks cervical cancer cells (Hela), and Michigan cancer foundation-breast cancer (MCF-7). The GC-MS and FT-IR analyses revealed the presence of alkaloids in the n-hexane extract and were responsible for the apoptosis activity in HCT-cells via reactive oxygen species (ROS) generation, and phosphoinositide 3-kinase (PI3K)/ protein Kinase B (Akt)/ mammalian target of rapamycin (mTOR) down-regulation. CONCLUSION: This study concludes that this finding is unique of its kind, and for the first time. The anticancer effect of TS root is specific to colon cancer cells (HCT-116). This distinctive finding helps the researchers to investigate further, and to identify a novel source for anti-colon cancer drug candidates in near future.

Level of adherence to anti-tubercular treatment among drug-sensitive tuberculosis patients on a newly introduced daily dose regimen in South India: A cross-sectional study.

INTRODUCTION: Tuberculosis (TB) patients on the National Tuberculosis Elimination Program (NTEP) treatment protocol receive daily doses without health professional-supervised drug intake as during the previous directly observed treatment short-course (DOTS) regimen. We aimed to measure the level of adherence to anti-tubercular treatment (ATT) and the reasons for non-adherence among drug-sensitive TB patients on a daily-dose regimen in South India. METHODS: A cross-sectional study was conducted among TB patients who received ATT as part of the standard treatment protocol in NTEP. Patients were interviewed to capture their understanding of TB, adherence, and the reason for non-adherence to ATT using validated instruments. Urine drug metabolite testing was performed using the high-performance liquid chromatography (HPLC) technique to confirm adherence. RESULTS: A total of 488 patients were recruited for the study. 64.8% of patients had 'good knowledge' about TB and ATT. According to the subjective report, 63.7% of patients were adherent, but urine drug metabolite testing revealed 53.4% adherence. A statistically significant difference (p < 0.05) exists between subjective and objective adherence measures. Patient-reported reasons for non-adherence were side effects of ATT (18.6%), loss of daily wages (15.0%), and forgetfulness (10.0%), among others. CONCLUSIONS: Nearly half of the patients were non-adherent to the daily dosing regimen. Adherence as reported by the patients is unreliable, and urine testing could be used in routine care to assess adherence. CLINICAL TRIAL REGISTRATION AND NUMBER: CTRI/2020/04/024941.

Cardioprotective potential of indol-3-carbinol against high salt induced myocardial stress and hypertrophy in Sprague dawley rats besides molecular docking on muscarinic receptor-2.

The vegetative chemical constituent, indol-3-carbinol (I-3-C) studied for its cardioprotective potential in male Sprague dawley rats. The I-3-C at 20 mg/Kg b.w, p.o significantly (p < 0.001) attenuated the high salt induced hypertrophy and produced antihypertensive effect (p < 0.001) as similar to losartan. Further, it significantly reduced the levels of C-reactive protein (p < 0.05), creatinine kinases isoenzyme (p < 0.01), serum lactate dehydrogenase (p < 0.05), myeloperoxidase (p < 0.01) and hydroxyproline (p < 0.01), subsequently increased the nitric oxide level (p < 0.05). The carotid ligation for vascular reactivity against vasopressors revealed a lesser magnitude of change (p < 0.05) in invasive blood pressure for I-3-C, compared to high salt treated animals (p < 0.001). In histology of heart tissue also supported the cardioprotective effect of I-3-C. In silico molecular docking of I-3-C on muscarinic receptor-2 showed the amino acid interaction as similar to acetylcholine.

Insights on recent approaches in drug discovery strategies and untapped drug targets against drug resistance.

BACKGROUND: Despite the various strategies undertaken in the clinical practice, the mortality rate due to antibiotic-resistant microbes has been markedly increasing worldwide. In addition to multidrug-resistant (MDR) microbes, the "ESKAPE" bacteria are also emerging. Of course, the infection caused by ESKAPE cannot be treated even with lethal doses of antibiotics. Now, the drug resistance is also more prevalent in antiviral, anticancer, antimalarial and antifungal chemotherapies. MAIN BODY: To date, in the literature, the quantum of research reported on the discovery strategies for new antibiotics is remarkable but the milestone is still far away. Considering the need of the updated strategies and drug discovery approaches in the area of drug resistance among researchers, in this communication, we consolidated the insights pertaining to new drug development against drug-resistant microbes. It includes drug discovery void, gene paradox, transposon mutagenesis, vitamin biosynthesis inhibition, use of non-conventional media, host model, target through quorum sensing, genomic-chemical network, synthetic viability to targets, chemical versus biological space, combinational approach, photosensitization, antimicrobial peptides and transcriptome profiling. Furthermore, we optimally briefed about antievolution drugs, nanotheranostics and antimicrobial adjuvants and then followed by twelve selected new feasible drug targets for new drug design against drug resistance. Finally, we have also tabulated the chemical structures of potent molecules against antimicrobial resistance. CONCLUSION: It is highly recommended to execute the anti-drug resistance research as integrated approach where both molecular and genetic research needs to be as integrative objective of drug discovery. This is time to accelerate new drug discovery research with advanced genetic approaches instead of conventional blind screening.

Beta-Alanine and Tris-(hydroxyl methyl) Aminomethane as Peak Modifiers in the Development of RP-HPLC Methods Using Aceclofenac and Haloperidol Hydrochloride as Exemplar Drugs.

In the present analytical approach, beta-alanine (ALA) and tris-(hydroxyl methyl) aminomethane (TRIS) were investigated as peak modifiers due to their water solubility and their possible peak modifying a property. These reagents were tested for their efficacy on the elution of aceclofenac (ACF) and haloperidol hydrochloride (HLC) from C18 column (250 mm × 4.6 mm, 5 µ) equipped with a photodiode array detector. The test reagents were investigated at 0.25 ± 0.05% concentration with a varying % aqueous composition on elution efficacy of HLC and ACF. The added ALA/TRIS in the mobile phase significantly (P < 0.05) improvised the symmetrical elution of HLC with 3-fold theoretical plates increase (P < 0.05) and 10-fold reduced capacity factor as compared to the control run. For ACF, the shoulder effect observed for ACF peak was eliminated. The optimized mobile phase was a combination of acetonitrile and water containing 0.25% beta-alanine/TRIS (pH 3.5 with ortho-phosphoric acid) at the ratio of 70:30 and 60:40% v/v, respectively, for ACF and HLC. The method was validated as per ICHQ2 guidelines. The column performance was tested for reproducibility in non-peak modifier applications and revealed a null effect on the column, thus these agents are relatively less toxic to HPLC columns.

In vitro antitubercular, anticancer activities and IL-10 expression in HCT-116 cells of Tinospora sinensis (Lour.) Merr. leaves extract.

Considering the importance of Tinospora sinensis in folklore as immunomodulant, the leaves subjected to cold maceration using ethanol, ethyl acetate and n-hexane and then screened for their antitubercular, anticancer and IL-10 expression (HCT-116) properties using luciferase reporter phage, MTT and flow cytometry assay methods, respectively. The results revealed that ethyl acetate and n-hexane extracts demonstrated the promising (p < 0.05) antitubercular activity with inhibition (%) of 92% and 86%, at 100 µg/ml, respectively and the respective IC50 values of 63.99 and 113.7 µg/ml on HeLa and HCT-166 cells. The n-hexane extract demonstrated the significant (p < 0.05) IL-10 expression (44.12 MFU) in HCT-116 cells against the control cells (8.48 MFU). The GC-MS analyses of n-hexane extract showed presence of tembatarine, berberine, cordifoliside E, and magnoflorine as major constituents. Among all extracts, n-hexane leaf extract was found to be potent against inhibition of colon cancer cells (HCT-116) and Mycobacteria, with significant immunostimulant activity.

Polyphenolic Nutrients in Cancer Chemoprevention and Metastasis: Role of the Epithelial-to-Mesenchymal (EMT) Pathway.

The epithelial-to-mesenchymal transition (EMT) has received significant interest as a novel target in cancer prevention, metastasis, and resistance. The conversion of cells from an epithelial, adhesive state to a mesenchymal, motile state is one of the key events in the development of cancer metastasis. Polyphenols have been reported to be efficacious in the prevention of cancer and reversing cancer progression. Recently, the antimetastatic efficacy of polyphenols has been reported, thereby expanding the potential use of these compounds beyond chemoprevention. Polyphenols may affect EMT pathways, which are involved in cancer metastasis; for example, polyphenols increase the levels of epithelial markers, but downregulate the mesenchymal markers. Polyphenols also alter the level of expression and functionality of important proteins in other signaling pathways that control cellular mesenchymal characteristics. However, the specific proteins that are directly affected by polyphenols in these signaling pathways remain to be elucidated. The aim of this review is to analyze current evidence regarding the role of polyphenols in attenuating EMT-mediated cancer progression and metastasis. We also discuss the role of the most important polyphenol subclasses and members of the polyphenols in reversing metastasis and targeting EMT. Finally, limitations and future directions to improve our understanding in this field are discussed.

New Conjugates of Quinoxaline as Potent Antitubercular and Antibacterial Agents.

Considering quinoxaline as a privileged structure for the design of potent intercalating agents, some new sugar conjugates of quinoxaline were synthesized and characterized by IR, (1)HNMR, (13)C NMR, and mass spectral data. In vitro testing for antitubercular and antimicrobial activities was performed against Mycobacterium tuberculosis H 37 Rv and some pathogenic bacteria. Results revealed that conjugate containing ribose moiety demonstrated the most promising activity against Mycobacteria and bacteria with minimum inhibitory concentrations (MIC) of 0.65 and 2.07 µM, respectively. Other conjugates from xylose, glucose, and mannose were moderately active whilst disaccharides conjugates were found to be less active. In silico docking analysis of prototype compound revealed that ATP site of DNA gyrase B subunit could be a possible site for inhibitory action of these synthesized compounds.

Re-engineering nalidixic acid's chemical scaffold: A step towards the development of novel anti-tubercular and anti-bacterial leads for resistant pathogens.

Occurrence of antibacterial and antimycobacterial resistance stimulated a thrust to discover new drugs for infectious diseases. Herein we report the work on re-engineering nalidixic acid's chemical scaffold for newer leads. Stepwise clubbing of quinoxaline, 1,2,4-triazole/1,3,4-oxadiazole with nalidixic acid yielded better compounds. Compounds were screened against ciprofloxacin resistant bacteria and Mycobacterium tuberculosis H37Rv species. Results were obtained as minimum inhibitory concentration, it was evident that molecule with quinoxaline linked azide as side chain served as antitubercular lead (<6.25 µg/ml) whilst molecule with oxadiazole or triazole linked quinoxaline side chain served as anti-bacterial lead. Few compounds were significantly active against Escherichia coli and Proteus vulgaris with MIC less than 0.06 µg/ml and relatively potent than ciprofloxacin. No true compound was potentially active against Salmonella species as compared to amoxicillin.

A stability-indicating RP-HPLC method for the quantitative analysis of meclizine hydrochloride in tablet dosage form.

A specific stability-indicating reversed-phase high-performance liquid chromatographic method was developed and validated for the estimation of meclizine hydrochloride (MEC) in tablet dosage form. The HPLC method has shown adequate separation of MEC from their degradation products. The separation was achieved on a C8 (250 mm×4.6 mm×5 µm) column using a mobile phase composition of 0.2% triethylamine in water and methanol in the ratio of 65:35(pH adjusted to 3.0 with orthophosphoric acid) with a flow rate of 1 mL/min. The wavelength of a photo-diode array detector was kept at 229 nm. Stress studies were performed initially under milder conditions followed by stronger conditions so as to get sufficient degradation around 5-20%. There were six degradation products observed with adequate separation from the analyte peak. Among those detected degradation products, structures of four degradation products were verified by comparison with known impurities of meclizine analogs. The method was validated as per the International Conference on Harmonization (Q2) guidelines. The method was specific, selective, accurate and precise to quantify meclizine in the presence of degradation products.

Analytical quality by design: a tool for regulatory flexibility and robust analytics.

Very recently, Food and Drug Administration (FDA) has approved a few new drug applications (NDA) with regulatory flexibility for quality by design (QbD) based analytical approach. The concept of QbD applied to analytical method development is known now as AQbD (analytical quality by design). It allows the analytical method for movement within method operable design region (MODR). Unlike current methods, analytical method developed using analytical quality by design (AQbD) approach reduces the number of out-of-trend (OOT) results and out-of-specification (OOS) results due to the robustness of the method within the region. It is a current trend among pharmaceutical industry to implement analytical quality by design (AQbD) in method development process as a part of risk management, pharmaceutical development, and pharmaceutical quality system (ICH Q10). Owing to the lack explanatory reviews, this paper has been communicated to discuss different views of analytical scientists about implementation of AQbD in pharmaceutical quality system and also to correlate with product quality by design and pharmaceutical analytical technology (PAT).

Identification of Degradation Products and a Stability-Indicating RP-HPLC Method for the Determination of Flupirtine Maleate in Pharmaceutical Dosage Forms.

In this stability-indicating, reversed-phase high-performance liquid chromatographic method for flupiritine maleate, forced degradation has been employed and the formed degradants were separated on a C18 column with a 80:20% v/v mixture of methanol-water containing 0.2% (v/v) triethylamine; the pH was adjusted to 3.1. The flow rate was 1 mLmin(-1) and the photodiode array detection wavelength was 254 nm. Forced degradation of the drug was carried out under acidic, basic, thermal, photolytic, peroxide, and neutral conditions. Chromatographic peak purity data indicated no co-eluting peaks with the main peaks. This method resulted in the detection of seven degradation products (D1-D7). Among these, three major degradation products from acidic and basic hydrolysis were identified and characterized by (1)H-NMR, (13)C-NMR, and mass spectral data. The method was validated as per International Conference on Harmonization guidelines (Q2). The linearity of the method was in the concentration range of 20-120 µgmL(-1). The relative standard deviations for intra- and interday precision were below 1.5%. The specificity of the method is suitable for the stability-indicating assay.