Design, synthesis, and pharmacological evaluation of [1, 3] dioxolo-chromeno[2,3-b]pyridines as anti-seizure agents.

An efficient one-pot three-component reaction for the synthesis of [1,3]dioxolo[4',5':6,7]chromeno[2,3-b]pyridines 4(a-i) has been developed. Synthesis was achieved by reacting sesamol (1), aromatic aldehydes 2(a-i), and 2-aminopropene-1,1,3-tricarbonitrile (3) in the presence of triethylamine at 100 °C under neat reaction condition. Simple operational procedure, broad substrate scope, column chromatography free separations, and high yield of products make it an efficient and largely acceptable synthetic strategy. Synthesized compounds 4(a-i) were further screened for preliminary anticonvulsant activity using MES and scPTZ tests. These analogs were also checked for neurotoxicity and hepatotoxicity. Selected active compounds have been then screened quantitatively to determine ED50 and TD50 values. Analog 4h was found effective in both preclinical seizure models with significant therapeutic/toxicity profile (4h: ED50 = 34.7 mg/kg, MES test; ED50 = 37.9 mg/kg, scPTZ test; TD50 = 308.7 mg/kg). Molecular dynamic simulation for 100 ns of compound 4h-complexed with GABAA receptor revealed good thermodynamic behavior and fairly stable interactions (4h, Docking score = - 10.94). In conclusion, effective synthetic strategy, significant anticonvulsant activity with good toxicity profile and detailed molecular modeling studies led us to anticipate the emergence of these analogs as valid leads for the development of future effective neurotherapeutic agents.

A brief review on critical analytical aspects for quantification of ambroxol in biological samples.

Ambroxol (AMB) is a member of the expectorant class, widely used as a secreolytic agent in patients to break up secretions. AMB is rapidly and effectively distributed from blood to tissue. The lungs have the highest concentration of AMB; accumulation of AMB in human lung tissue was detected at concentrations 15- to 20-fold greater than those reported in the circulation. Because of its wide range of actions and therapeutic applications may be worth looking into, particularly for respiratory symptoms, antioxidant, anti-inflammatory, influenza, and rhinovirus infections. Though several analytical methodologies have been established and confirmed for the AMB analysis in matrices of pharmaceutical and biological origins, novel sustainable, and economical methods are still to be choice of protocol to increase its sensitivity, reliability, and repeatability. Therefore, the present review offers an overview of critical analytical aspects regarding the HPLC, LC-MS/MS, HPTLC, capillary electrophoresis, spectrophotometry, and electrochemical methods for quantifying AMB in pharmaceutical and biological samples. Furthermore, this review will thoroughly discuss the physicochemical properties, stability, extraction conditions, instrumentation, and operational parameters of the targeted analyte. As a result, for the first time, this review complies with vital background information and an up-to-date interpretation of research undertaken by anticipated methodologies examined and implemented for the pharmaceutical analysis AMB.

Exploring an experimental combination of analytical quality by design and green analytical chemistry approaches for development of HPTLC densitometric protocol for the analysis of barnidipine hydrochloride.

An experimental combination of analytical quality by design and green analytical chemistry approaches is introduced to develop an high-performance thin-layer chromatography (HPTLC) approach to quantify barnidipine hydrochloride in the pharmaceutical matrix. The analytical quality by design approach was introduced to green analytical chemistry to enhance protocol knowledge while ensuring efficiency and reducing environmental impacts, energy consumption and analyst visibility. This analytical approach was systematically addressed by exploring failure mode effect analysis, risk assessment and optimization design. Subsequently, a screening of primary variables was performed to select the aptest proportion of solvents in the mobile phase resulting from the principles of green analytical chemistry. Failure mode effect analysis and a risk assessment study were attempted to estimate the critical method parameters (CMPs). The influence of the CMPs on critical analytical attributes, i.e. retention factor and peak area, was assessed through a screening design. A response surface methodology was then executed for the critical analytical attributes as a concern of the determined CMPs, and the conditions for excellent resolution were determined using a desirability procedure. The established protocol was validated in compliance with the International Conference on Harmonization guideline Q2(R1) and showed excellent specificity and sensitivity.

HPLC-PDA identification and resolution of rufinamide forced degradation impurities: A congregated chemometric expedite optimization coupled with factorials and desirability.

Rufinamide is used presently to treat Lenaux-Gastaut syndrome. A full factorial design and desirability approach was investigated for the optimization of hydrolytic stress via response surface curves (RSCs). The degradation impurities were identified and resolved using reversed-phase high-performance liquid chromatography (RP-HPLC) on the Qualisil® BDS C8 column. Acetonitrile-water (29:71, v/v) was optimized for the mobile phase and used at a flow rate of 1.0 ml/min with detection at a wavelength of 230 nm. Rufinamide showed appreciable susceptibility to hydrolysis under acidic and alkaline stress, and substantial degradation in the neutral condition. It degraded much less under oxidative stress. Exposure towards thermal and photolytic stress conditions indicated appreciable stability. The developed method was subjected to validation as per the recommendations of the International Conference on Harmonization. The proposed method showed no influence from the excipients and the degradation products. As well as good precision and accuracy in determination, the method showed a linear response between 2 and 12 µg ml-1 . The method was extended for determination in a human plasma sample, which resulted in excellent recovery without interference from matrix effects. The combined use of desirability and design for the optimization of acidic and alkaline hydrolytic stress led to simple and rapid analysis.

Standardization of homeopathic mother tincture of Toxicodendron pubescens and correlation of its flavonoid markers with the biological activity.

BACKGROUND: Standardization and quality control of homeopathic drugs is very challenging. As mother tinctures are derived from complex natural resources, there is a need of systematic evaluation of chemical markers which correlate with the proposed biological activities of mother tinctures. METHODS: In present study, High-Performance Thin-Layer Chromatography (HPTLC) standardization method of homeopathic mother tinctures of Toxicodendron pubescens using quercitrin and rutin as chemical markers is validated and correlations of content of these markers with its anti-inflammatory effects are established. For HPTLC analysis, precoated silica gel plates were used as stationary phase. Two flavonoids, namely quercitrin and rutin were used as markers. Separation was achieved using methylene chloride:methanol:water:glacial acetic acid (15:1.5:1:8 v/v/v) as mobile phase. The developed plates were scanned at 365 nm. RESULTS: It was observed that quercitrin (Rf value 0.63) and Rutin (Rf value 0.41) are well resolved. The minimum detectable concentrations for quercitrin and rutin were 5 ng/spot. The linearity range was between 100 and 2000 ng/spot for both the markers. Subsequently, anti-inflammatory activity of these formulations was determined against carrageenan-induced paw edema in rats, pain threshold determined by electronic Von-Frey apparatus and paw withdrawal latency (PWL) on hot-plate. All the tested formulations of Rhus Tox showed anti-inflammatory and analgesic activity against carrageenan induced paw edema in rats. Quantitative correlation between the content of markers and anti-inflammatory activity of mother tinctures was established. RESULTS: Anti-inflammatory effect as well as effect on paw withdrawal and pain threshold, at third hour after carrageenan injection, correlated with quercitrin and rutin content in the respective formulations. CONCLUSIONS: This study validates a quantitative HPTLC method for standardization of homeopathic mother tincture of Rhus Tox and establishes quercitrin and rutin as markers corresponding its biological activity. Contents of quercitrin and rutin in T. pubescens mother tincture correlates with its anti-inflammatory and analgesic actions and the validated HPTLC method can be used in standardization of homeopathic mother tincture of T. pubescens.

Eco-friendly hydrotropic spectrophotometric analysis of ranolazine hydrochloride.

Simple and eco-friendly biodegradable hydrotropes-assisted spectrophotometric experiments have been designed and validated to quantify ranolazine hydrochloride (RAN.HCl) in extended-release tablets. The citric acid and sodium citrate are employed as hydrotropes, serving as promising alternatives to polar organic solvents. The development of rapid and specific spectrophotometric experiments aimed at enhancing the spectral absorption of RAN.HCl. The spectrophotometric experiments are D0 and D0 AUC, in which the highest peak absorbance was observed at 270.50 nm, with an AUC ranging from 265.00 to 275.50 nm. Moreover, spectral analysis of D1 and D2 were conducted with peak amplitudes recorded at 280.00 nm and 274.40 nm, respectively. The AUC in the wavelength ranges 275.00-287.00 nm for D1, and 265.00-279.50 nm for D2 were implemented to quantify RAN.HCl confirms no interference from the common additives incorporated into the marketed preparation. The optimized experiments disclosed a linear relationship in the 0.02-0.16 mg/mL concentration range. The accuracy was performed at 50-150 %, revealing an overall average recovery of 100.02 %. The lowest limits of RAN.HCl that could be accurately detected and quantified were 0.0016 and 0.0049, 0.0018 and 0.0055, 0.0058 and 0.0176, 0.0024 and 0.0075, 0.0074 and 0.0224, 0.0021 and 0.0064 mg/mL, respectively, across these investigations. Statistical analysis revealed no significant differences between the outcomes of the present investigation and those documented in literature reports, based on the t- and F-values at p = 0.05, which were below the theoretical values of 2.2622, 2.3646, 6.26, and 19.20, respectively.

Nanostructured Etodolac Carriers in Transdermal Gel: Optimization and Characterization.

AIMS: To optimize, formulate, and evaluate a Nanostructured Lipid Carrier (NLC) based transdermal gel of Etodolac (ETD). OBJECTIVE: To avoid issues of conventional route ETD administration like first pass metabolism, gastric ulceration, hemorrhage, and being a class-II drug with less solubility. A transdermal gel of nanostructured lipid carrier for ETD has been developed. Formulation will execute faster onset of action, increased penetration, permeation with extended release of the drug for a longer duration. METHODS: A central composite 32 factorial design is used to plan experiments. NLCs are prepared by the method of melt emulsification and ultrasonication. Compritol 888ATO and Miglyol are used as solid and liquid lipid phases. Surfactant Pluronic F68 showed a significant effect on particle size, entrapment efficiency, and drug release. Particle size characterized using photon correlation spectroscopy and scanning electron microscopy. Cumulative drug release studied using an artificial diffusion cell and a dialysis membrane. A skin permeation study was performed using goat skin at 32°C ± 0.5°C. The efficacy of the NLC gel was verified using a pharmacodynamic study followed by stability study for 3 and 6 months. RESULTS: The optimized batch of ETD NLC found spherical with a 241.3 nm particle size with 0.392 PDI,-29 mV zeta potential. Entrapment efficiency and cumulative drug release were found to be 64.21 ± 1.23% and 70.12 ± 2.10% (after 12 hours), respectively. All batches followed zeroorder drug release kinetics and non-Fickian (Super Case II transport) with 0.1619 mg/cm2/hr transdermal flux. The NLC gel of ETD showed a quick onset and lengthened therapeutic activity until 24 hours compared to the micellar ETD gel. CONCLUSION: Etodolac NLC batch successfully optimized using central composite design. The relationships between the components of the NLC-total lipid:drug and surfactant-and the outcomes- particle size,%entrapment and% drug release-were better understood by examining several contour plots. The results of the experimental and predicted formulations were found to be in good agreement with slight bias, demonstrating the reliability of the optimization process.

Self-microemulsifying Drug Delivery System for Solubility and Bioavailability Enhancement of Eprosartan Mesylate: Preparation, In-vitro, and In-vivo Evaluation.

BACKGROUND: Formulations of eprosartan mesylate with a surfactant, like Kolliphor HS 15, an oil phase like Labrafil M 1944 CS, and a cosurfactant Transcutol HP by employing a liquid self-microemulsifying drug delivery system (SMEDDS) after screening several vehicles have been studied. OBJECTIVE: This study aimed to prepare a liquid self-microemulsifying drug delivery system for increasing the solubility and bioavailability of a poorly water-soluble eprosartan mesylate. METHODS: The micro-emulsion unit, achieved through the phase diagram and augmented with the central-composite design (CCD) surface response process, was adjusted into SMEDDS by lyophilization using sucrose as a cryoprotective agent. Particle size, self-emulsification time, polydispersion index (PDI), zeta potential, differential scanning calorimeter (DSC) screening, in-vitro drug release, and in-vivo pharmacokinetics were the essential features of the formulations. The subsequent DSC experimentation indicated that the drug was integrated into S-SMEDDS. Eprosartan mesylate loaded SMEDDS formulation showed greater in-vitro and in-vivo drug release than conventional solid doses. RESULTS: SMEDDS has reported effectiveness in reducing the impact of pH of eprosartan mesylate, thereby improving its release efficiency. The HPLC method was successfully implemented to assess eprosartan mesylate concentration in Wister rat plasma after oral administration of commercial tablet EM, SMEDDS, and eprosartan mesylate. The pharmacokinetics parameters for rats were Cmax 1064.91 ± 225 and 1856.22 ± 749 ngmL-1, Tmax 1.9 ± 0.3 hr, and 1.2 ± 0.4 hr and AUC0~t were 5314.36 ± 322.61 and 7760.09 ± 249 ng/ml hr for marketed tablets and prepared SSMEDDS, respectively. When determined by AUC0~1, the relative bioavailability of eprosartan mesylate S-SMEDDC was 152.09 ± 14.33%. CONCLUSION: The present study reports the formulation of a self-microemulsifying drug delivery system for enhancing the solubility and bioavailability of a poorly water-soluble eprosartan mesylate in an appropriate solid dosage form.

A Brief Review on Determination of Acenocoumarol in Biological and Pharmaceutical Specimens: Analytical Methodologies.

Acenocoumarol is an oral anticoagulant medicinal agent is frequently prescribed for the prophylaxis and the management of thromboembolic events. Acenocoumarol is prescribed in the form of racemic mixture and S- form is a more influential isomer. Acenocoumarol starts quickly with action and absorption, and the effect lasts for 15-20 h. In most patients, the therapeutic prothrombin range is caused 36 h after the primary dose. This review offers a detailed overview of the various analytical methodologies published in the literature from 1976 to uptil now for evaluation acenocoumarol and its combinations in specimens. The present review also stated the chiral analytical methods for the quantification of its enantiomers. A detailed study of the work revealed several analytical methodologies are routinely used for estimation of acenocoumarol includes UV/Vis-Spectrophotometry, liquid chromatography-mass spectrophotometry, high-performance liquid-chromatography, gas chromatography, high-performance thin-layer chromatography, capillary electrophoresis, Fourier-transform infrared spectroscopy and many miscellaneous techniques. Pharmaceutical analysis carried out the prominent task to understand the knowledge of the physicochemical properties of the medicinal agent; since the establishment of a new analytical method is still a challenging task for a research scientist. Thus, the present review will help to research scientist for the development of new analytical methods for the acenocoumarol.

Terahertz Spectroscopy: Encoding the Discovery, Instrumentation, and Applications toward Pharmaceutical Prospectives.

Terahertz (THz) spectroscopy is an emerging field for quality control of pharmaceuticals, which uses T-waves for detection. T-waves fall in between infrared and microwave radiations while possessing some of the characteristics of both. THz spectroscopy reveals its existence in between 0.1 and 10 THz. These radiations have the ability to penetrate a broad range of non-conductive materials and it is nonionizing. The first article stating the use of THz radiations was found in late 1960 for the generation of the astronomical images. This review essentially creates attention toward different forms and instrumentation of THz spectroscopy along with the updates for timely and upbeat pharmaceutical applications. The most frequently used technique is THz-TDS which has profoundly privileged applicability for the pharmaceuticals. The existing literature of THz spectroscopy further created albeit interest to explore the applications for future implementation in concern with the pharmaceuticals. The review critically outlines here all the pharmaceutical applications of THz spectroscopy including protein analyses, crystallinity studies, evaluating tablet films and coats, medicinal aging variations, and detection of illicit drugs, along with the advantages over traditional techniques. The other side of THz spectroscopy stating limitations is also studied and taken into the note to present here. This review is a genuine attempt to quote and crucially assess the possible as well as anticipated prospectives for the pharmaceuticals. The present article will further promote the awareness, opportunities, and scientific exploration of this exciting technology as THz spectroscopy.

Discovery and Anticancer Activity of Novel 1,3,4-Thiadiazole- and Aziridine-Based Indolin-2-ones via In Silico Design Followed by Supramolecular Green Synthesis.

Three crucial anticancer scaffolds, namely indolin-2-one, 1,3,4-thiadiazole, and aziridine, are explored to synthesize virtually screened target molecules based on the c-KIT kinase protein. The stem cell factor receptor c-KIT was selected as target because most U.S. FDA-approved receptor tyrosine kinase inhibitors bearing the indolin-2-one scaffold profoundly inhibit c-KIT. Molecular hybrids of indolin-2-one with 1,3,4-thiadiazole (IIIa-m) and aziridine (VIa and VIc) were afforded through a modified Schiff base green synthesis using ß-cyclodextrin-SO3H in water as a recyclable proton-donor catalyst. A computational study found that indolin-2,3-dione forms a supramolecular inclusion complex with ß-cyclodextrin-SO3H through noncovalent interactions. A molecular docking study of all the synthesized compounds was executed on the c-KIT kinase domain, and most compounds displayed binding affinities similar to that of Sunitinib. On the basis of the pharmacokinetic significance of the aryl thioether linkage in small molecules, 1,3,4-thiadiazole hybrids (IIIa-m) were extended to a new series of 3-((5-(phenylthio)-1,3,4-thiadiazol-2-yl)imino)indolin-2-ones (IVa-m) via thioetherification using bis(triphenylphosphine)palladium(II)dichloride as the catalyst for C-S bond formation. Target compounds were tested against NCI-60 human cancer cell lines for a single-dose concentration. Among all three series of indolin-2-ones, the majority of compounds demonstrated broad-spectrum activity toward various cancer cell lines. Compounds IVc and VIc were further evaluated for a five-dose anticancer study. Compound IVc showed a potent activity of IC50 = 1.47 µM against a panel of breast cancer cell lines, whereas compound VIc exhibited the highest inhibition for a panel of colon cancer cell lines at IC50 = 1.40 µM. In silico ADME property descriptors of all the target molecules are in an acceptable range. Machine learning algorithms were used to examine the metabolites and phase I and II regioselectivities of compounds IVc and VIc, and the results suggested that these two compounds could be potential leads for the treatment of cancer.

Antidiarrheal activity, chemical and toxicity profile of Berberis aristata.

CONTEXT: This study evaluated the in vitro and in vivo antidiarrheal activity, oral acute toxicological profile, and developed a chemical fingerprint of Berberis aristata Linn. (Berberidaceae). MATERIALS AND METHODS: The ethanol (by maceration) and aqueous (by Soxhlet) extracts of Berberis aristata bark were used for the study. The study involved the antimicrobial (minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) by micro dilution) and antidiarrheal (castor oil induced diarrhea, charcoal motility) tests. The active principle, berberine was characterized by different spectroscopic and chromatographic techniques. RESULTS: The MIC and MBC (of both extracts) against all strains of Shigella were recorded between 125 to 500 µg/mL and 300 to 600 µg/mL, respectively. The MIC and MBC values of berberine are almost comparable to standard ciprofloxacin. UV and IR spectroscopy along with HPTLC and HPLC studies showed presence of berberine in the extracts. The onset of castor oil induced diarrhea was delayed and number of diarrheal episodes was reduced by both the extracts in a dose dependent manner. Similarly, the length of intestine traveled by the feed was also significantly reduced in the charcoal motility test by both the extracts. LD(50) of >5000 mg/kg body weight was observed for both extracts in the acute oral toxicity studies with Swiss albino mice. CONCLUSION: The results validate in vivo and in vitro antidiarrheal activity of Berberis aristata extracts and provide its chemical fingerprint.

An Investigative Review for Pharmaceutical Analysis of 1,4-Dihydropyridine-3,5-Dicarboxylic Acid Derivative: Cilnidipine.

Hypertension is commonly a quiet condition, and it expands the risk of heart diseases and stroke. Calcium delivers a substantial role in cardiovascular functions and hence is essential for cardiac automaticity and functioning. Calcium channel antagonists are the choice of drugs for the management of cardiovascular diseases; they precisely stop the introduction of calcium through L-type calcium channels are existing channels in the heart. Cilnidipine belongs to the class 4th generation calcium channel blockers as a foremost therapeutic agent used in the treatment of hypertension and heart diseases. This review article focuses on an inclusive account of crucial analytical methodologies used for the pharmaceutical analysis of cilnidipine in pure forms, biological samples and pharmaceuticals. According to literature reports several analytical techniques such as hyphenated techniques, high-performance thin-layer chromatography, high-performance liquid-chromatography, capillary electrophoresis, voltammetry, UV/Vis-spectrophotometry, and Fourier-transform infrared spectroscopy approaches have been used for determination of cilnidipine alone or in the combined dosage form. We have also discussed the pharmacopeial assay methods, physicochemical properties, and also depict the stacked column chart for year wise publication count for cilnidipine. From literature, concluded that the high-performance liquid-chromatography and UV/Vis-spectrophotometry methods are the most prevailing methods for the analysis of cilnidipine. The data presented in this review may provide a very significant base for further studies on cilnidipine in the area of drug analysis.

Hydrotropic Solubilization in Pharmaceutical Analysis: Origin, Evolution, Cumulative Trend and Precise Applications.

The hydrotropy though existing as precisely used scientific approach assisting solubilization for all. It took 66 long years to use the concept in drug analysis since its inception in 1916 and first use for facilitation of drug solubility toward better pharmaceutical analysis in 1982. Considering the unending importance in pharmaceutical sciences and thereby in analysis, it's a necessity to comprehensively outlook the origin, evolution, cumulative trend and precise applications in pharmaceutical analysis. Achieved hereby with chronological and comparative assessment of the studies published pertaining to solubility enhancement of poorly soluble drugs with use of hydrotropic agents alone or in combination for assisting pharmaceutical analysis. The thorough literature searches resulted into 77 references over a span of about 38 years. This comprehensive review critically evaluates existing literature; to our surprise we found Ibuprofen sodium, Lignocaine, Niacinamide and Metformin HCl as atypical hydrotropic agents. We also compared herein mono and mixed approaches which indicated prevalence of mono - hydrotropy over mixed. The possible mechanisms behind solubilization are presented for an additional insight. An essential effort has been made to state arbitrary classification to assist in future applications. The obvious purpose of this study was to collectively evaluate the crucial role of hydrotropic agents in pharmaceutical analyses for better drug delivery. This comprehensive review covers all details since inception to the updates till date which will definitely act as appropriate guideline for pharmaceutical analyst's in need of hydrotropy to assist pharmaceutical analysis for therapies today and tomorrow.

GluN2B/N-methyl-D-aspartate Receptor Antagonists: Advances in Design, Synthesis, and Pharmacological Evaluation Studies.

Selective GluN2B/N-methyl-D-aspartate receptor (NMDAR) antagonists have exposed their clinical effectiveness in a cluster of neurodegenerative diseases, such as epilepsy, Alzheimer's disease, Parkinson's disease, pain, and depression. Hence, GluN2B/NMDARs are considered to be a prospective target for the management of neurodegenerative diseases. Here, we have discussed the current results and significance of subunit selective GluN2B/NMDAR antagonists to pave the way for the establishment of new, safe, and economical drug candidates in the near future. By using summarized data of selective GluN2B/NMDAR antagonists, medicinal chemists are certainly a step closer to the goal of improving the therapeutic and side effect profile of selective antagonists. Outlined summary of designing strategies, synthetic schemes, and pharmacological evaluation studies reinvigorate efforts to identify, modify, and synthesize novel GluN2B/NMDAR antagonists for treating neurodegenerative diseases.

Pharmaceutical Analytical Profile for Novel SGL-2 Inhibitor: Dapagliflozin.

Dapagliflozin (DPG) is a novel drug from class of sodium glucose co-transporter 2 (SGL-2) inhibitors which has been evolved as profound treatment option for the type-2diabetes mellitus (T2DM). Considering the severity of the disease the drug is of crucial significance for the therapy and associated research. As a pharmaceutical dosage form DPG has immense importance as an individual drug and with other antidiabetic drugs as combinations. The drugs existing in combination with DPG are Metformin (MET) and Saxagliptin (SXG). The existence of the Dapagliflozin in combinations further created more interest in reviewing its pharmaceutical, analytical and bio-analytical profile. Such estimations are always in need of precise pharmacological and physicochemical information; hence authors have presented it beforehand. Authors hereby wish to present an essential update pertaining to emergence of gliflozins and DPG. The article further presents a simultaneous and comparative assessment of the analytical investigations published in literature for pharmaceutical estimation to assist future analysis. The thorough literature searches revealed fifty three research papers in total till date. A comprehensive presentation of typical; hyphenated and unique methods used for analysis are outlined effectively. The percentile utilization of analytical approaches since appearance of first publication in 2010 is investigated to report trend in determination. The present review explores the pharmaceutical estimation of DPG to scientifically potentiate analytical research and therapeutic future of DPG as a novel SGL-2 Inhibitor antidiabetic.

Development and validation of a reversed-phase high-performance thin-layer chromatography-densitometric method for determination of atorvastatin calcium in bulk drug and tablets.

Atorvastatin calcium is a synthetic HMG-CoA reductase inhibitor that is used as a cholesterol-lowering agent. A simple, sensitive, selective, and precise RP-HPTLC-densitometric determination of atorvastatin calcium both as bulk drug and from pharmaceutical formulation was developed and validated according to International Conference on Harmonization guidelines. The method used aluminum sheets precoated with silica gel 60 RP18F254S as the stationary phase, and the mobile phase consisted of methanol-water (3.5 + 1.5, v/v). The system gave a compact band for atorvastatin calcium with an Rf value of 0.62 +/- 0.02. Densitometric quantification was carried out at 246 nm. The linear regression analysis data for the calibration plots showed a good linear relationship with r = 0.9992 in the working concentration range of 100-800 ng/band. The method was validated for precision, accuracy, ruggedness, robustness, specificity, recovery, LOD, and LOQ. The LOD and LOQ were 6 and 18 ng, respectively. The drug underwent hydrolysis when subjected to acidic conditions and was found to be stable under alkali, oxidation, dry heat, and photodegradation conditions. Statistical analysis proved that the developed RP-HPTLC-densitometry method is reproducible and selective and that it can be applied for identification and quantitative determination of atorvastatin calcium in bulk drug and tablet formulation.

Determination of Iron Chelating Agents by Analytical Methods: A Review.

Acute iron poisoning and chronic iron overload consequences in significant morbidity and mortality worldwide. Treatment of acute iron poisoning and chronic iron overload can be challenging and care providers are often tackled with management dilemmas. Iron chelating agents are commonly prescribed for patients with iron deficiency anemia. In this review article, different analytical techniques are reported used for qualitative and quantitative analysis of iron chelating agents like, deferiprone, deferoxamine, and deferasirox. Efforts are taken to collect all related articles published till October 2018. This review discusses all analytical methods, its advantages and disadvantages as well as its applications. This article will help you to know about basic analytical techniques as well as advanced hyphenated techniques practiced for determination of iron chelating agents in different matrices. The techniques discussed in this review follow the ICH guidelines for method validation.

Pharmaceutical analysis combined with in-silico therapeutic and toxicological profiling on zileuton and its impurities to assist in modern drug discovery.

The obligatory testing of drug molecules and their impurities to protect users against toxic compounds seems to provide interesting opportunities for new drug discovery. Impurities, which proved to be non-toxic, may be explored for their own therapeutic potential and thus be a part of future drug discovery. The essential role of pharmaceutical analysis can thus be extended to achieve this purpose. The present study examined these objectives by characterizing the major degradation products of zileuton (ZLT), a 5-lipoxygenase (5-LOX) inhibitor being prevalently used to treat asthma. The drug sample was exposed to forced degradation and found susceptible to hydrolysis and oxidative stress. The obtained Forced Degradation Products (FDP's) were resolved using an earlier developed and validated Ultra-High-Pressure Liquid Chromatography Photo-Diode-Array (UHPLC-PDA) protocol. ZLT, along with acid-and alkali-stressed samples, were subjected to Liquid-chromatography Mass-spectrometry Quadrupole Time-of-flight (LC/MS-QTOF) studies. Major degradation products were isolated using Preparative TLC and characterized using Q-TOF and/or Proton nuclear magnetic resonance (1HNMR) studies. The information obtained was assembled for structural conformation. Toxicity Prediction using Komputer Assisted Technology (TOPKAT) toxicity analyses indicated some FDP's as non-toxic when compared to ZLT. Hence, these non-toxic impurities may have bio-affinity and can be explored to interact with other therapeutic targets, to assist in drug discovery. The drug molecule and the characterized FDP's were subjected to 3-Dimensional Extra Precision (3D-XP)-molecular docking to explore changes in bio-affinity for the 5-LOX enzyme (PDB Id: 3V99). One FDP was found to have a higher binding affinity than the drug itself, indicating it may be a suitable antiasthmatic. The possibility of being active at other sites cannot be neglected and this is evaluated to a reasonable extent by Prediction of Activity Spectra for Substances (PASS). Besides being antiasthmatic, some FDP's were predicted antineoplastic, antiallergic and inhibitors of Complement Factor-D.

Application of UV-spectrophotometric methods for estimation of tenofovir disoproxil fumarate in tablets.

Two new, simple and cost effective UV-spectrophotometric and first order derivative methods were developed for estimation of tenofovir disoproxil fumarate in bulk and tablets. Tenofovir disoproxil fumarate was estimated at 260 nm in 0.1N HCl. In first order derivative, it showed amplitude at 273 nm. In both the methods linearity was found to be in the range of 5-40 micro/ ml; for UV-spectrophotometric method (Y=0.02586 x +0.0083; r(2)=0.9999) and for first order derivative spectrophotometric method (Y=0.00132 x +0.00035; r(2)=0.9995), respectively. These methods were tested and validated for various parameters according to USP guidelines. The quantitation limits were found to be 1.546 and 1.986 micro/ ml, for both the methods. The proposed methods were successfully applied for the determination of tenofovir disoproxil fumarate in pharmaceutical formulations. The results demonstrated that the procedure is accurate, precise and reproducible (relative standard deviation <2%), while being simple, cheap and less time consuming and can be suitably applied for the estimation of tenofovir disoproxil fumarate in different dosage forms.