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Validated stability-indicating HPTLC method for cefixime and azithromycin with preparative isolation, identification, and characterization of degradation products

Gawande V. T., Bothara K. G., Satija C. O.

Acta Chromatographica

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2018

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Vol. 30, no. 4

212--218

EN

Stability-indicating High-Performance Thin-Layer Chromatography (HPTLC) method for simultaneous estimation of cefixime trihydrate and azithromycin dihydrate was developed. Both the drugs were subjected to different stress conditions recommended by International Conference on Harmonization (ICH) guideline Q1A (R2). Forced degradation was carried out for hydrolytic, oxidative, photolytic, and thermal degradation conditions. Cefixime was susceptible for degradation under all stress conditions showing four degradation products (CI–IV). However, azithromycin formed only one degradation product (AI) under acid hydrolysis. Aluminum plates precoated with silica gel 60F254 were used as the stationary phase while mixture of ethyl acetate–methanol–acetone–toluene–ammonia (1:5:7:0.5:0.5, v/v) was used as mobile phase. Detection wavelength used was 235 nm for CEFI and CI–IV. AZI and AI were detected by post development derivatization, spraying with sulfuric acid–ethanol (1:4, v/v) followed by heating at 100 °C for 5 min. Degradation products were isolated by preparative HPTLC and characterized by MS/MS. The developed method was validated for linearity, precision, accuracy, specificity, and robustness and has been successfully applied in the analysis of these drugs in tablet dosage form.

2

Stability-indicating HPLC method for simultaneous determination of degradation products and process-related impurities of avanafil in avanafil tablets

Kumar N., Sangeetha D., Kalyanraman L., Sainath K.

Acta Chromatographica

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2018

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Vol. 30, no. 3

158--163

EN

The objective of the current research is to understand the degradation behavior of avanafil under different stress conditions and to develop a stability-indicating high-performance liquid chromatography (HPLC) method for simultaneous determination of degradants observed during degradation. Avanafil tablets were exposed to acid, base, water, oxidative, thermal, and photolytic degradation conditions. In acid, oxidative, thermal, and humidity degradation, significant degradation was observed. All the degradants observed during degradation were separated from known impurities of avanafil by using reverse-phase (RP)-HPLC. Mobile phase A, 0.1% trifluoro acetic acid and triethylamine in water, and mobile phase B, water and acetonitrile in the ratio of 20:80 (v/v), were used at a flow rate of 1.2 mL/min in gradient elution mode. Separation was achieved by using Inertsil ODS 3 column (3 μm, 4.6 mm × 250 mm) at 45 °C. Peak responses were recorded at 245 nm. Method capability for detecting and quantifying the degradants, which can form during stability, was proved by demonstrating the peak purity of avanafil peak in all the stressed samples. Mass balance was established by performing the assay of stressed sample against reference standard. Mass balance was found >97% for all the stress conditions. The developed analytical method was validated as per International Conference on Harmonization (ICH) guidelines. The method was found specific, linear, accurate, precise, rugged, and robust.

3

Stability-indicating HPLC-DAD method development, validation, and stress degradation studies for triamterene and xipamide in their combined tablet dosage form

El-Kimary E. I.

Acta Chromatographica

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2016

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Vol. 28, no. 1

79--98

EN

A simple stability-indicating high-performance liquid chromatography-diode array detection (HPLC-DAD) method has been developed for the simultaneous determination of triamterene (TRI) and xipamide (XIP) in presence of the degradation products generated in studies of forced decomposition. Drugs were subjected to stress by hydrolysis (acidic, alkaline, and neutral), oxidation, photolysis (254 and 365 nm), and dry and wet heat treatments. Degradation occurs under acidic and alkaline conditions (TRI only), oxidative stress (TRI and XIP), and by photolysis (XIP only), but both drugs were stable under other stress conditions investigated. Separation of the two drugs from all the degradant peaks was achieved within 11 min using C8 column (250 × 4.6 mm, 5 μm) and mobile phase consisting of acetonitrile and 0.05 M phosphate buffer adjusted to pH 4 delivered at a flow rate of 1 mL min -1 using gradient elution system. The drugs were quantified at 220 nm using photodiode array detector, based on peak area. Peak homogeneity of the two drugs was checked using diode array detector, and the purity angle was within the purity threshold limit in all of the stressed samples. The calibration graphs for each drug were rectilinear in the range of 0.2–50 and 0.1–20 μg Ml -1 for TRI and XIP, respectively. The method was validated in compliance with International Conference on Harmonization (ICH) guidelines; in terms of linearity, accuracy, precision, robustness, limit of detection, and limit of quantitation. The proposed method was successfully applied for the determination of the investigated drugs in their tablet without interference from excipients with acceptable accuracy and precision; the label claim percentages were 100.23 ± 0.70% and 100.75 ± 1.11% for TRI and XIP, respectively.

4

Stress degradation studies on zolpidem tartrate using LC-DAD and LC-MS methods

Malesevic M., Zivanovic L., Protic A., Radisic M., Lausevic M., Jovic Z., Zecevic M.

Acta Chromatographica

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2014

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Vol. 26, no. 1

81--96

EN

The present study was designed to characterize the possible degradation products of zolpidem tartrate under various stress conditions according to International Conference on Harmonization (ICH) guidelines Q1A(R2). After exposure to light, heat, hydrolysis, and oxidation, the drug significantly degraded under photolytic and acid/base hydrolytic conditions. Degradation resulted in the formation of four key degradants. Degradation products were resolved from each other and the drug by employing an isocratic elution method on Luna C18 column with mobile phase consisting of methanol-10 mM ammonium acetate (68.4:31.6, v/v), wherein pH was adjusted to 5.4 with glacial acetic acid. To characterize the degradation products, a method was extended to LC-MS and a mass fragmentation pattern was established using single quadrupole. The degradants were identified as zolpacid, oxozolpidem, zolpaldehyde, and zolpyridine. Finally, the most possible degradation mechanism of zolpidem tartrate in different environments was proposed.

5

Biocompatibility of L-lactide-co-glycolide-co-trimethylene-carbonate shape memory terpolymer with human chondrocytes

Kłosek R., Komacki J., Orchel A., Jelonek K., Dobrzyński P., Kasperczyk J., Dzierżewicz Z.

Engineering of Biomaterials

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2012

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Vol. 15, no. 113

23--25

EN

Biomedical application of biodegradable shape memory terpolymers obtained from L-lactide, glycolide, trimethylene carbonate (TMC) have been intensively investigated in recent years. All applicable biomedical materials must be biocompatible, which means that they cannot cause toxic, cytotoxic, allergic, or carcinogenic reactions. The first study evaluating the biocompatibility of the material is determination of its cytotoxicity. The purpose of this study was to assess the biocompatibility of poly(L-lactide-co-glycolide-co-trimethylene-carbonate) 75:13:12, synthesized using Zr(Acac)4 as an initiator of polymerization. The terpolymer was degraded for 30, 60 and 90 days at 37§C in water. The effect of degradation products on the growth of human articular chondrocytes was determined using the sulforhodamine B assay. The examined terpolymer was characterized by means of NMR spectroscopy, GPC and DSC. The results showed that the studied terpolymer was biocompatible with tested cells.

6

Degradacja enzymatyczna poliuretanów. Cz. I. Produkty rozkładu i modelowanie procesu

Wojturska J.

Polimery

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2011

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T. 56, nr 2

91-98

PL

Publikacja obejmuje informacje wstępne dotyczące czynników wpływających na hydrolizę enzymatyczną polimerów i mechanizm ich degradacji oraz przegląd literatury dotyczącej enzymatycznej degradacji poliuretanów (PUR). Przedstawiono w niej opis badań obejmujących wyodrębnianie i identyfikację produktów degradacji PUR uwalnianych wskutek działania enzymu oraz doniesienia literaturowe odnoszące się do matematycznego ujęcia procesów degradacji. Stworzenie takiego modelu degradacji enzymatycznej PUR in-vitro, jest niezbędne zarówno do zrozumienia kinetyki enzymatycznego rozkładu, jak i do ewentualnego przewidzenia zachowania się polimerów in-vivo

EN

This paper constitutes a presentation of the factors influencing the enzymatic hydrolysis of polymers, the corresponding degradation mechanism and also a review of the literature regarding enzymatic degradation of polyurethanes (PUR) in general. Studies on the separation and identification of PUR degradation products released as a result of enzyme activity have been presented. Moreover, the literature regarding the mathematical aspects of degradation process was reviewed. The development of such a model for the in vitro enzymatic degradation of PUR is essential in understanding the kinetics of the process and enable the prediction of polymer behavior in vivo.