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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.
EN
In this reported study, a direct high-performance thin-layer chromatographic (HPTLC) method was developed to qualitatively detect and quantitatively determine glycerol in Antarctic krill for the first time. This procedure was based on the extraction of glycerol by ultrasonic solvent extraction with anhydrous ethanol, silica-gel column chromatographic separation, HPTLC detection and quantification using methylene chloride–methanol (5:1, v/v) as the developing solvent and alkaline potassium permanganate as chromogenic agent. The content of glycerol was 1.3725 ± 0.218 mg/g in freeze-dried Antarctic krill. The structure of glycerol in the Antarctic krill was subsequently determined by gas chromatography–mass spectrometry (GC–MS) which verified the presence of the material in the krill. The HPTLC method exhibited excellent accuracy with a recovery of 90.1–103.3% and good precision with a relative standard deviation (RSD) of 1.59–4.84%. The results clearly exhibited the applicability of the proposed for quantifying glycerol in Antarctic krill.
EN
The main hurdle for the estimation of the purity of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) is its insolubility in most of the known organic solvents. In the conventional method, TATB is digested with steam in a modified Kjeldahl digester and the ammonia evolved is estimated quantitatively. To do away with this cumbersome method, a simple, rapid HPLC technique using a reverse phase C-18 column has been established for quantitative determination of the purity of TATB. A sharp and symmetrical peak with a retention time of 2.92 min at 355 nm is obtained for pure TATB when the flow rate is 2.0 mL/min. The linearity of the detector response has been studied with sample concentrations ranging from 10 to 50 mg/L. The method addresses two important issues of sample preparation and the precision of measurement. Unlike the previously reported HPLC techniques which mainly aimed at the detection of TATB, the present work is a validated account of a quantitative estimation of purity. Regular production batch samples have been assayed by this method and the results are compared with those obtained from the conventional analysis. The HPLC method is convenient and reliable for quality control of the product at the plant level.
EN
Two simple, accurate, specific, and precise chromatographic methods, reversed phase high-performance liquid chromatography (RP-HPLC) and highperformance thin-layer chromatography (HPTLC), have been developed and validated for the determination of moxifloxacin hydrochloride and difluprednate in ophthalmic dosage form according to International Conference on Harmonization (ICH) guidelines. The separation of moxifloxacin hydrochloride and difluprednate in HPLC was performed on reverse phase (C18, 5 μm, 250 × 4.6 mm) column using isocratic condition, with acetonitrile, 5 mM disodium hydrogen phosphate buffer adjusted to pH 5, and methanol (50:25:25, v/v/v) as mobile phase. The flow rate for analysis was 1.0 mL min−1, and the selected chromatographic conditions effectively separated moxifloxacin hydrochloride and difluprednate with retention time of 3.6 and 6.6 min, respectively, at a detection wavelength of 254 nm. Chromatographic development in HPTLC was performed on precoated silica gel 60F254 aluminium plates with n-hexane, 6 M ammonia, and acetone (5:1.8:2, v/v/v) as mobile phase. The detection wavelength for simultaneous estimation of both drugs was 232 nm in HPTLC, and the Rf values for moxifloxacin hydrochloride and difluprednate were 2.2 and 7.1, respectively. The linear concentration range for HPLC method was 5 to 50 μg Ml-1 and 1 to 10 μg Ml-1; and for HPTLC method was 1200 to 2200 ng band-1 and 200 to 1200 ng band-1 for moxifloxacin hydrochloride and difluprednate, respectively. Moreover, Bartlett's test applied on the calibration peak areas revealed homoscedasticity of variance for both the methods. Both methods were validated with respect to system suitability, specificity, linearity, precision, accuracy, and robustness. The mean percentage recoveries for marketed formulation in terms of accuracy were found to be 100.53 and 100.58 for HPLC; and 100.56 and 100.30 for HPTLC for moxifloxacin hydrochloride and difluprednate, respectively. The pooled percent relative standard deviation (% RSD) value for repeatability, intermediate precision, accuracy, and robustness studies for both the methods were found to be less than 2. Result of paired t-test at 95% confidence level reveals that there is no significant difference between recoveries of drugs, using both methods. The results of the developed chromatographic methods were acceptable assuring that these methods can be successfully applied for routine quality control testing of both bulk and ophthalmic dosage forms, without any interference from the excipients.
EN
A simple, selective, precise, and stability-indicating high-performance thinlayer chromatographic method for analysis of sitagliptin phosphate both in a bulk and in pharmaceutical formulation has been developed and validated. The method employed high-performance thin-layer chromatography (HPTLC) aluminium plates precoated with silica gel 60 RP-18 F254 as the stationary phase. The solvent system consisted of methanol-water-triethylamine (8:2:0.05 v/v). The system was found to give compact spot for sitagliptin phosphate (Rf value of 0.55 ± 0.03). Densitometric analysis of sitagliptin phosphate was carried out in the absorbance mode at 267 nm. The linear regression analysis data for the calibration plots showed good linear relationship with r2 = 0.998±0.0015 with respect to peak area in the concentration range 1000–6000 ng per spot. The mean value ± SD of slope and intercept was 0.723 ± 0.043 and 17.24 ± 18.78 with respect to peak area. The method was validated for precision, recovery, and robustness. The limits of detection and quantification were 85.80 and 265.42 ng per spot, respectively. Sitagliptin phosphate was subjected to acid and alkali hydrolysis, oxidation, and photo and thermal degradation. The drug undergoes degradation under acidic, basic, and oxidative conditions. This indicates that the drug is susceptible to acid and base, and oxidation. The degraded product was well resolved from the pure drug with significantly different RF value. Statistical analysis proves that the method is repeatable, selective, and accurate for the estimation of investigated drug. The proposed developed HPTLC method can be applied for identification and quantitative determination of sitagliptin phosphate in bulk drug and pharmaceutical formulation.
6
Content available remote Determination of some psychotropic drugs in human plasma by HPTLC
EN
Psychotropic drugs: desipramine, olanzapine and mitrazapine were chromatographed on cyanopropyl-silica and Diol-silica thin layers using various nonaqueous and aqueous eluents.The best results were obtained with addition of ammonia to nonaqueous eluent on both adsorbents. On the basis of the optimization, systems for extraction from human plasma and quantitative determination of investigated drugs were selected.RP18 encaped SPE columns conditioned and pre-eluted with acetonitrile:water:ammonium buffer at pH 8.6 (5:5:2) and eluted with methanol:water (9:1) containing 2% acetic acid were used for sample preparation with high recoveries of all investigated drugs. Diol and CN plates with mixture of 15% methanol in diisopropyl ether + 1% ammonia were used for quantitative analysis by a calibration curve method.
EN
Eladi Gutika is a polyherbal formulation official in “Ayurvedic formulary of India” and used for dry cough and throat infection. A simple, specific and precise high-performance thin-layer chromatography (HPTLC) method has been developed for quantification of piperine and 18-β glycyrrhetinic acid in Eladi Gutika. We report the extraction and estimation of these compounds in a laboratory prepared sample of Eladi Gutika and two of its marketed formulations. The compounds were chromatographed on precoated silica gel G 60254 plates in the mobile phase comprising of toluene, ethyl acetate, and glacial acetic acid. Under the optimized chromatographic conditions, the calibration plot was found to be linear in the range of 0.2–1 g mL-1 with a correlation coefficient R2 = 0.9902 for piperine and 0.9904 for 18-β glycyrrhetinic acid. Mean recovery for piperine was 99.75% w/w and for 18-β glycyrrhetinic acid was 101.36% w/w.
EN
Gymnemic acid (GA), a well known anti-diabetic compound has been detected in methanol extracts of intact leaves and in vitro callus cultures derived from leaf explants of Gymnema sylvestre. Callus biomass was developed in MS medium with optimum plant growth regulators (OPGRs) of 2,4-D (1.5 mg L-1) + KN (0.5 mg L-1) under abiotic stress conditions at 45 days determined by growth curve analysis. GA detection and quantification were carried out using thin-layer chromatography (TLC), highperformance thin-layer chromatography (HPTLC), high-performance liquid chromatography (HPLC), and gravimetric techniques. GA detection peak area and their absorption spectra were evaluated through HPTLC and HPLC with the standard GA. Quantification of GA had showed the linearity, accuracy, robustness and precision by HPLC. GA content was significantly higher in gravimetric method than HPLC. All these methods were found to be simple, accurate, selective and rapid and could be successfully applied for the determination of GA. It could have potential as a pharmaceutical drug for Type 1 diabetes mellitus (IDDM) and obesity.
EN
A simple, selective, precise, and stability-indicating high-performance thin-layer chromatographic method for analysis of repaglinide both in a bulk and in pharmaceutical formulation has been developed and validated. The method employed high-performance thin-layer chromatography (HPTLC) aluminum plates precoated with silica gel 60 RP-18 F254 as the stationary phase. The solvent system consisted of chloroform-methanol-ammonia (4.5:0.8:0.05, v/v). The system was found to give compact spot for repaglinide (RF value of 0.55 ± 0.03). Densitometric analysis of repaglinide was carried out in the absorbance mode at 288 nm. The linear regression analysis data for the calibration plots showed good linear relationship with r2 = 0.998 ± 0.0015 with respect to peak area in the concentration range 600–1600 ng per spot. The mean value ± SD of slope and intercept were 3.38 ± 1.47 and 986.9 ± 108.78, with respect to peak area. The method was validated for precision, recovery, and robustness. The limits of detection and quantification were 22.64 and 68.84 ng per spot, respectively. Repaglinide was subjected to acid and alkali hydrolysis, oxidation, and thermal degradation. The drug undergoes degradation under acidic and basic conditions. This indicates that the drug is susceptible to acid and base. The degraded product was well resolved from the pure drug with significantly different RF value. Statistical analysis proves that the method is repeatable, selective, and accurate for the estimation of investigated drug. The proposed developed HPTLC method can be applied for identification and quantitative determination of repaglinide in bulk drug and pharmaceutical formulation.
EN
Gymnemic acid (GA) is one of the phytoconstituents present in Gymnema sylvestre. Estimation of GA was carried out first time from microencapsulated polyherbal formulation. Microencapsulated polyherbal formulations (F1 and F2) contain various plant extracts; hence, proper resolution of GA peak in high-performance thin-layer liquid chromatography (HPTLC) analysis of F1 and F2 is the problem. Hence, HPTLC analysis method for F1 and F2 is developed and validated for quantitative determination of GA. HPTLC analysis of F1 and F2 was carried out using TLC aluminum plates precoated with silica gel 60F254 eluted with chloroform-methanol-water (6.5 mL + 4.5 mL + 1.0 mL), and densitometric analysis was carried out at 580 nm. Complete validation was performed using standard methods. This HPTLC method was found to be reproducible, accurate, and can detect GA at microgram level. The new optimized mobile phase gave good resolution of GA peak for its proper quantification in microencapsulated polyherbal formulation.
EN
Methods based on RP-HPLC and HPTLC with UV detection for rapid quantitative determination of marker component in Enicostemma hyssopifolium, swertisin are described. The recovery of the compound was between 96.3–101.5% by HPTLC method and 98.9–100.2% by HPLC assay. The relative standard deviations ranged between 1.53–1.81 (intra-day) and 1.33–1.96 (inter-day) for HPTLC and 0.60–1.11 (intra-day) and 0.80–1.20 (inter-day) for HPLC. The methods were used for routine analysis of swertisin in the aerial parts of the plant. HPTLC method was found to be more economic and less time consuming than HPLC. Reproducibility and recovery in HPLC method were better than that in HPTLC method.
EN
Mangroves are the source of several bioactive secondary metabolites and have proven activity against human, animal and plant pathogens. Rhizophora mucronata is a mangrove species belonging to the family Rhizophoraceae. Betulin and lupeol are two naturally occurring pentacyclic triterpenoids having excellent biological properties. Chloroform extract of R. mucronata, collected from Pitchavaram, Muthupett and Manakudy regions of Tamilnadu, was chromatographed on silica gel 60F254 plates with nhexane and ethyl acetate (80:20) (v/v) as the mobile phase. Derivatizations were done using anisaldehyde and sulfuric acid reagents. The triterpenoids such as betulin and lupeol were identified through HPTLC method. This is the first report for the thin layer chromatographic (TLC) identification of triterpenoids such as betulin and lupeol from R. mucronata, which will be the most valuable information to identify the antimalarial and antiviral activities.
EN
Transfer of four rapid thin-layer chromatography (TLC) screening methods used to detect substandard and counterfeit pharmaceutical products to quantitative high-performance TLC (HPTLC)-densitometry methods is demonstrated. These methods for acetaminophen, acetylsalicylic acid, ibuprofen, and chlorpheniramine maleate are contained in a Compendium of methods developed by Kenyon and Layloff for use in countries with limited resources. The new quantitative methods use Merck HPTLC silica gel 60 F254 glass plates, automated standard and sample application, and automated densitometry for detection, identification, and quantification. Standard and sample solution preparation and application procedures for obtaining calibration curves and bracketed samples are described. The HPTLC plates give better efficiency, selectivity, and resolution than TLC, and the new methods overcome the deficiencies in technology related to manual application and visual zone comparison that do not allow the Compendium TLC procedures to support regulatory compliance actions. These transferred methods can be fully validated according to International Conference on Harmonization (ICH) guidelines or by interlaboratory studies if their applications require. The approach described can be used to transfer the remaining Compendium methods as well as the GPHF [Global (formerly German) Pharma Health Fund E.V.] Minilab kit TLC screening methods.
EN
We present a video-densitometric quantification method for the triazine herbicides atraton, terbumeton, simazine, atrazine and terbutylazine. Triazine herbicides were separated on silica gel using methyl-t-butyl ether, cyclohexane (1+1, v/v) as mobile phase. The quantification was based on a bioeffective-linked analysis using chloroplast and 2,6-dichlorophenolindophenol. Within 1-2 minutes HILL-reaction inhibitor substances show blue-grey zones on a pale yellowgreen background. To increase the contrast, the moist plate can be dipped into a solution of PEG-600 (10% PEG-600 in methanol) for 2s. Measurements were carried out using a 16 bit ST-1603ME CCD camera with 1.56 megapixels (from Santa Barbara Instrument Group, Inc., Santa Barbara, USA). A white LED was used for illumination purposes. The range of linearity covers more than one magnitude using the (1/R) - 1 expression data transformation. The method can be used for herbicide screenings in environmental samples, because not spectral sensitivity but herbicide activity is measured. The separation method is cheap, fast and reliable.
EN
Seven different thin-layer chromatography stationary phases, one additional stationary layer pretreatment, eight mobile phases, two spotting techniques, and three detection reagents were evaluated for the determination of glucose in mouse fecal samples. Quantitative analysis was performed by slit-scanning densitometry. The optimal system was found to be Merck silica gel HPTLC plates with a concentrating zone developed with 1-butanol-glacial acetic acid-diethyl ether-deionized water 27:18:5:3. α-Naphthol-sulphuric acid detection reagent was found to give the best quantitative results, while the naphthoresorcinol reagent was the most useful for qualitative analysis. Semiautomatic application of samples with a CAMAG Linomat was found to give more compact bands and better separations than manual application. Using this system, quantification of glucose was achieved in mouse fecal samples. The amounts of glucose in the fecal samples of BALB/c mice infected with the intestinal trematode E. caproni were compared to control samples of uninfected mice. On the third and tenth days of postinfection, it was determined that the amount of glucose in the infected fecal samples was significantly greater than in the control samples. This indicates that metabolic profiling of glucose using TLC is possible in the mouse model and that TLC may potentially be used to test for the presence of E. caproni in humans.
16
EN
A simple, selective, precise, and stability-indicating high-performance thin layer chromatographic (HPTLC) method has been established and validated for the analysis of idebenone in bulk drug and formulations. The compounds were analyzed on aluminum-backed silica gel 60 F254 plates with petroleum ether-methanol (4:1, υ/υ) as mobile phase. Densitometric analysis of idebenone was performed at 282 nm. Regression analysis data for the calibration plots were indicative of good linear relationship between response and concentration over the range of 200–600 ng per spot. The correlation coefficient (r2) was 0.989 ± 0.002. The values of slope and intercept of the calibration plots were 2.386 ± 0.0435 and 577.733 ± 19.545, respectively. The method was validated for precision, accuracy, robustness, and ruggedness. The limits of detection and quantification were 14.642 and 44.369 ng, respectively. Idebenone was subjected to acid, base, peroxide, and sunlight degradation. In stability tests, the drug was susceptible to acid and basic hydrolysis, oxidation, and photodegradation.
EN
A simple and fast high-performance thin-layer chromatographic method has been developed for the simultaneous determination of ampicillin and amoxicillin. Titanium(IV) silicate (a synthetic inorganic ion-exchanger)-coated thin-layer chromatography (TLC) plates were used to separate them, employing a mixture of K2HPO4 (0.1 M) + KH2PO4 (0.1 M), 1:1 (υ/υ), as mobile phase. The development time was 18 min. The plates were sprayed with fresh 1% solution of ninhydrin in ethanol. The developed method enables highly contrasted chromatograms with red purple spots in white background. Densitometric measurements were made at wavelength 546 nm using Camag TLC Scanner-3. The ampicillin and amoxicillin recovery of the total procedure were equal to 99.99 and 100.43, respectively. The procedure is quantitatively characterized. Linearities were r2 > 0.9958 and 0.9954 for ampicillin and amoxicillin, respectively, and the relative standard deviations were <0.89 and 0.61, respectively. The limits of detection were 2.9 and 1.5 ng per spot and the limits of quantification were 14.5 and 7.5 ng per spot, respectively. The method is rapid, selective, precise, and accurate and thus can be used for the routine analysis of pharmaceutical preparations in quality control laboratories of the pharmaceutical industry. The method is successfully applied for the determination of ampicillin and amoxicillin in human blood plasma and urine.
EN
In this research paper we describe validated high-performance liquid chromatographic (HPLC) and high-performance thin-layer chromatographic (HPTLC) methods for simultaneous analysis of tamsulosin hydrochloride and dutasteride in tablet formulations. HPLC was performed on a C 18 column with 85:15 ( υ/υ ) methanol-0.02 M ammonium acetate buffer (pH 9.5, adjusted with triethylamine) as mobile phase. HPTLC was performed on aluminium foil-backed silica gel G60F 254 layers with toluene-methanol-triethylamine 9:1.5:1 ( υ/υ/υ ) as mobile phase. In HPLC, quantification was achieved by photo diode-array (PDA) detection at 274 nm over the concentration range 1–20 μg mL -1 for both; mean recovery was 98.18 ± 0.698 and 99.94 ± 0.611% for TAM and DUTA, respectively. In HPTLC, quantification was achieved by UV detection at 280 nm over the concentration range 200–2000 ng per band for both; mean recovery was 99.66 ± 0.892 and 100.05 ± 1.012% for TAM and DUTA, respectively. These methods are simple, precise, and sensitive, and are suitable for simultaneous analysis of TAM and DUTA in tablet formulations.
EN
This paper describes a simple, precise, and accurate HPTLC method for simultaneous quantification of sennoside A, sennoside B, and kaempferol in Cassia fistula whole plant extract. Chromatographic separation of the sample extract was performed on aluminium foil plates coated with silica gel 60 F 254 as stationary phase. The mobile phase was toluene-ethyl acetate-methanol-formic acid 8:10:5:2 ( υ/υ ). Densitometric evaluation of the separated bands was performed at 270 nm. Sennosides A and B and kaempferol were satisfactorily resolved at R F 0.22 ± 0.05, 0.19 ± 0.05, and 0.81 ± 0.05, respectively. Recovery of sennosides A and B and kaempferol from Cassia fistula extract was 98.03, 98.74, and 99.08%, respectively. The method was validated for specificity, accuracy, linearity (100–400 ng per band), and precision (instrument precision in the range 1.03–1.33 and method precision in the range of 1.31–1.75) in accordance with ICH guidelines.
EN
This paper describes a new, simple, precise, and accurate HPTLC method for quantification of (−)-epicatechin in the leaves of Cassia fistula . The leaves were separately extracted with methanol and water by both maceration and hot extraction (Soxhlet apparatus). Chromatographic separation of the drug was performed on aluminium foil silica gel 60 F 254 plates with toluene-ethyl acetate-formic acid-methanol 20:12:4:4 ( v / v ) as mobile phase. Densitometric evaluation of the separated zone was performed at 280 nm. Epicatechin in the extract was satisfactorily resolved with R F 0.22 ± 0.02. The accuracy and reliability of the method were assessed by evaluation of linearity (200–800 ng per band), precision (method precision RSD 1.42% and instrumental precision RSD 1.12%), accuracy (98.12%), and specificity in accordance with ICH guidelines.
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