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1.
张志敏  方正  李长春 《合成化学》2007,15(5):536-542
综述了降血脂药物匹伐他汀钙的合成方法和最新研究进展。参考文献21篇。  相似文献   

2.
《Analytical letters》2012,45(14):2232-2243
Abstract

This article describes the development and validation of a first derivative UV quantitative analytical method for determination of candesartan cilexetil in tablet dosage forms. A signal at 270.1 nm of the first derivative spectrum (ID270.1) was found adequate for quantification. The limit of quantification was 3.06 µg/ml. The linearity between ID270.1 nm and concentration of candesartan cilexetil in the range of 6.00–32.00 µg/ml presented a correlation coefficient of (r2) = 0.9990. The mean recovery percentage was 100.97 and 99.23% for candesartan cilexetil standard solution and candesartan standard cilexetil solution with excipients, respectively. The intraday and interday accuracy of the assay was 98.60% and 99.10% respectively. The intraday and interday variability was below 2.0%.

The proposed method is accurate, precise, sensitive, and selective and can be used in quality control laboratories for its intended purpose.  相似文献   

3.
《Analytical letters》2012,45(12):1831-1843
Abstract

Methods for determination of oxazepam in pharmaceutical formulation by derivative ultraviolet (UV) spectrophotometry as well as high-performance thin-layer chromatography (HPTLC) UV densitometry were described. For UV-derivative spectrophotometry, some derivatives and wavelengths may be recommended for routine quality control of the drug of interest. On the other hand, HPTLC provided good results, but only when the calibration curve was estimated using nonlinear regression analysis. The HPTLC method was developed with silica F254 plates, a mobile phase of benzene/ethanol (5:1, v/v), and densitometric detection at 204 nm receiving R f  = 0.47. Developed methods were validated and found to be sufficiently precise and reproducible for established conditions.  相似文献   

4.
In the literature, greener analytical approaches for determining thymol in its commercial formulations, plant-based phytopharmaceuticals, and biological fluids are scarce. As a result, the goal of this study is to develop and validate a normal-phase “high-performance thin-layer chromatography (HPTLC)” method for determining thymol in commercial formulations, essential oils, traditional extracts (TE), and ultrasound-based extracts (UBE) of Thymus vulgaris and Origanum vulgare obtained from various geographical regions. The greener mobile phase for thymol analysis was a binary combination of cyclohexane and ethyl acetate (85:15, v/v). The derivatized densitometric analysis of thymol was carried out under visible mode at 530 nm utilizing anisaldehyde-sulfuric acid as a derivatizing/visualizing agent. In the 10–2000 ng/band range, the greener normal-phase HPTLC method was linear. Furthermore, for thymol analysis, the proposed analytical approach was simple, quick, inexpensive, accurate, precise, robust, sensitive, and greener. The thymol contents in commercial formulation were computed as 7.61% w/w. In general, the thymol contents were maximum in essential oils of T. vulgaris and O. vulgare compared to the other sample matrices studied. The thymol contents of TE of T. vulgaris and O. vulgare of different geographical regions were significantly low compared to their UBE extract. Using 12 distinct components of green analytical chemistry, the overall “analytical GREEnness (AGREE)” scale for the proposed analytical approach was computed 0.79, showing the good greener nature of the proposed analytical approach. Overall, the greener normal-phase HPTLC technique was found to be reliable for determining thymol in commercial formulations and plant-based phytopharmaceuticals.  相似文献   

5.
Two sensitive and reproducible methods are described for the quantitative determination of dasatinib in the presence of its degradation products. The first method was based on high performance thin layer chromatography (HPTLC) followed by densitometric measurements of their spots at 280 nm. The separation was on HPTLC aluminium sheets of silica gel 60 F254 using toluene:chloroform (7.0:3.0, v/v). This system was found to give compact spots for dasatinib after development (R F value of 0.23 ± 0.02). The second method was based on high performance liquid chromatography (HPLC) of the drug from its degradation products on reversed phase, PerfectSil column [C18 (5 μm, 25 cm × 4.6 mm, i.d.)] at ambient temperature using mobile phase consisting of methanol:20 mM ammonium acetate with acetic acid (45:55, v/v) pH 3.0 and retention time (t R = 8.23 ± 0.02 min). Both separation methods were validated as per the ICH guidelines. No chromatographic interference from the tablet excipients was found. Dasatinib was subjected to acid–alkali hydrolysis, oxidation, dry heat, wet heat and photo-degradation. The drug was susceptible to acid–alkali hydrolysis and oxidation. The drug was found to be stable in neutral, wet heat, dry heat and photo-degradation conditions. As the proposed analytical methods could effectively separate the drug from its degradation products, they can be employed as stability indicating.  相似文献   

6.
《Analytical letters》2012,45(9):1641-1653
Abstract

High performance thin layer chromatographic (HPTLC) and high performance liquid chromatographic (HPLC) methods were developed for the simultaneous determination of Tinidazole and Furazolidone in suspension.

In the HPTLC method the separation of Tinidazole and Furazolidone was carried out on silica gel 60F254 HPTLC glass plate using chloroform:methanol:ammonia (9:1:0.1 v/v) as a mobile phase. Rf values obtained were 0.63 and 0.79 for Furazolidone and Tinidazole respectively. Densitometric evaluation was done at 335 nm. Linearity was obtained within the concentration range 10–50 μg/ml and 3.5–17.5 μg/ml for Tinidazole and Furazolidone respectively.

The second method is based on high performance liquid chromatography on a reversed phase column (μ Bondapak C18) using a mobile phase comprised of water: acetonitrile: triethylamine (80:20:0.1 v/v) adjusted to pH = 3.0 with dil. phosphoric acid. Retention times were 5.24 and 7.82 min for Tinidazole and Furazolidone respectively at a flow rate of 1.5 ml/min. Detection was done at 335 nm. Linearity was obtained within the concentration range 30–180 μg/ml and 10.5–63 μg/ml for Tinidazole and Furazolidone resp.  相似文献   

7.
An HPTLC method for analysis of Exemestane in bulk and pharmaceutical formulation has been established and validated. The analyte was separated on aluminium plates precoated with silica gel 60 F254. The mobile phase was chloroform:methanol 9.2:0.8 (v/v). Quantification was done by densitometric scanning at 247 nm. Response was a linear function of Exemestane concentration in the range of 100–500 μg mL−1. The limit of detection and quantification for Exemestane were 5.8 and 17.58 μg mL−1, respectively. Average recovery of Exemestane was 100.1, which shows that the method was free from interference from excipients present in the formulation. The established method enabled accurate, precise, and rapid analysis of Exemestane in bulk as well as pharmaceutical formulation.  相似文献   

8.
《Analytical letters》2012,45(11):2409-2420
Abstract

A method for the spectrofluorimetric determination of nafcillin is proposed (λex = 226 nm, λem = 366 nm), for concentrations between 0.10 and 1.0 μg mL?1. The method was performed in ethanol/water medium (30% V/V), at apparent pH 6.0 provided by adding of phosphate buffer solution with pH = 6.20.

The obtained values of detection and determination limits are 0.016 and 0.054 μg mL?1, respectively.

The method was successfully applied to assay a commercial injection containing nafcillin sodium monohydrate.  相似文献   

9.
There has been no assessment of the greenness of the described analytical techniques for the simultaneous determination (SMD) of caffeine and paracetamol. As a result, in comparison to the greener normal-phase high-performance thin-layer chromatography (HPTLC) technique, this research was conducted to develop a rapid, sensitive, and greener reversed-phase HPTLC approach for the SMD of caffeine and paracetamol in commercial formulations. The greenness of both techniques was calculated using the AGREE method. For the SMD of caffeine and paracetamol, the greener normal-phase and reversed-phase HPTLC methods were linear in the 50–500 ng/band and 25–800 ng/band ranges, respectively. For the SMD of caffeine and paracetamol, the greener reversed-phase HPTLC approach was more sensitive, accurate, precise, and robust than the greener normal-phase HPTLC technique. For the SMD of caffeine paracetamol in commercial PANEXT and SAFEXT tablets, the greener reversed-phase HPTLC technique was superior to the greener normal-phase HPTLC approach. The AGREE scores for the greener normal-phase and reversed-phase HPTLC approaches were estimated as 0.81 and 0.83, respectively, indicated excellent greenness profiles for both analytical approaches. The greener reversed-phase HPTLC approach is judged superior to the greener normal-phase HPTLC approach based on numerous validation parameters and pharmaceutical assays.  相似文献   

10.
《Analytical letters》2012,45(2):251-258
Two methods are described for simultaneous determination of amlodipine besylate and olmesartan medoxomil in formulation. The first method was based on the HPTLC separation of two drugs on Merck HPTLC aluminium sheets of silica gel 60 F254 using n-butanol: acetic acid: water (5:1:0.1, v/v/v) as the mobile phase. The second method was based on the HPLC separation of the two drugs on the RP-PerfectSil-100 ODS-3–C18 column from MZ-Analysetechnik GmbH, Germany and acetonitrile/0.03 M ammonium acetate buffer (pH = 3) in a ratio of 55:45 as the mobile phase. Both methods have been applied to formulation without interference of excipients of formulation.  相似文献   

11.
JPC – Journal of Planar Chromatography – Modern TLC - An HPTLC method, using an internal standard, for analysis of colchicine in a pharmaceutical formulation, has been established and...  相似文献   

12.
JPC – Journal of Planar Chromatography – Modern TLC - A new HPTLC method has been developed for identification and quantification of folic acid, N-[4-{[(2-amino-4-hydroxy-6-pteridynyl)...  相似文献   

13.
《Analytical letters》2012,45(11):1552-1570
Abstract

A high-performance thin-layer chromatographic method (HPTLC) for the simultaneous determination of lamivudine and zidovudine in a binary mixture has been developed. The method developed was based on HPTLC separation of the two drugs followed by densitometric measurements of spots at 276 and 271 nm for lamivudine and zidovudine, respectively. Separation was carried out on Merck HPTLC silica-gel 60 F254 plates, using toluene/chloroform/methanol (1:6:3 v:v) as the mobile phase. Validation of the method was performed based on The International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) guidelines in terms of linearity, accuracy, precision, limit of detection, limit of quantification, and robustness. Second-order polynomial equations were obtained for the regression line in the ranges of 250–1400 and 250–1700 ng/spot for lamivudine and zidovudine respectively. Correlation coefficient (r) values were 0.9998 for both analytes. The method provides sufficient accuracy as indicated by recovery percentages given for lamivudine and zidovudine. For system precision study, the low coefficient of variation values (<2%) for both lamivudine and zidovudine ensured reproducible performance of the instrument. In the method precision study, coefficients of variation <2% were obtained, which showed that the proposed method provides acceptable intraday and interday variation. The detection and quantification limits and were 3.06 and 9.28 ng/spot for lamivudine and 3.34 and 10.13 ng/spot for zidovudine, respectively. Parameters such as mobile-phase composition, volume of mobile phase, time from spotting to development, and time from development to scanning were employed while testing for robustness of the method, and the standard deviation of peak areas was calculated for each parameter. The low coefficient of variation values indicated the robustness of the method. Statistical manipulation did not show any significant effect of one parameter over the others on the robustness of the method.  相似文献   

14.
P. D. Bari  A. R. Rote 《Chromatographia》2009,69(11-12):1469-1472
Two new, rapid, precise, accurate and specific chromatographic methods were described for the simultaneous determination of olmesartan medoxomil and hydrochlorothiazide in combined tablet dosage forms. The first method was based on reversed phase liquid chromatography using an Eurosphere 100 RP C18 column (250 × 4.6 mm ID, 5 μm). The mobile phase was methanol–0.05% o-phosphoric acid (60:40 v/v) at a flow rate of 1.0 mL min?1. Commercially available tablets and laboratory mixtures containing both drugs were assayed and detected using a UV detector at 270 nm. The second method involved silica gel 60 F254 high performance thin layer chromatography and densitometric detection at 254 nm using acetonitrile–ethyl acetate–glacial acid (7:3:0.4 v/v/v) as the mobile phase. Calibration curves ranged between 200–600 and 125–375 ng spot?1 for olmesartan and hydrochlorothiazide, respectively.  相似文献   

15.
Canagliflozin (CNZ) is the first sodium–glucose co-transporter-2 inhibitor approved for treatment of type 2 diabetes mellitus. In the proposed work, a sensitive, rapid and validated high-performance thin-layer chromatography (HPTLC) method was established for the estimation of CNZ in human plasma for the first time. HPTLC analysis of CNZ and internal standard (sildenafil) was performed on glass coated silica gel 60 F254 HPTLC plates using a binary mixture of chloroform–methanol 9:1 (%, v/v) as the mobile phase. Densitometric detection was done at 295 nm. Retardation factor values were obtained as 0.22 and 0.52 for the CNZ and the IS, respectively. The linearity range of CNZ was obtained as 200–3,200 ng/ml. A simple protein precipitation method was used for the extraction of analyte from plasma using methanol. The proposed HPTLC technique was validated for linearity, accuracy, precision and robustness. The proposed HPTLC technique was successfully utilized for the assessment of pharmacokinetic profile of CNZ in rats after oral administration. After oral administration, the peak plasma concentration of CNZ was obtained as 1458.01 ng/ml in 2 h. The proposed HPTLC method could be applied to the study of the pharmacokinetic profile of pharmaceutical formulations containing CNZ.  相似文献   

16.
Bari  P. D.  Rote  A. R. 《Chromatographia》2009,69(11):1469-1472

Two new, rapid, precise, accurate and specific chromatographic methods were described for the simultaneous determination of olmesartan medoxomil and hydrochlorothiazide in combined tablet dosage forms. The first method was based on reversed phase liquid chromatography using an Eurosphere 100 RP C18 column (250 × 4.6 mm ID, 5 μm). The mobile phase was methanol–0.05% o-phosphoric acid (60:40 v/v) at a flow rate of 1.0 mL min−1. Commercially available tablets and laboratory mixtures containing both drugs were assayed and detected using a UV detector at 270 nm. The second method involved silica gel 60 F254 high performance thin layer chromatography and densitometric detection at 254 nm using acetonitrile–ethyl acetate–glacial acid (7:3:0.4 v/v/v) as the mobile phase. Calibration curves ranged between 200–600 and 125–375 ng spot−1 for olmesartan and hydrochlorothiazide, respectively.

  相似文献   

17.

A simple, sensitive, selective, precise and stability indicating high-performance thin-layer chromatographic method was developed for the determination of tamsulosin (TAM) in bulk and tablet formulation. Validation was carried out in compliance with International Conference on Harmonization guidelines. The method employed thin-layer chromatography aluminium plates pre-coated with silica gel 60F254 as the stationary phase and the mobile phase consisted of acetonitrile/methanol/dichloromethane (2.0: 1.0: 2.0, v/v/v). This solvent system was found to give compact spots for tamsulosin (R f = 0.27 ± 0.02). Densitometric analysis of TAM was carried out in the absorbance mode at 286 nm. Linear regression analysis showed good linearity (r 2 = 0.9993) with respect to peak area in the concentration range of 300–800 ng per band. The method was validated for precision, accuracy, ruggedness and recovery. Limits of detection and quantitation were 8.49 and 25.72 ng per band, respectively. TAM was subjected to acid and alkali hydrolysis, oxidation, photo degradation, dry heat and wet heat treatment. The drug underwent degradation under acidic, basic and photolytic conditions. The degraded products were well separated from the pure drug. Statistical analysis proved that the developed method, used for quantification of TAM as a bulk drug and present in pharmaceutical tablets, was reproducible and selective.

  相似文献   

18.
A simple, sensitive, selective, precise and stability indicating high-performance thin-layer chromatographic method was developed for the determination of tamsulosin (TAM) in bulk and tablet formulation. Validation was carried out in compliance with International Conference on Harmonization guidelines. The method employed thin-layer chromatography aluminium plates pre-coated with silica gel 60F254 as the stationary phase and the mobile phase consisted of acetonitrile/methanol/dichloromethane (2.0: 1.0: 2.0, v/v/v). This solvent system was found to give compact spots for tamsulosin (R f = 0.27 ± 0.02). Densitometric analysis of TAM was carried out in the absorbance mode at 286 nm. Linear regression analysis showed good linearity (r 2 = 0.9993) with respect to peak area in the concentration range of 300–800 ng per band. The method was validated for precision, accuracy, ruggedness and recovery. Limits of detection and quantitation were 8.49 and 25.72 ng per band, respectively. TAM was subjected to acid and alkali hydrolysis, oxidation, photo degradation, dry heat and wet heat treatment. The drug underwent degradation under acidic, basic and photolytic conditions. The degraded products were well separated from the pure drug. Statistical analysis proved that the developed method, used for quantification of TAM as a bulk drug and present in pharmaceutical tablets, was reproducible and selective.  相似文献   

19.
Cholesteryl oleate present as a neutral lipid in low‐density lipoprotein has been speculated to be a biomarker for atherosclerosis. Methods which are at hand for the quantification of cholesteryl oleate are either costly or entail the use of radioactive compounds. Charring of TLC plates has been used to identify cholesteryl esters for a long time but has never been applied to quantification of cholesteryl esters in biological matrices. Here, we report a novel method based on planar chromatography for the analysis of the products of the acyl CoA–cholesterol acyltransferase (ACAT) assay, viz. cholesteryl esters. Using silica gel 60 F254 as stationary phase, compounds were spotted on the plate and run using a solvent system comprising n‐hexane–diethyl ether–glacial acetic acid (90:10:1, v/v/v). The plates were developed by dipping in anisaldehyde–sulfuric acid reagent and were scanned at 546 nm for quantification. The developed method shows good linear relationship in the concentration range of 100–500 ng/band with a correlation coefficient (r) value of 0.9996. The method was validated for accuracy, precision and robustness. Percentage recovery of the method was found to be in the range 96.88–103.01% with intra‐ and inter‐day precision analysis yielding <2% relative standard deviation at nominal concentrations for analysis. The limits of detection and quantification were found to be 6.45 and 19.54 ng, respectively. The method was validated for robustness by making deliberate changes in mobile phase composition, volume and temperature of analysis, and the standard deviations of peak areas for these intentional changes were found to be 1.07, 1.02 and 1.30 respectively. The method was applied to the estimation of cholesteryl esters in plasma samples from patients diagnosed with hypercholesterolemia. No interferences were found from the biological matrices used in the assay. The proposed method could be of immense potential for estimation of cholesteryl oleate as a marker of ACAT activity, for screening of ACAT inhibitors in drug discovery process and in the prognosis of atherosclerosis. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

20.
《Analytical letters》2012,45(10):1731-1741
Abstract

A method for simultaneous analysis of pyridoxine and melatonin by second and third derivative UV - spectroscopy, the “zero - crossing” technique, is described. The determination has been carried out in 0.1 mol dm?3 hydrochloric acid solution and the concentration range of 2 – 10 μg/ml pyridoxine and 0.5 – 3.5 μg/ml melatonin. Lower limits of detection at the 95% confidence level were 0.26 μg/ml for pyridoxine and 0.05μg/ml for melatonin The advantages of the proposed method include its application for the assay and in-vitro dissolution studies of pyridoxine and melatonin from two different tablet formulations.  相似文献   

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