Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 6

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
EN
A new High Performance Liquid Chromatography–Photodiode Array Detector (HPLC–PDA) method has been developed for the chromatographic separation and simultaneous quantitative determination of nine bioactive compounds, i.e. four phenolic (gallic acid, ellagic acid, chebulinic acid, and tannic acid), two flavanoids (rutin and quercetin), two anthraquinones (sennoside A and B) and one oxygenated hydrocarbon (vitamin C) in a well-known Unani polyherbal formulation namely Itrifal’s. Separation was accomplished on a C18 LiChrospher 100 column (5 mm, 250 3 4.6 mm) with a gradient elution and recorded at 254 nm. The results demonstrated that the proposed method is reproducible, accurate, economic, and suitable for the quality control of traditional polyherbal Unani formulations containing complex compounds with different structures such as Itrifals.
EN
In this research, a novel method was developed for the matrix solid phase dispersion (MSPD) followed by high-performance liquid chromatography (HPLC) quantification of four marker constituents (vitamin C, gallic acid, rutin, and ellagic acid) in the freeze-dried pomegranate fruit juice. Various MSPD parameters like type of dispersant, sample–dispersant ratio, solvents, its volume, and time of extraction have been optimized after many trials. Furthermore, HPLC method has been developed and optimized for the analysis of all four components. The HPLC separation was achieved using a 250 × 4.6 mm column, particle size of 5 μm, C18 reverse phase column, with a mobile phase consisting of acetonitrile and 0.05% H3PO4, in gradient elution mode with a mobile phase flow rate of 1 mL/min, using ultraviolet (UV)–visible detection at 254 nm. All calibration curves showed good linear regression (r2 ≥ 0.9925) within test ranges. The extraction recoveries of the marker constituents analyzed by MSPD methods were found as ranging from 97.5% to 103.5%. From comparing the chromatograms, validation data and other parameters like time, labor, and feasibility, we found that MSPD technique was most suitable for the analysis as compared to conventional liquid–liquid extraction technique.
EN
The alternative system of medicines like Unani and Ayurveda is preferred worldwide nowadays due to its therapeutic efficacy, lower side effects, holistic approach, psychological dimensions, and qualitative action of weather and seasonal requirement. A simple procedure is described for the simultaneous extraction and estimation of piperlongumine and piperine in a well-known Unani polyherbal formulation using reversed-phase high-performance liquid chromatography (HPLC). The chromatography was carried out on reversed-phase C18 (250 × 4.6 mm) column with a mobile phase containing acetonitrile—water (50:50 v/v). Detection was accomplished with ultraviolet (UV) detection at λ = 325 nm. The flow rate was kept as 1.0 mL−1. The proposed method was validated according to International Conference on Harmonization (ICH) guidelines for accuracy (94.4–105.0%), precision (0.37–2.17% RSD), and robustness (0.14–2.11% RSD). The limit of detection (LOD) values were found as 30 and 10 ng mL−1, while limit of quantification (LOQ) was 100 and 30 ng mL−1 for piperlongumine and piperine, respectively, which proved the sensitivity of the method satisfactory enough for accurate analysis of the both piperlongumine and piperine.
EN
High-performance thin-layer chromatography (HPTLC) method for the quantification of eugenol from nanostructured drug delivery systems was successfully developed and validated. The mobile phase consisted of n-hexane:acetone (7:3, v/v), and the densitometric scanning was performed in the absorbance mode at 280 nm. The method was valid with respect to linearity and range, accuracy, precision, specificity, detection limit (DL), and quantitation limit (QL). The linearity of the method was established by a correlation coefficient value of 0.9930 ± 0.0013. The precision was tested by checking intra-day (repeatability) and inter-day (intermediate precision) variations. The method was established to be precise by low relative standard deviation (RSD) values for different concentration of eugenol. The results of the recovery studies of eugenol from preanalyzed samples demonstrated the accuracy of the method. The specificity of the developed method for the analysis of eugenol in the nanoemulsion gel and nanoparticles samples was confirmed by comparing the spectra obtained in standard and sample analysis. The DL and QL were determined to be 31.41 and 95.17 ng band−1, respectively, for the HPTLC method. The forced degradation studies revealed on eugenol established the effectiveness of the developed and validated method. The developed and validated HPTLC method was found to be a stability-indicating one, as indicated by the results of forced degradation studies, for its use during the accelerated stability studies of the nanoemulsion gels and nanoparticles of eugenol.
EN
In this chapter, an isocratic reverse phase HPLC determination of mimosine was developed and validated in an anti-psoriatic topically applied formulation “Lajjalu”. The chromatography was performed on a C18 column with water-orthophosphoric acid (98.8:0.2, υ/υ) as a mobile phase with a pH of 3.0 at a flow rate of 1.0 mL min-1. Detection was performed at 284 nm, and a sharp peak was obtained for mimosine at a retention time of 2.62 ± 0.01 min. Linear regression analysis data for the calibration plot showed a good linear relationship between response curve and concentration in the range of 0.050–5000 ng mL-1 and the regression coefficient was 0.9998 with the linear regression equation y = 4766.8x−17726. The detection (LOD) and quantification (LOQ) limits were 10.3 and 35.6 ng mL-1, respectively. The wide linearity range, sensitivity, accuracy, short retention time, and simple mobile phase imply the method is suitable for routine quantification of mimosine with high precision and accuracy.
EN
A validated reversed-phase HPLC method has been developed for quantitative analysis of berberine in Berberis aristata fruits and in a polyherbal formulation. Separation of berberine was achieved on a C18 column with a mobile phase consisting of a 10–80% acetonitrile gradient in 0.05% aqueous orthophosphoric acid. The flow rate was 1 mL min-1. Detection was at 266 nm. A sharp, well defined peak was obtained at a retention time of 10.0 ± 0.4 min. The method was validated in accordance with ICH guidelines for accuracy, precision, robustness, and the limits of detection (LOD) and quantification (LOQ). Results from linear regression analysis were indicative of a good linear relationship (r2 = 0.998 ± 0.0011) in a wide concentration range (5–500 μ g mL-1). LOD and LOQ were 1.5 and 5.3 μg mL-1, respectively. Satisfactory recovery results (94.6–103.1%) were obtained by the method of standard addition. Intra-day, inter-day, and intersystem precision was satisfactory, with relative standard deviation in the range 0.7–1.8%. The berberine content of fruit of Berberis aristata and the herbal formulation were 0.033% and 0.0089% (w/w), respectively. This HPLC method for quantification of berberine can be used for quality control and standardization of several crude drugs and different herbal formulations in which berberine is present as a phyto constituent.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.