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Drug Substance and Excipient Characterization
Published in Dilip M. Parikh, Handbook of Pharmaceutical Granulation Technology, 2021
Parind M. Desai, Lai Wah Chan, Paul Wan Sia Heng
In liquid chromatography, the affinity of the material for the solid stationary phase in a column governs the time taken by the material to elute from the column. The time of elution is used to identify the material. Solutions of the drug, excipient, and drug–excipient mixture are prepared and injected separately into the column. The concentration of the material that elutes from the column is detected and plotted against time to give a chromatogram. If there is interaction between the drug and excipient, the complex formed will exhibit an elution time different from those of the individual components (Figure 3.14). Similarly, gas chromatography may be used for volatile components.
Analysis of Essential Oils
Published in K. Hüsnü Can Başer, Gerhard Buchbauer, Handbook of Essential Oils, 2020
Adriana Arigò, Mariosimone Zoccali, Danilo Sciarrone, Peter Q. Tranchida, Paola Dugo, Luigi Mondello
At the outlet of the chromatography column, the analytes emerge separated in time. The analytes are then detected and a signal is recorded generating a chromatogram, which is a signal vs. time graphic ideally with peaks presenting a Gaussian distribution-curve shape. The peak area and height are a function of the amount of solute present, and its width is a function of band spreading in the column (Ettre and Hinshaw, 1993), while its retention time can be related to the solute's identity. Hence, the information contained in the chromatogram can be used for qualitative and quantitative analysis.
UV/V is Spectrophotometric Characterization of the Leaf Polyphenolics Content in Elaeocarpus tectorius and its Therapeutic Potential against Selected Urinary Tract Infection Pathogens
Published in Parimelazhagan Thangaraj, Phytomedicine, 2020
M. Ashwini Lydia, Suman Thamburaj, Gayathri Jagadeesan, Gayathri Nataraj, Kasipandi Muniyandi, Saikumar Sathyanarayanan, Parimelazhagan Thangaraj
The Silica gel 60 F254 (Merck, Germany) was used for the thin layer chromatography (TLC) analysis of E. tectorius ethyl acetate and the methanol leaf extract. The silica plates (8 × 3 cm size) were activated at 120°C for 2 minutes and then used. The extracts to be separated were spotted (5 μL from 1 mg/mL concentration of extracts) with a capillary tube, 1.0 cm above from the end of the silica gel plate, which was in contact with the solvent hexane: ethyl acetate: methanol (60:30:10%). After spotting, the TLC plates were kept in a chamber containing the solvent. A chromatogram was developed by the movement of the solute (mobile phase) across a thin layer of silica (stationary phase). After the development of a chromatogram, the resolved spots were revealed by detection under UV light at a longer wavelength (365 nm) and a shorter wavelength (254 nm), which helped to detect the compound (colored compounds and fluorescence compounds).
Therapeutic effects of Bombax ceiba flower aqueous extracts against loperamide-induced constipation in mice
Published in Pharmaceutical Biology, 2023
Liuping Wang, Shiyuan Xie, Xuan Jiang, Caini Xu, Youqiong Wang, Jianfang Feng, Bin Yang
In this study, the base peak chromatogram obtained is illustrated in Figure 1. The samples in negative ion mode showed stronger peak signals and rich mass information, so the peaks in negative ion mode we analysed to identification of the chemical composition in BCE. Based on the retention times, molecular formula, the MS/MS data, reference standards and literature data, 12 compounds were identified which include: protocatechuic acid, 1-caffeoylquinic acid, 5-coumaroylquinic acid, neochlorogenic acid, chlorogenic acid, 4-coumaroylquinic acid, 3-coumaroylquinic acid, clovamide, rutin, isoquercetin, quercetin 3-glucuronide and kaempferol-3-glucuronide (Table 2). Among them, three compounds, including protocatechuic acid, chlorogenic acid and rutin were unambiguously identified by comparing with the retention time and MS data of reference standards. In addition to the above compounds, some peaks of fatty acids were found in the chromatogram of BCE after 10 min.
Antibacterial activity of essential oils for combating colistin-resistant bacteria
Published in Expert Review of Anti-infective Therapy, 2022
Abdullah M. Foda, Mohamed H. Kalaba, Gamal M. El-Sherbiny, Saad A. Moghannem, Esmail M. El-Fakharany
The total ionization chromatogram showed that the retention time of the components ranged between 4 and 42 min, most of which were concentrated between 5 mins to 22 mins as in Figure 1(b). The retention index of the tested sample and its mass spectrum results were compared with those of standard libraries (NIST and Wiley) and the literature. The analyzed sample of cinnamon oil was found to contain 15 compounds represented as seven major compounds and eight minor ones according to the peak area percentages. The major compounds that are identified in cinnamon oil are benzaldehyde (2.34%), benzene acetaldehyde (1.56%), 3-phenyl propionitrile (4.27%), cinnamaldehyde (E)- (40.91%), 3-phenyl acrylaldehyde (8.70%), cinnamaldehyde dimethyl acetal (37.54%), and trans-cinnamic acid (1.49%). According to the literature, these compounds have different biological activities, such as antimicrobial, antioxidant, anti-inflammatory, anticancer, anti-leishmania, anti-Virulence, anti-acnes, and Insecticidal activities. The bioactive compounds are identified and their retention time, peak area, molecular weight, molecular formula, chemical structure, and biological activity are demonstrated in Table 6.
The Anticancer Effect of Inula viscosa Methanol Extract by miRNAs’ Re-regulation: An in vitro Study on Human Malignant Melanoma Cells
Published in Nutrition and Cancer, 2022
Dilara Kamer Colak, Unal Egeli, Isil Ezgi Eryilmaz, Onder Aybastier, Hulusi Malyer, Gulsah Cecener, Berrin Tunca
Chromatographic analysis of IVM and IVW was carried out using an HPLC-DAD system (Agilent 1200, Waldbronn, Germany) by OA from the Analytical Chemistry Department. The separation of phenolic compounds was realized using the mobile phase formed by dissolving formic acid (solvent A) and acetonitrile (solvent B) in 1% H2O using column XBridge C18 (4.6 × 250 mm, 3.5 μm; Elstree, UK). 13% ml B between 0 and 10 min, 41.5% B between 10 and 20 min, 70% B between 20, and 25 min and 10% B between 25 and 35 min in total at 10 injection volumes of 0.5 ml/min column flow rate was performed. Data were collected using Chemstation for LC (Agilent, Waldbronn, Germany). It was determined which phenolic compound each peak belongs by comparing the retention times of the phenolic standards and the UV spectra. The quantities of compounds were determined by calculating chromatogram areas.