Authors:Ahmed K. Kammoun, Zuhier Ahmed Awan, Tarek Elawady, Alaa Khedr, and Mohamed I. El-Awady
samples at four concentration levels to study the analyte stability during the analysis (autosampler stability, 24 h) and three freeze and thaw cycles of QC samples stored at −80 °C along 30 days.
Authors:Xiaorong Wu, Yankai Wang, Binbin Liang, Honghai Wu, Liying Wu, Jing Song, and Jianfang Liu
pharmacokinetic studies of these preparations have been conducted in many countries, however, the pharmacokinetic studies of fenofibrate tablets (Lipanthyl® supra, 160 mg) in Chinese subjects have not been reported. Ultra-high performance liquid chromatography
Authors:Branislava Miljković, Branka Brzaković, Ivan Kovacević, Danica Agbaba, and Milena Pokrajac
A thin-layer chromatographic (TLC) method for quantitative analysis of nimesulide in human plasma has been developed, validated, and applied to a pharmacokinetic study of healthy volunteers. A previously published method has been modified and simplified (instead of two-step sample preparation a single step extraction procedure was employed) which makes the new method time-saving. Nimesulide plasma concentrations were analyzed after single-step extraction with dichloromethane. The sample preparation procedure described enables efficient extraction — recoveries were 99 ± 8% (mean ±
). Chromatography was performed on silica gel 60 F
TLC plates, developed with toluene-acetone, 100 + 10 (
) and evaluated densitometrically at
= 310 nm in reflectance-absorbance mode. The
was 0.5025. The method presented is characterized by high sensitivity (0.1 mg L
) and within-run and day-to-day coefficients of variation of 2.8–4.5% and 4.8–8.5%, respectively. The method was used to determine the pharmacokinetic profile of nimesulide in healthy volunteers after oral administration.
Authors:Neetika Taneja, Vikram Gota, Murari Gurjar, and Kamalinder K. Singh
models are commonly used for preclinical assessment to screen the anticancer activity and establish pharmacokinetics (PK) of the existing drug or newly developed formulations [ 22 , 23 ]. These models involve human cancer cell lines or tumor xenograft
Authors:A. Korde, M. Venkatesh, H. Sarma, and M. Pillai
Cerebral amino acid metabolism is known to be associated with various psychosomatic disorders. 3-(123I)iodo-L-alpha methyl tyrosine (123I-L-AMT) is an alternative to the PET radiopharmaceutical, 11C- thymidine, for brain SPECT studies. Radioiodination of L-alphamethyl tyrosine using chloramine T as well as iodogen has been standardized using 125I as the first step towards the development of the SPECT imaging agent 123I-L-AMT. Purification of the iodinated product was carried out over Sephadex LH-20 column. A quick and easy purification method using Sep-pak column also has been standardized. Quality control of the 125I-L-AMT was carried out by estimating the radiochemical purity and stability of the product. Biodistribution studies of the product were carried out in mice. Time dependent pharmacokinetic studies and activity distribution pattern in the different parts of the brain were also carried out.
A simple and rapid high-performance thin-layer chromatographic method has been established and validated for determination of ursolic acid in rabbit plasma after ingestion of an aqueous slurry of
R. Br. leaves. Chromatography was performed on silica gel HPTLC plates with toluene-ethyl acetate-triethyl-amine-methanol, 7 + 2 + 1 + 1 (
), as mobile phase. The plates were scanned densitometrically at
= 366 nm. The response to ursolic acid in spiked plasma was a linear function of concentration in the range 10 to 80 μg mL
. The detection and quantification limits were 3.0 and 10 μg mL
, respectively. The method has been successfully used to study the pharmacokinetics of
R. Br. using ursolic acid as a marker.