extraction from serum sample. The humanserum standards for calibration were prepared by spiking the standard working solution and IS solution (20 μL of 100 μg/mL; 2 μg) into a pool of blank humanserum (final volume of 100 μL). QC samples at 4 concentrations
Authors:A. Plenis, L. Konieczna, I. Olędzka, and P. Kowalski
A simple and rapid high-performance liquid chromatographic method with fluorescence detection for analysis of loratadine (LOR) in small volumes of human serum has been developed and validated. After solid-phase extraction (SPE), with thioridazine hydrochloride as internal standard, chromatographic separation was performed on a C18 analytical column with 70:30 (v/v) acetonitrile-water, adjusted to pH 2.7 with orthophosphoric acid as mobile phase at a flow-rate of 1 min mL−1. The column was maintained at 28°C. Fluorescence detection was performed at excitation and emission wavelengths of 265 of 454 nm, respectively. The method was validated for accuracy, precision, selectivity, linearity, recovery, and stability. Absolute recovery of LOR was >93.0%. The limits of detection (LOD) and quantification (LOQ) were 0.07 and 0.2 ng mL−1, respectively. Linearity was confirmed in the range 0.2–30 ng mL−1 (correlation coefficient >0.9998). This HPLC method is selective, robust, and specific and would enable efficient analysis of large numbers of serum samples in support of pharmacokinetic, bioavailability, or bioequivalence studies after therapeutic doses of LOR.
Authors:Akifumi Eguchi, Takeshi Enomoto, Norimichi Suzuki, Miho Okuno, and Chisato Mori
from all donors. This study was approved by the Ethics Committee of Chiba University, Japan. Humanserum samples ( n = 26) were collected from Chiba Prefecture, Japan [ 16 ]. Whole blood samples were collected by a certified physician, and serum
Authors:K. Wróblewski, A. Petruczynik, B. Buszewski, M. Szultka-Młyńska, H. Karakuła-Juchnowicz, and M. Waksmundzka-Hajnos
Vortioxetine is a new drug against major depressive disorder with high affinity for a range of different serotonergic targets in the central nervous system. Therapeutic drug monitoring is an important tool for the clinical management of patients receiving a pharmacotherapy, particularly in psychiatry. For this reason, determination of drug concentration in biological fluids is important for a rational dosage of drugs. Rapid and reliable analytical assays are also required to detect and identify drugs of toxicological importance. For analysis of vortioxetine by high-performance liquid chromatography (HPLC), no procedures for its determination in saliva have been reported and there are only a few ones for its determination in serum. A sensitive and selective highperformance liquid chromatography with diode array detector (HPLC-DAD) or mass spectrometer (HPLC-MS) method was developed for the fast quantification of vortioxetine in human saliva and serum. The determination was performed on a Synergi Polar RP column in isocratic mode under the optimal mobile phase containing 70% methanol, 20% acetate buffer at pH 3.5, 10% double distilled water, and 0.025 M L−1 diethylamine.
Authors:A. Petruczynik, K. Wróblewski, and M. Waksmundzka-Hajnos
behavior. The effect of the concentration of IL or acetonitrile in mobile phases and effect of temperature was investigated and optimal eluent for analysis of psychotropic drugs in humanserum was chosen.
by Wako Pure Chemical Industries Ltd. Humanserum was purchased from MP Biomedicals Inc., and serum samples obtained from the patient were maintained at −20°C until required for analysis. MonoSpin C 18 and C 18 -CX were purchased from GL Science
Authors:Fatema Moni, Suriya Sharmin, Satyajit Roy Rony, Farhana Afroz, Shammi Akhter, and Md. Hossain Sohrab
, accurate, and precise method for determination of Esomeprazole in humanserum using HPLC suitable for Pharmacokinetic study, Bioavailability, and Bioequivalence study. Experimental Chemicals Esomeprazole and Pantoprazole (Internal standard, IS) were kindly
Authors:Liwei Cao, Lizhen Wu, Hailan Zhong, Hao Wu, Siyun Zhang, Jianxin Meng, and Fengyu Li
detection. Sample analysis In order to verify the feasibility of the established methods, the experiments were performed on spiked recovery tests in humanserum and urine. Fig. 5 and Fig. 6 show the chromatograms and electropherograms of serum and urine
Authors:D. Suchy, K. Łabuzek, O. Pierzchała, and B. Okopień
Ezetimibe is the first in a new class of antihypercholesterolemic drugs. Since it has not long been available on the market, many of its properties may still be revealed. Analytical methods for its determination are scarce, especially regarding serum samples. A simple, fast, and effective high-performance liquid chromatography-ultraviolet (HPLC-UV) method for the determination of ezetimibe concentration in human serum has therefore been developed. Three mobile phases were analysed, and original modifications to the concentration and flow parameters were made. Of five potential internal standards (IS), only nitrendipine was found to be suitable. The analytical wavelength was chosen based on the absorption spectrum of ezetimibe in the mobile phase. Finally, an extraction analysis was performed using two different solvents, and the extrahent volume was optimised. The final method developed was as follows. Single extraction of 1 mL serum sample, spiked with IS, was performed using 10 mL of methyl-t-butyl ether. Separation was obtained at ambient temperature on a Waters C18 Symmetry Shield (4.6 mm × 250 mm, 5 μm) column. The isocratic mobile phase was composed of acetonitrile and 0.1 M ammonium acetate aqueous solution 55:45 (v/v), set at flow rate of 0.75 mL min−1. Ezetimibe was detected at a wavelength of 232 nm after 5.49 min, and the IS was detected at 8.05 min. The developed method has been validated according to ICH standards. It was found to be specific, precise, accurate and linear over the range 10–800 ng mL−1 with R2 > 0.998, and detection and quantification limits of 4.60 ng mL−1 and 13.94 ng mL−1, respectively. The method has been applied to clinical serum samples. The developed technique allowed for successful in vivo assessment of ezetimibe concentrations in samples obtained from hypercholesterolemia patients who are chronically receiving the drug.