High‐performance liquid chromatographic method for determination of leucovorin in plasma: validation and application to a pharmacokinetic study in healthy volunteers

Abstract

A sensitive and reliable high-performance liquid chromatographic (HPLC) method, using a solid-phase extraction (SPE), was developed and validated for determination of leucovorin (LV) in human plasma. Plasma sample was extracted by using a Sep-Pak cartridge which could be renewable. The sample was analyzed by HPLC with UV detection at 286 nm. The method was shown to perform selectively and sensitively for LV. The main metabolite of LV, 5-methyltetrahydrofolic acid, and endogenous substances in plasma did not show any interference in the analysis. The limit of detection was 10 ng/mL for LV in plasma and the linear range was 50-1500 ng/mL in plasma. The relative standard deviation (RSD) of intra-day and inter-day assays was 2.8-6.1% and 2.4-5.3%, respectively. The extraction recoveries of LV in plasma were over 90%. The method was proved to be applicable to the pharmacokinetic study of LV in healthy volunteers after a single oral administration (75 mg). The pharmacokinetic parameters and relative bioavailability were investigated for domestic LV tablet and capsule vs an imported tablet.

Use of fullerene‐, octadecyl‐, and triaconthyl silica for solid phase extraction of tryptic peptides obtained from unmodified and in vitro glycated human serum albumin and fibrinogen

“…The most widely used SPE materials in the field of bioanalytical research are silica-based C18 RP sorbents since the introduction of Sep-Pak cartriges in 1978 [11], despite some drawbacks of using alkylated silica (low recovery for basic analytes, relatively low capacity, poor wettabil-ity, etc.) [12].…”

“…Fractionation prior to analyses can have a significant effect on sequence coverage of proteins particularly implemented for those peptides obtained from the proteolysis of larger proteins [9]. Further advantages of the SPE method include relatively high recovery rate, short extraction time, high enrichment factor and low consumption of organic solvents [10,11].…”

Electrocatalytic Oxidation of Calcium Folinate on Carboxyl Graphene Modified CuxO/Cu Electrode

“…Calcium folinate (CF), also known as leucovorin calcium, is an active metabolic intermediate of folic acid. In clinical, CF commonly served as an antidote [1,2] to methotrexate, an antineoplastic agent [3], in order to alleviate the side effect of high concentration of methotrexate [4]. Another application of CF is in cooperation with fluorouracil to improve the reactivity of fluorouracil [1].…”

“…Thus, a fast, sensitive and reliable assay method for the determination of CF is necessary. The proposed methods that have been reported for the detection of calcium folinate were mainly highperformance liquid chromatography (HPLC) which was combined with solid-phase extraction and detection with fluorescence [1] or ultraviolet (UV) [2], capillary electrophoresis (CE) [5] and so on. There also have developed many methods for simultaneous determination of CF, methotrexate and other similar structure compounds, such as HPLC with fluorescence or UV [1,3,6], CE with UV [7], LC with electrospray ionization mass spectrometry (ESI-MS) [4], LC-MS [8], etc.…”

Pipette-tip selective extraction of glycoproteins with lectin modified gold nano-particles on a polymer monolithic phase

“…Generally, it is applied to the 30 selective capture and preconcentration of the target analyte and/or the removal of potentially interfering components from the sample matrix. [1][2][3][4] SPE has been applied as a sample preparation strategy both for small molecules (pharmaceutical, pesticides etc) as well as larger biomolecules (peptides, proteins etc). SPE 35 devices usually comprise a selective adsorbant material encased within a housing such that the sample and subsequent elution buffers can be passed through the bed for collection and analysis.…”