results under the above chromatography condition, biuret compound (peqb) and the internal standard were detected at 4.5 and 13.5 minutes, respectively. limit of quantitation of the peqb was 0.1 µg/ml. accuracy of the method over the concentration range of 0.1-100 µg/ml was between 88-109%. inter- and intraday precisions were 4-19% and 6-8%, respectively. a good relationship in the form of a pow...

in this study, for the analysis of human urine samples, a novel method explained for the determination of celecoxib, a nonsteroidal anti-inflammatory drug (nsaid), using molecularly imprinted solid-phase extraction (mispe) coupled with high-performance liquid chromatography (hplc). the synthesis of the mip was performed by precipitation polymerization in methacrylic acid (maa), ethylene glycol ...

a solid phase extraction sorbent based on polyaniline/graphene nanocomposite is presented. the structure and morphology of synthesized nanocomposite were investigated by fourier transform infrared spectroscopy, field emission scanning electron microscopy, x-ray diffraction and thermal gravimetric analysis. the dispersive solid phase extraction was employed to the isolation and preconcentration ...

gamma-aminobutyric acid is the main inhibitory amino acid neurotransmitter in several areas of the brain. measurement of gamma-aminobutyric acid in the brain will help elucidate its metabolic rote and diagnostic value. the liquid chromatography (lc) system consisted of a delivery pump. male rats (150-250g) were used in this study. the brain was rapidly removed from decapitated animals. trie chr...

objective(s):the present study reports the development and validation of a sensitive and rapid extraction method beside high performance liquid chromatographic method for the determination of crocetin in human serum. materials and methods:the hplc method was carried out by using a c18 reversed-phase column and a mobile phase composed of methanol/water/acetic acid (85:14.5:0.5 v/v/v) at the flow...

background and objectives:  high concentration of preservatives in food may result in gastrointestinal disturbances whereby some patients suffering from asthma, rhinitis, or urticaria. the aim of this study is the introduction and optimization a new method for simultaneous determination of four preservatives (sb, ps, mp, pp) in foodstuff by high performance liquid chromatography. materials and ...

The rates at which biological interactions occur can provide important information on the mechanism and behavior of such processes in living systems. This paper will discuss how affinity chromatography can be used as a tool to examine the kinetics of biological interactions. This approach, referred to here as biointeraction chromatography, uses a column with an immobilized binding agent to exam...

this article describes a simple and fast high-performance liquid chromatography method for the determination of methotrexate (mtx) in plasma. samples were collocted from children receiving high-dose mtx at shafa hospital (ahvaz university of medical sciences, ahvaz, iran) at various times after the end of eachinfusion. plasma was deproteinized with trichloroacetic acid and the supernatant was i...

an accurate and sensitive reversed-phase high-performance liquid chromatograph-ic method for determination of sertraline in human serum is described using 4-chloro-7-nitrobenzofurazan as pre-column derivatization agent. the drug and an internal standard (azithrimycin) were extracted from serum using a mixture of diethyl ether-chloroform and subjected to the pre-column derivatization with the re...