An analytical method has been developed for the determination of glyphosate herbicide and its metabolite aminomethylphosphonic acid (AMPA) in natural waters to a level of 0.10 μg/L with a good linearity in the range 0.10-2.00 μg/L and coefficients of variation under 20 % for each spiked level. The procedure involves a precolumn derivatization step with 9-fluorenylmethylchloroformate (FMOC-Cl) y...

Chiral separation of 19 pairs of amino acid (AA) enantiomers derivatized with 9-fluorenylmethylchloroformate (FMOC) was successfully conducted by capillary electrophoresis using the mixture of beta-CD and sodium taurodeoxycholate (STDC) as selectors. Resolution was considerably superior to that obtained by using either beta-CD or STDC alone. After a systematic inspection, a buffer composed of 1...

Chitin is a polysaccharide component of the inner cell wall fungi that has been used to estimate fungal invasion in plant products. However, its detection major pathogenic species not investigated. The present study aimed determine chitin contents order evaluate diagnostic potential as biomarker for infections. High performance liquid chromatography (HPLC) was measure content. Pure acid hydroly...

A sensitive high-performance liquid chromatographic (HPLC) assay using fluorescence detection for quantifying lidocaine levels in plasma (in the ng/ml range) was developed. This novel HPLC assay has made possible the simultaneous monitoring of lidocaine levels in coronary and peripheral plasma obtained after myocardial controlled-release matrix administration (0.92 mg/kg during 4 h) in the arrh...

9-Fluorenylmethyloxycarbonyl (FMOC) derivatives of catecholamines, including dopamine (DA; 3,4-dihydroxyphenethylamine), norepinephrine (NE; 2-amino-1-(3,4-dihydroxyphenyl)ethanol) and epinephrine (EPI; 1-phenyl-1-hydroxy-2-methylaminopropane) as well as 3, 4-dihydroxybenzylamine (DHBA) have been analyzed using high performance liquid chromatography coupled to fluorometric detection and atmosph...

The dipeptide L-carnosine has a number of important biological properties. Here, we explore the effect of attachment of a bulky hydrophobic aromatic unit, Fmoc [N-(fluorenyl-9-methoxycarbonyl)] on the self-assembly of Fmoc-L-carnosine, i.e., Fmoc-β-alanine-histidine (Fmoc-βAH). It is shown that Fmoc-βAH forms well-defined amyloid fibrils containing β sheets above a critical aggregation concentr...

Self-assembling nanostructured peptide gels are promising materials for sensing, drug delivery, and energy harvesting. Of particular interest short diphenylalanine (FF) peptides modified with 9-fluorenylmethyloxycarbonyl (Fmoc), which promotes the association of building blocks. Fmoc-FF generally form fibrous networks while other structures have been demonstrated, further control gelation resul...

Human breast milk (BM) amino acid (AA) composition may be impacted by lactation stage or factors related to geographical location. The present cross-sectional study is aimed at assessing the temporal changes of BMAA over lactation stages in a large cohort of urban mothers in China. Four hundred fifty BM samples, collected in three Chinese cities covering eight months of lactation were analyzed ...

This work utilizes on-column ligand synthesis and affinity capillary electrophoresis (ACE) to determine binding constants ( K(b)) of 9-flourenylmethyloxy carbonyl (Fmoc)-amino acid derivatives to the glycopeptide antibiotics ristocetin (Rist) and teicoplanin (Teic). In this technique, two separate plugs of sample are injected on to the capillary column and electrophoresed. The initial sample pl...

This paper describes a two-step procedure whereby on-column ligand synthesis and partial-filling affinity capillary electrophoresis (PFACE) are sequentially coupled to each other to determine the binding constants of 9-fluorenylmethoxy carbonyl (Fmoc)-amino acid-D-Ala-D-Ala species to vancomycin (Van) from Streptomyces orientalis. In this technique four separate plugs of sample are injected ont...