We describe a modified method for assay of t-aminocaproic acid. Serum or cerebrospinal fluid is deproteinized, followed by cation-exchange column-chromatography, and N-trifluoroacetyl-n-butyl derivativesof amino acids are formed and separatedby gas chromatography.Tranexamic acid,a nonproteinamino acid,was used as an internal standard.The assay issensitiveand precise,and results correlate adequa...

The optimal composition of eluant for trifluoroacetic acid (TFAA) analysis by ion-exchange chromatography was determined and a preliminary study to detect TFAA, a metabolite of isoflurane, in bile of rabbits during and after inhalation of isoflurane was made. The optimal composition of eluant for TFAA analysis by ion-exchange chromatography was determined to be a solution of 2mM Na2CO3 and 4mM ...

We have established a procedure for removing interfering materials from extracts of geological and biological samples, in order to determine precise compound-specific nitrogen isotopic compositions of amino acids. We employed cation-exchange chromatography of protein and non-protein amino acids prior to derivatization for gas chromatographic separation. The average recovery of a standard amino ...

The application of a 32P-postlabeling assay for 7-methylguanines in DNA was studied either by labeling the imidazole ring-opened dinucleotide derivatives or by using strong-anion-exchange column chromatography for the adduct enrichment from normal nucleotides. Data showed that 7-methylguanines can be efficiently labeled as dinucleotides when in vitro methylated DNA was first imidazole ring-open...

A novel preparation for polyethylene glycol (PEG) derivatives and chromatographic separation procedure of the PEGylated recombinant human granulocyte colony-stimulating factor (rhG-CSF) were designed to evaluate the reproducibility and scalability at large laboratory-scale level. The new "PEG-pellet" PEGylation mode was successfully applied to control the pH fluctuation during the conjugation r...

Background: Benzaldehyde dehydrogenase (BZDH) is encoded by the xylC that catalyzes the conversion of benzaldehyde into benzoate in many pathways such as toluene degradation. Objectives: In this study, the xylC gene from Rhodococcus ruber UKMP-5M was expressed in Escherichia coli, purified, and characterized.Materials and Methods: The xylC was amplified and cloned in E. coli. The re...

9-Aminononanoic acid, 9-aminononanamide, and related compounds derived from soybean oil by reactions, including reductive ozonolysis and reductive amination, were separated on an analytical scale either by gas liquid chromatography of trifluoroacetylated or trimethylsilylated derivatives or by thin layer chromatography and on a preparative scale by ion-exchange chromatography. Comparative analy...

A blocker of postsynaptic acetylcholine receptors was isolated from venom of the Eastern green mamba Dendroaspis angusticeps, by gel filtration, ion-exchange and reverse phase high performance liquid chromatography. The isolated component blocks neuromuscular transmission and responses to exogenously applied acetylcholine in isolated chick biventer cervices preparations. These results suggest t...