摘要:

5-Hydroxyindoleacetic acid (5HIAA), a metabolite of serotonin is utilized clinically to detect the carcinoid tumors. A simple method for determination of 5HIAA in urine, serum, and cerebrospinal fluid (CSF) is described. For quantitation in urine, the method is based on a single step extraction followed by separation on an anion exchange short column. This type of column enabled the direct injection of the organic solvent on the column without any interference in the spectra or symmetry of the peak. For serum and (CSF) analysis acetonitrile deproteinization was used with injection on the same column. 5HIAA was detected by its native fluorescence which was more sensitive and more suited for daily routine analysis compared to the more common electrochemical detection. Reference range for 5HIAA in different human fluids is determined. Patients with carcinoid syndrome showed elevated levels of 5HIAA in both urine and serum.

ISSN:1082-6076    

DOI:10.1081/JLC-100100461

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

A new method for PAHs determination in toasted bread samples is proposed. The method is based on supercritical-fluid extraction, using CO2and acetonitrile as modifier. The extracted PAHs were collected in 1 mL acetonitrile. Quantitation was carried out by HPLC with fluorimetric detection. A Hypersil Green PAH column, acetonitrile-water gradient mobile phase, and a program of 11 excitation and emission wavelength pairs for fluorimetric detection were used. Recoveries at concentration levels in the range 0.15–3.56 μg/kg bread were close to 100% for all PAHs except fluoranthene, chrysene, and benzo[ghi]perylene. Some PAHs were detected in these samples within the range 0.323–9.40 μg/kg toasted bread; the relative standard deviations were in the range 2 – 12% (n=4).

ISSN:1082-6076    

DOI:10.1081/JLC-100100462

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor