Abstract |
We developed sample preparation methods for the detection of various biogenic phenylethylamine derivatives such as 3,4-dihydroxyphenylalanine, and their cyclisation products with aldehydes, i.e., 1,2,3,4-tetrahydroisoquinoline derivatives in blood samples. 1,2,3,4-Tetrahydroisoquinolines are considered to play an essential role as neurotoxic compounds in the pathomechanism of Parkinson's disease. We used reversed-phase high-performance liquid chromatography with ultraviolet and fluorescence detection for separation and identification. Ultrafiltration, protein precipitation and solid-phase extraction were investigated for purification of blood samples and enrichment of various compounds with a wide range of hydrophilicity and hydrophobicity. Protein precipitation by methanol and perchloric acid is a fast method to separate the analytes from the plasma matrix. A higher yield of the analytes is attained with prior addition of an alkylsulfonic acid giving a fine-grained precipitate. With the addition of ion pairing compounds into the sample it is possible to enrich not only lipophilic compounds such as norharman, tryptamine and melatonin, but also hydrophilic ones such as 3,4-dihydroxyphenylalanine by reversed-phase solid-phase extraction. Ultrafiltration is not useful as a screening method.
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Authors | P Pagel, R Schubert, H U Wolf |
Journal | Journal of chromatography. B, Biomedical sciences and applications
(J Chromatogr B Biomed Sci Appl)
Vol. 746
Issue 2
Pg. 283-95
(Sep 15 2000)
ISSN: 1387-2273 [Print] Netherlands |
PMID | 11076081
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Blood Proteins
- Isoquinolines
- Neurotoxins
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Topics |
- Blood Proteins
(chemistry, isolation & purification)
- Chemical Precipitation
- Chromatography, High Pressure Liquid
(methods)
- Humans
- Isoquinolines
(blood, chemistry)
- Neurotoxins
(blood, chemistry)
- Parkinson Disease
(blood)
- Spectrometry, Fluorescence
- Spectrophotometry, Ultraviolet
- Ultrafiltration
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