Direct injection high-performance liquid chromatographic assay of morphine with electrochemical detection, a polymeric column and an alkaline eluent
| Autor: | Mario Marigo, G. Carli, R. Dorizzi, Franco Tagliaro |
|---|---|
| Rok vydání: | 1990 |
| Předmět: |
Chromatography
Morphine Elution Organic Chemistry General Medicine morphine HPLC electrochemical detection Phosphate Biochemistry High-performance liquid chromatography Blood proteins Reference electrode Amperometry Analytical Chemistry chemistry.chemical_compound Column chromatography chemistry Ionization Electrochemistry Humans Chromatography High Pressure Liquid |
| Zdroj: | Journal of Chromatography A. 507:253-258 |
| ISSN: | 0021-9673 |
| DOI: | 10.1016/s0021-9673(01)84202-3 |
| Popis: | A simple method is described for the direct determination of morphine in untreated plasma or serum, using reversed-phase high-performance liquid chromatography with amperometric electrochemical detection. A basic eluent [0.05 mol/l phosphate buffer-isopropanol-tetrahydrofuran (88:10:2) (pH 9.5)] allows both reversed-phase chromatography of morphine under ionization control conditions and its detectability at an unprotected thin-layer glassy carbon electrode at a potential of 350 mV (vs. an Ag/AgCl reference electrode). In addition, the alkaline mobile phase promotes the ionization of serum proteins, which, being poorly retained by the hydrophobic column packing [poly(styrene-divinylbenzene) copolymer], elute early in the chromatogram, leaving a clean baseline. Up to 50 microliters of simply filtered plasma can be injected. The absolute limit of detection is 0.75 ng on-column. No interferences were observed from more than 80 opiate and non-opiate drugs. The intra- and inter-assay relative standard deviations (n = 5) were 3.2 and 6.6%, respectively, at a morphine concentration of 100 ng/ml in plasma and 0.09 and 4.2%, respectively, at the level of 500 ng/ml. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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