|Budget Amount *help
¥12,400,000 (Direct Cost: ¥12,400,000)
Fiscal Year 2001: ¥2,500,000 (Direct Cost: ¥2,500,000)
Fiscal Year 2000: ¥2,900,000 (Direct Cost: ¥2,900,000)
Fiscal Year 1999: ¥7,000,000 (Direct Cost: ¥7,000,000)
This research has been performed, being directed to developing novel electroanalytical media for medicinal and environmental pharmaceutical sciences, and has afforded the following interesting results.
1. Anodization in triethylene glycol containing CH_3CH_2SO_3Na at 2.0 V vs. Ag/AgCl at the expense of 3 C followed by the chemical treatment with an amino compound containing an electrochemical redox group such as 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO) and catechol in DMF in the presence of DCC or WSC was shown to provide a feasible and reproducible access to glassy carbon (GC) electrodes with catalytic ability useful for bio-analytical chemistry.
2. When GC electrodes anodized in triethylene glycol containing HOCH_2CH_2SO_3Na at 2.0 V vs. Ag/AgCl are subjected to electrochemical measurements in aqueous media, hydrophobic and/or ionophoric interactions are likely to dominate permeability of analytes into the surface membrane of the modified electrode. Thus, it was demonstrated that
this surface modification induces electrochemical discrimination between various catecholamines depending on their degree of hydrophobicity as well as on their charged situations
3. It was found that aliphatic primary amines, which are notorious for environmental toxicity, can be analyzed by HPLC with electrochemical detector (ECD-HPLC) by pre-column derivatization to methyl alkyl thioureas by reaction with methyl isothiocyanate. Thus, this methodology was capitalized for sensitive analysis of propyl, butyl and pentyl amines by ECD-HPLC at reverse-phase mode with mobile phase of markedly high water-contents such as 95:5 H_2O:CH_3CN.
4. It was demonstrated that polyamines as a biologically important class of compounds are amenable to electrochemical detection with a flow system after derivatization with ethyl isothiocyanate. Thus, highly sensitive ECD-HPLC for a mixture of putrescine, cadaverine, tyramine, 1,6-diaminohexane, spermidine, phenethylamine, tryptamine and spermine is achieved under quite practical conditions using 20:15:60 CH_3CN-THF-H_2O as the mobile phase and a ODS column. Less