FSM-type mesoporous silica modified with various diols was utilized as an inorganic medium for immobilizing chlorophyll a (Chl a) without denaturation. The energy transfer from Chl b to Chl a in the mesopores was also observed for the first time. Silanol groups on the mesoporous silica were esterified with diols, and this was confirmed by 13C MAS NMR, IR, N2 adsorption, and elemental analysis. The suppression of the pigment degradation in modified FSM was confirmed by both visible absorption spectroscopy of the FSM/Chl compounds and the analysis of the extracts from FSM/Chl by high-performance liquid chromatography. The fluorescence emission bands of Chl a and Chl b in FSM modified with 1,6-hexanediol appeared at 672 and 654 nm, respectively. In the FSM/Chl containing both Chl a and Chl b, the emission band due to Chl b was decreased whereas the band due to Chl a was increased. This is in sharp contrast to the emission spectrum of an acetone solution containing both of Chls, implying energy transfer from Chl b to Chl a in modified mesoporous silica.
|Number of pages||8|
|Journal||Chemistry of Materials|
|Publication status||Published - 2001 Sept 21|
ASJC Scopus subject areas
- Chemical Engineering(all)
- Materials Chemistry