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Three saponins were extracted and isolated from starfish by reversed-phase high performance liquid chromatography (HPLC), and analyzed by fast atom bombardment mass spectrometry (FAB-MS). Their molecular weight information could be obtained by the presence of abundant [M+Na]+ ions and weak [M+H]+ ions in FAB-MS spectra. Moreover, high resolution mass measurements of their [M+Na]+ ions were performed at the resolution of 10000 to elucidate the element composition of extracted saponins. The collision-induced dissociation (CID) of sodium-adducted molecules [M+Na]+ yielded diverse product ions via dissociated processes. In the collision-induced dissociation (CID)-MS/MS analysis of [M+Na]+ ion, the sulfate-containing saponins produced characteristic ions such as SO4Na+, [NaHSO4+Na]+, [M+Na-sugar]+ and [M+Na-2sugar]+ ions, whereas the sulfate-free compound showed characteristic ions produced by cleavage of sugar moiety and side chain of aglycone. The fragmentation patterns could provide information on the linkage position of sugar groups in aglycone and sulfate groups.

The photodegradation of pentachlorophenol in water was examined with a high-pressure mercury lamp. A number of photodegradation products of pentachlorophenol, such as less-chlorinated phenols through reductive dechlorination, and catechol and trihydroxylated products via the addition of hydroxyl radicals, were observed as major products. Moreover, polychlorinated biphenylethers, hydroxylated polychlorobiphenylethers and polychlorinated dibenzo-p-dioxins as minor products were also formed by dimerization process during the photolysis of pentachlorophenol. These compounds were identified by gas chromatography-mass spectrometry. The degradation rate of PCP in water was measured against the UV-irradiation time. After the irradiation for 15 min, 75% of PCP was converted into a number of products through reductive dechlorination and oxidation. On the basis of the identified products, the photodegradation pathways of PCP under UV irradiation were proposed.

The photodegradation of DDT in water was examined with a high-pressure mercury lamp. A total of 17 photodegradation products of DDT including DDD, DDE and DDMU were identified by gas chromatography-mass spectrometry (GC-MS). Mass spectrometric analyses were done with electron impact (EI), methane positive chemical ionization (PCI) and electron capture negative ion chemical ionization (ENCI). The degradation rate of DDT in the presence of acetone was measured against the irradiation time. After the irradiation for 10min, 80% of DDT was converted into a number of products, including DDD, DDE, DDMU and dichlorobenzophenone, through reductive dechlorination, oxidation, isomerization and chlorination. On the basis of the identified products, the photodegradation pathways of DDT are proposed.

The sensitization of Eu(III) ion emission in tetrahydrofuran by copolymers of styrene-maleic anhydride, styrene-maleic acid(PSMA), and europium salt of PSMA(PSMA-Eu) was studied. When excited at 260 nm in the presence of PSMA, the emission of Eu(III) at 618 nm exhibited large enhancement compared with that in the absence of PSMA. The enhancement was even greater for PSMA-Eu and accompanied by the decrease in monomer and excimer emission of polymers, suggesting that energy is transferred from the excited polymer to Eu(III) ions