A question of balls and chains: The copolymerization of an achiral fullerene and an optically active phenylacetylene yields a helical polymer (see picture) where the pendant C60 groups adopt a predominant screw‐sense along the polymer backbone. The copolymer exhibits an induced circular dichroism in the fullerene chromophoric region.
Assay of alkaline phosphatase (ALP) in salmon egg cell cytoplasm was performed by size exclusion chromatography (SEC) with fluorescence detection of enzymatic activity and element-selective detection of zinc by ICP-MS, where 4-methylumbelliferyl phosphate (4-MUP) was used as the substrate for the enzymatic reaction of ALP. Two peaks were observed at retention times of ca. 21 and 27 min in the fluorescence-detected SEC chromatogram for salmon egg cell cytoplasm diluted 10-fold with 0.1 M Tris-HNO3 buffer solution, corresponding to the molecular weights (MWs) of ≥300 and 100 kDa, respectively. On the other hand, in the 66Zn-detected chromatogram for the same sample, a broad peak with a shoulder on the side of longer retention time was observed at ca. 21 min (MW≥300 kDa). When salmon egg cell cytoplasm was diluted 10-fold with pure water or 0.01 M Tris-HNO3 buffer solution, precipitation occurred. The supernatant obtained after filtration produced only one clear peak at a retention time of ca. 27 min in the fluorescence-detected chromatogram, at which the peak corresponding to zinc was also observed in the Zn-detected chromatogram. Therefore, the peak near 27 min was assigned to hydrophilic ALP in the salmon egg cell cytoplasm. Furthermore, the concentration of hydrophilic ALP (MW ca. 100 kDa) in the salmon egg cell cytoplasm was about 350 ng g−1, which was determined as an E. coli ALP-equivalent concentration by fluorescence intensity measurements.
The speciation of diverse elements in salmon egg cell cytoplasm was performed by a surfactant-mediated HPLC/ICP-MS hyphenated system.In the present experiment, an ODS column coated with CHAPS (3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate), which is a zwitterionic bile acid derivative, was employed as a surfactant-mediated separation column, and ICP-MS was used as an element-selective detector. The present surfactantmediated HPLC allowed us to separate large and small molecules within 10 min; large molecules, such as proteins, were eluted within 2.5 min, while small molecules were eluted after 2.5 min, but within 10 min. In the present experiment, Fe, Cu, and Zn in egg cell cytoplasm were observed mostly in species with large molecular weights, indicating that these elements are contained as metalloproteins or metalloenzymes in egg cell cytoplasm. On the contrary, it was found that P, S, Mo, and halogens in egg cell cytoplasm were contained as small molecules or inorganic ions. The major species of P in egg cell cytoplasm was identified as the phosphate ion (PO4 3-). Molybdenum, Cl, and Br in egg cell cytoplasm were molybdate (MoO4 2-), chloride (Cl -), and bromide (Br -) ions, respectively.
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