An investigation and identification of polysaccharides isolated from archeological specimens
SummaryPolymeric compounds have been isolated from archeological specimens (fragments of Central Asian paintings of the 2nd-19th centuries). A comparison of their IR spectra with the spectra of plant gums has shown that they are polysaccharides which have remained undestroyed for up to 1800 yr. In some cases it has been possible from the IR spectra and composition of the extracted polysaccharides to provisionally identify sourcherry or apricot gum, of which these polysaccharides were components.
Thin-layer chromatographic analysis of sugar mixtures
Abstract Some general remarks are made concerning the difficulties experienced in the quantitative determination of the composition of complex sugar mixtures in solution. The application of thin-layer chromatography to this analytical problem is discussed. A technique for obtaining a satisfactory separation of nine to ten sugars has been worked out. Methods of determining reducing sugars and keto-sugars in amounts of 0 to 100 μg are mentioned, as well as a technique for removing the sugar-containing area from the thin-layer plate. Figures illustrating the quantitative aspects of the method are given.
A rapid method for locating and eluting radioactive streaks on an electropherogram or a chromatogram.
Abstract The design, construction and operation of a scanner to rapidly locate radioactive streaks on an electropherogram is described. Using this scanner and a rapid elution technique one can isolate unstable compounds from wet electropherograms in about 6 min while maintaining the products at 0°. The performance and limitations of the scanner are described. It will detect about 30 disintegrations per minute of 32 P activity per mm 2 and will resolve radioactive spots separated by as little as 2mm. Using the scanner we have been able to succesfully isolate a number of unstable photoproducts from [ 32 P]CpC and study their properties. The scanner can also detect photoproducts containing a 14 C label, but detection of 3 H will involve modifications involving use of a windowless counter.