CsCl standard deviations

Compositional patterns were called genome phenotypes (Bernard and Bernard , 1986a), because they are different in different vertebrate classes (see also Part 4). It should be stressed that, until the work of Thiery et al. (1976), the common belief was that, while DNA composition varied greatly among bacteria, animal species had a rather similar DNA composition (Kit, 1960). Although some small variations in modal buoyant densities and standard deviation of CsCl profiles had been detected in vertebrate DNAs, these could be due to different methylation levels (Kit, 1962). 

Quantitative determination of the monoisotopic element cesium can only be performed by using a radioactive isotope or a different alkali element as an internal standard or by establishing a calibration curve as an external standard. A plot of such a curve is given in Fig. 13 for [Cs]" . For measurements, a number of standard solutions of CsCl in CCI4 are prepared and analyzed. The resultant values are displayed with an error of 22% corresponding to 2a (a = standard deviation). 

Fig. 13. Calibration curve for quantitative determination of [Cs]" correlating the sample amount with the peak area of the evaporation profile obtained by FDMS and sin e ion monitoring of m/z 133. For these measurements, a number of standard solutions of CsCl in carbon tetrachloride were prepared and analyzed. The values of the analyses are displayed with an error of 20% corresponding to 2

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