Substantial evidence laboratory data

Neither the effect of the used instrumentation (the pumps, columns and detectors) nor the software applied for the data processing was evaluated from the point of view of accuracy of results. It is evident, that the worldwide standardization of both measurement and data processing are badly needed in SEC. At least the experimental conditions within the same laboratory should be kept constant. This may prove, however, difficult as the detectability of various samples differs substantially and the Cj/Vj is to be adjusted for each kind of sample. 

CP/MAS NMR, with C-13, P-31, and a variety of spin-one-half nuclides can yield high-resolution NMR data that provide badly needed bridges between the liquid and solid states. These bridges can be used to estimate the extent to which diffraction-determined structural results on crystalline solids can be extrapolated into the liquid state. A substantial effort in this direction is underway in our laboratory. The potential for CP/MAS NMR in characterizing polymer-supported catalysts is also evident. 

The evidence from this laboratory and from others reviewed in this chapter reinforces and extends the serious concern that external contamination of hair by drugs of abuse can easily occur. Any interpretation of hair analysis data should consider the prospect that the sample could have been externally contaminated. The pharmacokinetics of the incorporation of drugs into many tissues has been well elaborated. However, substantial additional information on the mechanisms for incorporation of drugs into hair, the decontamination of hair, the differentiation between exposure to exogenous and endogenous drugs, and the meaning of the presence of metabolites in the hair are needed before hair analysis can be employed in many forensic applications. 

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