Preliminary wash/decontamination

Initial studies performed during the late 1970s and early 1980s revealed the presence of benzoylecgonine (cocaine metabolite) and morphine (heroin metabolite) in hair. Since then, fiu-ther studies of hair analysis have identified additional cocaine analytes and opioids. The aim of this chapter is to provide a review of the analytical techniques utilized in hair analysis, including preliminary wash/decontamination procedures, methods of analyte isolation and pmification, and analysis of the hair extracts. In addition, this chapter will present research findings. 

The uptake of cocaine to hair after preliminary exposure to various acidic and basic solutions is shown in Figure 10. Three sets of experiments were performed. In the first experiment, hair was exposed to base (0.1 M sodium carbonate, pH 12) for 3 h and then washed extensively with water rmtil the water was neutral. This was then followed by two phosphate buffer rinses at pH 5.3 for 10-min periods. The hair was then exposed to 5 pg/mL of cocaine, containing a radioactive tracer, in phosphate buffer at pH 5.3 for 1 h. After exposure the excess cocaine was removed with three water rinses of 10 min each and the hair was dried. Then the hair was decontaminated with ethanol and six phosphate washes, digested, and the cocaine concentration determined by scintillation counting as per previously described procedures. Approximately twice as much cocaine was incorporated into the hair pretreated by exposure to base as compared to hair not subjected to any pretreatment. In the second experiment, hair was pretreated with 0.1 M HCl, then treated as in the first experiment. In this case approximately one sixth as much cocaine was incorporated as the control. In the third experiment, hair was pretreated with 5% acetic add and treated as in the... 

Analysis of the final Am02 product is shown in Table VI. A1 and Mg were below the detectable limits for these elements. The product met specifications of >95% Am02 with less than 0.5% Pu and less than 1% of any other single contaminant. The results of the preliminary lab scale extraction chromatography tests are shown in Table VII. Again, in spite of some analytical problems, it is evident that americium was decontaminated from aluminum and magnesium. A 7M HNO3 wash step is assumed to account for the americium loss. 

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