| OCR Text |
Show 67 and the dried extracts were then reconstituted in approximately 401 ethyl acetate prior to analysis by gas chromatography-mass spectrometry (GC-MS). Hair samples were digested and analyzed for PCP in the manner described in previous chapters. After the addition of PCP-ds (internal standard) to 10 mg of hair, samples were completely solubilized (digested) overnight with 1 N NaOH at 30°C. Solubilized hair samples were then prepared and extracted as described above. Electron ionization mass spectrometric analysis of reconstituted extracts was performed on a Finnigan Magnum ™ ion trap mass spectrometer coupled to a Varian 3400 gas chromatograph equipped with a Varian 1075 injector and a J & W DB-5 MS capillary column (30 m x 0.25 mm i.d., 0.25 urn film thickness). Ultra-high purity helium was used as a carrier gas with a head pressure of 9 psi; 1 ul of reconstituted extract was injected while the instrument was in the splitless mode. The column temperature was held at 125°C for 0.5 min, increased to 27YC at 20o/min then held at 27YC for 0.5 min. The injector was maintained at 200°C, the transfer line was maintained at 250°C and the manifold was maintained at 20(rC. The filament emission current was 12 A; the electron multiplier voltage was 1700 V. The electron ionization mode was used with the automatic gain control on and 300 ms ion time. GC-MS analysis of the mass range 175275 amu was performed at 0.6 s/scan for all extracts. PCP was quantitated in hair or plasma samples from daily calibration curves prepared from drug free hair or plasma (10 mg or 1 ml) fortified with PCP over the range of 0.1 ng/mg to 50 ng/mg (hair) or 1 ng/ml to 500 ng/ml (plasma) and extracted and analyzed as described above. Mouse plasma (10 ul) was analyzed for PCP by RIA according to the kit manufacturer's instructions. A calibration curve ranging from 0 ng/ml to 250 ng/ml was included for the quantitation of PCP in the plasma samples. Quantitation of PCP was determined by generating a log/logit transformed calibration curve of concentration verses CPM. Unknown plasma concentrations were calculated using the line equation generated |
