The quantitative determination of drugs in blood becomes more and more important. One reason is that threshold values for driving under the influence of drugs are in the discussion. Several points e.g. the differences between blood and serum or active and inactive stereoisomeres must be taken into consideration. The available methods are able to determine drugs with a SD of about 10 percent which is much higher than for the determination of alcohol in blood. It is additionally necessary to lower the limits of detection especially for THC into a range of about 0.5ng per ml with a signal to noise ratio of more than five at this concentration. It is not necessary to prescribed specific methods but methods but internal and external quality control programs are essential elements in quantitative determination of drugs. (A)
Samenvatting