The use of recently described ionisation techniques for the rapid analysis of some common drugs and samples of biological origin

Three ionisation techniques that require no sample preparation or extraction prior to mass analysis have been used for the rapid analysis of pharmaceutical tablets and ointments. These methods were (i) the novel direct analysis in real time (DART), (ii) desorption electrospray ionisation (DESI), and (iii) desorption atmospheric pressure chemical ionisation (DAPCI). The performance of the three techniques was investigated for a number of common drugs. Significant differences between these approaches were observed. For compounds of moderate to low polarity DAPCI produced more effective ionisation. Accurate DESI and DAPCI tandem mass spectra were obtained and these greatly enhance the selectivity and information content of the experiment. The detection from human skin of the active ingredients from ointments is reported together with the detection of ibuprofen metabolites in human urine.