Status and use of HPLC-DAD/APCI-MS and direct flame sampling/APCI-MS for fullerenes and PAH research. First annual technical report for instrumentation grant, Project period 1 August 1992--31 July 1994

The PE/Sciex APCI/LC-MS equipment consists of a high performance liquid chromatograph (HPLC) with diode array spectrophotometric detector (DAD) interfaced to an atmospheric pressure ionizer with a single quadrupole mass spectrometer (MS) through a heated nebulizer. The interface between the HPLC and the MS is designed to minimize thermal input to the HPLC eluents and is of great importance for the authors intended application. Ionization occurs in a unique fashion at atmospheric pressure using a chemical ionization source (APCI). The equipment is being used for the identification and quantification of flame-generated fullerenes and polycyclic aromatic hydrocarbons (PAH). The mode of operation of this instrument is as follows: (1) complex mixtures are separated by the HPLC; (2) UV spectra of separated components are obtained by the diode array detector (DAD) as they elute from the HPLC; (3) components undergo mild ionization in the APCI source; and, (4) mass spectra are acquired by the mass spectrometer