A New Ionization Method for Organic Compounds.-Liquid Ionization at Atmospheric Pressure Utilizing Penning Effect and Chemical Ionization

Atmospheric pressure chemical ionization source. 1. Ionization of compounds in the gas phase.

A novel chemical ionization source for organic mass spectrometry is introduced. This new source uses a glow discharge in the flowing afterglow mode for the generation of excited species and ions. The direct-current gas discharge is operated in helium at atmospheric pressure; typical operating voltages and currents are around 500 V and 25 mA, respectively. The species generated by this atmospher...

The theory of Penning ionization.

Determination of Salvinorin A in body fluids by high performance liquid chromatography-atmospheric pressure chemical ionization.

Salvinorin A was quantitated in human and rhesus monkey plasma, rhesus monkey cerebrospinal fluid, and human urine by negative ion LC-MS/APCI. The method for Salvinorin A has been fully validated, the LLOQ using FDA guidelines is 2 ng/mL for 0.5 mL plasma samples. The linear range was from 2 to 1000 ng/mL. Several derivatives in the Salvinorin family can also be analyzed by this method; d(3)-Sa...

Occurrence of radical molecular ions in atmospheric pressure chemical ionization mass spectra of heterocyclic compounds.

It is well-known that the use of atmospheric pressure ionization (API) techniques, such as electrospray ionization (ESI) or atmospheric pressure chemical ionization (APCI), is associated with the formation of even-electron ions,1 for example, protonated molecules [M C H]C, adducts with alkali metal ions [M C Na]C and [M C K]C, adducts with ammonium ions [M C NH4]C in the positive-ion mode and d...

Charge Exchange Reaction in Dopant-Assisted Atmospheric Pressure Chemical Ionization and Atmospheric Pressure Photoionization.

The efficiencies of charge exchange reaction in dopant-assisted atmospheric pressure chemical ionization (DA-APCI) and dopant-assisted atmospheric pressure photoionization (DA-APPI) mass spectrometry (MS) were compared by flow injection analysis. Fourteen individual compounds and a commercial mixture of 16 polycyclic aromatic hydrocarbons were chosen as model analytes to cover a wide range of p...