METHOD OF REVEALING AND ANALYZING TRACE QUANTITIES OF ORGANIC MOLECULES IN AIR ATMOSPHERE Russian patent published in 2002 - IPC

FIELD: analytical methods. SUBSTANCE: air flow containing trace quantities of organic explosive, narcotic, or physiologically active molecules is introduced at atmosphere pressure into closed or flow-type space containing cathode and supplementary collecting electrode. Cathode is constructed from material containing at least one oxide bronze of alkali metal and transition metal oxide expressed by formula R_xMe_nO_m wherein x = 0.1-1.2, R represents alkali metal, Me represents transition metal selected from: titanium, vanadium, niobium, tantalum, molybdenum, tungsten, and rhenium, O represents oxygen, compound Me_nO_m being one of bronze-forming oxides of metal Me. Cathode is heated to working temperature (within 50 to 500 C), potential drop between cathode and collector is imposed, and current of positively charged ions of secondary organic molecules is measured, said molecules being formed on the surface of cathode as a result of interaction of organic molecules with alkali metal atoms on the cathode surface under the air atmosphere conditions. To enhance sensitivity, additional voltage is imposed between working surface of cathode and its opposite surface. In order to extend class of analysis-suitable organic molecules and to increase analytical sensitivity, complex oxide bronze expressed by formula R1x