Patent ID: 8551322

Claim:
A method of measuring an amount of a gaseous species in a sample, the method comprising contacting the sample with a sensor comprising a polysiloxane membrane; wherein: the polysiloxane membrane comprises one or more silicon atoms covalently attached to an alkyl group and one or more silicon atoms covalently attached to a fluorinated alkyl group, wherein the polysiloxane membrane is a condensation product of a silane mixture comprising an alkyl alkoxysilane and a fluorosilane, wherein the fluorosilane comprises a structure having a formula: F 3 C—(CF 2 ) m —(CH 2 ) n —Si(X) p (Y) 3-p wherein: m is 0 to 15; n is 1 to 5; p is 1, 2, or 3; each X is independently selected from the group consisting of alkoxy, aryloxy, aralkoxy, hydroxyl, and halo; and each Y is independently selected from the group consisting of H, alkyl, aryl, and aralkyl; and the polysiloxane membrane selectively allows the gaseous species in the sample to be measured by the sensor.