Abstract: A method for covalently bonding an analyte sensitive dye compound to an addition-cure silicone is disclosed. The method includes a first step of functionalizing the dye compound to provide a linker arm with an isolated multiple bond. A second step include hydrosilylating the functionalized dye with polymethylhydrosiloxane. The resulting compound is cross-linked with vinyl-terminated polysiloxane in a third and final step.

Abstract: The system for measuring the concentration of oxygen in a fluid sample which may also contain halothane includes a sensor having a matrix containing a first indicator dye which fluoresces at a known wavelength when irradiated with light of a specific wavelength and containing a second indicator dye which fluoresces at a different emission wavelength upon irradiation with light of a similar or different specific wavelength. The fluorescence of the first and second indicator dyes are quenched to a different degree by the presence of oxygen, but the fluorescence of the indicator dyes is quenched to the same degree by halothane. Means are provided for irradiating the indicator dyes in the matrix with the appropriate wavelengths of light, and means are provided for measuring the resultant intensity of fluorescence of the indicator dyes at the different wavelengths of fluorescence.

Abstract: A method of purifying an aromatic carboxylic acid halide, for example p-phenoxybenzoyl chloride, comprising the steps of: (a) adding an acidic catalyst, for example a molecular sieve, to the acid halide; (b) heating the resulting mixture of the acidic catalyst and the acid halide to a temperature of about 180.degree. C. to about 250.degree. C. for a period of at least 0.5 hours; (c) distilling the mixture to obtain acid halide substantially free of aldehyde and the halo derivative thereof. Optionally, a reactive aromatic compound may be added to the mixture of the acid halide and the acidic catalyst before the heating step. The process is particularly useful for providing aromatic acid halides of sufficient purity for preparing melt stable aromatic polyketones.