Abstract: A test device for determining the presence of a constituent in a sample, and a method for making it are disclosed. The test device comprises reactants (e.g. reagents, enzymes, etc.) incorporated with a carrier matrix such that when the device is wetted with a test sample, the reactants and the constituent react to produce a detectable response. The reactants are positioned separately from each other on the matrix in substantially, discrete, non-contacting areas. Hence, reactants are maintained substantially separate from each other until the test device is wetted with the sample.

Abstract: In processes for measuring glycerides in a fluid, which processes require initial conversion thereof to glycerol, this conversion is achieved according to an improved and simplified saponifying reaction in which a reaction temperature between 35.degree. and 40.degree. C. is used.