The present invention relates to a chemical compound or a salt or solvate thereof being an 1-amino-phenazine derivative and to uses thereof. The present invention further relates to a chemistry matrix and to a test element comprising the aforesaid chemical compound. Moreover, the present invention relates to a method for determining the amount of an analyte in a sample, comprising contacting said sample with a chemistry matrix according to the present invention, estimating the amount of electrons liberated or consumed by the chemistry matrix in the presence of said liquid sample, and thereby determining the amount of an analyte in a liquid sample.