The invention relates to stannous halide stabilized and/or enhanced alkaline solutions to be used in combination with colorimetric, luminescent and fluorescent assays. The buffered solutions stabilize hydrogen peroxide at a pH greater than 7.0 and preferably greater than 9.0. By stabilizing and/or enhancing hydrogen peroxide in the buffer system, the compositions used in such assays may have a higher shelf-life and provide enhanced detection of the subject analyte.
