Bradford Protein Assay Spectrophotometry. Includes spectrophotometry information and the Bradford protein assay: A spectrophotometer or colorimeter makes use of the transmission of light through a solution to determine the concentration of a solute within the solution. A spectrophtometer differs from a colorimeter in the manner in which light is separated into its component wavelengths. A spectrophotometer uses a prism to separate light and a colorimeter uses filters. - [Read Bradford Protein Assay Spectrophotometry]