a diagnostic kit is disclosed for the detection of hemoglobin , myoglobin , ferritin , or the like substances having peroxidase - like activity in different mixtures of biological origin , such as fecal blood in toilet bowl , occult blood in the breath of internally bleeding horses , or myoglobin in the urine of severely muscle damaged victims . the kit includes , in an air , moisture , and light proof package , an inert water insoluble matrix , such as a sheet of paper , which has an area where a chemical composition containing a water soluble polymer , or polymers , is deposited in at least two separate steps of thin film coating , for the detection of the above substances . the composition further includes one or more oxygen donors , one or more organic peroxides or other suitable oxidizing agents , and a leuco - dye which gives a colored oxidation product when it is oxidized by the oxidizing agents with the hemoglobin or like substance acting as the catalyst . also disclosed is a method of making the test device for use in the kit . also disclosed is a method of making the test device for use in the kit .