An improved chemical method for fecal occult blood testing

ObjectiveTo establish an improved chemical method for the determination of fecal occult blood test(FOBT).MethodsA dry FOBT reagent was prepared using 3,3′,5,5′-tetramethylbenzidine(TMB) as main matieral.ResultsThe range of detection of hemoglobin(Hb) was 5-10 000 μg/mL.Digestion of Hb by enzymes in gastrointestinal(GI) tract did not effect the FOBT detection with improved method.High concentration of Hb,which showed negative result immunological FOBT by hook effect,and had no influence in chemical FOBT.ConclusionsChemical methods are need to be used in FOBT.The improved TMB method is better than traditional chamical methods.It is rapid,simple and increases the sensitivity and the detection range.In FOBT chemical method should be used in addition of immunological method for avoiding false negative result.