Research on colloidal gold method of fecal occult blood testing in simulating gastrointestinal hemorrhage

Objective To study the result of colloidal gold method(GM) of fecal occult blood testing with hypo-concentrations of Hb which was digested by physiological concentration of acid,pepsin and trypsin.Methods(1)To prepare the certain concentration gradient of Hb,test and confirm the sensitivity of colloidal gold OB test strips.(2)The certain concentration gradient of Hb was mixed with physiological concentration of acid,pepsin and trypsin respectively,tested with colloidal gold of OB test strips after incubation at different times.Results(1)The sensitivity of colloidal gold of OB test strips was 0.1 μg/mL.(2)After incubated,different concentrations of Hb were digested fully by pepsin at 30 min and by trypsin at 1.5h.(3)The physiological concentration range of different concentrations of trypsin had the same time on digesting the same level of hypo-concentrations of Hb and the result of the positive extent was decreasing gradually and was negative finally.Conclusion(1)The sensitivity of colloidal gold of OB test strips produced by Aicon Bio-Technology Co.is 0.1 μg/mL.(2)The different concentrations of hypo-concentrations Hb are digested out respectively by the physiological concentration range of acid,pepsin and trypsin in imulating gastrointestinal hemorrhage,which causes the test result of colloidal gold method of fecal occult blood testing negative.