Hand-held amperometric sensor for saliva and other oral fluid-based diagnostics

摘要

A new hand-held amperometric sensor fo rmonitoring of saliva and other oral fluid-based components is described.The amperometric sensor includes a flow through amperometric detector coupled with a micropipette,and an electronic block which consists of an amplifier,peak detector,microprocessor and display.All operatons,such as sample injec tion,electrochemcial detection and data processing are accomplished using only one action,by pressing the plunger of the micropipette.The instrument has been applied for assay of aslivary of salivary peroxidase,hman lutinizin ghormone and human chorionic gonadotropin.The low detection limit of peroxidase is 0.5 ng/ml (defind as the concentration which gives a signal with S/N >2).The respone time of the sensor is 1-3S.The linear dynamic range of the hormones is from 1.0 to 80 mUI/ml.The life time of the hand-heldj amperometric device without regeneration of the electrode surface is 12 months.The sensor has the potential as a tool for noninvasive physiological studies and diagnostic strategies.