Iontophoretic sampling device and method

摘要

An iontophoresis apparatus for the transdermal monitoring of a target substance comprising: first and second collection reservoirs, the first collection reservoir comprising a first ionically conductive medium (111) and the second collection reservoir comprising a second ionically conductive medium (113); a first iontophoresis electrode (162) in contact with the first conductive medium (111) and a second iontophoresis electrode (164) in contact with the second conductive medium (113); a sensor for detecting the target substance contained within at least one conductive medium (111, 113); and an iontophoretic power source (224). The conductive medium (111, 113) is either an ionically conductive hydrogel or a wicking material containing an ionically conductive medium. The invention also includes a collection reservoir for use with an iontophoresis apparatus for the transdermal monitoring of a target substance, the collection reservoir comprising an ionically conductive hydrogel having a pH in the range of from about 4.0 to about 10.0 and an enzyme reactive with the target substance. The invention also includes a method for using the transdermal monitoring apparatus. In particular, the invention is a method for continuous in vivo monitoring of the blood glucose level of a patient comprising the following steps: (a) placing a collection reservoir on a collection site on a tissue surface of the patient; (b) applying electrical energy to the collection site to move glucose or a glucose metabolite into the collection reservoir; (c) analyzing the collection reservoir for concentration of glucose or glucose metabolite; (d) correlating the concentration determined in step (c) with blood glucose level; and (e) performing steps (a)-(d) substantially continuously.