Simultaneous transdermal extraction of glucose and lactate from human subjects by reverse iontophoresis

Abstract

This study investigated the possibility of simultaneously extracting glucose and lactate from human subjects, at the same skin location, using transdermal reverse iontophoresis. Transdermal monitoring using iontophoresis is made possible by the skin's permeability to small molecules and the nanoporous and microporous nature of the structure of skin. The study was intended to provide information which could be used to develop a full, biosensor-based, monitoring system for multiple parameters from transdermal extraction. As a precursor to the human study, in vitro reverse iontophoresis experiments were performed in an artifi cial skin system to establish the optimum current waveforms to be applied during iontophoresis. In the human study, a bipolar DC current waveform (with reversal of the electrode current direction every 15 minutes) was applied to ten healthy volunteers via skin electrodes and utilized for simultaneous glucose and lactate transdermal extraction at an applied current density of 300 µA/cm 2 . Glucose and lactate were successfully extracted through each subject's skin into the conducting gel that formed part of each iontophoresis electrode. The results suggest that it will be possible to noninvasively and simultaneously monitor glucose and lactate levels in patients using this approach and this could have future applications in diagnostic monitoring for a variety of medical conditions.

Saliva-Based Biosensors: Noninvasive Monitoring Tool for Clinical Diagnostics

“…Hence, it is important to monitor capillary blood lactate (CBL) concentration, especially among patients in intensive care units and operating rooms as lactic acidosis can lead to muscle damage that may result in heart attack [ 36 ]. It is also essential to measure CBL levels among diabetics due to the close metabolic relationship between glucose and lactate [ 36 , 37 ]. Besides that, analysis of CBL concentration is of high interest in sports medicine for athletes to tailor their training in order to optimise their performance [ 38 , 39 ].…”