A Glucose Monitoring System With Remote Data Access.

A cost-effective portable glucose monitoring system with remote data access based on a novel e-oscilloscope was developed using a glucose biofuel cell and a capacitor circuit interfaced to an ESP8266 microcontroller programmed to convert the charge/discharge rates of the capacitor functioning as a transducer. The capacitor charge/discharge rates were converted into glucose concentration readings that is monitored remotely. The glucose monitoring system comprise a glucose biofuel cell, a charge pump circuit, a capacitor and an ESP microcontroller. The anode was fabricated by modifying a gold microwire with nanoporous colloidal platinum (Au-co-Pt) and the cathode was constructed using a mesh dense network of multiwalled carbon nanotubes modified with bilirubin oxidase, respectively. The glucose monitoring system showed sensitivity of 1.18 Hz/mM · cm2 with a correlation coefficient of 0.9939 with increasing glucose concentration from 1 mM to 25 mM. In addition, the glucose monitoring system exhibited optimal operation at a pH of 7.4 and 37 °C, which is ideal for physiological glucose monitoring.

A Fully-Flexible Solution-Processed Autonomous Glucose Indicator.

We present the first demonstration of a fully-flexible, self-powered glucose indicator system that synergizes two flexible electronic technologies: a flexible self-powering unit in the form of a biofuel cell, with a flexible electronic device - a circuit-board decal fabricated with biocompatible microbial nanocellulose. Our proof-of-concept device, comprising an enzymatic glucose fuel cell, glucose sensor and a LED indicator, does not require additional electronic equipment for detection or verification; and the entire structure collapses into a microns-thin, self-adhering, single-centimeter-square decal, weighing less than 40 mg. The flexible glucose indicator system continuously operates a light emitting diode (LED) through a capacitive charge/discharge cycle, which is directly correlated to the glucose concentration. Our indicator was shown to operate at high sensitivity within a linear glucose concentration range of 1 mM-45 mM glucose continuously, achieving a 1.8 VDC output from a flexible indicator system that deliver sufficient power to drive an LED circuit. Importantly, the results presented provide a basis upon which further development of indicator systems with biocompatible diffusing polymers to act as buffering diffusion barriers, thereby allowing them to be potentially useful for low-cost, direct-line-of-sight applications in medicine, husbandry, agriculture, and the food and beverage industries.