Abstract In this work, a low power microcontroller-based near field communication (NFC) interfaced with a flexible abiotic glucose hybrid fuel cell is designed to function as a battery-less glucose sensor. The abiotic glucose fuel cell is fabricated by depositing colloidal platinum (co–Pt) on the anodic region and silver oxide nanoparticles-multiwalled carbon nanotubes (Ag 2 O-MWCNTs) composite on the cathodic region. The electrochemical behavior is characterized using cyclic voltammetry and chronoamperometry. This glucose hybrid fuel cell generated an open circuit voltage of 0.46 V, short circuit current density of 0.444 mA/cm 2 , and maximum power density of 0.062 mW/cm 2 at 0.26 V in the presence of 7 mM physiologic glucose. Upon device integration of the abiotic glucose hybrid fuel cell with the NFC module, the data from the glucose monitoring system is successfully transmitted to an android application for visualization at the user interface. The cell voltage correlated (r 2 = 0.989) with glucose concentration (up to 19 mM) with a sensitivity of 13.9 mV/mM•cm 2 .
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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.
more » « less- Award ID(s):
- 1921364
- NSF-PAR ID:
- 10153392
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 9
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract A hybrid biofuel cell (HBFC) is explored as a low-cost alternative to abiotic and enzymatic biofuel cells. Here the HBFC provides an enzymeless approach for the fabrication of the anodic electrode while employing an enzymatic approach for the fabrication of the cathodic electrode to develop energy harvesting platform to power bioelectronic devices. The anode employed 250 μm braided gold wire modified with colloidal platinum (Au-co-Pt) and bilirubin oxidase (BODx) modified gold coated Buckypaper (BP-Au-BODx) cathode. The functionalization of the gold coated multi-walled carbon nanotube (MWCNT) structures of the BP electrodes is achieved by 3-mercaptopropionic acid surface modification to possess negatively charged carboxylic groups and subsequently followed by EDC/Sulfo-NHS (1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-Hydroxysulfosuccinimide) crosslinking with BODx. The integration of the BODx and gold coated MWCNTs is evaluated for bioelectrocatalytic activity. The Au-co-Pt and BP-Au-BODx exhibited excellent electrocatalytic activity towards glucose oxidation with a linear dynamic range up to 20 mM glucose and molecular oxygen reduction, respectively. The HBFC demonstrated excellent performance with the largest open circuit voltages of 0.735 V and power density of 46.31 μW/cm2in 3 mM glucose. In addition, the HBFC operating on 3 mM glucose exhibited excellent uninterrupted operational stability while continuously powering a small electronic device. These results provide great opportunities for implementing this simple but efficient HBFC to harvest the biochemical energy of target fuel(s) in diverse medical and environmental applications.
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A novel electrochemical glucose sensor was created for a simple but semiquantitative visual screening of specific glucose concentrations in urine. This noninvasive glucose biosensor integrated a disposable, paper-based sensing strip and a simple amplifier circuit with a visual readout. The paper strip consisted of five enzyme-activated electrodes. Each electrode was connected to a specific indicator circuit that triggered a light-emitting diode (LED) when a predefined glucose concentration was reached. The device features (1) low-cost, disposable, paper-based glucose oxidase (GOx)/poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) sensing electrodes, (2) simple signal amplification, and (3) on-site, rapid, and visual detection. The sensor generated reliable, discrete visual responses to determine five glucose levels (1, 2, 3, 4, and higher than 4 mM) in urine in less than 2 min. This innovative approach will provide a simple but powerful glucose sensing paradigm for use in POC diagnostics.
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A glucose biofuel cell on a flexible bacterial nanocellulose film was prepared. The bioelectrodes were printed using gold ink as the conductive material. The anode was modified with colloidal platinum for the oxidation of glucose. The cathode was modified with a nanocomposite comprising gold nanoparticles (AuNPs) and silver oxide (Ag2O) nanoparticles. The cathode was characterized via cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and UV spectroscopy techniques. The assembled biofuel cell generated a maximum open circuit voltage (V oc ) of 0.485 V, short circuit current (I sc ) of 0.352 mA/cm 2 , and a maximum peak power density (P max ) of 0.032 mW/cm 2 when operating in 30 mM concentration. This system showed a stable and linear performance with a linear range of 1 mM to 30 mM glucose. The gold printed electrode process is applicable to the development of wearable and implantable abiotic biofuel cell.more » « less
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ABSTRACT Tumor heterogeneity makes cancer difficult to treat. Many small molecule cancer drugs target rapidly dividing cells on the periphery of tumors but have difficulty in penetrating deep into tumors and are ineffective at treating entire tumors. Targeting both rapidly dividing and slower growing regions of tumors is essential to effectively treat cancer. A cancer drug carrier that penetrates deep into tumors and identifies metabolically activity could supply treatment to those areas based on the local microenvironment. We hypothesized that glucose sensing bacteria could identify sugar gradients in solid tumors. To test this hypothesis, a genetic circuit was designed to trigger expression of a green fluorescent protein (GFP) reporter through the chemotaxis‐osmoporin fusion protein, Trz1, a receptor for sensing glucose and ribose sugars.
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