Abstract
We have demonstrated the use of conductive polylactic acid (PLA) filament for dose monitoring in a syringe-less wearable infusion pump. A channel reservoir is inlaid with conductive PLA filament. As the liquid medium is dispensed via gas pressurization by an built-in electrolysis chamber, the effective impedance of the conductive PLA filament/liquid medium column changes as well. This allows the dispensed volume to be monitored via the output voltage across a series resistor. Using 5 V sinusoidal input voltage, the output voltage decreased from ∼1.3 to ∼0.13 V as the dispensed volume of 0.1 mol/L PBS increased from 0 to 1000 μL. Similarly, the output voltage for insulin analog decreased from ∼0.64 to 0.126 V for the same volume displaced. Repeated dispensing runs with 0.1 mol/L PBS showed good consistency (standard deviation less than 10 mV). The rate of change of the output voltage with elapsed time varied accordingly for the different flow rates (0.25–1.00 mL/h or ∼4–17 μL/min). At electrolysis voltages of 1.5 and 5 V, the respective output voltage were 1.04 and 0.33 V. These corresponded to flow rates of ∼3 and 10 mL/h (∼50 and 160 μL/ min).
Original language | English |
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Pages (from-to) | 1080-1089 |
Number of pages | 10 |
Journal | Sensors and Actuators, B: Chemical |
Volume | 258 |
DOIs | |
Publication status | Published - 2018 Apr 1 |
Bibliographical note
Funding Information:This work was supported by National Research Foundation of Korea ( NRF-2015 R1D1A1A01060317 and NRF-2017 R1A2B4005133 ). The authors would like to thank Miri Park for the assistance with the SEM and Prof. Ahjeong Son at Ewha Womans University for the laboratory resources.
Publisher Copyright:
© 2017 Elsevier B.V.
Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
Keywords
- Dose monitoring
- Infusion pump
- Insulin analog
- PLA filament
- Wearable
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Instrumentation
- Condensed Matter Physics
- Surfaces, Coatings and Films
- Metals and Alloys
- Electrical and Electronic Engineering
- Materials Chemistry