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Updated: Oct 17, 2025
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High-throughput Identification of Bacteria Repellent Polymers for Medical Devices
Published on: November 5, 2016
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Properties of Mosquito Repellent-Plasticized Poly(lactic acid) Strands.
António B Mapossa1,2, Jorge López-Beceiro3, Ana María Díaz-Díaz3
1Institute of Applied Materials, Department of Chemical Engineering, University of Pretoria, Lynnwood Road, Private Bag X20, Hatfield, Pretoria 0028, South Africa.
Molecules (Basel, Switzerland)
|October 13, 2021
Summary
This study explores using biodegradable poly(lactic acid) (PLA) to create wearable mosquito repellent devices. The research demonstrates that DEET and IR3535 act as effective plasticizers, enhancing PLA
Area of Science:
- Polymer Science
- Materials Science
- Entomology
Background:
- Poly(lactic acid) (PLA) is a biodegradable polymer with potential to replace petrochemicals.
- Developing sustainable materials for wearable devices is crucial for environmental and consumer applications.
- Mosquito repellents are essential for public health, necessitating innovative delivery systems.
Purpose of the Study:
- To investigate the potential of PLA as a sustainable material for wearable mosquito repellent devices.
- To evaluate DEET and IR3535 as plasticizers for PLA in repellent formulations.
- To characterize the physical and release properties of PLA-based repellent devices.
Main Methods:
- Twin screw extrusion compounding to prepare PLA strands with DEET and IR3535.
- Differential Scanning Calorimetry (DSC) to study thermal properties and plasticizing effects.
- Rheological studies to analyze melt behavior of PLA/repellent blends.
- Raman spectroscopy to investigate DEET concentration gradients.
- Desorption studies at 50 °C to analyze release kinetics, fitted to a modified Peppas-Sahlin model.
Main Results:
- DEET and IR3535 effectively plasticized PLA, reducing its glass transition temperature.
- PLA/repellent blends exhibited shear-thinning pseudoplastic behavior.
- Non-Fickian Type II transport governed DEET desorption from the PLA matrix.
- Release data showed an initial rapid release followed by a sustained, near-constant rate.
Conclusions:
- PLA is a viable, sustainable material for developing effective wearable mosquito repellent devices.
- DEET and IR3535 serve dual roles as active ingredients and plasticizers in PLA formulations.
- The controlled release profile suggests potential for long-lasting efficacy in PLA-based repellents.
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