1. Microfluidic Bandage for Localized Oxygen-Enhanced Wound Healing
Zameer H. Merchant, Joe F. Lo, David T. Eddington
Biological Microsystems Lab, Department of Bioengineering,
University of Illinois at Chicago

2. Importance of Oxygen in Wound Healing
Oxygen – hyperoxic conditions1,2
02 is converted to Reactive Oxygen Species (ROS)
Required for bactericidal activity
Key step in wound healing pathway in low concentrations
Topical oxygen accelerates angiogenesis by inducing production of Vascular Endothelial Growth Factor (VEGF)
Induces collagen deposition and the tensile strength of skin
May trigger the differentiation of fibroblasts to myofibroblasts, cells responsible for wound contraction.
Franz Michael G, "Chapter 6. Wound Healing" (Chapter). Doherty GM: CURRENT Diagnosis & Treatment: Surgery, 13e:
Gordillo, G., & Sen, C. (2003). Revisiting the essential role of oxygen in wound healing. The American Journal of Surgery , 186,

3. Oxygen-Enhanced Wound Healing Techniques
Current
Future1
Portable device: available bedside and at home
Localized to wound site
Rapid diffusion of oxygen
Inexpensive
Can deliver oxygen directly to superficial wounded tissue severed from circulation
No risk of multi-organ oxygen toxicity
Hyperbaric Oxygen Therapy (HBO)
Topical Oxygen Therapy
Gordillo, G., & Sen, C. (2003). Revisiting the essential role of oxygen in wound healing. The American Journal of Surgery , 186,

4. Microfluidic Bandage

5. Device Fabrication
Photolithography

6. Device Fabrication

7. Measuring Oxygen Diffusion
Calculation of [O2] after diffusion through PDMS membrane
FOXY slide (ruthenium-coated oxygen-sensing chip)
O2 quenches ruthenium fluorescence intensity
Calibration curve established by exposing FOXY slide to known oxygen concentrations
Data empirically fit to a Stern-Volmer model
Oxygen-sensing chip

8. Characterization: Oxygen Modulation

9. Characterization: Oxygen Penetration
Determine the “effective” range of oxygen penetration into tissue directly beneath the PDMS membrane
Extent of oxygen penetration measured using phantom tissue (3% agarose)
Depth of phantom tissue varied between 0.2 and 1.0mm
Diffused oxygen concentration measured 5 minutes after device was connected to 100% O2 gas line
Measured diffused oxygen concentration here

10. Characterization: Oxygen Penetration

11. Non-Conformal Bandage
Characterization: Localization of O2 Delivery in Conformal and Non-conformal Devices
Conformal Bandage
Non-Conformal Bandage
Chamber
PDMS Obstacle
PDMS Membrane

12. Characterization: Localization of O2 Delivery in Conformal and Non-conformal Devices

13. SKH1 Mice Wound Healing Day 3 Day 7 Day 10 Day 14 0 Day after wounding
Device Placebo
Control

14. SKH1 Mice Wound Healing

15. Conclusions Can consistently deliver 0.02 ±0.73 to 99.5± 4.40% O2
Can maintain localized oxygen delivery to a specified area even with a non-planar irregularity
Can deliver ~80% O2 through 0.8 mm of agar tissue phantom within 5 minutes
Device is compatible with normal wound healing
Can be used to provide oxygen-enhanced wound treatment

16. Acknowledgments
Financial support from the National Science Foundation and Department of Defense, EEC-NSF Grant #
Professor David T. Eddington – Biological Microsystems Lab, UIC
Dr. Joe F. Lo
Dr. DiPietro – Center for Wound Healing, UIC
Dr. Christos Takoudis and Dr. Greg Jursich