Laser-processed parchment paper for fabrication of chronic wound dressings with selective oxygenation

Manuel Ochoa, Purdue University


Chronic non-healing wounds (e.g., diabetic foot ulcers and bed sores) impact over 6.5 million Americans per year, costs in excess of $25 billion to treat on an annual basis, and are on the rise due to increasing levels of obesity and diabetes compounded by an aging population. A major inhibitor of healing is suboptimal oxygenation of the wound bed. Unlike acute injuries that receive sufficient oxygen via a functional blood vessel network, chronic wounds often suffer from the lack of a proper vascular network; thus being incapable of providing sufficient oxygen for tissue growth. Typical medical treatment of hypoxic chronic wounds typically employs hyperbaric oxygen therapy, which requires bulky equipment and often exposes large areas of the body to unnecessarily elevated oxygen concentrations that can damage healthy tissue. A more recent and convenient approach is topical oxygen therapy (TOT), in which the dressing itself can generate and deliver the required oxygen; various such systems exist commercially, but they are not economical, they do not provide selective delivery to only hypoxic regions, and their design does not permit further expansion for other wound-healing therapies on the same platform. A more practical implementation of such dressings would comprise an inexpensive dressing platform for adaptive oxygen therapy which is capable of delivering appropriate oxygen gas where and when it is needed. This work presents a low-cost alternative for continuous oxygen delivery comprising of an inexpensive, paper-based, biocompatible, flexible platform for locally generating and delivering oxygen to selected hypoxic regions. The platform takes advantage of recent developments in the fabrication of flexible microsystems including the incorporation of paper as a substrate and the use of inexpensive laser machining. The use of paper simultaneously provides structural strength, flexibility, mammalian cell biocompatibility, as well as selective filtering functionality, i.e., it allows for oxygen to pass through while preventing aqueous solutions to reach the tissue. The laser machining enables the precise definition of oxygen generating regions that match the hypoxic wound profile. Together these two technologies enable the development of a low-cost patch/wound-dressing with customized, wound-specific oxygen generating regions.




Ziaie, Purdue University.

Subject Area

Engineering|Biomedical engineering

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