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Traditional hydrophilic wound dressings, while common, fail to effectively drain wound exudate, creating conditions favorable for bacterial growth. Similarly, newer Janus‐type dressings with hydrophobic‐hydrophilic properties also fall short, as their hydrophobic side causes excessive dryness by pulling biofluids from the wound, disrupting moisture balance. Additionally, embedding antibiotics in dressings at fixed concentrations, regardless of the infection type, reduces effectiveness and contributes to the growing problem of antibiotic resistance. In response, a single‐layered Janus paper wound dressing, designed for efficient exudate absorption and precise antibiotic delivery, is developed. The approach differs from traditional Janus‐type dressings; a hydrophilic layer is placed directly against the wound for better moisture management, while antibiotics are applied through the hydrophobic layer. To further enhance exudate management, the hydrophilic section with four extra absorbent pads is extended. The dressing's antibiotic efficacy and dosage are tailored based on antibiotic susceptibility testing, ensuring targeted treatment. The selected antibiotic is manually added but automatically delivered directly to the wound bed. The in vitro and ex vivo evaluations, using bacterial cultures on agar and porcine skin assays, respectively, confirm the dressing's superior exudate drainage and its ability to inhibit pathogen growth and reproduction, marking a significant advancement in wound care.
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Micropatternable Janus Paper as a Wearable Skin Patch for Sweat Collection and Analysis
Abstract Single‐use paper‐based wearable devices are receiving increasing attention as a novel platform for disposable, inexpensive, noninvasive, and real‐time sweat monitoring. The bidirectional liquid transport nature of paper is the most critical barrier to effectively controlling sweat samples for reliable and accurate sweat analysis. Excessive or additionally released sweat significantly interferes with analysis when mixed with old sweat. Moreover, bio‐receptors pre‐loaded in the sensing areas can backflow and move to another sensing region generating a cross‐talk issue. This work enables effective sweat sampling and delivery in paper by facilitating unidirectional sweat transport from the skin to the sensing reservoir. The design and fabrication of a single‐layered paper membrane to achieve Janus‐type properties, which only allow moisture to flow in one direction is introduced. When the hydrophobic side of the Janus paper is placed on the skin, sweat is unidirectionally self‐pumped from the hydrophobic side to the hydrophilic sensing areas, but not the reverse. The fabrication takes two steps including easy automatic and scalable printing of hydrophobic micropatterns on paper and simple heating of the printed paper for the wax penetration. Quantitative colorimetric assessment of pH, chloride, sodium, and glucose in sweat is simultaneously performed without cross‐talk between the sensing regions.
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- PAR ID:
- 10414629
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 8
- Issue:
- 17
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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