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Abstract Chronic wounds present significant therapeutic challenges due to prolonged inflammation and bacterial infections, impeding healing. Conventional medicinal dressings typically deliver a single drug with a fixed release profile and lack responsiveness to variations in wound size, nature, or severity. This study introduces an innovative microneedle (MN) patch designed with different microneedle geometries and capable of dual‐drug delivery to address irregular wounds and complex therapeutic requirements. Utilizing CO₂ laser lithography, microneedle molds are fabricated with diverse geometries by precisely controlling laser parameters such as speed, power, and focus, achieving needle heights ranging from 162 ± 30 µm to 1570 ± 40 µm. The patch facilitates simultaneous delivery of simvastatin (SIM) for anti‐inflammatory and tetracycline hydrochloride (TH) for antibacterial properties, targeting different skin depths. In vitro diffusion studies confirm geometry‐dependent drug release profiles, with SIM achieving controlled release over three days and TH exhibiting sustained release over four days. Biocompatibility assays confirmed safety and enhanced fibroblast migration is noted in wound‐healing studies. Antimicrobial testing reveals a 99.9% reduction in bacterial viability. This cost‐effective and scalable approach enables precise, localized delivery and customization of MN arrays to match various wound geometries, offering a versatile platform for personalized medicine and improved chronic wound management.
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Impact of Carbon Source on Bacterial Cellulose Network Architecture and Prolonged Lidocaine Release
The biosynthesis of bacterial cellulose (BC) is significantly influenced by the type of carbon source available in the growth medium, which in turn dictates the material’s final properties. This study systematically investigates the effects of five carbon sources—raffinose (C18H32O16), sucrose (C12H22O11), glucose (C6H12O6), arabinose (C5H10O5), and glycerol (C3H8O3)—on BC production by Komagataeibacter hansenii. The varying molecular weights and structural characteristics of these carbon sources provide a framework for examining their influence on BC yield, fiber morphology, and network properties. BC production was monitored through daily measurements of optical density and pH levels in the fermentation media from day 1 to day 14, providing valuable insights into bacterial growth kinetics and cellulose synthesis rates. Scanning electron microscopy (SEM) was used to elucidate fibril diameter and pore size distribution. Wide-angle X-ray scattering (WAXS) provided a detailed assessment of crystallinity. Selected BC pellicles were further processed via freeze-drying to produce a foam-like material that maximally preserves the natural three-dimensional structure of BC, facilitating the incorporation and release of lidocaine hydrochloride (5%), a widely used local anesthetic. The lidocaine-loaded BC foams exhibited a sustained and controlled release profile over 14 days in simulated body fluid, highlighting the importance of the role of carbon source selection in shaping the BC network architecture and its impact on drug release profile. These results highlight the versatility and sustainability of BC as a platform for wound healing and drug delivery applications. The tunable properties of BC networks provide opportunities for optimizing therapeutic delivery and improving wound care outcomes, positioning BC as an effective material for enhanced wound management strategies.
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- Award ID(s):
- 2332640
- PAR ID:
- 10629804
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Polymers
- Volume:
- 16
- Issue:
- 21
- ISSN:
- 2073-4360
- Page Range / eLocation ID:
- 3021
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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