title: Fabrication and characterization of a nitric oxide-releasing nanofibrous gelatin matrix.
abstract: Nitric oxide (NO) plays an important role in cardiovascular homeostasis, immune responses, and wound repair. The pro-angiogenic and antimicrobial properties of NO has stimulated the development of NO-releasing materials for wound dressings. Gelatin, an abundant natural biodegradable polymer derived from collagen, is able to promote wound repair. S-Nitroso-N-acetylpenicillamine (SNAP) can release NO under physiological conditions and when exposed to light. The objective of this project was to fabricate a NO-releasing gelatin-based nanofibrous matrix with precise light-controllable ability. Results showed that under controlled phase separation fabrication conditions, the gelatin formed a highly porous matrix with the nanofiber diameter ranging from 50 to 500 nm. Importantly, the removal of the trace amount of divalent metal ions within gelatin generated a more stable nanofibrous structure. N-acetyl-D-penicillamine (NAP) was functionalized onto the matrix and nitrosated with t-butyl nitrite, yielding a SNAP-gelatin matrix. Analysis of the photoinitiated NO-release showed that the SNAP-gelatin matrices released NO in a highly controllable manner. Application of increasing light intensities yielded increased NO flux from the matrices. In addition, the dried matrices stored in dark at 4 °C maintained stable NO storage capacity, and the purified (ion-removed) gelatin preserved higher NO-releasing capacity than nonpurified gelatin. The antibacterial effect from the SNAP-gelatin matrices was demonstrated by exposing Staphylococcus aureus ( S. aureus ) to a light-triggered NO flux. This controllable NO-releasing scaffold provides a potential antibacterial therapeutic approach to combat drug resistant bacteria.
authors.affiliation: Stem Cell and Tissue Engineering Lab, Department of Biomedical Engineering, Michigan Technological University, Houghton, 49931, United States.
authors.forename: Caleb
authors.initials: C
authors.lastname: Vogt
authors.forename: Qi
authors.initials: Q
authors.lastname: Xing
authors.forename: Weilue
authors.initials: W
authors.lastname: He
authors.forename: Bowen
authors.initials: B
authors.lastname: Li
authors.forename: Megan C
authors.initials: MC
authors.lastname: Frost
authors.forename: Feng
authors.initials: F
authors.lastname: Zhao
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology* / Q000528:radiation effects; D001458:Bandages; D002118:Calcium / Q000737:chemistry; D003300:Copper / Q000737:chemistry; D004355:Drug Stability; D005780:Gelatin / Q000737:chemistry*; D007501:Iron / Q000737:chemistry; D008027:Light; D008826:Microbial Sensitivity Tests; D057139:Nanofibers / Q000737:chemistry* / Q000648:ultrastructure; D020030:Nitric Oxide Donors / Q000737:chemistry / Q000494:pharmacology* / Q000528:radiation effects; D055668:Photochemical Processes; D016062:Porosity; D026423:S-Nitroso-N-Acetylpenicillamine / Q000737:chemistry / Q000494:pharmacology* / Q000528:radiation effects; D017550:Spectroscopy, Fourier Transform Infrared; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D020030:Nitric Oxide Donors; D003300:Copper; D026423:S-Nitroso-N-Acetylpenicillamine; D005780:Gelatin; D007501:Iron; D002118:Calcium