Alginate aerogels carrying calcium, zinc and silver cations for wound care: Fabrication and metal detection

• Published in: The Journal of supercritical fluids 2019-11, Vol.153, p.104545, Article 104545
• Main Authors: Raman, S.P., Keil, Claudia, Dieringer, Paul, Hübner, Christopher, Bueno, Alberto, Gurikov, Pavel, Nissen, Jörg, Holtkamp, Michael, Karst, Uwe, Haase, Hajo, Smirnova, Irina
• Format: Article
• Language: English
• Subjects: Anti-Inflammatory; Atomic absorption spectrometry; Silver alginate aerogel; Wound dressing application; Zinc alginate aerogel
• ISSN: 0896-8446; 1872-8162
• DOI: 10.1016/j.supflu.2019.104545

[Display omitted] •Strong leaching of Zn cations is observed in solvent exchange step.•Alginate aerogel contains 6–7 times more Ca compared to Zn.•Ag presence leads to higher Zn levels in the aerogels.•Higher Zn release in HEPES buffer in the presence of Ca.•Zn-enriched supernatants suppress NO production in stimulated RAW 264.7 macrophages. Calcium-alginate aerogels augmented with zinc and silver can provide the next generation superabsorbent medical devices for advanced wound care with high cell and tissue tolerability and controlled compound release rates during wound healing. In this study, we addressed the fabrication and metal detection of alginate-based aerogels with these immunoactive cations. All three cations were incorporated into the alginate aerogel, albeit in different quantities, due to different magnitudes of leaching during solvent exchange step; an effect not reported previously. Silver addition led to an increase in aerogel zinc content without influencing calcium incorporation. All three metal ions were released into supernatants upon swelling aerogels in aqueous solutions, comparable to those measured for common wound dressings in human and animal injury models. The in vitro bioactivity studies showed that Zn-enriched swelling supernatants were able to suppress NO production in stimulated RAW 264.7 macrophages, indicating an effective anti-inflammatory activity.