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https://www.pulsus.com/dentistry-case-report.htmlDentistry: Case Report
Euro Dentistry 2017
September 20-21, 2017
25
th
Euro Dentistry Congress
September 20-21, 2017 Dublin, Ireland
Abla Alzagameem, Dentistry: Case Report
Antioxidant and antimicrobial activity of lignin-based hydrogels for drug release applications in dental
bone regeneration
Abla Alzagameem
Brandenburg University of Technology, Germany
L
ignins are intensively studied regarding their potential as bio-based sustainable drug release material. Thus, various drugs have
been encapsulated and tested regarding their release kinetics including antimicrobial substances. Regarding their availability,
lignins are byproducts of the paper and pulping industry. They are available in huge amounts in form of so called black liquor, mainly
produced via Kraft-pulping. However, applications of technical lignins are still limited to low-quality products due to the chemical
and structural inhomogeneity. Thus, the first goal is to develop an appropriate approach for lignin extraction and purification.
The purified lignins are then studied with special focus on antioxidant and bioactivity properties depending on biomass source
and pulping process. In collaboration with the cold chain management group at the University Bonn, lignin-based polymers are
developed for biomedical applications such as drug release for dental tissue regeneration. The lignin is extracted from black liquor
via acidic precipitation, monitored by thin layer chromatography (TLC). Purification of kraft lignin was carried out by selective
extraction. Lignins are characterized by FTIR, UV-Vis, 31P NMR, SEC, XRD and microscopy (SEM). Antioxidant activity is studied
using a DPPH assay. The phenol content of lignins is determined by the Folin–Ciocalteu Micro method. The results of both methods
confirm the antioxidant ability of lignins reported in literature. In addition, it could be shown that the antioxidant activity of the
lignin fractions strongly depends on the source of the raw material (black liquor). Here, differences in biomass feedstock used for
the kraft pulping process could be the reason for this observation which still is under investigation. Bioactivity (antibacterial and
antifungal) of extracted lignins is accomplished by disk diffusion method and solution shake method. The antimicrobial activity is
tested by modifying the method ISO 22196 (2007), a quantitative method to determine the level of antimicrobial activity of polymer
surfaces. Polymer composites based on lignin and hydroxypropyl methylcellulose (HPMC) were prepared and tested regarding their
swelling behavior and mechanical stability.