Silver and gold nanoparticles stabilized with plant extracts as a basis for the production of topical hydrogels

[M. S. Tasić]

[14] listova, 268 str.

Bibliografija: str. 212-256

Materials and chemical technologies

Silver and gold nanoparticles have found significant applications in medicine and pharmacy due to their unique properties, such as small size, high surface-to-volume ratio, pronounced biological activity, and good biocompatibility. The subject of this thesis was the green synthesis of silver and gold nanoparticles using biomolecules from aqueous plant extracts, and the investigation of their potential application in cosmetic formulations. The research was focused on the development of green synthesis and stabilization procedures for silver and gold nanoparticles using aqueous leaf extracts of cultivated strawberry (Fragaria × ananassa Duch.), wild raspberry (Rubus idaeus L.), and blackberry (Rubus spp.), obtained by extraction at room and boiling temperature. The leaves of these plants, belonging to the Rosaceae family, are rich in biomolecules acting as reducing and stabilizing agents. The chemical composition of the extracts includes aromatic hydrocarbons, alcohols, ketones, aldehydes, monoterpenes, C13-norisoprenoids, and phenolic compounds, and was analyzed using UHPLC-MS and ICP-OES techniques. The synthesized nanoparticles were characterized using various analytical techniques, including UV-Vis and FTIR spectrophotometry, XRD, SEM, EDX, and DLS analysis. Their stability and biological activity, including antioxidant, antimicrobial, and cytotoxic properties, were evaluated. The characterized nanoparticles were subsequently incorporated into hydrogels intended for potential topical application. The physicochemical properties of the obtained hydrogels (pH value, electrical conductivity, and viscosity), their stability, and biological activity (antioxidant and anti-inflammatory) were monitored over defined time intervals. The photoprotective potential of the formulations was assessed by determining the sun protection factor, critical wavelength, UVA star rating, safety index, and UVA/UVB ratio. The obtained results indicate that the developed hydrogels are stable systems during one year of storage in the dark at T=4°C and T=22°C, with preserved structural and chemical integrity. The tested formulations exhibited satisfactory stability, promising photoprotective and biological activity, indicating their significant potential for further application in cosmetic and medical products.

zelena sinteza; nanočestice srebra; nanočestice zlata; biljni ekstrakti; hidrogelovi; biološka aktivnost; fotoprotektivna aktivnost

green synthesis; silver nanoparticles; gold nanoparticles; plant extracts; hydrogels; biological activity; photoprotection

546.57+546.59:615.322:554.733.432(043.3)

Т 350 Chemical technology and engineering

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