Microalgae-Mediated Biological Synthesis of Silver Nanoparticles: Optimization and Morphological Characterization
Hui Ying THE, Man Kee LAM, Voon-Loong WONG, Wai Hong LEONG, Inn Shi TAN, Henry Chee Yew FOO
Abstract. Silver nanoparticles (AgNPs) are essential in biomedical and water treatment applications due to their superior localized surface plasmon resonance (LSPR) property. This study adopted C. vulgaris as a bio-reducing agent for eco-friendly AgNP synthesis from silver nitrate (AgNO₃) via photo-induced reduction. The reaction rate was found to be highly dependent on the illumination source. To optimize the process, the volumetric ratio of C. vulgaris-to-precursor solution was varied alongside the illumination wavelengths from different LED colors (white, blue, red, and green). The optimal C. vulgaris-to-precursor ratio was 1:5, achieving a LSPR increment of 0.407 a.u. within 35 min. Blue light accelerated the reaction, reducing the time to 30 min and yielding a higher LSPR increment of 0.445 a.u.. Particle size analysis further confirmed the enhanced synthesis under blue light, with a narrower particle size distribution peak in the 39 – 47 nm range. FESEM revealed larger particle sizes due to aggregation in drying. However, upon re-suspension of the dried AgNPs, smaller particles were recovered with HRTEM showing individual AgNPs as small as ~16 nm. The results highlight the positive role of C. vulgaris in mediating competitive nanosized silver production through a greener, more sustainable approach.
Keywords
Microalgae, Silver Nanoparticles, Green Synthesis, Plasmon Resonance, Photoinduction
Published online 1/15/2026, 8 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Hui Ying THE, Man Kee LAM, Voon-Loong WONG, Wai Hong LEONG, Inn Shi TAN, Henry Chee Yew FOO, Microalgae-Mediated Biological Synthesis of Silver Nanoparticles: Optimization and Morphological Characterization, Materials Research Proceedings, Vol. 59, pp 185-192, 2026
DOI: https://doi.org/10.21741/9781644903957-24
The article was published as article 24 of the book Separation Technology
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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