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Publication Date

Summer 2010

Degree Type

Thesis - Campus Access Only

Degree Name

Master of Science (MS)




Daryl K. Eggers


Biosilica, silaffins

Subject Areas

Chemistry, Biochemistry; Engineering, Materials Science


Synthesis of intricate amorphous silica structures at ambient conditions has been mastered in nature by diatoms. Better understanding of the mechanism of silica formation in diatoms could lead to a greater control over the industrial silica fabrication process and the morphology of the silica produced.

Long-chain polyamines and silaffin peptides extracted from the glass walls of diatoms have been shown to precipitate silica at ambient conditions in vitro. In this qualitative research, bio-inspired amino-based compounds were tested for their silica-precipitating ability in various buffered solutions and with different silica precursors. The study aimed to produce novel silica structures. The morphology of the synthesized silica precipitates was studied using scanning electron microscopy. The experimental results indicated that the reaction media, the nature of the amino-based additive, and the nature of silica precursor all have an effect on silica production and on the morphology of the silica produced. Spermine and spermidine exhibited the strongest ability to induce silica precipitation. Experiments with L-lysine and spermine produced the most morphologically distinct silica structures.