The authors acknowledge support from Flinders University and the Australian Research Council (ARC).
Rapid Fabrication of Micro- and Nanoscale Patterns by Replica Molding from Diatom Biosilica†
Article first published online: 7 AUG 2007
Copyright © 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Advanced Functional Materials
Volume 17, Issue 14, pages 2439–2446, September, 2007
How to Cite
Losic, D., Mitchell, J. G., Lal, R. and Voelcker, N. H. (2007), Rapid Fabrication of Micro- and Nanoscale Patterns by Replica Molding from Diatom Biosilica. Adv. Funct. Mater., 17: 2439–2446. doi: 10.1002/adfm.200600872
- Issue published online: 18 SEP 2007
- Article first published online: 7 AUG 2007
- Manuscript Revised: 13 DEC 2006
- Manuscript Received: 22 SEP 2006
- Flinders University
- Australian Research Council (ARC)
- Soft lithography
Diatoms are single-celled micro-algae that possess an exoskeleton (called frustule) comprised of diverse and highly ordered 3D porous silica structures and that hold considerable promise for biological or biomimetic fabrication of nanostructured materials and devices. We have used, for the first time, a soft lithographic approach of replica molding to replicate porous diatom structures into polymers. Two centric diatom species, Coscinodiscus sp., Thalassiosira eccentrica cultured in our laboratory were used as masters for replication. In the first step, replica molding onto soft and elastic polymer using poly(dimethylsiloxane) PDMS produced a negative replica of the diatom frustule. These PDMS replicas were then used as a mold to fabricate the positive polymer replicas of diatoms using a mercaptol ester type UV curable polymer (NOA 60). Fabricated polymer replicas were characterized using scanning electron microscopy (SEM) and atomic force microscopy (AFM). In all cases, diatom micro- and nanoscale porous structures were successfully transferred with high precision into polymer replicas. Such an accomplishment effectively demonstrates the potential for using diatoms as blueprints for rapid and simple fabrication of polymer nanostructures. The prepared replicas were used as diffraction gratings and as nanowells to hold polymeric nanoparticles effectively demonstrating the functional properties of these biomimetic structures.