Polypeptide-templated synthesis of hexagonal silica platelets.
Several studies have demonstrated the use of biomimetic approaches in the synthesis of a variety of inorganic materials. Poly-L-lysine (PLL) promotes the precipitation of silica from a silicic acid solution within minutes. The molecular weight of PLL was found to affect the morphology of the resulting silica precipitate. Larger-molecular weight PLL produced hexagonal silica platelets, whereas spherical silica particles were obtained using low-molecular weight PLL. Here we report on the polypeptide secondary-structure transition that occurs during the silicification reaction. The formation of the hexagonal silica platelets is attributed to the PLL helical chains that are formed in the presence of monosilicic acid and phosphate ions. Hexagonal PLL crystals can also serve as templates in directing the growth of the silica in a manner that generates a largely mesoporous silica phase that is oriented with respect to the protein crystal template.
Tomczak
Melanie M
MM
Materials and Manufacturing Directorate, Air Force Research Laboratory, Dayton, Ohio 45433, USA.
Glawe
Diana D
DD
Drummy
Lawrence F
LF
Lawrence
Charles G
CG
Stone
Morley O
MO
Perry
Carole C
CC
Pochan
Darrin J
DJ
Deming
Timothy J
TJ
Naik
Rajesh R
RR
D008855:Microscopy, Electron, Scanning; D008958:Models, Molecular; D010316:Particle Size; D011107:Polylysine / Q000737:chemistry*; D012824:Silicic Acid / Q000737:chemistry; D012822:Silicon Dioxide / Q000138:chemical synthesis* / Q000737:chemistry; D013499:Surface Properties
D012824:Silicic Acid; D011107:Polylysine; D012822:Silicon Dioxide