Synthesis of Ordered Biosilica Materials  

作　　者：王荔军 王运华 李敏 范明生 张福锁 吴学民 杨文胜 李铁津 

出　　处：《Chinese Journal of Chemistry》2002年第1期107-110,共4页中国化学（英文版）

基　　金：theNationalNaturalScienceFoundationofChina (No 39870 480 )andNationalKeyBasicResearchFoundation(No.G19990 1170 0 )

摘　　要：Biogenic silica with amazing diversity of nanostructure shells, fibers andgranules in diatoms and sponges is mediated by proteins and polysaccharides and forms at ambientpressure and temperatures. Chemical synthetic methods, in contrast, have to rely on extreme pHand/or surfactants to induce the condensation of silica precursors into specific patterns. One kindof benign synthesis method through plant cell wall template-directed ordered biosilica materialsunder ambient conditions is intriguing in this context. Organized silica materials in intercellularspaces of epidermal cells of tall fescue leaves were synthesized through molecular recognitionbetween Si-OH and polysaccharide-OH or glycoprotein-OH of main components of plant cell walls andcellular processing as well when Si(OEt)_4 was supplied rather than monosilicic acid. Thebiosynthesis of structural silica in tall fescue plant was correlated with the Si species applied,reflecting the slower condensation from tetraethoxysilane (TEOS) and thus providing greateropportunities for structural control by the underlying matrix of cell walls. The composition wasestimated by energy dispersive X-ray (EDX) spectra on a scanning electron microscope. All organizedstructures showed carbon, oxygen and silicon peaks, indicating that their formations differ fromnatural siliceous process.Biogenic silica with amazing diversity of nanostructure shells, fibers andgranules in diatoms and sponges is mediated by proteins and polysaccharides and forms at ambientpressure and temperatures. Chemical synthetic methods, in contrast, have to rely on extreme pHand/or surfactants to induce the condensation of silica precursors into specific patterns. One kindof benign synthesis method through plant cell wall template-directed ordered biosilica materialsunder ambient conditions is intriguing in this context. Organized silica materials in intercellularspaces of epidermal cells of tall fescue leaves were synthesized through molecular recognitionbetween Si-OH and polysaccharide-OH or glycoprotein-OH of main components of plant cell walls andcellular processing as well when Si(OEt)_4 was supplied rather than monosilicic acid. Thebiosynthesis of structural silica in tall fescue plant was correlated with the Si species applied,reflecting the slower condensation from tetraethoxysilane (TEOS) and thus providing greateropportunities for structural control by the underlying matrix of cell walls. The composition wasestimated by energy dispersive X-ray (EDX) spectra on a scanning electron microscope. All organizedstructures showed carbon, oxygen and silicon peaks, indicating that their formations differ fromnatural siliceous process.

关 键 词：ordered biosilica material template synthesis BIOMINERALIZATION cellwall tall fescue plant 

分 类 号：TQ424[化学工程]