Helicoidal self-ordering of cellulose microfibrils in aqueous suspension.

In many skeletal support systems of plants and animals, cellulose, chitin, and collagen occur in the form of microfibrils ordered in a chiral nematic fashion (helicoids). However, these structures remain poorly understood due to the many constituents present in biological tissues. Here we report an in vitro system that attracts by its simplicity. Only one chemical component, cellulose, is present in the form of fibrillar fragments dispersed in water. Above a critical concentration the colloidal dispersion separates spontaneously into a chiral nematic liquid crystalline phase. On drying this phase solidifies into regularly twisted fibrillar layers that mimic the structural organization of helicoids in nature.

[1]  Y Bouligand,et al.  Twisted fibrous arrangements in biological materials and cholesteric mesophases. , 1972, Tissue & cell.

[2]  F. Morehead,et al.  Some hydrodynamic properties of neutral suspensions of cellulose crystallites as related to size and shape , 1961 .

[3]  H. Hoffmann,et al.  Liquid crystalline suspensions of poly(tetrafluoroethylene) 'whiskers' , 1988, Nature.

[4]  H. J. Woods,et al.  X-ray and electron microscope studies of the degradation of cellulose by sulphuric acid. , 1953, Biochimica et biophysica acta.

[5]  M. Perutz,et al.  X-Ray and Solubility Studies of the Hæmoglobin of Sickle-Cell Anæmia Patients , 1951, Nature.

[6]  Conmar Robinson Liquid-crystalline structures in solutions of a polypeptide , 1956 .

[7]  L. Onsager THE EFFECTS OF SHAPE ON THE INTERACTION OF COLLOIDAL PARTICLES , 1949 .

[8]  D. Gray Chemical characteristics of cellulosic liquid crystals , 1985 .

[9]  D. Gray,et al.  Solid cholesteric films cast from aqueous (hydroxypropyl)cellulose , 1987 .

[10]  F. Morehead,et al.  Liquid Crystal Systems from Fibrillar Polysaccharides , 1959, Nature.

[11]  J. Willison,et al.  A liquid crystal containing cellulose in living plant tissue , 1988 .

[12]  D. Gray,et al.  Electron microscopic evidence for cholesteric structure in films of cellulose and cellulose acetate , 1988 .

[13]  J. D. Bernal,et al.  X-RAY AND CRYSTALLOGRAPHIC STUDIES OF PLANT VIRUS PREPARATIONS : I. INTRODUCTION AND PREPARATION OF SPECIMENS II. MODES OF AGGREGATION OF THE VIRUS PARTICLES. , 1941 .

[14]  M. Perutz,et al.  New X-Ray Evidence on the Configuration of Polypeptide Chains: Polypeptide Chains in Poly-γ-benzyl-L-glutamate, Keratin and Hæmoglobin , 1951, Nature.

[15]  H. Chanzy,et al.  Liquid crystal‐type assembly of native cellulose‐glucuronoxylans extracted from plant cell wall , 1991, Biology of the cell.

[16]  D. Reis,et al.  The helicoidal plant cell wall as a performing cellulose‐based composite , 1989 .

[17]  S. Caveney,et al.  SCARABAEID BEETLE EXOCUTICLE AS AN OPTICAL ANALOGUE OF CHOLESTERIC LIQUID CRYSTALS , 1969, Biological reviews of the Cambridge Philosophical Society.

[18]  D. Gray,et al.  Liquid Crystalline Structure In Aqueous Hydroxypropyl Cellulose Solutions , 1976 .