Nanorods of Well-Defined Length and Monodisperse Cross-Section Obtained   from Electrostatic Complexation of Nanoparticles with a Semiflexible   Biopolymer
  We show by combining small-angle X-ray scattering (SAXS) and cryo-transmission electron microscopy (cryo-TEM) that anionic silica nanoparticles (SiNPs) assemble into well-defined 1D cluster when mixed with a dilute solution of semiflexible chitosan polycation. The nanorods are stable in excess of SiNPs and composed of 10 SiNPs well-ordered into straight single strands with length Lrod \approx 184.0 nm and radius Rrod = 9.2 nm = RSiNPs. We point out that the ratio between the chitosan persistence length and the SiNP radius, which is here equal to 1, can be the determining condition to obtain such original objects. 
Li Shi (LLB, MSC), Florent Carn (MSC), Fran\c{c}ois Bou\'e (LLB),   Gervaise Mosser (LCMCP - site Paris VI), Eric Buhler (MSC)
cond-mat.soft