Nanofabrication of Ordered Multilayers by Alternate Adsorption of Polyions, Proteins and Nanoparticles:  From Planar Films to Microtemplates.


Yuri M. LVOV

Institute for Micromanufacturing, Louisiana Tech University, Ruston, LA, 71272


1.       General idea of the layer-by-layer assembly, polyanion / polycation films.

2.       Protein / polyion multilayers, sequential reactions in multiprotein films.

3.       Ordered nanoparticle / polyion films; conception of  "polyion electrostatic glue."

4.        Shell assembly onto nanospheres and nanotubules.  Empty polyion capsules.

Layer-by-layer self-assembly of molecularly organized films was generalized for use with linear polyions, nanoparticles, dye and proteins. The formation of alternate outermost layers of the opposite charge at every adsorption cycle is the key point of the procedure. An alternate assembly of linear polyanions and polycations typically provides 1-2 nm growth step for a bilayer, and a number of bilayers, which can be built up, are two-three hundreds.

Protein architecture: Multilayer buildup by alternation of linear polyions and 20 different proteins was elaborated. Enzymes in films preserved bioactivity. Film-superlattices containing ordered layers of more than one protein species were constructed. Multi-enzymatic sequential reactions with directed transfer of products were realized.

We designed ordered molecular films containing from 1 up to 50 monolayers of 10, 45 and 75 nm diameter nanoparticles connected by polycation interlayers. The conception of "polyion glue" for nanoparticle multilayer architecture permitted to assemble films with planned ordering of silica, TiO2, CeO2, Al2O3, MnO2.

An assembly of organized nanoparticle shells onto microspheres was performed: firstly, by adsorption of polycation polyethyleneimine we converted surface charge of negative 300-nm diameter latex to the positive one, and at the second step we adsorbed an ordered shells of 75-nm or 45-nm silica, and gold. Hollow shells from polyion formed on soluble latex precursors were loaded with enzymes and drugs for a controllable release. In the second approach a sequential treatment of 500-nm diameter lipid tubules with polyions and negatively charged nanoparticles (silica, gold) resulted in formation of nanoparticle “caps” which sealed the end of the tubules. Addition of 1 % of charged lipids during the tubule formation and application of the described above procedure gave nanoparticle helixes inside the tubules.


1.       Book: “Protein Architecture: Interfacing molecular assembly and immobilization biotechnology.” Editors: Y.Lvov and H.Mohwald, M. Dekker Publ, NY, 2000, p.1-396

2.       Y. Lvov, R. Price, B. Gaber, J. Schnur, Langmuir, 2000, v.26, 5932-5936 “Nanopatterning on biologically derived microstructures”

3.       Y. Lvov, J. Rusling, D. Thomsen, T. Kunitake, J. Chem. Soc., Chem. Commun., 1998, 1229-1230 “High-speed multilayer assembly by alternate adsorption of nanoparticles and linear polycation”.

4.       Y. Lvov,  Z. Lu, J. Rusling, J. Am. Chem. Soc., 1998, v.120, 4073-4080 “Direct electrochemistry of myoglobin and cytochrome P450 in alternate layer-by-layer films with DNA and other polyions”

PATENT:   M. Onda, Y. Lvov, T. Kunitake,  “Multiple Layered Functional Thin Films” February 21, 2000, US patent 6020175.