Objective To develop a method for the efficient assembly of viral or multimeric proteins into virus-like particles (VLP) or other macro structures. Results Protein monomers were assembled by eliminating calcium ions through precipitation. The model protein, rotavirus VP6, assembled into stable, long nanotubes with better quality than the assemblies obtained directly from cell culture. Nanotube length was directly proportional to the initial concentration of VP6 monomers, in accordance with the classic nucleation theory of capsid assembly. The quality of the obtained assemblies was confirmed when the nanotubes were functionalized with metals, yielding unique nanobiomaterials. Assembly efficiency was improved in comparison with other previously proposed methods. Conclusions The novel method presented here is simpler and faster than other reported methods for the assembly and disassembly of viral proteins, a step needed for most applications.