Layer-by-layer nanoshell assembly on colloids through simplified washless process.

A none-washing technique for layer-by-layer deposition of polyelectrolyte on colloids based on careful monitoring of colloid recharging is elaborated. It allows applying the technique for colloid systems in larger scale than laboratory, and avoiding the expensive washing procedure with centrifugation or filtration. The colloidal aggregation process depends on the cycle of sequential polycation/polyanion deposition and molecular weight of the polyelectrolytes used. The aggregation can be reversed by the addition of the next polyelectrolyte layer.