Fabrications of bifunctional janus and triblock saturn colloids

A synthetic approach for the fabrications of Janus and Saturn colloids was demonstrated by the sequential embedment and surface modification of silica colloids. Electrospinning of poly(methyl methacrylate) (PMMA) and poly(4-vinyl pyridine) (P4VP) blends produced polymer fibers with high specific surfaces for the colloid adsorption and embedment. Colloid adsorption on fiber surfaces was established by the interaction between silanol and pyridine groups located on silica and P4VP, respectively. The thermally-induced colloid embedding was precisely manipulated by the heat treatment, which allowed the uniform and controllable colloid embedding. The exposed colloid surfaces were selectively modified by the chemical vapor deposition of silancs with desired functional groups, followed by labeling with magnetite or gold nanoparticles. Synthesis of bifunctional Janus and triblock Saturn colloids were demonstrated and discussed.