A nanoparticle composition, a device including the nanoparticle composition, and a method thereof are provided. The composition comprises nanoparticles such as Gold nanorods (NR) and electrically charged self-assembled molecular aggregates such as disodium chromoglycate (DSCG) in a common solvent such as water. The nanoparticles are assembled as, for example, side-by-side and end-to-end assemblies of nanorods, through a non-covalent interaction such as anisotropic electrostatic interaction with the electrically charged self-assembled molecular aggregates. The invention can be used in a cloaking device, a biological sensing device, a drug delivery, a meta material, a negative index material, an enhanced imaging device, and a device for solar energy conversion, and exhibits many merits such as simpler process without the need of a covalent bonding between the nanoparticles, different manners of nanoparticles assembling with same linker, higher thermal stability, cost effectiveness, and capability of gradual controlling of the degree of NR assembly, among others.