Nanosystems with various compositions and biological properties are being extensively investigated for drug and gene delivery applications.

Here we illustrate the synthesis of, 2-dimyristoyl-sn-glycero-3phosphocholine (DMPC) liposome based poly (dimethyldiallylammonium chloride) (PDDA) nanocapsule where PDDA and silica nanoparticles are coated on the surface of curcumin embedded liposomes. The prepared nanocapsule was analyzed using UV-vis spectroscopy, fluorescence spectroscopy, Dynamic Light Scattering technique, Scanning Electron Microscopy, Zeta-potential, Thermogravimetric analysis and Xray diffraction method. The fluorescence intensity of DMPC nanocapsules was found to be exceedingly, 60-fold, higher than free curcumin, thus, it boosts potential of such nanocapsules for various applications. The detection of Adinosine Triphosphate (ATP) was carried out by monitoring the change in the fluorescence emission of this DMPC nanocapsules while increasing the concentration of ATP molecule in the tested sample. Interestingly, fluorescence of free curcumin did not respond to ATP, whereas the fluorescence intensity of nanocapsules increased by the increase of ATP concentration, which establishes that materials prepared using nanotechnological modification of probe molecule can selectively target a particular analytical species. The nanocapsules based probe gave a linear correlation between the fluorescence intensity of DMPC nanocapsules in the concentration range 1 μM À 100 μM with the limit of detection equals to 0.5 μM. The described method is not interfered by uracil triphosphate, guanine triphosphate, cytosine triphosphate and thymine triphosphate molecules and showed good stability.