Fabrication of an optimized fluorescer encapsulated polymer coated gelatin nanoparticle and study of its retarded release properties

In this article the preparation and characterization of a fluorescent probe, rhodamine B, encapsulated gelatin nanoparticles has been described. The retardant release properties of the same have also been studied with its probable application in drug delivery systems. To decrease the release rate of the dye, fatty acid has been polymerized on the surface of the gelatin capsules or coacervates forming protective shells. The synthesis was carried out through the coacervation method with the aim to lead to the delayed release of the fluorescer from the gelatin polysaccharide matrix. The characteristics of fatty acids loading and chain length factors affecting their release from nanocapsules were investigated. The coacervated nanoparticles had uniform spherical shape with a size distribution of 195 ± 10 nm for nanoparticles formed with myristoleic acid precursor and at 160 ± 8 nm with oleic acid precursor. Based on spectroscopic studies it was found that the loading efficiency was approximately 0.4 μg/mg of nanoparticles for poly(myristoleic acid) and 0.7 μg/mg for poly(oleic acid). A higher efficacy for poly(oleic acid) is justified due to increase in hydrophobicity with increase in polymer chain length. For the first time, to the best of my knowledge, a polymeric chain length efficacy-dependent nanoparticle has been synthesized and non-invasively characterized. The nanoparticles were found to exhibit biocompatibility and affinity for cells, as demonstrated through fluorescence microscopy. In all the cases, the results clearly demonstrate the superiority of the encapsulated nanoparticles over bare organic fluorescent dye molecules which may be applied for probe-labeling in matters of sensitive target detection. Therefore, there is enormous potential to apply these newly developed fluorescent probe encapsulated nanoparticles in various bio-detection systems.