Here, the photoluminescent amphiphilic nanoparticles were synthesized by doping of the hydroxylated oxazolidine derivative as a highly fluorescent organic chromophore to the surface of functionalized copolymer nanoparticles containing amine groups. Prepared amphiphilic copolymer nanoparticles have variable particle sizes in the range of 58–1320 nm with various spherical morphologies depending on the concentration of 2-(dimethylamino)ethyl methacrylate (DMAEMA). Investigation of optical properties for constructed photoluminescent amphiphilic nanoparticles indicated photoinduced electron transfer (PET) phenomenon between tertiary amine groups of DMAEMA and oxazolidine molecules. The photoluminescent polymer powder samples were used for printing of encrypted information on cellulose papers by powder dusting method. Printed quick responsive (QR) codes have fluorescent emission in various colors with maximum resolution, intensity, and brightness under UV-light irradiation of 365 nm. In addition, the visualization of fingerprints by powder dusting and fluorescence imaging under UV-light irradiation (365 nm) was carried out by using photoluminescent polymer powders. The fingerprints are detectable by photoluminescent nanomaterials in a rapid and accessible manner, and all three levels of identification for fingerprint ridge patterns are achievable. Therefore, developed photoluminescent nanomaterials can offer authoritative evidence for the encryption of information, and also recognize the individual identity in a short time and with the least facilities.

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