In the present work, amine-functionalized nanodiamonds (NDs) have been encapsulated in liposomes and studied in order to observe the modification of their photoluminescence properties. NDs were functionalized with aromatic amines such as 1-aminopyrene and 2-aminofluorene, and the aliphatic amine 1-octadecylamine. Morphology, structural and optical properties of NDs and amine-modified NDs were analyzed by transmission electron microscopy, atomic force microscopy, scanning electron microscopy, and photoluminescence. The amine-functionalized NDs were successfully encapsulated in lecithin liposomes prepared by the green and conventional methods. The obtained results show significant changes in photoluminescent properties of functionalized NDs, and were more potentialized after liposome encapsulation. Our findings could be applied in the development of new kinds of water-dispersible fluorescent hybrids, liposome-NDs, with the capability of drug encapsulation for use in diagnostics and therapy (theragnostic liposomes). All-optical sensors with possibilities for tailoring their response for other biomedical applications can be also contemplated.

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An analysis of optical effects exhibited by blood plasma under healthy/unhealthy conditions, and of the penetrating evolution of nanovehicles conformed by nanodiamonds (NDs) encapsulating liposomes (L) within these biofluids, is presented. Optical ablation of liposome clusters was actuated and controlled by a standard two-wave mixing (λ = 532 nm, τp = 4 ns) laser light method. Radiant time exposure effects (30 min) and threshold laser energy parameters (250 mJ/cm2 numerical; 181 mJ/cm2 experimental) necessary to release NDs were identified and confirmed with similar experiments in the literature. Interactions during the sedimentation process between nanovehicles and the laser beams barrier were considered as the principal thermal damage process to achieve the release and transportation of drugs within these static fluids. The mechanical response during the release of NDs focuses on the temperature propagation, dynamic effects of nanovehicles associated with the diffusion coefficient, and some agglomeration effects. The principal findings of this research concern the threshold temperature (51.85 °C) of liposomes for the release of NDs with respect to that typically quoted in the literature (40–70 °C) for pure liposomes. The assessment of the release of NDs focuses on the numerical magnitude of Quantum Yield. Furthermore, the optical contrast enhancement was associated with NDs size agglomerations and the healthy/unhealthy conditions of fluids. This research aims to be a first proof approximation for delivery and transportation approaches to guide and interpret outcomes when combined with the vectorial nature basis of laser light and further effects once the cargo is retained in the fluids.

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