Free-Electron-Laser Coherent Diffraction Images Individual Drug-Carrying Liposome Particles in Solution
Using the excellent performances of the SACLA (RIKEN/HARIMA, Japan) X-ray free electron laser (X-FEL), coherent diffraction imaging (CDI) was used to detect individual liposome particles in water, with or without inserted doxorubicin nanorods. This was possible because of the electron density differences between the carrier, the liposome, and the drug. The result is important since liposome nanocarriers dominate at present the drug delivery systems. In spite of the low cross section of the original ingredients, the diffracted intensity of drug-free liposomes was sufficient for spatial reconstruction yielding quantitative structural information. For particles containing doxorubicin, the structural parameters of the nanorods could be extracted from CDI. Furthermore, the measurement of the electron density of the solution enclosed in each liposome provides direct evidence of the incorporation of ammonium sulphate into the nanorods. Overall, ours is an important test for extending the X-FEL analysis of individual nanoparticles to low cross-section-systems in solution, and also for its potential use to optimize the manufacturing of drug nanocarriers. The complete results have been published in the Nanoscale.
http://pubs.rsc.org/en/content/articlelanding/2018/nr/c7nr09395k#!divAbstract
Fig. 1 Cryo-electron microscopy images of liposome particles. (a) blank and (b) doxorubicin-containing liposomes (the black dots in (a) are Au nanoparticles decorating one of the liposomes). (c) Processed doxorubicin-containing liposome compliant with the human therapy requirements, with more uniform size and shape. Scale bars = 200 nm.
Fig. 2 CDI patterns of four individual doxorubicin-containing liposomes. (a)-(d), diffraction patterns; (e)-(h), their corresponding reconstructed images. Bars = 200 nm.
Journal Links: http://pubs.rsc.org/en/content/articlelanding/2018/nr/c7nr09395k#!divAbstract