Multimodal techniques based on synchrotron radiation X-rays for revealing interactions of metallic nanoparticles with biological matrices.

With the increasing applications of metallic nanoparticles (MNPs) in biomedicine and daily consumer products, it is crucial to explore the interactions of MNPs with biological matrices (MNPs-bio), determining the medical efficacy and biosafety. The dynamic alterations of MNPs and biological systems, as well as the complexity of the biological components, pose great challenges in clarifying the underlying details behind MNPs-bio interactions. The synchrotron radiation X-ray, as an advanced light source, has been emerging as a powerful and versatile tool to reveal the complicated MNPs-bio interaction with the advantages of label-free, in situ, strong penetration capability, quantitative analysis, high sensitivity and high resolution. It is increasingly critical to further develop multimodal techniques based on synchrotron radiation X-rays since the dynamic and complex MNPs-bio interactions generally involve alterations of composition, chemical states, structure, morphology and functions. Multimodal techniques based on synchrotron radiation X-rays have been established by integrating different synchrotron radiation X-rays techniques or combining the synchrotron radiation X-rays technique with other state-of-the-art analytical techniques, realizing a comprehensive all-aspect analysis of MNPs-bio interactions. Here, we summarize recent progress in multimodal synchrotron radiation X-ray techniques for the cross-scale analysis of MNPs-bio interactions. The perspectives on potential improvements of multimodal synchrotron radiation X-ray techniques in the future are also highlighted in the review.