Size-dependent penetration depth of colloidal nanoparticles into cell spheroids
Dingcheng Zhu, Dennis Brückner, Martin Sosniok, Marvin Skiba, Neus Feliu, Marta Gallego, Yang Liu, Florian Schulz, Gerald Falkenberg, Wolfgang J. Parak, Carlos Sánchez-Cano
Abstract
The penetration of nanoparticle (NP)-based drugs into tissue is essential for their use as nanomedicines. Systematic studies about how different NP properties, such as size, influence NP penetration are helpful for the development of NP-based drugs. An overview of how NPs of different sizes may penetrate three-dimensional cell spheroids is given. In particular different techniques for experimental analysis are compared, including mass spectrometry, flow cytometry, optical fluorescence microscopy, X-ray fluorescence microscopy, and transmission electron microscopy. An experimental data set is supplemented exclusively made for this review, in which the results of different techniques are visualized. Limitations of the analysis techniques for different types of NPs, including carbon-based materials, are discussed.