Correlative Fluorescent Scanning Probe Nanotomography Used to Study the Intracellular Distribution of Doxorubicin in MCF-7 Human Breast Adenocarcinoma Cells.

Developing technologies for efficient targeted drug delivery for oncotherapy requires new methods to analyze the features of micro- and nanoscale distributions of antitumor drugs in cells and tissues. A new approach to three-dimensional analysis of the intracellular distribution of cytostatics was developed using fluorescence scanning optical-probe nanotomography. A correlative analysis of the nanostructure and distribution of injected doxorubicin in MCF-7 human breast adenocarcinoma cells revealed the features of drug penetration and accumulation in the cell. The technology is based on the principles of scanning optical probe nanotomography and is applicable to studying the distribution patterns of various fluorescent or fluorescence-labelled substances in cells and tissues.

Identification of Ultrastructural Details of the Astrocyte Process System in Nervous Tissue of the Brain Using Correlative Scanning Probe and Transmission Electron Microscopy.

Nanoscale morphological features of branched processes of glial cells may be of decisive importance for neuron-astrocyte interactions in health and disease. The paper presents the results of a correlation analysis of images of thin processes of astrocytes in nervous tissue of the mouse brain, which were obtained by scanning probe microscopy (SPM) and transmission electron microscopy (TEM) with high spatial resolution. Samples were prepared and imaged using a unique hardware combination of ultramicrotomy and SPM. Astrocyte details with a thickness of several tens of nanometers were identifiable in the images, making it possible to reconstruct the three-dimensional structure of astrocytic processes by integrating a series of sequential images of ultrathin sections of nervous tissue in the future.

Investigation of the Distribution of Magnetic Nanoparticles in Tumor Tissues by the Method of Scanning Magnetic Force Nanotomography.

The development of effective biomedical technologies using magnetic nanoparticles (MNPs) for the tasks of oncotherapy and nanodiagnostics requires the development and implementation of new methods for the analysis of micro- and nanoscale distributions of MNPs in the volume of cells and tissues. The paper presents a new approach to three-dimensional analysis of MNP distributions - scanning magnetic force nanotomography as applied to the study of tumor tissues. Correlative reconstruction of MNP distributions and nanostructure features of the studied tissues made it possible to quantitatively estimate the parameters of three-dimensional distributions of composite nanoparticles based on silicon and iron oxide obtained by femtosecond laser ablation and injected intravenously and intratumorally into tumor tissue samples of B16/F1 mouse melanoma. The developed technology based on the principles of scanning probe nanotomography is applicable for studying the features of three-dimensional micro- and nanoscale distributions of magnetic nanoparticles in biomaterials, cells and tissues of various types.

Nanohybrid Structures Based on Plasmonic or Fluorescent Nanoparticles and Retinal-Containing Proteins.

Rhodopsins are light-sensitive membrane proteins enabling transmembrane charge separation (proton pump) on absorption of a light quantum. Bacteriorhodopsin (BR) is a transmembrane protein from halophilic bacteria that belongs to the rhodopsin family. Potential applications of BR are considered so promising that the number of studies devoted to the use of BR itself, its mutant variants, as well as hybrid materials containing BR in various areas grows steadily. Formation of hybrid structures combining BR with nanoparticles is an essential step in promotion of BR-based devices. However, rapid progress, continuous emergence of new data, as well as challenges of analyzing the entire data require regular reviews of the achievements in this area. This review is devoted to the issues of formation of materials based on hybrids of BR with fluorescent semiconductor nanocrystals (quantum dots) and with noble metal (silver, gold) plasmonic nanoparticles. Recent data on formation of thin (mono-) and thick (multi-) layers from materials containing BR and BR/nanoparticle hybrids are presented.

Supramolecular nanostructures based on bacterial reaction center proteins and quantum dots.

Design of the nanostructures based on membrane proteins (the key functional elements of biomembranes) and colloid nanoparticles is a fascinating field at the interface of biochemistry and colloids, nanotechnology and biomedicine. The review discusses the main achievements in the field of ultrathin films prepared from bacterial reaction center proteins and light-harvesting complexes, as well as these complexes tagged with quantum dots. The principles of preparation of these thin films and their structure and properties at different interfaces are described; as well as their characteristics estimated using a combination of the modern interfacial techniques (absorption and fluorescence spectroscopy, atomic force and Brewster angle microscopy, etc.) are discussed. Further approaches to develop the nanostructures based on the membrane proteins and quantum dots are suggested. These supramolecular nanostructures are promising prototypes of the materials for photovoltaic, optoelectronic and biosensing applications.