V.R. Cherkasov

Smart multifunctional nanoagents for in situ monitoring of small molecules with a switchable affinity towards biomedical targets

The great diversity of nanomaterials provides ample opportunities for constructing effective agents for biomedical applications ranging from biosensing to drug delivery. Multifunctional nanoagents that combine several features in a single particle are of special interest due to capabilities that substantially exceed those of molecular drugs. An ideal theranostic agent should simultaneously be an advanced biosensor to identify a disease and report the diagnosis and a biomedical actuator to treat the disease. While many approaches were developed to load a nanoparticle with various drugs for actuation of the diseased cells (e.g., to kill them), the nanoparticle-based approaches for the localized biosensing with real-time reporting of the marker concentration severely lag behind. Here, we show a smart in situ nanoparticle-based biosensor/actuator system that dynamically and reversibly changes its structural and optical properties in response to a small molecule marker to allow real-time monitoring of the marker concentration and adjustment of the system ability to bind its biomedical target. Using the synergistic combination of signal readout based on the localized surface plasmon resonance and an original method of fabrication of smart ON/OFF-switchable nanoagents, we demonstrate reversible responsiveness of the system to a model small molecule marker (antibiotic chloramphenicol) in a wide concentration range. The proposed approach can be used for the development of advanced multifunctional nanoagents for theranostic applications.

Optical method for studying self-assembly of various nanoparticles in liquids

We demonstrate that the localized surface plasmon resonance applied for studying the colloid noble metal particle interactions can be also used for investigation of metal/non-metal nanoparticle interactions. Using the spectral shift of resonance as a criterion of colloid complex formation, the method can be adapted for exploration of bio-modulated self-assembly processes to be used in life science, for development of smart materials, etc.

Stimuli-responsive nano- and microstructures based on gold nanoparticles

Gold nanoparticles (GNPs) is a well established tool for a wide range of applications in different research fields. Here, we demonstrate the possibility for their effective use in stimuli-responsive enzyme-based logic-gated systems. Such smart materials can be the promising as a base for novel nanorobotic devices that employ changes of physical properties of the environment (light, temperature, etc.) as logical inputs.

Synthesis of magnetic silica nanomarkers with controlled physicochemical properties

Magnetic markers which can be detected with an extremely high sensitivity with the method of magnetic particle quantification (MPQ) were synthesized. Using a controlled Stober reaction, a set of magnetic silica markers of different sizes and zeta potentials was obtained. The use of a carboxymethyl dextran polymer to stabilize the magnetite particles during the synthesis made it possible to substantially reduce the detection limit of the obtained construct, which opens up new opportunities for creating effective diagnostic nanoagents.