A combined experimental and DFT study of metal core/indocyanine green shell hybrid nanoparticles.

Indocyanine green (ICG) is the FDA-approved fluorescent dye used for in vivo medical imaging, diagnostics, and photothermal therapy. However, this dye is easily degradable in the human vascular system, and therefore its stabilization is preferable. In this work, ICG molecules were stabilized by their adsorption on the surface of the L-methionine-capped Ag and Au nanoparticles (Ag and Au @LM NPs) in aqueous colloidal dispersions. The result is the formation of hybrid metal core/ICG shell NPs in colloidal dispersions. Additionally, colloidal dispersions were stabilized, indicating a double effect of ICG adsorption. The obtained hybrid NPs were studied experimentally (UV-Vis spectrophotometry, HRTEM, DLS, FTIR) and theoretically (DFT calculations). HRTEM revealed that the interplanar spacing between adjacent planes of NPs decreases after the dye adsorption. The results obtained from the DFT study confirmed the formation of a covalent bond between the oxygen from ICG dye SO3- group and metal NPs. Considering the characteristics of both components of the NPs/ICG hybrid system, the authors assume that this hybrid system can exhibit the synergistic effect that could lead to more successful theranostic treatment of cancer in nanomedicine.

Nano/Microcarriers in Drug Delivery: Moving the Timeline to Contemporary.

Treatment of various diseases, especially cancer treatment, includes the potential use of different types of nanoparticles and nanostructures as drug carriers. However, searching for less toxic and more efficient therapy requires further progress, wherein recent developments in medicine increasingly include the use of various advanced nanostructures. Their more successful application might be achieved by leveling imbalances between the potentiality of different nanostructures and the demands required for their safe use. Biocompatibility, biodegradability, prolonged circulation time and enhanced accumulation and uptake by cells are some of the key preconditions for their usage in efficient drug delivery. Thanks to their greatly tunable functions, they are major building blocks for manufacturing novel materials. Nevertheless, given that their toxicity is questionable, their practical application is challenging. Hereof, before entering the sphere of human consumption, it is of critical importance to perform more studies regarding their toxicity and drug distribution. This review emphasizes recent advances in nanomedicine, employing different kinds of conventionally used nanoparticles as well as novel nanoparticles and nanostructures. Special emphasis is placed on micro/nanomotors (MNMs), discussing their opportunities, limitations, challenges and possible applications in drug delivery and outlining some perspectives in the nanomedicine area.

Na, K-ATPase as a Biological Target for Gold(III) Complexes: A Theoretical and Experimental Approach.

BACKGROUND: Gold-based complexes represent a new class of potential metallodrugs. Although their action mechanism is not entirely understood, it was shown that gold complexes inhibit some enzymes' activities. Among them, Na,K-ATPase is emerging as an essential target for various anticancer drugs. The functionalization of nanoparticles by gold(III) complexes could facilitate their delivery into the cells and enable the following of their distribution in the target tissues. OBJECTIVE: The paper presents an overview of Na,K-ATPase interaction with representative and structurally related cytotoxic gold(III) complexes. The results obtained by the employment of theoretical methods (DFT and docking studies) combined with the experimental approach involving a variety of nanotechnology-base techniques (UV/Vis, Raman and fluorescence spectroscopy, CD, AFM, DLS) are discussed. Detailed information was obtained on the enzyme's conformational and structural changes upon binding the gold(III) complexes. The experimentally determined reaction parameters (constants of dissociation and the reaction stoichiometry) were predicted theoretically. CONCLUSION: The presented results offer further support to the view that Na,K-ATPase may be a relevant biomolecular target for cytotoxic gold(III) compounds of medicinal interest.